KENYA RAILWAYS
TENDER FOR
PROPOSED REHABILITATION OF NAIROBI COMMUTER RAIL ADMINISTRATIVE OFFICES AT KENYA RAILWAYS,
HEADQUARTERS
TENDER No. KR/SCM/107/2019-2020
CLOSING DATE: WEDNESDAY 17, 2020 CLOSING TIME: 10:00 AM
The Managing Director Kenya Railways P.O. Box 30121-00100 NAIROBI, KENYA
A
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TABLE OF CONTENTS
SECTION I: INVITATION FOR TENDERS .................................... 6
SECTION II: INSTRUCTIONS TO TENDERER ............................ 7
SECTION III: TENDER DATA SHEET ....................................... 24
SECTION IV: GENERAL CONDITIONS OF CONTRACT ........... 33
SECTION V: CONTRACT DATA SHEET .................................... 59
SECTION VI: SPECIFICATIONS ............................................... 69
SECTION VIII: BILL OF QUANTITIES ..................................... 264
SECTION IX: TENDER FORMS .............................................. 231
SECTION X: FORMS OF SECURITY ...................................... 242
SECTION XI: APPLICATION TO PUBLIC PROCUREMENT ADMINISTRATIVE REVIEW BOARD .................................. 259
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ABBREVIATIONS AND ACRONYMS
CDS Contract Data Sheet
GCC General Conditions of Contract
IFT Invitation for Tender
ITT Instruction to Tenderers
PE Procuring Entity
PM Project Manager
PPDA 2015Public Procurement and `Assets Disposal Act, 2015
PPRA Public Procurement Regulatory Authority
STD Standard Tender Documents
SOR Statement of Requirements
SP Service Provider
TDS Tender Data Sheet
VAT Value Added Tax
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INTRODUCTION Kenya Railways (KR) is a State Corporation established in 1978 under the Kenya Railways Act (Cap 397) of the Laws of Kenya. The overall mandate of the Corporation then was to provide a coordinated and integrated system of rail and inland waterways transport services and inland port facilities within Kenya. The Act was amended through The Kenya Railways (Amendment) Act 2005 to make it possible for the Board of Directors to enter into concession agreements or other forms of management for the provision of rail transport services. Following this Amendment, KR conceded railway operations to Rift Valley Railways Ltd (K) from November 1, 2006 for 25 years for freight services and 1 year for passenger services. At the time, Kenya Railways was mandated to promote, facilitate and participate in the National and Metropolitan Railway development through:
Developing a Standard Gauge Railway network within the country and connected to neighbouring countries
Developing rail commuter services within and around major towns in Kenya (Nairobi, Mombasa, Nakuru, Eldoret and Kisumu)
The Corporation has since undergone numerous developments, with the 2006 Concession agreement signed with the Rift Valley Railways (Kenya) being terminated in July, 2017. Subsequently, the Corporation has taken back the role of management of the concession and operations of the Commuter Rail, in addition to that of management of non-conceded assets. Another development is the Corporation's recent completion of the implementation of the first phase of the country's mega-flagship project, the Standard Gauge Railway (SGR), with operations of the Madaraka Express on course. Further to this, the Corporation recently revised its Strategic Plan, now guided by the SP of 2017-2022, with our new Vision “To be a provider of world class rail services” and our new Mission “To develop an integrated rail network and provide efficient and safe rail services”. With this, KR serves as a blueprint that will catapult the sector towards world-class railway infrastructure, operations and services, making KR a pace setter and reference point on railway matters in the region. In pursuit of our new strategic vision, the purpose of KR is:
• To develop new railways projects and rehabilitate existing infrastructure and facilities through proper planning and effective project implementation.
• To ensure that efficiency is a hallmark of our operations. We ensure that available resources are deployed in providing freight and passenger services to our customers. Railway undertakings are carried out in a safe and sustainable manner for the sake of our environmental conservation, financial wellbeing of the Corporation and our customers for the overall economic prosperity of our country in the long term.
The above can only be realized by applying the core values of business currently employed at the state Corporation. These are:
Integrity: We are guided by probity and highest business ethics in carrying out our business.
Accountability: we are committed to being accountable and responsible to our customers and stakeholders.
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Reliability: We strive to be reliable, dependable and consistent in delivering world class rail services. We will deliver services within the specified time and standard to the satisfaction of our customers.
Safety: We promise to pay special attention to detail in the safety and security requirements of our customers, workers and the community. We guarantee that fidelity to safety and security will underpin all our activities and operations.
Collaboration: We will work jointly with stakeholders to ensure efficient service delivery and provide effective solutions to customers. We are committed to team work in pursuit of our common vision for the railways industry.
In this regard, KR now invites tenders from competent firms registered by National Construction Authority for Proposed Rehabilitation of Nairobi Commuter Rail Administrative Offices at Kenya Railways, Headquarters
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SECTION I: INVITATION FOR TENDERERS Tender Reference No. KR/SCM/107/2019-2020
Tender Name: Proposed Rehabilitation of Nairobi Commuter Rail Administrative
Offices at Kenya Railways, Headquarters
1.1 The Kenya Railways Corporation invites sealed tenders for the Proposed
Rehabilitation of Nairobi Commuter Rail Administrative Offices at Kenya Railways, Headquarters
1.2 Interested eligible candidates may obtain further information from and inspect the
tender documents at Kenya Railways HQs, P.O. Box 30121-00100, Nairobi Haile Selassie Avenue, Block A Ground Floor, Supply Chain Management Department during normal working hours
1.3 A complete set of tender documents may be obtained by interested candidates
upon payment of a non-refundable fee of Kshs1,000/-
1.4 Bidders who download the document from KR Website, PPIP and IFMIS MUST register their interest immediately by sending an email to [email protected] stating their names, email, postal and telephone address.
1.5 Prices quoted should be net inclusive of all taxes, must be in Kenya shillings and shall remain valid for 150 days from the closing date of tender.
1.6 Completed tender documents are to be enclosed in plain sealed envelopes marked with Tender name and reference number and be deposited in the Tender Box at the Reception, Kenya Railways Headquarters, Block C Ground Floor the so as to be received on or before Wednesday June 17, 2020 at 10:00 AM.
1.7 Tenders will be opened immediately thereafter in the presence of the candidates or
their representatives who choose to attend at the Conference Room on the Conference Room at Block C on 1sT Floor, Kenya Railways Headquarters, Workshop Road, Nairobi.
1.8 Tenderer SHALL Submit a Tender Security of Kshs. 700,000.00 in form of a Bank Guarantee from a Commercial Bank registered in Kenya Valid for at Least 150 days from the date of tender opening.
1.9 Tenderer must serialize all the documents provided with the tender document as per section 74 (i) of the PPAD Act, 2015 (1,2,3,4,5……….to the last page).
GENERAL MANAGER - SCM FOR: MANAGING DIRECTOR
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SECTION II: INSTRUCTIONS TO TENDERERS (ITT)
Table of Clauses ABBREVIATIONS AND ACRONYMS ......................................... 3
SECTION II: INSTRUCTIONS TO TENDERERS (ITT) ............... 6
A. Introduction ...............................................9
1. Scope of Tender...................................................................9
2. Source of Funds ...................................................................9
3. Eligible Tenderers ..............................................................10
4. One Tender per Tenderer ................................................. 11
5. Alternative Tenders by Tenderers ..................................... 12
6. Cost of Tendering.............................................................. 12
7. Site Visit and Pre-Tender Meeting .................................... 13
B. Tendering Documents ........................... 14
8. Content of Tendering Documents ..................................... 14
9. Clarification of Tendering Documents ............................... 15
10. Amendments of the Tendering Documents ...................... 15
C. Preparation of Tenders .......................... 16
11. Language of Tender .......................................................... 16
12. Documents Constituting the Tender ..................................16
13. Documents Establishing Eligibility and Qualifications of the
Tenderer .................................................................................... 17
14. Lots Package .....................................................................19
15. Form of Tender ..................................................................19
16. Tender Prices .....................................................................19
17. Tender Currencies ............................................................ 20
18. Tender Validity Period ....................................................... 20
19. Tender Security and Tender Securing Declaration ........... 21
20. Format and Signing of Tender .......................................... 23
D. Submission of Tenders ......................... 24
21. Sealing and Marking of Tenders ....................................... 24
22. Deadline for Submission of Tenders ................................. 25
23. Late Tenders ..................................................................... 25
24. Modification, Substitution and Withdrawal of Tenders ...... 25
E. Opening and Evaluation of Tenders .... 26
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38. Procuring Entities Right to Vary Quantities at the Time of Award 35
39. Notification of Award ..........................................................35
40. Signing of Contract.............................................................37
41. Performance Security.........................................................37
42. Advance Payment ..............................................................38
43. Adjudicator .........................................................................38
G. Review of Procurement Decisions ....... 38
44. Right to Review ..................................................................39
45. Time Limit on Review .........................................................39
46. Submission of Applications for Review by the Public
25. Opening of Tenders .......................................................... 26
26. Confidentiality.................................................................... 28
27. Clarification of Tenders ..................................................... 29
28. Preliminary Examination of Tenders ................................. 29
29. Correction of Errors ........................................................... 30
30. Conversion to Single Currency ......................................... 31
31. Comparison of Tenders. ................................................... 31
32. National Preference .......................................................... 32
33. Determination of the Lowest Evaluated Tender ................ 33
34. Post-qualification of Tenderer ........................................... 33
F. Award of Contract ...................................34
35. Criteria of Award ............................................................... 34
36. Clarifications ...................................................................... 34
37. Procuring Entity’s Right to accept any Tender and to Reject any
or all Tenders ............................................................................. 35
Procurement Administrative Review Board ............................... 39
47. Decision by the Public Procurement Administrative Review
Board .........................................................................................40
48. Appeal on the decision of the Review Board .....................41
22. Health and Safety...............................................................59
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INSTRUCTIONSTOTENDERERS.
1. General/Eligibility/Qualifications/Joint venture/Cost of tendering
1.1 The Employer as defined in the Appendix to Conditions of Contract invites tenders for Works Contract as described in the tender documents. The successful tenderer will be expected to complete the Works by the Intended Completion Date specified in the tender documents.
1.2 All tenderers shall provide the Qualification Information, a statement that the tenderer (including all members of a joint venture and subcontractors) is not associated, or has not been associated in the past, directly or indirectly, with the Consultant or any other entity that has prepared the design, specifications, and other documents for the project or being proposed as Project Manager for the Contract. A firm that has been engaged by the Employer to provide consulting services for the preparation or supervision of the Works, and any of its affiliates, shall not be eligible to tender.
1.3 All tenderers shall provide in the Form of Tender and Qualification Information, a preliminary description of the proposed work method and schedule, including drawings and charts, as necessary.
1.4 In the event that pre-qualification of potential tenderers has been undertaken, only tenders from pre-qualified tenderers will be considered for award of Contract. These qualified tenderers should submit with their tenders any information updating their original pre-qualification applications or, alternatively, confirm in their tenders that the originally submitted pre-qualification information remains essentially correct as of the date of tender submission.
1.5 Where no pre-qualification of potential tenderers has been done, all tenderers shall include the following information and documents with their tenders , unless otherwise stated:
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(a) copies of original documents defining the constitution or legal status, place of registration, and principal place of business; written power of attorney of the signatory of the tender to commit the tenderer:
(b) total monetary value of construction work performed for each of the last five years:
(c) experience in works of a similar nature and size for each of the last five years, and details of work under way or contractually committed; and names and addresses of clients who may be contacted for further information on these contracts;
(d) Major items of construction equipment proposed to carry out the Contract and an undertaking that they will be available for the Contract.
(e) Qualifications and experience of key site management and technical personnel proposed for the Contract and an undertaking that they shall be available for the Contract.
(f) reports on the financial standing of the tenderer, such as profit and loss statements and auditor’s reports for the past five years;
(g) evidence of adequacy of working capital for this Contract (access to line(s) of credit and availability of other financial resources);
(h) authority to seek references from the tenderer’s bankers;
(i) information regarding any litigation, current or during the last five years, in which the tenderer is involved, the parties concerned and disputed amount; and
(j) proposals for subcontracting components of the Works amounting to more than 10 percent of the Contract Price.
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1.6 Tenders submitted by a joint venture of two or more firms as partners shall comply with the following requirements, unless otherwise stated:
(a) the tender shall include all the information listed in clause 1.5 above for each joint venture partner;
(b) the tender shall be signed so as to be legally binding on all partners;
(c) all partners shall be jointly and severally liable for the execution of the Contract in accordance with the Contract terms;
(d) one of the partners will be nominated as being in charge, authorized to incur liabilities, and receive instructions for and on behalf of all partners of the joint venture; and
(e) the execution of the entire Contract, including payment, shall be done exclusively with the partner in charge.
1.7 To qualify for award of the Contract, tenderers shall meet the following minimum qualifying criteria;
(a)annual volume of construction work of at least 2.5 times the estimated annual cash flow for the Contract;
(b)experience as main contractor in the construction of at least
(c) two works of a nature and complexity equivalent to the Works over the last 10 years (to comply with this requirement, works cited should be at least 70 percent complete);
(d)proposals for the timely acquisition (own, lease, hire, etc.) of the essential equipment listed as required for the Works;
(e)a Contract manager with at least five years’ experience in works of an equivalent nature and volume, including no less than three years as Manager; and
(f) liquid assets and/or credit facilities, net of other contractual commitments and exclusive of any advance payments which
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may be made under the Contract, of no less than 4 months of the estimated payment flow under this Contract.
1.8 The figures for each of the partners of a joint venture shall be added together to determine the tenderer’s compliance with the minimum qualifying criteria of clause 1.7 (a) and (e); however, for a joint venture to qualify, each of its partners must meet at least 25 percent of minimum criteria 1.7 (a), (b) and (e) for an individual tenderer, and the partner in charge at least 40 percent of those minimum criteria. Failure to comply with this requirement will result in rejection of the joint venture’s tender. Subcontractors’ experience and resources will not be taken into account in determining the tenderer’s compliance with the qualifying criteria, unless otherwise stated.
1.9 Each tenderer shall submit only one tender, either individually or as a partner in a joint venture. A tenderer who submits or participates in more than one tender (other than as a subcontractor or in cases of alternatives that have been permitted or requested) will cause all the proposals with the tenderer’s participation to be disqualified.
1.10 The tenderer shall bear all costs associated with the preparation and submission of his tender, and the Employer will in no case be responsible or liable for those costs.
1.11 The tenderer, at the tenderer’s own responsibility and risk, is encouraged to visit and examine the Site of the Works and its surroundings, and obtain all information that may be necessary for preparing the tender and entering into a contract for construction of the Works. The costs of visiting the Site shall be at the tenderer’s own expense.
1.12 The procuring entity’s employees, committee members, board members and their relative (spouse and children) are not eligible to participate in the tender.
1.13 The price to be changed for the tender document shall not exceed Kshs.1,000/=
1.14 The procuring entity shall allow the tenderer to review the tender document free of charge before purchase.
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2. Tender Documents
2.1 The complete set of tender documents comprises the documents listed below and any addenda issued in accordance with Clause 2.4.
(a) These Instructions to Tenderers (b) Form of Tender and Qualification Information (c) Conditions of Contract (d) Appendix to Conditions of Contract (e) Specifications (f) Drawings (g) Bills of Quantities (h) Forms of Securities
2.2 The tenderer shall examine all Instructions, Forms to be filled and Specifications in the tender documents. Failure to furnish all information required by the tender documents, or submission of a tender not substantially responsive to the tendering documents in every respect will be at the tenderer’s risk and may result in rejection of his tender.
2.3 A prospective tenderer making an inquiry relating to the tender documents may notify the Employer in writing or by cable, telex or facsimile at the address indicated in the letter of invitation to tender. The Employer will only respond to requests for clarification received earlier than seven days prior to the deadline for submission of tenders. Copies of the Employer’s response will be forwarded to all persons issued with tendering documents, including a description of the inquiry, but without identifying its source.
2.4 Before the deadline for submission of tenders, the Employer may modify the tendering documents by issuing addenda. Any addendum thus issued shall be part of the tendering documents and shall be communicated in writing or by cable, telex or facsimile to all tenderers. Prospective tenderers shall acknowledge receipt of each addendum in writing to the Employer.
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2.5 To give prospective tenderers reasonable time in which to take an addendum into account in preparing their tenders, the Employer shall extend, as necessary, the deadline for submission of tenders, in accordance with Clause 4.2 here below.
3. Preparation of Tenders
3.1 All documents relating to the tender and any correspondence shall be in English language.
3.2 The tender submitted by the tenderer shall comprise the following:
(a) These Instructions to Tenderers, Form of Tender, Conditions of Contract, Appendix to Conditions of Contract and Specifications;
(b) Tender Security;
(c) Priced Bill of Quantities;
(d) Qualification Information Form and Documents;
(e) Alternative offers where invited; and
(f) Any other materials required to be completed and submitted by the tenderers.
3.3 The tenderer shall fill in rates and prices for all items of the Works described in the Bill of Quantities. Items for which no rate or price is entered by the tenderer will not be paid for when executed and shall be deemed covered by the other rates and prices in the Bill of Quantities. All duties, taxes, and other levies payable by the Contractor under the Contract, or for any other cause relevant to the Contract, as of 30 days prior to the deadline for submission of tenders, shall be included in the tender price submitted by the tenderer.
3.4 The rates and prices quoted by the tenderer shall only be subject to adjustment during the performance of the Contract if provided
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for in the Appendix to Conditions of Contract and provisions made in the Conditions of Contract.
3.5 The unit rates and prices shall be in Kenya Shillings.
3.6 Tenders shall remain valid for a period of sixty (60) days from the date of submission. However, in exceptional circumstances, the Employer may request that the tenderers extend the period of validity for a specified additional period. The request and the tenderers’ responses shall be made in writing. A tenderer may refuse the request without forfeiting the Tender Security. A tenderer agreeing to the request will not be required or permitted to otherwise modify the tender, but will be required to extend the validity of Tender Security for the period of the extension, and in compliance with Clause 3.7 - 3.11 in all respects.
3.7 The tenderer shall furnish, as part of the tender, a Tender Security in the amount and form specified in the appendix to invitation to tenderers. This shall be in the amount not exceeding 2 percent of the tender price
3.8 The format of the Tender Security should be in accordance with the form of Tender Security included in Section G - Standard forms or any other form acceptable to the Employer . Tender Security shall be valid for 30 days beyond the validity of the tender.
3.9 Any tender not accompanied by an acceptable Tender Security shall be rejected. The Tender Security of a joint venture must define as “Tenderer” all joint venture partners and list them in the following manner: a joint venture consisting of” …………”,”…………”,and “…………”.
3.10 The Tender Securities of unsuccessful tenderers will be returned within 28 days of the end of the tender validity period specified in Clause 3.6.
3.11 The Tender Security of the successful tenderer will be discharged when the tenderer has signed the Contract Agreement and furnished the required Performance Security.
3.12 The Tender Security may be forfeited
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(a) if the tenderer withdraws the tender after tender opening during the period of tender validity;
(b) if the tenderer does not accept the correction of the tender price, pursuant to Clause 5.7;
(c) in the case of a successful tenderer, if the tenderer fails within the specified time limit to
(i) sign the Agreement, or
(ii) furnish the required Performance Security.
3.13 Tenderers shall submit offers that comply with the requirements of the tendering documents, including the basic technical design as indicated in the Drawings and Specifications. Alternatives will not be considered, unless specifically allowed in the invitation to tender. If so allowed, tenderers wishing to offer technical alternatives to the requirements of the tendering documents must also submit a tender that complies with the requirements of the tendering documents, including the basic technical design as indicated in the Drawings and Specifications. In addition to submitting the basic tender, the tenderer shall provide all information necessary for a complete evaluation of the alternative, including design calculations, technical specifications, breakdown of prices, proposed construction methods and other relevant details. Only the technical alternatives, if any, of the lowest evaluated tender conforming to the basic technical requirements shall be considered.
3.14 The tenderer shall prepare one original of the documents comprising the tender documents as described in Clause 3.2 of these Instructions to Tenderers, bound with the volume containing the Form of Tender, and clearly marked “ORIGINAL”. In addition, the tenderer shall submit copies of the tender, in the number specified in the invitation to tender, and clearly marked as “COPIES”. In the event of discrepancy between them, the original shall prevail.
3.15 The original and all copies of the tender shall be typed or written in indelible ink and shall be signed by a person or persons duly
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authorised to sign on behalf of the tenderer, pursuant to Clause 1.5 (a) or 1.6 (b), as the case may be. All pages of the tender where alterations or additions have been made shall be initialled by the person or persons signing the tender.
3.16 Clarification of tenders shall be requested by the tenderer to be received by the procuring entity not later than 7 days prior to the deadline for submission of tenders.
3.17 The procuring entity shall reply to any clarifications sought by the tenderer within 3 days of receiving the request to enable the tenderer to make timely submission of its tender.
3.18 The tender security shall be in the amount of 0.5 – 2 per cent of the tender price.
4. Submission of Tenders
4.1 The tenderer shall seal the original and all copies of the tender in two inner envelopes and one outer envelope, duly marking the inner envelopes as “ORIGINAL” and “COPIES” as appropriate.
The inner and outer envelopes shall: (a) be addressed to the Employer at the address provided in the
invitation to tender;
(b) bear the name and identification number of the Contract as defined in the invitation to tender; and
(c) provide a warning not to open before the specified time and date for tender opening.
4.2 Tenders shall be delivered to the Employer at the address specified above not later than the time and date specified in the invitation to tender. However, the Employer may extend the deadline for submission of tenders by issuing an amendment in accordance with Sub-Clause 2.5 in which case all rights and obligations of the Employer and the tenderers previously subject to the original deadline will then be subject to the new deadline.
4.3 Any tender received after the deadline prescribed in clause 4.2
will be returned to the tenderer un-opened.
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4.4 Tenderers may modify or withdraw their tenders by giving notice in writing before the deadline prescribed in clause 4.2. Each tenderer’s modification or withdrawal notice shall be prepared, sealed, marked, and delivered in accordance with clause 3.13 and 4.1, with the outer and inner envelopes additionally marked “MODIFICATION” and “WITHDRAWAL”, as appropriate. No tender may be modified
after the deadline for submission of tenders.
4.5 Withdrawal of a tender between the deadline for submission of tenders and the expiration of the period of tender validity specified in the invitation to tender or as extended pursuant to Clause 3.6 may result in the forfeiture of the Tender Security pursuant to Clause 3.11.
4.6 Tenderers may only offer discounts to, or otherwise modify the prices of their tenders by submitting tender modifications in accordance with Clause 4.4 or be included in the original tender submission.
5. Tender Opening and Evaluation
5.1 The tenders will be opened by the Employer, including modifications made pursuant to Clause 4.4, in the presence of the tenderers’ representatives who choose to attend at the time and in the place specified in the invitation to tender. Envelopes marked “WITHDRAWAL” shall be opened and read out first. Tenderers’ and Employer’s representatives who are present during the opening shall sign a register evidencing their attendance.
5.2 The tenderers’ names, the tender prices, the total amount of each tender and of any alternative tender (if alternatives have been requested or permitted), any discounts, tender modifications and withdrawals, the presence or absence of Tender Security, and such other details as may be considered appropriate, will be announced by the Employer at the opening. Minutes of the tender opening, including the information disclosed to those present will be prepared by the Employer.
5.3 Information relating to the examination, clarification, evaluation, and comparison of tenders and recommendations for the award of
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Contract shall not be disclosed to tenderers or any other persons not officially concerned with such process until the award to the successful tenderer has been announced. Any effort by a tenderer to influence the Employer’s officials, processing of tenders or award decisions may result in the rejection of his tender.
5.4 To assist in the examination, evaluation, and comparison of tenders, the Employer at his discretion, may ask any tenderer for clarification of the tender, including breakdowns of unit rates. The request for clarification and the response shall be in writing or by cable, telex or facsimile but no change in the price or substance of the tender shall be sought, offered, or permitted except as required to confirm the correction of arithmetic errors discovered in the evaluation of the tenders in accordance with Clause 5.7.
5.5 Prior to the detailed evaluation of tenders, the Employer will determine whether each tender (a) meets the eligibility criteria defined in Clause 1.7;(b) has been properly signed; (c) is accompanied by the required securities; and (d) is substantially responsive to the requirements of the tendering documents. A substantially responsive tender is one which conforms to all the terms, conditions and specifications of the tendering documents, without material deviation or reservation. A material deviation or reservation is one (a) which affects in any substantial way the scope, quality, or performance of the works; (b) which limits in any substantial way, inconsistent with the tendering documents, the Employer’s rights or the tenderer’s obligations under the Contract; or (c) whose rectification would affect unfairly the competitive position of other tenderers presenting substantially responsive tenders.
5.6 If a tender is not substantially responsive, it will be rejected, and may not subsequently be made responsive by correction or withdrawal of the nonconforming deviation or reservation.
5.7 Tenders determined to be substantially responsive will be checked for any arithmetic errors. Errors will be corrected as follows:
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(a) where there is a discrepancy between the amount in figures and the amount in words, the amount in words will prevail; and
(b) where there is a discrepancy between the unit rate and the line item total resulting from multiplying the unit rate by the quantity, the unit rate as quoted will prevail, unless in the opinion of the Employer, there is an obvious typographical error, in which case the adjustment will be made to the entry containing that error.
(c) In the event of a discrepancy between the tender amount as stated in the Form of Tender and the corrected tender figure in the main summary of the Bill of Quantities, the amount as stated in the Form of Tender shall prevail.
(d) The Error Correction Factor shall be computed by expressing the difference between the tender amount and the corrected tender sum as a percentage of the corrected Builder’s Work (i.e. Corrected tender sum less P.C. and Provisional Sums)
(e) The Error Correction Factor shall be applied to all Builder’s Work (as a rebate or addition as the case may be) for the purposes of valuations for Interim Certificates and valuation of variations.
(f) the amount stated in the tender will be adjusted in accordance with the above procedure for the correction of errors and, with concurrence of the tenderer, shall be considered as binding upon the tenderer. If the tenderer does not accept the corrected amount, the tender may be rejected and the Tender Security may be forfeited in accordance with clause 3.11.
5.8 The Employer will evaluate and compare only the tenders determined to be substantially responsive in accordance with Clause 5.5.
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5.9 In evaluating the tenders, the Employer will determine for each tender the evaluated tender price by adjusting the tender price as follows:
(a) making any correction for errors pursuant to clause 5.7;
(b) excluding provisional sums and the provision, if any, for contingencies in the Bill of Quantities, but including Dayworks where priced competitively.
(c) making an appropriate adjustment for any other acceptable variations, deviations, or alternative offers submitted in accordance with clause 3.12; and
(d) making appropriate adjustments to reflect discounts or other price modifications offered in accordance with clause 4.6
5.10 The Employer reserves the right to accept or reject any variation, deviation, or alternative offer. Variations, deviations, and alternative offers and other factors which are in excess of the requirements of the tender documents or otherwise result in unsolicited benefits for the Employer will not be taken into account in tender evaluation.
5.11 The tenderer shall not influence the Employer on any matter relating to his tender from the time of the tender opening to the time the Contract is awarded. Any effort by the Tenderer to influence the Employer or his employees in his decision on tender evaluation, tender comparison or Contract award may result in the rejection of the tender.
5.12 Firms incorporated in Kenya where indigenous Kenyans own 51% or more of the share capital shall be allowed a 10% preferential bias provided that they do not sub-contract work valued at more than 50% of the Contract Price excluding Provisional Sums to an non-indigenous sub-contractor.
6. Award of Contract
6.1 Subject to Clause 6.2, the award of the Contract will be made to
the tenderer whose tender has been determined to be substantially
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responsive to the tendering documents and who has offered the lowest evaluated tender price, provided that such tenderer has been determined to be (a) eligible in accordance with the provision of Clauses 1.2, and (b) qualified in accordance with the provisions of clause 1.7 and 1.8.
6.2 Notwithstanding clause 6.1 above, the Employer reserves the right
to accept or reject any tender, and to cancel the tendering process and reject all tenders, at any time prior to the award of Contract, without thereby incurring any liability to the affected tenderer or tenderers or any obligation to inform the affected tenderer or tenderers of the grounds for the action.
6.3 The tenderer whose tender has been accepted will be notified of the award prior to expiration of the tender validity period in writing or by cable, telex or facsimile. This notification (hereinafter and in all Contract documents called the “Letter of Acceptance”) will state the sum (hereinafter and in all Contract documents called the “Contract Price”)that the Employer will pay the Contractor in consideration of the execution, completion, and maintenance of the Works by the Contractor as prescribed by the Contract. At the same time the other tenderers shall be informed that their tenders have not been successful.
The contract shall be formed on the parties signing the contract.
6.4 The Agreement will incorporate all agreements between the Employer and the successful tenderer. Within 14 days of receipt the successful tenderer will sign the Agreement and return it to the Employer.
6.5 Within 21 days after receipt of the Letter of Acceptance, the successful tenderer shall deliver to the Employer a Performance Security in the amount stipulated in the Appendix to Conditions of Contract and in the form stipulated in the Tender documents. The Performance Security shall be in the amount and specified form
6.6 Failure of the successful tenderer to comply with the requirements of clause 6.5 shall constitute sufficient grounds for cancellation of the award and forfeiture of the Tender Security.
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6.7 Upon the furnishing by the successful tenderer of the Performance Security, the Employer will promptly notify the other tenderers that their tenders have been unsuccessful.
6.8 Preference where allowed in the evaluation of tenders shall not be allowed for contracts not exceeding one year (12 months)
6.9 The tender evaluation committee shall evaluate the tender within 30 days of the validity period from the date of opening the tender.
6.10 The parties to the contract shall have it signed within 30 days from the date of notification of contract award unless there is an administrative review request.
6.11 Contract price variations shall not be allowed for contracts not exceeding one year (12 months)
6.12 Where contract price variation is allowed, the valuation shall not exceed 15% of the original contract price.
6.13 Price variation request shall be processed by the procuring entity within 30 days of receiving the request.
6.14 The procuring entity may at any time terminate procurement proceedings before contract award and shall not be liable to any person for the termination.
6.15 The procuring entity shall give prompt notice of the termination to the tenderers and on request give its reasons for termination within 14 days of receiving the request from any tenderer.
6.16 A tenderer who gives false information in the tender document about its qualification or who refuses to enter into a contract after notification of contract award shall be considered for debarment from participating in future public procurement.
7. Corrupt and Fraudulent practices
7.1 The procuring entity requires that tenderers observe the highest standards of ethics during procurement process and execution of contracts. A tenderer shall sign a declaration that he has not and will not be involved in corrupt and fraudulent practices.
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SECTION III: TENDER DATA SHEET
Tender Data Sheet (TDS)
Instructions to Tenderers Clause Reference
TDS Reference
Number
ITT Clause
Number
Amendments of, and Supplements to, Clauses in the Instruction to Tenderers
A. Introduction
1. 1.1 The Procuring Entity is Kenya Railways Corporation P.O. Box 30121-00100 NAIROBI
2. 1.1 Name of Project is Proposed Rehabilitation of Nairobi Commuter Rail Administrative Offices at Kenya Railways HHEAD 3. 1.2 The expected completion date of the works is 8 Weeks after site handover.
4. 1.3 The Objective of the Project is to: - Rehabilitation of Administrative Offices
1.5(d) Delete the word ‘Major’ and substitute with the
word ‘Relevant’ Key equipment required to carry
out the works include:-
1.7 Add the following after the words ‘qualifying
criteria;’(attach the relevant supporting
documents as evidence)
5. 2.1 Name o f t h e Procuring is Kenya Railways
Financial Year 2019/2020
Works under the contracts: -
Demolition and Repairs
Mechanical Repairs
Plumbing Works
Redesign of Areas and Partitioning Works
Other associated Works as provided for in the Bill of Quantity
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6. 3.1 Only Tenderers registered as Building Works Contractor Category NCA 4 and above with the National Construction Authority.
7. 5.1 Alternative Tenders are Not al lowed in
this Tender.
8. 5.2 Alternative time for completion Not applicable
10. 7.3 Pre-Tender meeting will not take place
B. Tendering Documents
12. 8.2 The number of copies to be completed and returned with the Tender is 1(One) Original and 3 (Three) Copies.
13. 9.1 Address for clarification of Tendering Document is Kenya Railways Headquarters, Workshops Road off Haile Selassie Avenue,
P.O. Box 30121-00100 NAIROBI
14. 9.2 Period to Respond to request for clarification by
the Procuring Entity is 7 (Seven) working days
Period Prior to deadline for submission of
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Tenders for Tenderers to request clarification is
7 (seven) days
C. Preparation of Tenders
15. 11.1 Language of Tender and all correspondence shall be English
16. 13.3 Other information or materials required to be completed and submitted by Tenderers :
Copies of original documents defining the constitution or legal status, place of
registration, and principal, place of business; written power of attorney authorizing the signatory of the Tender to commit the
Tenderer.
Certified copy of Certificate of Incorporation, VAT registration, PIN registration and Valid Tax compliance certificate.
The minimum required annual volume of construction work for the successful Tenderer in any of the last 3 years shall be: Kshs 50,000,000/=
Experience as prime contractor in the construction of at least one project of a nature and complexity equivalent to the Works the last 2 years or the period stated in a) above (to comply with this requirement, works cited should be at least 70 percent complete).
The essential equipment to be made available for the Contract by the successful Tenderer (proposals for timely acquisition or own, lease, hire, etc.) shall be:
Scaffolding
Terrazo Grinding Machine
Concrete Mixer
Concrete Vibrator
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A Site Agent with a minimum of 8 year experience in works of an equivalent nature and volume.
Evidence of adequate working capital for this contract: The applicant shall demonstrate that they have access to, or has available, liquid assets, unencumbered real assets, lines of credit and other financial means sufficient to meet the construction cash flow for a period of Twelve (12) Weeks, estimated at Kshs.15 million, net of the applicant’s commitments for other contracts.
The audited Accounts for the last three (3) years shall be submitted and must demonstrate the soundness of the applicant’s financial position, showing long-term profitability. Where necessary the procuring entity will make inquiries with the applicant’s bankers.
Information regarding litigation history: the applicant should provide accurate information on any litigation or arbitration resulting from contracts completed or under its execution over the last five years. A consistent history of awards against the applicant or any partner of a joint venture may result in failure of the application.
17. 13.4 In the case of Joint Venture each partner shall submit information required under Clause ITT Clause 13.4.
18. 16.4 The price shall be fixed
19. 17.1 The currency in which the prices shall be quoted shall be: Kenyan Shilling.
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20. 17.2 The authority for establishing the rates of 30.2 exchange shall be Central Bank of Kenya.
The applicable date for exchange rates for tendering and evaluation purposes is 28 days earlier than the final deadline for the submission of tenders.
21. 18.1 The Tender validity period shall be 150 days.
22. 19.1 The bidder must submit a duly filled and signed Tender security declaration form.
23. 20.1 In addition to the 1 original of the Tender, the Tenderer should submit 3 copies of the Tender.
24. 20.2 Written confirmation of authorization is the power of the attorney.
D. Submission of Tenders
25. 21.2 a) Tenders shall be submitted to Kenya Railways Corporation Workshops Road, Off Haile Selassie Avenue Procurement Department, First Floor NAIROBI
26. 21.2 b) Project name: Proposed Rehabilitation of Nairobi Commuter Rail Administrative Offices
Tender number:KR/SCM/107/2019-2020 Time and date for submission: On or before, WEDNESDAY JUNE 17, 2020 at 10:00 AM
27. 22.1 The deadline for Tender submission is
Day: WEDNESDAY JUNE 17, 2020
Date: Time :10:00 AM
28. 22.3 The extension of the deadline for submission of Tenders shall be made not later than seven days before the expiry of the original deadline.
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29 24.4 Expiry of Tender validity is 150 days from date of opening of the tenders
E. Opening and Evaluation of Tenders
29. 25.1 The Tender opening shall take place at: Workshops Road, Off Haile Selassie Avenue Kenya Railways Headquarters First Floor, Sattima Conference Room Nairobi Kenya
Date: WEDNESDAY JUNE 17, 2020 Time: 10:00 AM
30. 32.3 Additional Preference is not applicable
31. 34.1 Post- qualification will be undertaken
32. 38.1 Percentage for goods and services increase or decrease is 10%
Percentage for works increase or decrease is 15%
Percentage for cumulative value of all contract variations shall not exceed 25% of total contract
price.
F. Award of Contract
33. 41.1 The amount of Performance Security shall be 10% of the Contract Price
34. 42.1 There shall be no advance Payment
35. 43.1 The proposed adjudicator for the project will be as appointed by the chairman of the Chartered Institute of Arbitrators (Kenya Branch).
G. Review of Procurement Decisions
37. 46.1 The address for submitting appeals to Administrative Review Board : The Secretary,
Public Procurement Administrative Review Board , The Public Procurement Regulatory Authority, 10th Floor ,National Bank House, P.O. B ox 58583-00200, NAIROBI, Kenya.
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SECTION III CONDITIONS OF CONTRACT
Table of Contents
1Definitions …………………………………………………15
2Interpretation………………………………………………17
3Language and Law…………………………………………17
4Project Manager’s Decisions………………………………17
5Delegation…………………………………………………18
6Communications …………………………………………18
7Sub Contracting …………………………………………18
8Other Contractors ………………………………………18
9Personnel …………………………………………………18
10Works………………………………………………………19
11Safety and temporary works ………………………………19
12Discoveries …………………………………………………19
13 Work Programme …………………………………………19 -20
14Possession of site …………………………………………20
15Access to site ……………………………………………20
16Instructions ………………………………………………20
17Extension or Acceleration of completion date …………20
18Management Meetings …………………………………21
19Early Warning ……………………………………………21
20Defects …………………………………………………… 21 – 22
21Bills of Quantities …………………………………………22
22Variations …………………………………………………22- 23
23Payment certificates, currency of payments and
Advance Payments ………………………………………23
24Compensation events ……………………………………25 – 27
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25Price Adjustment …………………………………………27 – 29
26Retention …………………………………………………29
27Liquidated Damages………………………………………29
28Securities …………………………………………………29
29Day Works ……………………………………………… 29 – 30
30Liability and Insurance ……………………………………30 – 31
31Completion and taking over ………………………………31
32Final Account ……………………………………………31
33Termination ………………………………………………31 – 32
34Payment upon termination …………………………………32 – 33
35Release from performance …………………………………33
36Corrupt gifts and payments of commission ………………33 – 34
37Settlement of Disputes ………………………………………34 – 36
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CONDITIONSOFCONTRACT
1. Definitions
1.1 In this Contract, except where context otherwise requires, the following terms shall be interpreted as indicated;
“Bill of Quantities” means the priced and completed Bill of
Quantities forming part of the tender.
“Compensation Events” are those defined in Clause 24 hereunder.
“The Completion Date” means the date of completion of the
Works as certified by the Project Manager, in accordance with Clause 31.
“The Contract” means the agreement entered into between the
Employer and the Contractor as recorded in the Agreement Form and signed by the parties including all attachments and appendices thereto and all documents incorporated by reference therein to execute, complete, and maintain the Works,
“The Contractor” refers to the person or corporate body whose tender to carry out the Works has been accepted by the Employer.
“The Contractor’s Tender”is the completed tendering document
submitted by the Contractor to the Employer.
“The Contract Price” is the price stated in the Letter of Acceptance and thereafter as adjusted in accordance with the provisions of the Contract.
“Days” are calendar days; “Months” are calendar months.
“A Defect” is any part of the Works not completed in accordance with the Contract.
“The Defects Liability Certificate” is the certificate issued by
Project Manager upon correction of defects by the Contractor.
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“The Defects Liability Period” is the period named in the Contract Data and calculated from the Completion Date.
“Drawings” include calculations and other information provided or approved by the Project Manager for the execution of the Contract.
“Dayworks” are Work inputs subject to payment on a time basis for labour and the associated materials and plant.
“Employer”, or the “Procuring entity” as defined in the Public
Procurement Regulations (i.e. Central or Local Government administration, Universities, Public Institutions and Corporations, etc) is the party who employs the Contractor to carry out the Works.
“Equipment” is the Contractor’s machinery and vehicles brought
temporarily to the Site for the execution of the Works.
“The Intended Completion Date” is the date on which it is
intended that the Contractor shall complete the Works. The Intended Completion Date may be revised only by the Project Manager by issuing an extension of time or an acceleration order.
“Materials” are all supplies, including consumables, used by the Contractor for incorporation in the Works.
“Plant” is any integral part of the Works that shall have a
mechanical, electrical, chemical, or biological function.
“Project Manager” is the person named in the Appendix to Conditions of Contract (or any other competent person appointed by the Employer and notified to the Contractor, to act in replacement of the Project Manager) who is responsible for supervising the execution of the Works and administering the Contract and shall be an “Architect” or a “Quantity Surveyor” registered under the Architects and Quantity Surveyors Act Cap 525 or an “Engineer” registered under Engineers Registration Act Cap 530.
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“Site” is the area defined as such in the Appendix to Condition of
Contract.
“Site Investigation Reports” are those reports that may be
included in the tendering documents which are factual and interpretative about the surface and subsurface conditions at the Site.
“Specifications” means the Specifications of the Works included
in the Contract and any modification or addition made or approved by the Project Manager.
“Start Date” is the latest date when the Contractor shall
commence execution of the Works. It does not necessarily coincide with the Site possession date(s).
“A Subcontractor” is a person or corporate body who has a
Contract with the Contractor to carry out a part of the Work in the Contract, which includes Work on the Site.
“Temporary works” are works designed, constructed, installed,
and removed by the Contractor which are needed for construction or installation of the Works.
“A Variation” is an instruction given by the Project Manager which
varies the Works.
“The Works” are what the Contract requires the Contractor to construct, install, and turnover to the Employer, as defined in the Appendix to Conditions of Contract.
2. Interpretation
2.1 In interpreting these Conditions of Contract, singular also means plural, male also means female or neuter, and the other way around. Headings have no significance. Words have their normal meaning in English Language unless specifically defined. The Project Manager will provide instructions clarifying queries about these Conditions of Contract.
2.2 If sectional completion is specified in the Appendix to Conditions of Contract, reference in the Conditions of Contract to the Works,
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the Completion Date and the Intended Completion Date apply to any section of the Works (other than references to the Intended Completion Date for the whole of the Works).
2.3 The following documents shall constitute the Contract documents and shall be interpreted in the following order of priority;
(1) Agreement,
(2) Letter of Acceptance,
(3) Contractor’s Tender,
(4) Appendix to Conditions of Contract,
(5) Conditions of Contract,
(6) Specifications,
(7) Drawings,
(8) Bill of Quantities,
(9) Any other documents listed in the Appendix to Conditions of
Contract as forming part of the Contract.
Manager
copies
necessary
copy
either
with
Immediately after the execution of the Contract, the Project shall
furnish both the Employer and the Contractor with two each of
all the Contract documents. Further, as and when the Project
Manager shall furnish the Contractor [always with a
to the Employer] with three [3] copies of such further drawings or details or descriptive schedules as are reasonably necessary
to explain or amplify the Contract drawings or to enable the Contractor to carry out and complete the Works in accordance
these Conditions.
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3. Language and Law
3.1 Language of the Contract and the law governing the Contract shall be English language and the Laws of Kenya respectively unless otherwise stated.
4 Project Manager’s Decisions
4.1 Except where otherwise specifically stated, the Project Manager will decide contractual matters between the Employer and the Contractor in the role representing the Employer.
5 Delegation
5.1 The Project Manager may delegate any of his duties and responsibilities to others after notifying the Contractor.
6 Communications
6.1 Communication between parties shall be effective only when in writing. A notice shall be effective only when it is delivered.
7 Subcontracting
7.1 The Contractor may subcontract with the approval of the Project Manager, but may not assign the Contract without the approval of the Employer in writing. Subcontracting shall not alter the Contractor’s obligations.
8 Other Contractors
8.1 The Contractor shall cooperate and share the Site with other contractors, public authorities, utilities etc. as listed in the Appendix to Conditions of Contract and also with the Employer, as per the directions of the Project Manager. The Contractor shall also provide facilities and services for them. The Employer may modify the said List of Other Contractors etc., and shall notify the Contractor of any such modification.
9 Personnel
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9.1 The Contractor shall employ the key personnel named in the Qualification Information, to carry out the functions stated in the said Information or other personnel approved by the Project Manager. The Project Manager will approve any proposed replacement of key personnel only if their relevant qualifications and abilities are substantially equal to or better than those of the personnel listed in the Qualification Information. If the Project Manager asks the Contractor to remove a person who is a member of the Contractor’s staff or work force, stating the reasons, the Contractor shall ensure that the person leaves the Site within seven days and has no further connection with the Work in the Contract.
10 Works
10.1 The Contractor shall construct and install the Works in accordance with the Specifications and Drawings. The Works may commence on the Start Date and shall be carried out in accordance with the Program submitted by the Contractor, as updated with the approval of the Project Manager, and complete them by the Intended Completion Date.
11 Safety and Temporary Works
11.1 The Contractor shall be responsible for the design of temporary works. However before erecting the same, he shall submit his designs including specifications and drawings to the Project Manager and to any other relevant third parties for their approval. No erection of temporary works shall be done until such approvals are obtained.
11.2 The Project Manager’s approval shall not alter the Contractor’s responsibility for design of the Temporary works and all drawings prepared by the Contractor for the execution of the temporary or permanent Works, shall be subject to prior approval by the Project Manager before they can be used.
11.3 The Contractor shall be responsible for the safety of all activities on the Site.
12.Discoveries
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12.1 Anything of historical or other interest or of significant value unexpectedly discovered on Site shall be the property of the Employer. The Contractor shall notify the Project Manager of such discoveries and carry out the Project Manager’s instructions for dealing with them.
13. Work Program
13.1 Within the time stated in the Appendix to Conditions of Contract, the Contractor shall submit to the Project Manager for approval a program showing the general methods, arrangements, order, and timing for all the activities in the Works. An update of the program shall be a program showing the actual progress achieved on each activity and the effect of the progress achieved on the timing of the remaining Work, including any changes to the sequence of the activities.
The Contractor shall submit to the Project Manager for approval an updated program at intervals no longer than the period stated in the Appendix to Conditions of Contract. If the Contractor does not submit an updated program within this period, the Project Manager may withhold the amount stated in the said Appendix from the next payment certificate and continue to withhold this amount until the next payment after the date on which the overdue program has been submitted. The Project Manager’s approval of the program shall not alter the Contractor’s obligations. The Contractor may revise the program and submit it to the Project Manager again at any time. A revised program shall show the effect of Variations and Compensation Events.
14. Possession of Site
14.1 The Employer shall give possession of all parts of the Site to the Contractor. If possession of a part is not given by the date stated in the Appendix to Conditions of Contract, the Employer will be deemed to have delayed the start of the relevant activities, and this will be a Compensation Event.
15. Access to Site
15.1 The Contractor shall allow the Project Manager and any other person is favored by the Project Manager, access to the Site and
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to any place where work in connection with the Contract is being carried out or is intended to be carried out.
16.Instructions
16.1 The Contractor shall carry out all instructions of the Project Manager which are in accordance with the Contract.
17. Extension or Acceleration of Completion Date
17.1 The Project Manager shall extend the Intended Completion Date if a Compensation Event occurs or a variation is issued which makes it impossible for completion to be achieved by the Intended Completion Date without the Contractor taking steps to accelerate the remaining Work, which would cause the Contractor to incur additional cost. The Project Manager shall decide whether and by how much to extend the Intended Completion Date within 21 days of the Contractor asking the Project Manager in writing for a decision upon the effect of a Compensation Event or variation and submitting full supporting information. If the Contractor has failed to give early warning of a delay or has failed to cooperate in dealing with a delay, the delay caused by such failure shall not be considered in assessing the new (extended) Completion Date.
63.1 No bonus for early completion of the Works shall be paid to the Contractor by the Employer.
18. Management Meetings
18.1 A Contract management meeting shall be held monthly and attended by the Project Manager and the Contractor. Its business shall be to review the plans for the remaining Work and to deal with matters raised in accordance with the early warning procedure. The Project Manager shall record the minutes of management meetings and provide copies of the same to those attending the meeting and the Employer. The responsibility of the parties for actions to be taken shall be decided by the Project Manager either at the management meeting or after the management meeting and stated in writing to all who attended the meeting.
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19. Early Warning
19.1 The Contractor shall warn the Project Manager at the earliest opportunity of specific likely future events or circumstances that may adversely affect the quality of the Work, increase the Contract Price or delay the execution of the Works. The Project Manager may require the Contractor to provide an estimate of the expected effect of the future event or circumstance on the Contract Price and Completion Date. The estimate shall be provided by the Contractor as soon as reasonably possible.
19.2 The Contractor shall cooperate with the Project Manager in making and considering proposals on how the effect of such an event or circumstance can be avoided or reduced by anyone involved in the Work and in carrying out any resulting instructions of the Project Manager.
20.Defects
20.1 The Project Manager shall inspect the Contractor’s work and notify the Contractor of any defects that are found. Such inspection shall not affect the Contractor’s responsibilities. The Project Manager may instruct the Contractor to search for a defect and to uncover and test any Work that the Project Manager considers may have a defect. Should the defect be found, the cost of uncovering and making good shall be borne by the Contractor, However, if there is no defect found, the cost of uncovering and making good shall be treated as a variation and added to the Contract Price.
20.2 The Project Manager shall give notice to the Contractor of any defects before the end of the Defects Liability Period, which begins at Completion, and is defined in the Appendix to Conditions of Contract. The Defects Liability Period shall be extended for as long as defects remain to be corrected.
20.3 Every time notice of a defect is given, the Contractor shall correct the notified defect within the length of time specified by the Project Manager’s notice. If the Contractor has not corrected a defect within the time specified in the Project Manager’s notice, the Project Manager will assess the cost of having the defect
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corrected by other parties and such cost shall be treated as a variation and be deducted from the Contract Price.
21. Bills Of Quantities
21.1 The Bills of Quantities shall contain items for the construction, installation, testing and commissioning of the Work to be done by the Contractor. The Contractor will be paid for the quantity of the Work done at the rate in the Bills of Quantities for each item.
21.2 If the final quantity of the Work done differs from the quantity in the Bills of Quantities for the particular item by more than 25 percent and provided the change exceeds 1 percent of the Initial Contract price, the Project Manager shall adjust the rate to allow for the change.
21.3 If requested by the Project Manager, the Contractor shall provide the Project Manager with a detailed cost breakdown of any rate in the Bills of Quantities.
22.Variations
22.1 All variations shall be included in updated programs produced by the Contractor.
22.2 The Contractor shall provide the Project Manager with a quotation for carrying out the variations when requested to do so. The Project Manager shall assess the quotation, which shall be given within seven days of the request or within any longer period as may be stated by the Project Manager and before the Variation is ordered.
22.3 If the work in the variation corresponds with an item description in the Bills of Quantities and if in the opinion of the Project Manager, the quantity of work is not above the limit stated in Clause 21.2 or the timing of its execution does not cause the cost per unit of quantity to change, the rate in the Bills of Quantities shall be used to calculate the value of the variation. If the cost per unit of quantity changes, or
43
if the nature or timing of the work in the variation does not correspond with items in the Bills of Quantities, the quotation by the Contractor shall be in the form of new rates for the relevant items of Work.
22.4 If the Contractor’s quotation is unreasonable, the Project Manager may order the variation and make a change to the Contract price, which shall be based on the Project Manager’s own forecast of the effects of the variation on the Contractor’s costs.
22.5 If the Project Manager decides that the urgency of varying the Work would prevent a quotation being given and considered without delaying the Work, no quotation shall be given and the variation shall be treated as a Compensation Event.
22.6 The Contractor shall not be entitled to additional payment for costs that could have been avoided by giving early warning.
22.7 When the Program is updated, the Contractor shall provide the Project Manager with an updated cash flow forecast.
23. Payment Certificates, Currency of Payments and Advance Payments
23.1 The Contractor shall submit to the Project Manager monthly applications for payment giving sufficient details of the Work done and materials on Site and the amounts which the Contractor considers himself to be entitled to. The Project Manager shall check the monthly application and certify the amount to be paid to the Contractor within 14 days. The value of Work executed and payable shall be determined by the Project Manager.
23.2 The value of Work executed shall comprise the value of the quantities of the items in the Bills of Quantities completed, materials delivered on Site, variations and compensation events. Such materials shall become the property of the Employer once the Employer has paid the Contractor for their value . Thereafter, they shall not be removed from Site without the Project Manager’s instructions except for use upon the Works.
23.3 Payments shall be adjusted for deductions for retention. The
Employer shall pay the Contractor the amounts certified by the Project Manager within 30 days of the date of issue of each
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certificate. If the Employer makes a late payment, the Contractor shall be paid simple interest on the late payment in the next payment. Interest shall be calculated on the basis of number of days delayed at a rate three percentage points above the Central Bank of Kenya’s average rate for base lending prevailing as of the first day the payment becomes overdue.
23.4 If an amount certified is increased in a later certificate or as a result of an award by an Arbitrator, the Contractor shall be paid interest upon the delayed payment as set out in this clause. Interestshall be calculated from the date upon which the increased amount would have been certified in the absence of dispute.
23.5 Items of the Works for which no rate or price has been entered in will not be paid for by the Employer and shall be deemed covered by other rates and prices in the Contract.
23.6 The Contract Price shall be stated in Kenya Shillings. All payments to the Contractor shall be made in Kenya Shillings and foreign currency in the proportion indicated in the tender, or agreed prior to the execution of the Contract Agreement and indicated therein. The rate of exchange for the calculation of the amount of foreign currency payment shall be the rate of exchange indicated in the Appendix to Conditions of Contract. If the Contractor indicated foreign currencies for payment other than the currencies of the countries of origin of related goods and services the Employer reserves the right to pay the equivalent at the time of payment in the currencies of the countries of such goods and services. The Employer and the Project Manager shall be notified promptly by the Contractor of an changes in the expected foreign currency requirements of the Contractor during the execution of the Works as indicated in the Schedule of Foreign Currency Requirements and the foreign and local currency portions of the balance of the Contract Price shall then be amended by agreement between Employer and the Contractor in order to reflect appropriately such changes.
23.7 In the event that an advance payment is granted, the following shall apply:-
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a) On signature of the Contract, the Contractor shall at his request, and without furnishing proof of expenditure, be entitled to an advance of 10% (ten percent) of the original amount of the Contract. The advance shall not be subject to retention money.
b) No advance payment may be made before the Contractor has submitted proof of the establishment of deposit or a directly liable guarantee satisfactory to the Employer in the amount of the advance payment. The guarantee shall be in the same currency as the advance.
c) Reimbursement of the lump sum advance shall be made by deductions from the Interim payments and where applicable from the balance owing to the Contractor. Reimbursement shall begin when the amount of the sums due under the Contract reaches 20% of the original amount of the Contract. It shall have been completed by the time 80% of this amount is reached.
The amount to be repaid by way of successive deductions shall be calculated by means of the formula:
R=A(x1 – x11)
80 – 20 Where:
R=the amount to be reimbursed
A=the amount of the advance which has been granted
X1 = the amount of proposed cumulative payments as a percentage of the original amount of the Contract. This figure will exceed 20% but not exceed 80%.
X11 = the amount of the previous cumulative payments as
a percentage of the original amount of the Contract. This figure will be below 80%but not less than 20%.
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d) with each reimbursement the counterpart of the directly liable guarantee may be reduced accordingly.
24. Compensation Events
24.1 The following issues shall constitute Compensation Events:
(a) The Employer does not give access to a part of the Site by the Site Possession Date stated in the Appendix to Conditions of Contract.
(b) The Employer modifies the List of Other Contractors, etc., in a way that affects the Work of the Contractor under the Contract.
(c) The Project Manager orders a delay or does not issue drawings, specifications or instructions required for execution of the Works on time.
(d) The Project Manager instructs the Contractor to uncover or to carry out additional tests upon the Work, which is then found to have no defects.
(e) The Project Manager unreasonably does not approve a
subcontract to be let.
(f) Ground conditions are substantially more adverse than could reasonably have been assumed before issuance of the Letter of Acceptance from the information issued to tenderers (including the Site investigation reports), from information available publicly and from a visual inspection of the Site.
(g) The Project Manager gives an instruction for dealing with an unforeseen condition, caused by the Employer or additional work required for safety or other reasons.
(h) Other c o n t r a c t o r s , p u b l i c a u t h o r i t i e s , u t i l i t i e s , or the Employer does not work within the dates and o t h e r constraints stated in the Contract, and they cause delay or extra cost to the Contractor.
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(i) The effects on the Contractor of any of the Employer’s risks.
(j) The Project Manager unreasonably delays issuing a Certificate of Completion.
(k) Other compensation events described in the Contract or determined by the Project Manager shall apply.
24.2 If a compensation event would cause additional cost or would prevent the Work being completed before the Intended Completion Date, the Contract Price shall be increased and/or the Intended Completion Date shall be extended. The Project Manager shall decide whether and by how much the Contract Price shall be increased and whether and by how much the Intended Completion Date shall be extended.
24.3 As soon as information demonstrating the effect of each compensation event upon the Contractor’s forecast cost has been provided by the Contractor, it shall be assessed by the Project Manager, and the Contract Price shall be adjusted accordingly. If the Contractor’s forecast is deemed unreasonable, the Project Manager shall adjust the Contract Price based on the Project Manager’s own forecast. The Project Manager will assume that the Contractor will react competently and promptly to the event.
24.4 The Contractor shall not be entitled to compensation to the extent
that the Employer’s interests are adversely affected by the Contractor not having given early warning or not having co- operated with the Project Manager.
24.5 Prices shall be adjusted for fluctuations in the cost of inputs only if provided for in the Appendix to Conditions of Contract.
24.6 The Contractor shall give written notice to the Project Manager of his intention to make a claim within thirty days after the event giving rise to the claim has first arisen. The claim shall be submitted within thirty days thereafter.
Provided always that should the event giving rise to the claim of continuing effect, the Contractor shall submit an interim claim
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within the said thirty days and a final claim within thirty days of the end of the event giving rise to the claim.
25. Price Adjustment
25.1 The Project Manager shall adjust the Contract Price if taxes, duties and other levies are changed between the date 30 days before the submission of tenders for the Contract and the date of Completion. The adjustment shall be the change in the amount of tax payable by the Contractor.
25.2 The Contract Price shall be deemed to be based on exchange rates current at the date of tender submission in calculating the cost to the Contractor of materials to be specifically imported (by express provisions in the Contract Bills of Quantities or Specifications) for permanent incorporation in the Works. Unless otherwise stated in the Contract, if at any time during the period of the Contract exchange rates shall be varied and this shall affect the cost to the Contractor of such materials, then the Project Manager shall assess the net difference in the cost of such materials. Any amount from time to time so assessed shall be added to or deducted from the Contract Price, as the case may be.
25.3 Unless otherwise stated in the Contract, the Contract Price shall be deemed to have been calculated in the manner set out below and in sub-clauses 25.4 and 25.5 and shall be subject to adjustment in the events specified thereunder;
(i) The prices contained in the Contract Bills of Quantities shall be deemed to be based upon the rates of wages and other emoluments and expenses as determined by the Joint Building Council of Kenya (J.B.C.) and set out in the schedule of basic rates issued 30 days before the date for submission of tenders.A copy of the schedule used by the Contractor in his pricing shall be attached in the Appendix to Conditions of Contract.
(ii) Upon J.B.C. determining that any of the said rates of wages or other emoluments and expenses are increased or decreased, then the Contract Price shall be increased or decreased by the amount assessed by the Project Manager
49
based upon the difference, expressed as a percentage, between the rate set out in the schedule of basic rates issued 30 days before the date for submission of tenders and the rate published by the J.B.C. and applied to the quantum of labour incorporated within the amount of Work remaining to be executed at the date of publication of such increase or decrease.
(iii) No adjustment shall be made in respect of changes in the rates of wages and other emoluments and expenses which occur after the date of Completion except during such other period as may be granted as an extension of time under clause 17.0 of these Conditions.
25.4 The prices contained in the Contract Bills of Quantities shall be deemed to be based upon the basic prices of materials to be permanently incorporated in the Works as determined by the J.B.C. and set out in the schedule of basic rates issued 30 days before the date for submission of tenders. A copy of the schedule used by the Contractor in his pricing shall be attached in the Appendix to Conditions of Contract.
25.5 Upon the J.B.C. determining that any of the said basic prices are increased or decreased then the Contract Price shall be increased or decreased by the amount to be assessed by the Project Manager based upon the difference between the price set out in the schedule of basic rates issued 30 days before the date for submission of tenders and the rate published by the J.B.C. and applied to the quantum of the relevant materials which have not been taken into account in arriving at the amount of any interim certificate under clause 23 of these Conditions issued before the date of publication of such increase or decrease.
25.6 No adjustment shall be made in respect of changes in basic prices of materials which occur after the date for Completion except during such other period as may be granted as an extension of time under clause 17.0 of these Conditions.
25.7 The provisions of sub-clause 25.1 to 25.2 herein shall not apply in respect of any materials included in the schedule of basic rates.
26.Retention
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26.1 The Employer shall retain from each payment due to the Contractor the proportion stated in the Appendix to Conditions of Contract until Completion of the whole of the Works. On Completion of the whole of the Works, half the total amount retained shall be repaid to the Contractor and the remaining half when the Defects Liability Period has passed and the Project Manager has certified that all defects notified to the Contractor before the end of this period have been corrected.
27. Liquidated Damages
27.1 The Contractor shall pay liquidated damages to the Employer at the rate stated in the Appendix to Conditions of Contract for each day that the actual Completion Date is later than the Intended Completion Date. The Employer may deduct liquidated damages from payments due to the Contractor. Payment of liquidated damages shall not alter the Contractor’s liabilities.
27.2 If the Intended Completion Date is extended after liquidated damages have been paid, the Project Manager shall correct any overpayment of liquidated damages by the Contractor by adjusting the next payment certificate. The Contractor shall be paid interest on the overpayment, calculated from the date of payment to the date of repayment, at the rate specified in Clause 23.30
28.Securities
28.1 The Performance Security shall be provided to the Employer no later than the date specified in the Letter of Acceptance and shall be issued in an amount and form and by a reputable bank acceptable to the Employer, and denominated in Kenya Shillings. The Performance Security shall be valid until a date 30 days beyond the date of issue of the Certificate of Completion.
29.Dayworks
29.1 If applicable, the Dayworks rates in the Contractor’s tender shall be used for small additional amounts of Work only when the Project Manager has given written instructions in advance for additional work to be paid for in that way.
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29.2 All work to be paid for as Dayworks shall be recorded by the Contractor on Forms approved by the Project Manager. Each completed form shall be verified and signed by the Project Manager within two days of the Work being done.
29.3 The Contractor shall be paid for Dayworks subject to obtaining signed Dayworks forms.
30. Liability and Insurance
30.1 From the Start Date until the Defects Correction Certificate has been issued, the following are the Employer’s risks:
(a) The risk of personal injury, death or loss of or damage to property (excluding the Works, Plant, Materials and Equipment), which are due to;
(i) use or occupation of the Site by the Works or for the purpose of the Works, which is the unavoidable result of the Works, or
(ii) negligence, breach of statutory duty or interference with any legal right by the Employer or by any person employed by or contracted to him except the Contractor.
(b) The risk of damage to the Works, Plant, Materials, and Equipment to the extent that it is due to a fault of the Employer or in Employer’s design, or due to war or radioactive contamination directly affecting the place where the Works are being executed.
30.2 From the Completion Date until the Defects Correction Certificate has been issued, the risk of loss of or damage to the Works, Plant, and Materials is the Employer’s risk except loss or damage due to;
(a) a defect which existed on or before the Completion Date.
(b) an event occurring before the Completion Date, which was not itself the Employer’s risk
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(c) the activities of the Contractor on the Site after the Completion Date.
30.3 From the Start Date until the Defects Correction Certificate has been issued, the risks of personal injury, death and loss of or damage to property (including, without limitation, the Works, Plant, Materials, and Equipment) which are not Employer’s risk are Contractor’s risks.
The Contractor shall provide, in the joint names of the Employer and the Contractor, insurance cover from the Start Date to the end of the Defects Liability Period, in the amounts stated in the Appendix to Conditions of Contract for the following events; (a) loss of or damage to the Works, Plant, and Materials; (b) loss of or damage to Equipment; (c) loss of or damage to property (except the Works, Plant,
Materials, and Equipment) in connection with the Contract, and
(d) personal injury or death.
30.4 Policies and certificates for insurance shall be delivered by the Contractor to the Project Manager for the Project Manager’s approval before the Start Date. All such insurance shall provide for compensation required to rectify the loss or damage incurred.
30.5 If the Contractor does not provide any of the policies and certificates required, the Employer may effect the insurance which the Contractor should have provided and recover the premiums from payments otherwise due to the Contractor or, if no payment is due, the payment of the premiums shall be a debt due.
30.6 Alterations to the terms of an insurance shall not be made without the approval of the Project Manager. Both parties shall comply with any conditions of insurance policies.
31. Completion and taking over
31.1 Upon deciding that the Works are complete, the Contractor shall issue a written request to the Project Manager to issue a Certificate of Completion of the Works. The Employer shall take
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over the Site and the Works within seven [7] days of the Project Manager’s issuing a Certificate of Completion.
32. Final Account
32.1 The Contractor shall issue the Project Manager with a detailed account of the total amount that the Contractor considers payable to him by the Employer under the Contract before the end of the Defects Liability Period. The Project Manager shall issue a Defects Liability Certificate and certify any final payment that is due to the Contractor within 30 days of receiving the Contractor’s account if it is correct and complete. If it is not, the Project Manager shall issue within 30 days a schedule that states the scope of the corrections or additions that are necessary. If the final account is still unsatisfactory after it has been resubmitted, the Project Manager shall decide on the amount payable to the Contractor and issue a Payment Certificate. The Employer shall pay the Contractor the amount due in the Final Certificate within 60 days.
33.Termination
33.1 The Employer or the Contractor may terminate the Contract if the other party causes a fundamental breach of the Contract. These
fundamental breaches of Contract shall include, but shall not be limited to, the following;
(a) the Contractor stops work for 30 days when no stoppage of work is shown on the current program and the stoppage has not been 53isfavor53d by the Project Manager;
(b) the Project Manager instructs the Contractor to delay the progress of the Works, and the instruction is not withdrawn within 30 days;
(c) the Contractor is declared bankrupt or goes into liquidation other than for a reconstruction or amalgamation;
(d) a payment certified by the Project Manager is not paid by the Employer to the Contractor within 30 days (for Interim Certificate) or 60 days (for Final Certificate)of issue.
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(e) the Project Manager gives notice that failure to correct a particular defect is a fundamental breach of Contract and the Contractor fails to correct it within a reasonable period of time determined by the Project Manager;
(f) the Contractor does not maintain a security, which is required.
33.2 When either party to the Contract gives notice of a breach of Contract to the Project Manager for a cause other than those listed under Clause 33.1 above, the Project Manager shall decide whether the breach is fundamental or not.
33.3 Notwithstanding the above, the Employer may terminate the Contract for convenience.
33.4 If the Contract is terminated, the Contractor shall stop work immediately, make the Site safe and secure, and leave the Site as soon as reasonably possible. The Project Manager shall immediately thereafter arrange for a meeting for the purpose of taking record of the Works executed and materials , goods, equipment and temporary buildings on Site.
34. Payment Upon Termination
34.1 If the Contract is terminated because of a fundamental breach of Contract by the Contractor, the Project Manager shall issue a certificate for the value of the Work done and materials ordered and delivered to Site up to the date of the issue of the certificate. Additional liquidated damages shall not apply. If the total amount due to the Employer exceeds any payment due to the Contractor, the difference shall be a debt payable by the Contractor.
34.2 If the Contract is terminated for the Employer’s convenience or because of a fundamental breach of Contract by the Employer, the Project Manager shall issue a certificate for the value of the Work done, materials ordered, the reasonable cost of removal of equipment, repatriation of the Contractor’s personnel employed solely on the Works, and the Contractor’s costs of protecting and securing the Works.
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34.3 The Employer may employ and pay other persons to carry out and complete the Works and to rectify any defects and may enter upon the Works and use all materials on the Site, plant, equipment and temporary works.
34.4 The Contractor shall, during the execution or after the completion of the Works under this clause remove from the Site as and when required, within such reasonable time as the Project Manager may in writing specify, any temporary buildings, plant, machinery, appliances, goods or materials belonging to or hired by him, and in default the Employer may (without being responsible for any loss or damage) remove and sell any such property of the Contractor, holding the proceeds less all costs incurred to the credit of the Contractor. Until after completion of the Works under this clause the Employer shall not be bound by any other provision of this Contract to make any payment to the Contractor, but upon such completion as aforesaid and the verification within a reasonable time of the accounts therefore the Project Manager shall certify the amount of expenses properly incurred by the Employer and, if such amount added to the money paid to the Contractor before such determination exceeds the total amount which would have been payable on due completion in accordance with this Contract the difference shall be a debt payable to the Employer by the Contractor; and if the said amount added to the said money be less than the said total amount, the difference shall be a debt payable by the Employer to the Contractor.
35. Release from Performance
35.1 If the Contract is frustrated by the outbreak of war or by any other event entirely outside the control of either the Employer or the Contractor, the Project Manager shall certify that the Contract has been frustrated. The Contractor shall make the Site safe and stop Work as quickly as possible after receiving this certificate and shall be paid for all Work carried out before receiving it.
36. Corrupt gifts and payments of commission
The Contractor shall not;
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(a) Offer or give or agree to give to any person in the service of the
Employer any gift or consideration of any kind as an inducement or reward for doing or forbearing to do or for having done or forborne to do any act in relation to the obtaining or execution of this or any other Contract for the Employer or for showing or forbearing to show favour or 56isfavor to any person in relation to this or any other contract for the Employer.
(b) Enter into this or any other contract with the Employer in connection with which commission has been paid or agreed to be paid by him or on his behalf or to his knowledge, unless before the Contract is made particulars of any such commission and of the terms and conditions of any agreement for the payment thereof have been disclosed in writing to the Employer.
Any breach of this Condition by the Contractor or by anyone employed by him or acting on his behalf (whether with or without the knowledge of the Contractor) shall be an offence under the provisions of the Public Procurement Regulations issued under The Exchequer and Audit Act Cap 412 of the Laws of Kenya.
37. Settlement Of Disputes
37.1 In case any dispute or difference shall arise between the Employer or the Project Manager on his behalf and the Contractor, either during the progress or after the completion or termination of the Works, such dispute shall be notified in writing by either party to the other with a request to submit it to arbitration and to concur in the appointment of an Arbitrator within thirty days of the notice. The dispute shall be referred to the arbitration and final decision of a person to be agreed between the parties. Failing agreement to concur in the appointment of an Arbitrator, the Arbitrator shall be appointed by the Chairman or Vice Chairman of any of the following professional institutions;
(i) Architectural Association of Kenya
(ii) Institute of Quantity Surveyors of Kenya
(iii) Association of Consulting Engineers of Kenya
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(iv) Chartered Institute of Arbitrators (Kenya Branch)
(v) Institution of Engineers of Kenya
On the request of the applying party. The institution written to first by the aggrieved party shall take precedence over all other institutions.
37.2 The arbitration may be on the construction of this Contract or on any matter or thing of whatsoever nature arising thereunder or in connection therewith, including any matter or thing left by this Contract to the discretion of the Project Manager, or the withholding by the Project Manager of any certificate to which the Contractor may claim to be entitled to or the measurement and valuation referred to in clause 23.0 of these conditions, or the rights and liabilities of the parties subsequent to the termination of Contract.
37.3 Provided that no arbitration proceedings shall be commenced on any dispute or difference where notice of a dispute or difference has not been given by the applying party within ninety days of the occurrence or discovery of the matter or issue giving rise to the dispute.
37.4 Notwithstanding the issue of a notice as stated above, the arbitration of such a dispute or difference shall not commence unless an attempt has in the first instance been made by the parties to settle such dispute or difference amicably with or without the assistance of third parties. Proof of such attempt shall be required.
37.5 Notwithstanding anything stated herein the following matters may be referred to arbitration before the practical completion of the Works or abandonment of the Works or termination of the Contract by either party:
37.5.1 The appointment of a replacement Project Manager upon the said person ceasing to act.
37.5.2 Whether or not the issue of an instruction by the Project Manager is empowered by these Conditions.
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37.5.3 Whether or not a certificate has been improperly withheld or is not in accordance with these Conditions.
37.5.4 Any dispute or difference arising in respect of war risks or war damage.
37.6 All other matters shall only be referred to arbitration after the completion or alleged completion of the Works or termination or alleged termination of the Contract, unless the Employer and the Contractor agree otherwise in writing.
37.7 The Arbitrator shall, without prejudice to the generality of his powers, have powers to direct such measurements, computations, tests or valuations as may in his opinion be desirable in order to determine the rights of the parties and assess and award any sums which ought to have been the subject of or included in any certificate.
37.8 The Arbitrator shall, without prejudice to the generality of his powers,
have powers to open up, review and revise any certificate, opinion, decision, requirement or notice and to determine all matters in dispute which shall be submitted to him in the same manner as if no such certificate, opinion, decision requirement or notice had been given.
37.9 The award of such Arbitrator shall be final and binding upon the parties.
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SECTION IV: APPENDIX TO CONDTIONS OF CONTRACT
Contract Data Sheet
Instructions for completing the Contract Data Sheet
CDS Claus e
GCC Clause
Description
1
1.1
General
The Procuring Entity is Kenya Railways Corporation P.O. Box 30121-00100 NAIROBI
The Adjudicator shall be appointed by the Chartered Institute of Arbitrators (Kenya Branch).
The Defects Notification Period is six (6) months from practical completion of works
The Contractor Manager is Project Manager, Kenya Railways
The name and identification number of the Contract is Proposed Rehabilitation of Nairobi Commuter Rail Administrative Offices at Kenya Railways, Headquarter
Tender No.KR/SCM/107/2019-2020
The Start Date shall be as agreed with the Project Manager.
The Intended Completion Date for the whole of the Works shall be 8 Weeks from date of Site hand over.
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The following documents also form part of the Contract:
(1) Agreement; (2) Letter of Acceptance; (3) Contract Data Sheet; (4) Conditions of Contract; (5) Technical Specifications; (6) Contractor’s Tender; (7) Drawings; (8) Bill of Quantities
The Site is located at Kenya Railways Headquarter
2. 2.2 Sectional completion is not applicable
3. 2.3(9) List other documents that form part of the contract if any: Standard Specifications for Building works General Specifications Part III Electrical and Mechanical Works
4. 3.1 The language of the Contract documents is English The law that applies to the Contract is the Kenyan Law.
5. 9.1 Schedule of Other Contractors, if any: Electrical and Mechanical Contractor
6. 10.1 Schedule of Key Personnel. The applicant must have suitably qualified personnel
to fill the following managerial and supervisory
positions Position Minimum
Qualification Total experi ence (years)
In similar works (years)
As Mana Supe or of simil work (year
Site Agent
Degree in Construction Management/
15 10 10
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Building Construction
Foreman - Building Works
Diploma in Civil/ Building construction Eng.
15 10 10
7. 14.1 The minimum Insurance covers shall be:
(a) Loss of or damage to the Works, Plant, and Materials: Full replacement cost but not less than the contract price
(b) Loss of or damage to Equipment: Full Replacement Cost
(c) Loss of or damage to property (except the Works, Plant, Materials, and Equipment) in connection with the Contract: Full Replacement Cost.
(d) Personal injury or death
For Contractor’s Employees- Ksh 1 million
For other People- Ksh 1 million
8. 15.1 Site Investigation Reports available to the Tenderers are: N/A
9. 22.4 The other measures include:
Minimizing the number of migrant workers employed on the project and household in the site camp
Providing access to Voluntary Counselling and Testing (VCT)
Providing psychological support and health care including prevention and treatment of opportunistic infections for workers infected and affected, as well as their families
Providing condoms (male and female) to
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workers
10. 24.1 & 47.1
The Site Possession Date shall be: Seven (7) days after Project Manager’s order to commence.
11. 28.2 Hourly Rate of Fees payable to the Adjudicator shall be as recommended by the Chartered Institute of Arbitrators (Kenya Branch)
Types of reimbursable expenses to be paid to the Adjudicator shall be as provided for in the rules of the Chartered Institute of Arbitrators (Kenya Branch).
12. 28.3 Arbitration will take place in accordance with the Laws of Kenya and the Arbitration Rules of the Chartered Institute of Arbitrators (Kenya Branch) by one or more arbitrators appointed by the Chartered Institute of Arbitrators (Kenya Branch).
13. 29.1 Appointing Authority for the Adjudicator: Chairman, Institute of Arbitration of Kenya
Time Control
14. 30.1 The Contractor shall Submit a Programme for the Works within 7 days of delivery of the Letter of
Acceptance.
15. 30.3 The period between Programme updates is 7 days.
16. 30.3 The amount to be withheld by the Project Manager in the case the contractor does not submit an updated programme is: Ksh 100,000/= until program is submitted
Quality Control
17. 38.1 The Defects Notification Period is 6 months from practical completion.
Cost Control
18. 45.7 Minimum Amount of Interim Payment Certificate will be 1 million shillings
19. 46.1 The interest rate shall be 2% above the average lending rate from Central Bank of Kenya
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20. 47.1(a) The Site Possession Date shall be: Seven (7) days after Engineers order to commence.
21. 50 The contract is not subject to price adjustment in accordance with Clause 50 of the General Conditions of Contract.
22. 51.1 The amount of retention is 10% of value of works of
Interim Payment Certificate’. Limit of retention will be 10% of contract price.
23. 52.1 The rate of liquidated damages is 0.15% of contract price per day.
52.1 62.2 (g)
The maximum amount of liquidated damages is 10% of contract price
24. 53.1 The bonus for early completion is Not applicable
25. 54.1 The amount of advance payment shall be Not applicable
26. 55.1 The Performance Security shall be 10% of the contract price
Finishing the Contract
27. 61.1 Operating manual shall be supplied by the contractor by : Not applicable
28. 61.2 The amount to be withheld by the Project Manager in the case the contractor does not submit operating manual is: Not applicable
29. 63.1 The percentage to apply to the value of the work not completed, representing the Procuring Entity’s additional cost for completing the Works, is 15%
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TENDER EVALUATION CRITERIA
This Section contains all the factors, methods and criteria that the Employer shall use to evaluate applications. The information to be provided in relation to each factor and the definitions of the corresponding terms are included in the respective Application Forms.
A. PRELIMINARY/MANDATORYREQUIREMENTS
A. PRELIMINARY REQUIREMENTS
1 The tender has been submitted in the required format as per the
advertisement and tender instructions
2
Any tender security submitted is in the required form, amount and
validity period (150 days); only from a Bank from a Commercial Bank
Registered in Kenya
3 The tender has been signed by the persons lawfully authorized to do so
(signed and stamped form of tender); Power of Attorney is Provided
4 The required number of copies of the tender has been submitted as per
the advertisement and tender instructions.
5 The tender is valid for the period required.
MANDATORY REQUIREMENTS
REQUIREMENT COMPLIED
1 Copy of Valid Certificate of Incorporation / Registration Mandatory
2 Copy of a Valid KRA Tax compliance Certificate Mandatory
3 Attach System generated Certified Copy of CR12 Certificate (For Incorporated firms only)
4 Copies of Certified Audited Accounts for any of the
Last 3 (Three) consecutive years (2016,2017,
2018,2019)
Mandatory
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5 Must provide a Contact address: Physical, Postal,
Telephone and Email address of the Firm (Confidential
Business Questionnaire Clearly indicating the list of
Directors or Partners as applicable and details of
citizenship signed and stamped
Mandatory
6 Bidder Must provide copy of registration with NCA 4 and above as a Building Works Contractor, Certificate must be
accompanied by a current NCA practicing certificate.
Mandatory
7 Bidder Must Submit a Tender Security of Kshs.
700,000.00 in form of a Bank Guarantee from a
Commercial Bank registered in Kenya Valid for at
Least 150 days from the date of tender opening
Mandatory
8 Form of tender (Properly filled, signed and stamped) Mandatory
9 Litigation History ( Provided in Form 7 Litigation History
form in the tender Document filled, signed and stamped)
Must
Declare
10 Bidder must fill the Integrity Declaration Forms (Form 8)
provided in the Tender Document.
Must
Declare
11 Bidders should have their documents paginated
(serialized) to ensure compliance with Section 74 (i)
Public Procurement and Assets Disposal Act, 2015 (in
format 1,2,3,4……..to the last page)
Mandatory
12 A Mandatory Site visit will take place at bidders
convenience. Bidders must attach filled, signed and
stamped Tender site visit form.
Mandatory
Bidders must meet all the Mandatory Requirement to proceed to
Technical Evaluation Stage. Tenderers who do not satisfy any of the above
requirements shall be considered NON-RESPONSIVE and their tenders will
not be evaluated further.
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B. TECHNICALREQUIREMENTS
1. Specific experience of the firm (Form X provided in the tender Document) Experience as prime contractor in the construction of five (5) projects of similar Works in the last 5 years. ( Similar Project refers to project of Similar Scope and Amount) As evidence Bidders must attach:-
1. Certified copies of contracts (Full Contract) for each assignment (3 marks each)
2. Proof of successful completion attach Copies of (Completion Certificate) or evidence that the work is over 70% Complete (Interim Certificate) (2 marks each)
3. Recommendation/ Reference Letters from all the Assignments listed above. (2 marks each)
35 Marks
2. EXPERIENCE OF THE FIRM -Over ten(10) years - 10 marks – 5-10 years - 5 marks – 0-5 years - 0 mark
10 Marks
3. The Bidder must Provide evidence to show his Annual volume of construction work is a minimum of Kshs 50,000,000 carried out in the last 2 consecutive years.
- Over 50million – 10 marks - Between 30 – 50 million – 5 marks - Below 30million – 0 marks
(Bidder should provide a list of works, client names and reference person as well as contacts. The evidence must be reflected on the firm’s financial statements provided)
10 Marks
4 PLANT & EQUIPMENT The Bidder must indicate the main plant and equipment considered by the company to be necessary for undertaking the project together with proof ownership or lease agreement. The essential equipment to be made available for the Contract by the Bidder
A. Scaffolding – 5 marks B. Terrazzo grinding machine – 5 marks C. Concrete Mixer – 5 marks D. Concrete Vibrators – 5 marks
(Bidder must provide current proposals/evidence for timely acquisition or own, lease, hire, etc Clearly indicating Source and Contacts for the firms if equipment are under lease)
20 Marks
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5. Qualification and Experience of Key Personnel (CV Format provided in the tender document) Bidder should provide evidence of technical Training and Experience of Bidders staff; Attach CV, Copies of Academic and professional qualification for the key staff demonstrating the following qualifications. Site Agent Qualification – 15 marks
i) CV (3 marks) ii) Degree in Civil Eng/Project Management or equivalent
construction qualification(4 marks) iii) Registration Certificate from Engineers Registration
Board. (4 marks) iv) Experience of 8 years (4 marks)
Foreman Building Works – 10 marks
i) CV in required format (2marks) ii) Qualification: Diploma in Civil Engineering (3marks) iii) General Experience of 8 yrs (2marks) iv) Specific Experience of 3 yrs (3 marks)
25 Marks
Only Bidders meeting the Minimum Technical Score of 70% shall proceed to Financial Evaluation stage
B FINANCIAL EVALUATION Financial evaluation will be carried out on Least Cost Basis (LCB)
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C. FINANCIAL EVALUATION CRITERIA
Kenya Railways will make award to the lowest evaluated tender. That is the
lowest priced tender meeting all the Mandatory and Technical Requirements. Bids that pass the Technical Evaluation shall be subjected to the Financial Evaluation in two stages, as follows: -
(1) Tender Sums; and
(2) Tender Rates and arithmetic Errors. 1. Tender Sums 2. Tender Rates Evaluation of the tender rates will constitute examination of (i) pricing consistency (same rates for similar items, price distribution amongst sections, (ii) reasonableness of pricing (comparison with prevailing market levels, inclusion of taxes [VAT, etc] in the rates); and (iii) Free from arithmetic errors. The bidders who pass the test of Tender price consistency and reasonableness, shall finally be graded in terms of their submitted tender sums. The lowest bid in this group shall be the lowest evaluated price as per Section 66(4) of the Public Procurement & Asset Disposal Act 2015
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SECTION VI: TECHNICAL SPECIFICATIONS
The works shall be executed in accordance with the following specifications and Manuals:
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GENERAL SPECIFICATIONS PART I
BUILDERS WORKS
71
BUILDERS WORKS
SPECIFICATION OF WORKMANSHIP AND MATERIALS
GENERAL
SCOPE OF WORKS
The earthworks to be executed under the Contract comprise: -Clearing of the site. -Grubbing and grading of the pavement and construction zone. -Fill up to formation level for subbase, and for topsoil and backfilling around the foundations as specified on the drawings or directed by the Engineer. -Haulage and disposal of excess excavated material. -Supply and transport of imported filling.
SETTING OUT - LEVELLING - ORIGINAL POINTS AND LEVELS
Before the works commence, the Contractor shall proceed to set ou t the various subgrades and base lines, at his own cost and subject to the approval of the Consultants.
If, for whatever reason, the nominal levels of the reference marks are modified, the Contractor shall make the necessary changes and have them approved by the Engineer.
EXCAVATION AND EARTHWORKS
STRUCTURES ENCOUNTERED DURING EXCAVATION WORK
No brickwork, pipes, etc. encountered during the excavation may be demolished until an enquiry has demonstrated that these structures or
installations do not form part of a privately or publicly owned or functioning installation.
The Contractor shall submit for approval documents and drawings indicating all the items encountered during excavation, such as old brickwork, pipes etc.
Demolition of structures encountered during the excavation will be paid for on presentation of documents to be approved.
MAINTENANCE OF SUBBASES, BASES AND SITE ROADS
For the whole duration of the work and until the taking over, the Contractor shall take special care of the subbases, bases and their shoulders. He shall take all necessary steps to avoid that they are damaged either as a consequence of the work or by heavy rain or similar.
During backfilling procedures the Contractor is obliged to carry out the work in an appropriate manner and take the necessary measures to protect the backfilling material.
The Contractor alone is responsible for whatever damage may befall the subbases and bases and he is obliged to see their repair and maintenance at his own cost.
DEMOLITION OF EXISTING CONSTRUCTIONS
These have been taken provisionally under the measured work.
STRIPPING OF TOP SOIL
Stripping shall mean digging away the top soil and putting this soil aside for later use or haulage of this material from the site.
In principle the stripping work shall be carried out by means of a bulldozer and the top soil shall be deposited in recommended places approved by the Architect/Engineer and easily accessible for loading vehicles.
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Where the stripped topsoil consists of dark grey clay with occasional phonolite fragments, the clay soil, named cotton soil, is highly expansive and it is absolutely vital that this clay soil be removed underneath all structures and paved areas and taken to tip.
A stockpile of top soil if approved for future use shall be kept for later covering of non-paved areas in a thickness of 200 mm.
CLASSIFICATION OF EXCAVATED MATERIAL
Excavated materials shall be classified as follows and earthwork in each of the classes measured separately.
ORDINARY SOIL
By ordinary soil is understood: such material as does not necessitate the use of a ripper, nor the use of explosives. Generally any material which yields to the ordinary application of shovel or pick axe such as stiff clay, murram, sand, gravel including boulders with a volume not larger than 0.5 cubic meter.
Boulders larger than 0.5 cubic metre shall be classified as soft or hard rock as defined below.
SOFT ROCK, HARD SOIL
By this is meant: such material as is not covered by the category above, but which can normally be dug out by means of a ripper with one tooth mounted on a tractor with three hundred and fifty (350) H.P. or more. This material shall include coral rock, highly consolidated and strongly cemented murram and gravel mixed with boulders of hard rock not larger than 0.5 cubic metre.
HARD ROCK
By this material is meant such material as cannot be removed by ordinary earthwork machinery or by the ripper. It shall comprise boulders 0.5 cubic meter in volume or greater and all rock in ledges, bedded deposits, and conglomerate deposits so firmly cemented as to
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present all the characterizes of solid rock. This soil type involves loosening and breaking by blasting and digging out and removal of the thus loosened ground.
Rock, boulders or gravel required by the contractor for future use in the works shall be neatly stacked where required or as otherwise approved or directed.
PROTECTION OF PIPES, CABLES, ETC.
Before commencing works which include excavations or ground levelling by manual or mechanical excavation the Contractor shall at his own expense ascertain in writing from the Post Office, Kenya Power & Lighting Co. Ltd., Engineer's Department (Water and Sewers Section) and all other Public Bodies, Companies and Persons who may be affected, the position and depth of their respective ducts, cables, mains or pipes and appurtenances. He shall thereupon search for and locate such services.
The Contractor shall at his own expense effectually prop, protect, underpin, alter, divert, restore and make good as may be necessary all pipes, cables or ducts, poles or wires and their appurtenances disturbed or damaged during the progress of the works, or consequence thereof.
Except that such services as required to be removed or altered by virtue of the layout of the permanent work and not the manner in which the work is carried out, shall be so removed or altered at the expense of the Employer.
The Contractor shall be liable for the cost of repairs to any services damaged as a result of carrying out the Works and shall further be liable for any damage which may be shown during the period of maintenance, to have arisen through the execution of these works.
EXCAVATION BELOW REQUIRED DEPTH
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Should any excavations be made below the levels shown or required to obtain a solid bottom, the Contractor shall, at his own expense, satisfactorily fill in such extra depth and width with concrete similar to that described for foundations or as directed by the Architect/Engineer.
BACKFILLING AROUND CONSTRUCTIONS
Backfilling underneath future foundations shall be performed with lean concrete Class 15. For other backfilling materials as stated in clause above shall be used and compaction shall be in as described below.
Where the CBR value of the fill material obtained from general excavation is less than 8% at BS Compaction after 48 hours soaking, then the Engineer shall instruct the Contractor to provide selected fill in the upper layer or layers of the embankment. The thickness of the selected fill material shall be determined by the Engineer.
PLACING AND COMPACTION OF BACKFILL The backfill shall be filled in and compacted methodically; it shall be spread in layers of max 200 mm thickness. If the Contractor has powerful compaction (vibration roller) equipment at his disposal, this layer may be increased to 400 mm on the written approval of the Engineer.
If the moisture content is inferior to the optimum value, the Contractor shall sprinkle the backfill with water. Also, he shall pay special attention to the compaction procedures for the areas along the edges. For this purpose he must give the edges a little excess fill so as to produce a slight inclination towards the middle of the backfilled area. Compaction of the shoulders may be carried out with a vibration roller whose centre of gravity can be shifted towards the middle of the backfilled area.
During the placing and compaction of the backfill the Contractor shall make sure that the works in reinforced concrete are well protected so that no harm befalls them.
In forming embankments, the Contractor shall make due allowance in height and width for consolidation and shrinkage. On the completion of
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the Contract, the levels, width and dimensions of the finished surfaces of embankments shall correspond to the levels and dimensions shown on the Drawings.
HARDCORE FILLING Hardcore filling under floors etc. shall be good hard stone ballast or quarry waste to the approval of the Architect and or Engineer broken to pass not greater than a 150 mm ring or to be 75% of the finished thickness of the layers being compacted whichever is the lesser. Hardcore shall be free from all weeds, roots, vegetable soil, clay, black cotton soil or other unsuitable materials.
It shall be well graded with smaller stones and fine materials to give a dense compact mass after consolidation. Sufficient fine material shall be added to each layer to give gradation of material as necessary to obtain a solid compact mass after rolling. Hardcore filling is to be laid in layers each of a consolidated thickness not exceeding 200 mm. Each layer shall be compacted by at least 8 passes of a 10 ton smooth wheeled roller or a 2 ton vibrating roller until all movements ceases. Sufficient water is to be added to obtain maximum compaction to the Architect's approval.
To each layer a 25 mm thick layer of sand complying with the specification for fine aggregate for concrete shall be spread over the surface and forced into the hardcore by the use of a vibrating roller weighing not less than 2 tons, this operation should be carried out when the materials are dry and repeated whilst the sand is well watered; should all the sand be absorbed the Architect and or Engineer may require a further layer to be applied and the process repeated.
The top surface of the hardcore shall be levelled or graded to falls as required, and shall then be blinded with a layer of similar material broken to 25 mm. gauge and surfaced with 25 mm. layer of stone dust, watered and consolidated by an 8 to 10 ton smooth wheel roller. The surface so obtained shall be to the Architect's and or Engineer's approval.
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SPECIFICATIONS FOR CONCRETE WORK
Codes of Practice
All workmanship, materials, tests and performances in connection with the reinforced concrete shall be in conformity with the latest edition of the British Standard for concrete works (BS 8110 parts 1 & 2, BS 8004, BS 8007) and any other approved Local and International Standards. Where inconsistency exists between these preambles and these Standards, the Contractor shall notify the Engineer in good time for his clarification as to which of the two shall prevail. Such Clarification shall not have cost implications on the Contract.
Supervision
A competent person approved by the Engineer shall be employed by the Contractor whose duty will be to supervise all stages in the preparation and placing of the concrete. All cubes shall be made and site tests carried out under his direct supervision, in consultation with the Engineer.
As and when required by the Engineer the Contractor shall prepare and submit, before commencing the work, a time chart (additional to the general programme) detailing the various operations for concrete works.
Contractor's Plant, Equipment and Construction Procedures
Not less than 30 days prior to the installation of the Contractor's plant and equipment for processing, handling, transportation, storing and proportioning ingredients, and for mixing, transporting and placing concrete, the Contractor shall submit drawings for approval by the Engineer, showing proposed general plant arrangement, together with a general description of the equipment he proposes to use.
After completion of installation, the operation of the plant and equipment shall be subject to the approval of the Engineer.
Where these Preambles, the Bills of Quantities or the Drawings require
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specific procedures to be followed, such requirements are not to be construed as prohibiting use by the Contractor of alternative procedures providing these have been approved by the Engineer in advance. Approval of plant and equipment or their operation, or of any construction procedure, shall not operate to waive or modify any provision or requirements contained in the Preambles governing the quality of the materials of the finished work.
Levels and Foundations
The foundations of the Works shall be carried down to depths as may be directed by the Engineer and they must be cut as nearly to the size of the concrete as possible and the vacant spaces between the concrete and the solid ground excepting where otherwise shown must be carefully filled in as directed by the Engineer.
All temporary timber shall be removed but should any timber be left in or should any other work be done beyond that specified, it will be at the Contractor's own cost.
Tolerances
On all setting out, dimensions of six meters and over, a maximum noncumulative tolerance of plus or minus 6mm will be allowed. On all setting out, dimensions under six meters, a maximum noncumulative tolerance of plus or minus 3 mm will be allowed. On the cross sectional dimensions of structural members, unless otherwise required by the Drawings, a maximum tolerance of plus or minus 3 mm will be permitted.
The top surface of concrete floor slabs and beams shall be within 6 mm of the normal level and line shown on the Drawings. Columns shall be truly plumb and noncumulative tolerance of 3 mm in each storey and not more than h/3000 out of plumb in their full height will be permitted. The Contractor shall be responsible for the cost of all corrective measures required by the Engineer to rectify work which is not constructed within the tolerances set out above.
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Materials Generally
All materials which have been damaged, contaminated or have deteriorated or do not comply in any way with the requirements of these Preambles shall be rejected and shall be removed immediately from the Site at the Contractor's own expense. No materials shall be stored or stacked on suspended floors without the Engineer's prior approval.
Samples and Testing
The Contractor shall provide on the site, equipment, staff and labour for carrying out the sampling and testing and shall carry out any or all of these tests at such times and with such frequency as may be requested by the Engineer.
All equipment shall be calibrated and checked from time to time by the relevant Government authority or/and as the Engineer may direct.
The contractor shall provide all samples required by the Engineer as soon as possible after the contract is let. No deliveries in bulk shall be made until the samples are approved by the Engineer. All condemned material shall be removed from the site within 24 hours.
Frequency of tests and number of samples required shall be governed by the results of previous tests, the quality of materials revealed during the tests and the uniformity of that quality. Should it become evident that the quality of concrete is deteriorating; the Engineer may require additional samples to be taken and test cubes to be made and tested to determine the cause?
If these tests show that any of the materials or construction do not comply with the requirements of this specification, the Contractor will be responsible for the costs of further tests and the replacement of defective materials and/or construction.
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Cement
Cement unless otherwise specified shall be Ordinary Portland Cement of a brand and source approved by the Engineer and shall comply with the requirements of BS 12. A manufacturer's certificate of test in accordance with BS 12 shall be supplied for each consignment delivered to the Site.
Should the Contractor require tousle cement of Rapid Hardening variety, he shall submit his proposals to the Engineer along with any cost implications on the project for his approval. Any additional cost that may be caused by the use of Rapid Hardening cement shall be borne by the Contractor.
Cement may be delivered to the Site either in bags or in bulk.
If delivered in bags each bag shall be properly sealed and marked with the manufacturer's name and on the Site is to be stored in weatherproof shed of adequate dimensions with a raised floor. Each consignment shall be kept separate and marked so that it may be used in the sequence in which it is received. Any bag found to contain cement which has set or partly set, shall be completely discarded and not used in the works. Bags shall not be stored in stacks more than 2.1 meters in height.
No cement which has been kept on site in bags for more than 3 months shall be used in the works.
If delivered in bulk the cement shall be stored in a weatherproof silo either provided by the cement supplier or by the Contractor but in either case the silo shall be to the approval of the Engineer.
Aggregates
Aggregates shall conform to the requirement of BS 882 and all the
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proposed sources, types and grading test results of all aggregates are to be approved in all respects by the Engineer before work commences.
The grading of aggregates shall be one within the limits set out in BS 882 and as later specified and the grading, once approved, shall be adhered to throughout the Works and not varied without the approval of the Engineer. Fine aggregates shall be clean, coarse, siliceous sand of good, sharp, hard quality and shall be free from lumps of stone, earth, loan, dust, salt, organic matter and any other deleterious substances. It shall be graded within the limits of Zone 1 or 2 of Table 2 of BS 882.
Coarse aggregate shall be good, hard, clean, approved blackstrap or similar stone, free from dust, decomposed stone, clay, earth matter, foreign substances or friable thin elongated or laminated pieces. It shall be graded within the limits of Table 1 of BS 882 for its respective nominal size.
If in the opinion of the Engineer the aggregate meets with the above requirements but is dirty or adulterated in any manner it shall be screened and/or washed with clean water at the Contractor's expense.
Aggregates shall be delivered to the Site in their prescribed sizes or gradings and shall be stockpiled on paved areas to boarded platforms in separate units to avoid intermixing. Onnoaccountshallpremixed coarse aggregates be brought to the batching plant. On no account shall aggregates be stockpiled on the ground.
The Engineer shall be entitled to require a Certificate from an approved testing laboratory in connection with each source of fine and coarse aggregates (including sand) showing that materials comply with the specification. Samples shall be subjected to such tests and at frequencies as determined by the Engineer. All such testing shall be carried out at the Contractor's expense.
Water
The water used for mixing concrete shall be from an approved source,
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clean, fresh, and free from harmful matter and comply with the requirements of BS 3148.
Admixtures
Before approval for the use of a proprietary admixture is given, the Contractor shall satisfy the Engineer as to its suitability for the work and its compatibility with the cement it is intended to complement.
Expansion Joint Fillers
Expansion joint filler shall be "Flexcell" as manufactured by Expandite Ltd. or "Rexilex" as manufactured by Evomastic Ltd., or equivalent and approved filler.
Joint Sealant
Sealants shall be polysulphide based "Plastic" or "Seelastic" as described, both manufactured by Expandite Ltd. or equivalent, applied in accordance with the manufacturer's printed instructions and prices shall include for temporary battens or fillets and afterwards withdrawing to form groves as necessary.
"Seelastic" shall be applied by gun and where more than 12 mm deep shall include filling with loose packing yarn to within 12 mm from outer face.
"Plastic" shall be applied hot. With the Engineer's approval Pole mastic fillers of the appropriate grade as manufactured by Evomastics Ltd., may be substituted for "Seelastic".
On no account shall soft board materials be used as joint fillers.
Concrete Mixes
All structural concrete shall consist of laboratory designed mixes. The weights of cement, fine, coarse aggregates and water (and plasticiser where required) to be used in the designed concrete mixes shall be
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those giving one cubic metre of mixed concrete. Each design mix (for each class of structural concrete) shall be submitted to the Engineer along with at least 8 laboratory test results (4 No. 7 days and 4 No. 28 days) for his approval The design mixes and the accompanying test results shall be sent in their original form directly to the Engineer with a copy to the Contractor. No photocopies shall be accepted. Once approved these design mixes shall be used in the preliminary stage of works.
Only the 28 day test results shall form the basis of assessment for the preliminary and works cube results but the Engineer may use the 7 day test results to determine the quality of concreting at his discretion.
Structural Concrete Strengths At Preliminary Works Stage
For the purpose of this Contract, structural concrete shall mean concrete for which the specified characteristic cube strength is equal to or higher than 20N/mm².
The concrete mix shall be designed to attain a mean strength greater than the characteristic strength by at least the current margin. The current margin shall be taken as the smaller of the value resulting from (1) or (2) below.
(1) For at least 40 separate batches of concrete of identical proportions of similar materials produced over a period of between 5 days and 60 days using the same plant under similar supervision and procedures.
Current Margin = 1.64 times the standard deviation but not less than 7.5N/mm²
(2) For cube tests on at least 100 batches as described in (1) produced over a period not exceeding 12 months.
Current Margin = 1.64 times the standard deviation but not less than 3.75N/mm² for concrete grade 20 and above.
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Where there is insufficient data to satisfy (1) and (2), the current margin for the initial mix design shall be taken as 10N/mm² until sufficient data is available.
Testing of concrete at preliminary stage shall continue until the Engineer is fully satisfied that the concrete mix has met all the requirements outlined in this section.
Structural concrete shall satisfy the above requirements for the characteristic strength at 28 days shown in the table below.
Concrete Strengths in (N/mm²)
Age Grade 45
Grade 40
Grade 35
Grade 30
Grade 25
Grad e 20
7 Days 30.0 27.0 23.5 20.0 16.5 13.5
Characteri stic strength at 28 days
45.0 40.0 35.0 30.0 25.0 20.0
The strength at 7 days shall only be indicative and unless the Engineer otherwise agrees, it shall not form the basis of approval for design mixes.
Quality Control at Works Stage
Once the concrete mix is accepted from preliminary to works stage, the principal basis of control shall be by analysis of the cube test results at 28 days.
Cube test results shall be examined individually in 10 consecutive sets of four. The standard deviation and mean strength of each set shall be calculated. The concrete mix proportions shall only be acceptable if all of the following requirements are complied with:
(i) Not more than two results in 40 are less than the characteristic crushing strength.
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(ii) No value of the average for any set of four results shall be less than the characteristic strength plus one-half of the current margin.
(iii) When 40 No. have been obtained and the mean strength and standard deviation are calculated, the mean strength minus 1.64 times the standard deviation shall be greater than the characteristic strength.
Where the results do not conform to the above requirements the following action shall be taken:
Adjustments to the mix to obtain strength required. In the case where any result is less than 85% of the characteristic strength the structural implications shall be determined and any necessary remedial action carried out shall be at Contractor's cost.
Proportions of Concrete Works
(i) All structural concrete shall be proportioned in weight using weigh batching machines of an approved type (to BS 1305) and shall be properly maintained and checked for accuracy to the requirements of Factories Inspectorate and at such intervals as required by the law and/or as the Engineer shall direct.
The quantity of cement shall be measured by weight. Where delivered in bags, each batch of concrete is to apply one or more bags of cement.
(ii) For Non structural concrete volume batching may be used as indicated below.
Class of Concrete 15 10 Nominalmixbyvolume 1:3:6 1:4:8
Cubic meters of fine aggregate per 50 kg. bag of cement 0.12 0.16
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Cubic meters of coarse aggregate per 50 kg. bag of cement 0.24 0.32
Max. size of coarse aggregate 20 mm 20 mm
Where batching is by volume, approved gauge boxes of such a size as will give the correct proportions shall be used, and full account shall be taken of bulking due to high moisture content.
Ready Mixed Concrete
Where the Contractor desires to use ready mixed concrete prepared outside the site, he shall submit a written request to the Engineer for his approval. In his request, the Contractor shall attach a detailed proposal showing the logistics of carrying out such an exercise.
The Engineer shall give his written consent only after satisfying himself with the adequacy of the Contractor's proposals as far as specifications and logistics are concerned. The Engineer may demand particular conditions be fulfilled before granting the permission (A sample of "Delivery Ticket" for ready-mix concrete is attached at the back of this specification).
WATERPROOFING CONCRETE
Chemical Treatment for Waterproofing
Waterproof Concrete
Where waterproof concrete is specified, Sealocrete "Sealopruf Integral Waterproofing Compound" and "Sealoplaz Concrete Plasticiser" or similar approved are to be added to the mixing water strictly in accordance with the manufacturer's instructions and at the rate of 500 cc and 125 cc respectively to each 50kg bag of cement to which the aggregates have already been added and mixed. Not more that 22.5 to 24.75 liters of water per 50 kg bag of cement are to be used unless otherwise approved by the Engineer.
Surface treatment for waterproofing
Where specified surface treatment with "Sealocrete Super coat Water proofer" etc. shall be applied to concrete or blockwork surfaces strictly in accordance with the manufacturer's instructions. The surfaces must be well wire brushed to remove dirt, efflorescence, adhering mortar and all foreign matter. It shall then be cleaned with fresh water. When absolutely dry a generous coat of Sealocrete Super coat shall be applied by brush or spray gun. Surface so treated shall be protected from damage or staining as described elsewhere.
Physical barriers for waterproofing
Where specified, physical barriers shall consist of the following:
Mastic Asphalt
This shall be laid in layers of maximum thickness 10mm each. The Materials and workmanship shall comply to CP. 102:1973.
Rubber Membrane
This shall consist of preformed laminated membrane comprising an elastomeric self-adhesive rubber/bitumen compound and robust polythene sheet such as Bituthene 1000, as produced by SERVICISED LIMITED or other similar approved material. The membrane shall be stored handled and laid onto the elements to be protected strictly in accordance with the manufacturer’s specifications and under the supervision of one of their approved representatives all to CP. 102:1973. Special precautions shall be taken at the interface of this material and mastic asphalt.
Polythene Sheeting
This shall be either gauge 500 or 1000 laid, lapped and jointed (including taping) to manufacturer’s specifications or as instructed by the Engineer.
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Water bars
Only approved water bars shall be incorporated in the structural concrete works and these shall be provided in the positions indicated on the drawings or at other alternative positions approved by the Engineer.
Joints shall be heat welded in accordance with the manufacturer's instructions and where the water bar is to be fixed vertically, metal clips as manufactured by the supplier of the water bar or of other approved design shall be provided to suspend the water bar from the reinforcement.
Where waterproof concrete is used the Contractor shall adhere strictly to the position and type of construction joints as detailed on the drawings. Any deviation from this procedure or the provision of additional construction joints will require the prior approval of the Engineer and any additional water bar so required will be at the Contractor's expense.
Formwork shall be designed with sufficient timber forms and blocking pieces to support the water bar and to ensure that it is not displaced during concreting. In the case of horizontal joints in vertical walling and similar members the formwork shall be so constructed as to permit the starter or upstand of concrete surrounding the lower half of the water bar to be poured in the same operation as the slab or other concrete from which it springs. Formwork to walls or similar members where water bar is positioned at the base of the lift shall have sufficient inspection openings not less than 300 mm square at approximately 150 mm to 300 mm above the level of the water bar to permit checking that the water bar is correctly positioned and not displaced during concreting.
Through bolts or ties will not be permitted in liquid retaining structure or in retaining walls. The Contractor shall use only such bolts or ties as are capable of being removed in part so that the portion remaining embedded in the concrete shall be between the specified thicknesses of cover to the reinforcement.
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No concreting will be permitted to portions where upstand starters form an integral part until the formwork to the starter has been fixed and approved. No through holes shall be permitted in basement retaining walls.
The Contractor shall provide the following furniture and equipment for setting up his laboratory to be used in carrying out control tests on the site.
Work Cube Tests
Work cubes are to be made at intervals as required by the Engineer and the Contractor shall provide a continuous record of the concrete work. The cubes shall be made in approved 100 or 150 mm moulds as required by the Engineer in strict accordance with the Code of Practice.
At least four cubes shall be made on each occasion, from different batches, the concrete being taken from the point of deposit.
Frequency of the tests and the number of samples required will be governed by the results of the previous tests, the quality of the materials revealed during the tests, and the uniformity of the quality. Should it become evident that the quality of the concrete is deteriorating the Engineer may require additional samples to be taken and test cubes to be made and tested to determine the cause.
Each cube shall be marked with a distinguishing number (numbers to run consecutively) and the date, and a record shall be kept on Site giving the following particulars:
(a) Cube No.
(b) Date and time made
(c) Temperature and weather conditions
(d) Location in work.
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(e) 7day Test
Date: .......................................
Strength ..................................
(f) 28day Test
Date: .......................................
Strength ..................................
Cubes shall be forwarded, carriage paid, to an approved Testing laboratory in time to be tested two at 7 days and two at 28 days. No cube shall be dispatched within 3 days of casting.
Authentic copies of all Work Test results shall be forwarded to the Engineer directly from the testing laboratory and one shall be retained on the site. The test certificates shall indicate all properties as required by BS 1881.
If the strengths required above are not attained, and maintained throughout the carrying out of the Contract, the Contractor will be required to increase the proportion of cement and/or substitute better aggregates so as to give concrete which does comply with the requirements of the Contract. The Contractor may be required to remove and replace at his own cost any concrete which fails to attain the required strength as ascertained by Work Cube Test.
The Contractor must allow in his rates for concrete test cubes for all expenses in connection with the preparation and conveyance to the Testing Laboratory and testing of test cubes and no claim in respect of his failure to do so will be entertained.
Mixing of Concrete
The concrete shall be mixed only in approved power driven weigh batch mixers of a type and capacity suitable for the work. The batching plant shall have a reserve capacity of at least 30% over and above the expected maximum demand.
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The weigh batch mixer shall be equipped with an accurate water measuring device. All materials shall be thoroughly mixed dry before the water is added and the mixing of each batch shall continue for a period of not less than two minutes after the water has been added and until there is a uniform distribution of the materials and the mass is uniform in colour.
The entire contents of the mixed drum shall be discharged before recharging. The volume of mixed materials shall not exceed the rated capacity of the mixer. Whenever the mixer is started, 10% extra cement shall be added to the first batch and no extra payment will be made on this account.
As a check on concrete consistency slump tests may be carried out and shall be in accordance with BS 1881. The Contractor shall provide the necessary apparatus and allow for the cost of such test. The slump of the concrete made with the specified water content, using dry materials, shall be determined and the water to be added under wet conditions shall be so reduced as to give approximately the same slump.
Transporting Concrete
The concrete shall be mixed as near to the place where it is required as is practicable, and only as much as is required for a specified section of the work shall be mixed at one time, such section to be commenced and finished in one operation without delay.
All concrete must be efficiently handled and used in the Works within twenty (20) minutes of mixing. It shall be discharged from the mixer direct either into receptacles or barrows and shall be distributed by means which do not cause separation or otherwise impair the quality of the concrete. Approved mechanical means of handling will be encouraged, but the use of chutes for placing concrete is subject to the prior approval of the Engineer.
Where approval is obtained for concrete to be conveyed by chutes, these shall have a slope (not exceeding 1 vertical to 2 horizontal) such as to ensure a continuous flow of concrete. Additional water
shall not be introduced to assist the flow.
Where approval is obtained for pumping the concrete, the pump manufacturer’s recommendations shall be followed. The pumps used shall be of adequate capacity and power to ensure delivery of a continuous supply. The Contractor shall provide adequate alternative arrangements for transporting concrete including standby pumps in case of a breakdown of the pumping equipment.
No relaxation of this specification on pumped concrete will be permitted. In particular, attention shall be paid to the proper grading of aggregates to prevent bleeding and/or segregation during pumping operations. The inclusion of admixtures to improve the flow characteristics of the concrete will only be permitted where it can be shown that they do not adversely affect the concrete.
Proper bridging arrangements for traffic over reinforcement shall be provided so that the reinforcement is not distorted, damaged or displaced.
Placing Concrete
No concrete shall be placed before approval by the Engineer’s representative.
Any accumulation of set concrete on the reinforcement shall be removed by wire brushing before further concrete is placed.
Care shall be taken that the concrete is not disturbed or subjected to vibrations and shocks during the setting period.
Mixing machines, platforms and barrows shall be clean before commencing mixing and be cleaned on every cessation of work.
Where concrete is laid on hard-core or other absorbent materials, the base shall be suitable and sufficiently wetted before the concrete is deposited.
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Concrete shall be placed from a height not exceeding 1.5 m directly into its permanent position and shall not be worked along the shutters to that position. Unless otherwise approved, concrete shall be placed in a single operation to the full thickness of slabs, beams and similar members, and shall be placed in horizontal layers not exceeding 1.5 m deep in walls and similar members.
Concrete in columns may be placed to a height of 4.0 m with careful placing and vibration and satisfactory results. Where the height of the column exceeds 4.0 m suitable openings must be left in the shutters so that this maximum lift is not exceeded. The bottom 500mm must first be thoroughly compacted before more concrete is added as the vibrator is gradually withdrawn.
Tops of lifts in walls and columns shall be finished level and well compacted so that minimal preparation of the next lift is required.
Concrete shall be placed continuously until completion of the part of the work between construction joints as specified hereinafter. If stopping of concreting be unavoidable elsewhere, a construction joint shall be made where the work is stopped. A record of all such joints must be made by the Contractor and a copy supplied to the Engineer.
Wet Weather Concreting
Concreting during periods of constant rain shall not be permitted unless aggregate stockpiles, mixers and transporting equipment and the areas to be concreted are adequately covered.
Hot Weather Concreting
Concreting shall not be permitted if its temperature at placing is in excess of 38ºC. In order to maintain the temperature of the concrete below this value the following precautions shall be taken wholly or in part as instructed by the Engineer;
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(i) All aggregate stockpiles, water lines and tanks as well as the mixer shall be protected from the direct rays of the sun;
(ii) Coarse aggregate shall be cooled by constant watering where possible;
(iii) Mixing water shall be cooled by the addition of ice to the storage tanks where necessary;
(iv) Rapid hardening cement shall not be used; (v) Where the above precautions are inadequate, concreting shall
be carried out during the cooler parts of the day or night as may be directed by the Engineer.
When the air temperature is above 20ºC loss of mixing water by evaporation shall be considered in arriving at the amount of water to be added to the mix. In order to maintain the water/cement ratio within permissible limits an approved water reducing agent shall be included in the mix.
The maximum water/cement ratios may be increased with the Engineer's permission during mixing, but on no account shall water be added to concrete directly or indirectly once it has left the mixer.
In order to reduce premature drying of the concrete during transporting and placing, all chutes, formwork and reinforcement shall be cooled by watering when possible, or shall otherwise be protected from the direct rays of the sun. Any water so used shall be removed by jetting with compressed air before placing the concrete in close contact.
As soon as possible after concreting, the formwork shall be stripped and the surface of the concrete shall be treated in accordance with the requirements stated elsewhere.
Where drying winds are encountered, wind shields shall be positioned as directed by the Engineer to protect exposed surfaces of the curing concrete.
Continuous Pour in Concrete
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Where the Contractor desires to use continuous concreting method in large sections (rafts and walls), he shall submit a written request to the Engineer for approval. In the request he shall attach details which shall include but not be limited to the following:
Total amount of concrete to be placed in the `shift'. Stock of approved concrete materials on site. Capacity of the batching plant. Number and type of truck mixers to be deployed for the exercise and movement logistics. Number of skilled and other manpower to be deployed for the exercise in shifts. Number and capacity of plant to be used in placing concrete (pumps, vibrators, buckets, etc.). Method(s) of monitor and dealing with the heat of hydration. Details of protection against rain and floodwaters and how to cope with it.
The Engineer shall consider the above details and other parameters (e.g. weather, satisfactory records of cube test results, availability of adequate working section where reinforcement placement and the necessary formwork have been approved etc.) before making his decision. The Engineer may order that additional concrete cube moulds be made available as well as arrangements be made for cube crushing with an approved laboratory to cope with the increased demand.
The Engineer may order that the concreting works be stopped immediately if in his opinion the quality of the works is threatened for whatever reason.
Special No fines Concrete
No fines concrete for use in subsoil drainage shall consist of a 1:8 cement/aggregates mix by volume. Aggregate shall be 20mm to 10mm graded with no more than 5% passing the 10mm sieve. Only sufficient water shall be added to ensure complete coating of the aggregate.
One half of this water shall be placed into the mixer first, after which
the aggregate and cement shall be admitted. After partial mixing the balance of the water shall be added until a consistency of mix is achieved.
Preliminary tests shall be carried out on the site to prove the suitability of the finished concrete and adjustments made to the proportions and or grading as may be required by the Engineer.
Compaction
At all times during which concrete is being placed, the Contractor shall provide adequate trained and experienced labour to ensure that the concrete is compacted in the forms to the satisfaction of the Engineer.
The Contractor shall ensure that he has at least 30% backup/reserve capacity over and above the maximum expected demand.
Concrete shall not be placed at a rate greater than will permit satisfactory compaction nor to a depth greater than 450 mm before it is compacted.
During and immediately after placing, the concrete shall be thoroughly compacted by means of continuous vibration.
Care shall be taken to fill every part of the forms, to work the concrete under and around the reinforcement without displacing it and to avoid disturbing recently placed concrete which has begun to set. Any water accumulating on the surface of newly placed concrete shall be removed and no further concrete shall be placed thereon until such water is removed.
Internal vibrators shall have a frequency of not less than 7,000 cycles per minute and shall have a rotation eccentric weight of at
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least 0.75 kg with an eccentricity of not more than 15 mm. Such vibrators shall visibly affect the concrete within a radius of 250 mm from the vibrator.
Internal vibrators shall not be inserted between layers of reinforcement less than one and one half times the diameter of the vibrators apart. Contact between vibrators and reinforcement and vibrators and formwork shall be avoided.
Internal vibrators shall be inserted vertically into the concrete wherever possible at not more than 500 mm centres and shall constantly be moved from place to place. No internal vibrator shall be permitted to remain in any one position for more than ten seconds and it shall be withdrawn very slowly from the concrete.
In consolidating each layer of concrete the vibrating head shall be allowed to penetrate and revibrate the concrete in the upper portion of the underlying layer. In the area where newly placed concrete in each layer joins previously placed concrete, more than usual vibration shall be performed, the vibrator penetrating deeply at close intervals along these contacts. Layers of concrete shall not be placed until layers previously placed have been vibrated thoroughly as specified.
Vibrators shall not be used to move concrete from place to place in the formwork.
At least one interval vibrator shall be operated for every four cubic meters of concrete placed per hour and at least one spare vibrator for every three shall be maintained on Site in case of break down during concreting operations.
External formwork vibrators shall be of the high frequency low amplitude type applied with the principal direction of vibration in the horizontal plane. They shall be attached directly to the forms at not more that 1.200 M centres.
In addition to internal and external vibration the upper surface of suspended floor slabs shall be levelled with a tamping or vibrating
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screed prior to finishing. Vibrating elements shall be of the low frequency high amplitude type operating at a speed of not less than 3,000 r.p.m.
Construction Joints
Construction joints shall be permitted only at the positions predetermined on the drawings or as instructed on the Site by the Engineer. In general they shall be perpendicular to the lines of principal stresses and shall be located at points of minimum shear, viz. vertically at, or near, midspans of slabs, ribs and beams.
The position of construction joints, when not shown on the Drawings or otherwise required by this specification, shall be decided on site having regard to the plant and labour made available by the Contractor for the manufacture, placing and compaction of the concrete as well as its curing, the climatic conditions prevailing at the time of concreting, the nature and size of the formwork and the conditions of operations of the work. The contractor shall submit his proposals to the Engineer for his approval before commencing the work.
Suspended concrete slabs are generally to be cast using alternate bay construction in bays not exceeding 15 m in length. No two adjacent bays are to be cast within a minimum period of 48 hours of each other. The joints between adjacent bays are to be in positions agreed with the Engineer.
Under no circumstances shall concrete be allowed to tailoff, but it shall be deposited against stopping off boards.
Before placing new concrete against concrete already hardened, the face of the old concrete shall be thoroughly hacked, roughened and cleaned, and laitance and loose material removed therefrom, and immediately before placing the new concrete the surface shall be saturated with water and covered with a coat of mortar at least 25 mm in thickness composed of cement and fine aggregate in the proportions used in the concrete.
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Curing and Protection
Care must be taken that no concrete is allowed to become prematurely dry and the fresh concrete must be carefully protected within two hours of placing from rain, sun and wind by means of at least three layers of Hessian sacking, white polythene sheeting, or other approved means. This protective layer and the concrete itself must be kept continuously wet for at least seven days after the concrete has been placed. The Contractor must allow for the complete coverage of all fresh concrete for a period of 7 days. Hessian or white polythene sheeting shall be in the maximum widths obtainable and shall be secured against wind. The Contractor will not be permitted to use old cement bags, clear or any other colour polythene sheets, Hessian or other material in small pieces.
Concrete in foundations and other underground work shall be protected from admixture with the falling earth after placing.
Traffic or loading must not be allowed on the concrete until the concrete is sufficiently matured, and in no case shall traffic or loading be of such magnitude as to cause deflection or other movement in the formwork or damage to the concrete members. Where directed by the Engineer props may be required to be left in position under slabs and other members for greater periods than those specified hereafter.
Faulty Concrete
Any concrete which fails to comply with these Preambles, or which shows signs of setting before it is placed shall be taken out and removed from the Site. Where concrete is found to be defective after it has set, the concrete shall be cut out and replaced in accordance with the Engineer's instructions. On no account shall any faulty, honeycombed, or otherwise defective concrete be repaired or patched until the Engineer has made an inspection and issued instructions for the repair.
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On the Engineer's instruction, the contractor shall cut out and replace any concrete in any part of the structure if in the Engineer's opinion;
(a) The concrete does not conform to the specification, or
(b) Deleterious materials or materials which are likely to produce harmful effects have been included in the concrete, or
(c) The honeycombed or damaged surfaces are too extensive, or
(d) The finished concrete sizes are not in accordance with the drawings within permissible tolerances, or
(e) The settingout is incorrect, or
(f) The steel cover has not been maintained, or
(g) The protection, including curing of the concrete during the construction was inadequate resulting in damage, or
(h) Undue deformation of or damage to the works has taken place due to inadequate shuttering or to premature traffic or to excessive loading, or
(i) Any combination of the above points has taken place resulting in unsatisfactory work.
The whole of the cost, whatsoever (including time lost) which may be occasioned by the need to remove faulty concrete shall be borne by the Contractor.
Loading Tests
The Engineer may direct that a loading test be made on the works or any part thereof if he deems such a test to be necessary for one or more of the following reasons:
(a) Failure of "Site cubes" to attain the strength requirements.
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(b) Premature removal of formwork;
(c) Overloading of structure during construction;
(d) Improper compaction of concrete;
(e) Any other circumstances attributable to alleged negligence on the part of the Contractor which in the opinion of the Engineer may result in a structure being of less than the required strength.
If the loading test be ordered to be made solely or in part for reasons (a) to (d) the test shall be made at the Contractor's own cost.
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If the loading test be ordered to be made for reason (e), the Contractor shall be reimbursed for the cost of the test if the result is satisfactory.
Loading tests shall be carried out in accordance with the requirements of BS 8110.
If the results of the test are not satisfactory, the Engineer will direct that the part of the work concerned be taken down or removed and reconstructed to comply with the Specification or that such other remedial measures as he may think fit be taken to make the work acceptable and the Contractor shall carry out such work at his own cost.
The Engineer may also instruct the Contractor before a loading test takes place to take out cylindrical core specimens from the structures concerned and have them tested. The cutting equipment and the method of doing the work shall be to the Engineer's approval. The specimens shall be dealt with in accordance with BS 1881. Prior to testing, the specimens shall be available for examination by the Engineer.
If the cores are ordered to be taken solely or in part for reasons (a) and (d) above, the work involved and the testing shall be made at the Contractor's own cost. If the cores are to be taken for reasons (b), (c) and (e) above, the Contractor will be reimbursed the cost of the work involved and the testing if the loading test described in the previous paragraphs proves to be satisfactory.
No extensions of time shall be granted for any delays or disruption of work caused by these tests.
Steel Reinforcement
The steel reinforcement shall comply with the latest requirements of the following British Standards:
Hot rolled MS for the
reinforcement of concrete BS 4449
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Hot rolled H.Y. steel for the
reinforcement of concrete BS 4449
Cold worked H.Y. steel for the
reinforcement of concrete BS 4461
Hard drawn steel wire BS 4482 Generally high yield, hirib rebars (425 & 460 N/mm²) shall be used for main reinforcement and mild steel round bars (250 N/mm²) for links and ductility for special elements where specified. In addition where so detailed, mild steel deformed bars shall also be used.
The Contractor shall submit a test certificate of the rollings. Reinforcements shall be stored on racks above ground level in covered waterproof sheds to keep away rain water. The sheds shall be well drained to prevent deterioration or contamination from any cause. All reinforcement shall be free from loose mill scale or rust, grease, paint or other substances likely to reduce the bond between the steel and concrete.
Fabric Reinforcement
Fabric reinforcement shall be electrically crosswelded steel wire mesh reinforcement to BS 4483, and of the size and weight specified and made of wire to BS 4482.
Fixing Steel Reinforcement
Reinforcement shall be accurately bent to the shapes and dimensions shown on the Drawings and Schedules and in accordance with BS 4466 and BS 8110. Reinforcement must be cut and bent cold and no welded joints will be permitted unless so detailed or directed by the Engineer.
Reinforcement shall be accurately placed in position as shown on the drawings, and before and during concreting, shall be secured against displacement by using No. 18 S.W.G. annealed binding wire or suitable clips at intersections, and shall be supported by concrete or metal supports, spacers or metal hangers to ensure the correct
position and cover. No part of binding wire shall protrude into the specified nominal cover.
No concreting shall be commenced until the Engineer has inspected the reinforcement in position and until his approval has been obtained. The Contractor shall give two clear days' notice of his intention to concrete to the Engineer. Approval forms shall be submitted in duplicates. (A sample of the format of the Approval form is attached at the back of this specifications).
The Contractor is responsible for maintaining the reinforcement in its correct position, according to the drawings, before and during concreting. During concreting a competent steel fixer must be in attendance on the concreters to adjust and correct the positions of any reinforcement which may be displaced. The vibrators are not to come into contact with the reinforcement.
Where required to support and retain the reinforcement in its correct position, the Contractor shall provide templates, stools or other supports at his own cost.
Unless permitted by the Engineer, welding of bar reinforcement at intersections or for the joining of bars is prohibited. Where permission is granted, welding shall be carried out in accordance with the recommendations of the Institute of Welding for the welding of reinforcement bars.
The Contractor shall provide on-site facilities for cutting and bending reinforcement whether he is ordering his reinforcement bent or not and shall ensure that a token amount of straight bar of each diameter is available on site for bending as and when directed by the Engineer in order that minor modifications may be implemented on site without prior notice.
Bar bending schedules shall be issued to the Contractor at least a month in advance of the actual physical requirement on site. The Contractor is responsible for verifying that he has in his possession the required schedules to meet his programme and shall give the Engineer at least 3 weeks’ notice for any schedules that he requires.
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Splices and Screwed Couplers Where specified in the works, splices and screwed couplers shall be CCL systems type or similar approved and shall be for reinforcement bar sizes 16, 20, 25 and 32.
The relevant certificates of performance shall be submitted to the Engineer for approval. The Engineer may order additional relevant tests be carried out through the Contractor from time to time as a measure of continuous monitoring of quality and performance.
Position and Correctness of Reinforcement
The Contractor shall draw the Engineer's attention in good time if any discrepancies between details on drawings and bar bending schedules occur.
Irrespective of whether any inspection and/or approval of the fixing of the reinforcement has been carried out as above, it shall be the Contractor's sole responsibility to ensure that the reinforcement complies with the details on the drawings or bending schedules and is fixed exactly in position shown therein and in position to give prescribed cover.
The Contractor will be held entirely responsible for any failing or defect in any portion of the reinforced concrete structure and including any consequent delay, claims, third party claims, etc., where it is shown that the reinforcement has been incorrectly positioned or is incorrect in size or quantity with respect to the detailed drawings or bending schedules.
Spacer Blocks
Spacing blocks of approved size and shape made of concrete similar to that used in the surrounding construction and fixed to the reinforcement or formwork by No. 18 S.W.G. wires set into the spacer blocks or other approved means shall be provided where necessary to ensure that the requisite cover is obtained. The
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Contractor is to include for providing sufficient such spacer blocks in his prices for steel reinforcement where such supplier has been nominated. Where composite blocks or other forms of nib construction are used, spacer blocks are to be provided as shown on the drawings. These will generally consist of concrete blocks as described above made to fit the width of the rib less 3 mm to tolerance and with single or double grooves (depending on the number of the reinforcement bars used per rib) in the top surface with wire ties at each grove. The Engineer may direct that special types of spacers (e.g. preformed plastic types) be used in the whole or part of the works, if in his opinion the concrete spacers are not to the required standard.
Nominal Concrete Cover to Reinforcement
Unless otherwise directed the nominal concrete cover to steel reinforcing bars (including links and distribution) in any face shall be:
Foundations against earth face 75 mm
Foundation against blinding
50 mm
Columns (main bars)
40 mm
Beams (main bars) main bar.
30 mm or diameter of
Slabs and Stairs
20 mm
Walls (main bars)
40 mm
The tolerance on placing of bars to achieve nominal cover is +5mm
Fixing Fabric Reinforcement
The fabric shall be free from scale, rust, grease or other substances likely to reduce the bond between the steel and the concrete and shall be laid with minimum 300 mm laps and bound with No. 18
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S.W.G. annealed iron wire.
Projecting Reinforcement
Where reinforcement projects from a concreted section of the structure and this reinforcement is expected to remain exposed for some time, it is to be coated with a cement grout to prevent rust staining on the finished concrete. This grout is to be brushed off the reinforcement prior to the continuation of concreting.
Security Reinforcement
Spiral
Spiral reinforcement where specified in the works shall be Chubb spiral, Agamas or similar approved. It shall consist of steel bars of at least 15mm diameter forming a mattress with pitches not exceeding 125mm, and shall be delivered to the site in preformed 2 row mattress cages of exact and specified dimensions and incorporating appropriate spacer bars to maintain mattress rigidity. When assembled, the cages shall define the outline of the elements to be protected including allowance for openings. The assembling in the works shall be carried out under the supervision of the supplier's approved representative.
Twisted Plates
These shall be chubb tangbars, John Tann bars, Tord bars or similar approved. They shall be made from 3mm thick mild steel plates cut into strips running off a central cord. They shall be transported to the site in flat condition where they shall be twisted into spirals.
The twisting and laying of the units shall be carried out under the supervision of the supplier's approved representative.
Fixtures and Indentations in Concrete
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No openings, chases, holes or other voids shall be formed in the concrete without the prior approval of the Engineer. Details of any fixtures to be permanently built into the concrete including the proposed positions of all conduits 25 mm and over in diameter shall be submitted to the Engineer for his approval before being placed.
Chases, Holes, etc. in Concrete
The Contractor shall be responsible for the coordination with the Electrical and other Subcontractors for incorporating electrical conduits, pipes, fixing blocks,
chases, holes and the like in concrete members as required and must ensure that adequate notice is given to such Subcontractors informing them when concreting members incorporating the above are to be poured. The Contractor shall submit full details of these items to the Engineer for approval before the work is put in hand. All fixing blocks, chases, holes, etc., to be left in the concrete shall be accurately set out and cast with the concrete.
Position of Electrical Conduits
Unless otherwise instructed by the Engineer all electrical conduits to be positioned within the reinforced concrete shall be fixed inside the steel cages of beams and between the top and bottom steel layers in slabs and similar members.
The proposed position of all conduits 25 mm and over in diameter which are to be enclosed in the concrete shall be shown accurately on a plan to be submitted to the Engineer, whose approval shall be obtained before any such conduit is placed.
Formwork
The method and system of formwork which the Contractor proposes to use shall be approved by the Engineer before construction commences. Formwork shall be substantially and rigidly constructed of timber, steel, plastic, precast concrete or other
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approved material.
All timber for formwork shall be good, sound, clean, sawn, well seasoned timber free from warps and loose knots and of scantlings sufficiently strong for their purpose.
Construction of Formwork
All formwork shall be of sufficient thickness and with joints close enough to prevent undue leakage of liquid from the concrete and fixed to proper alignment, level and plumb and supported on sufficiently strong bearers, shores, braces, plates, etc. properly held together by bolts or other fastenings to prevent displacement, vibration or movement by the weight of materials, men and plant on same and so wedged and clamped as to permit easing and removal of the formwork without jarring the concrete. Where formwork is supported on previously constructed portions of the reinforced concrete structural frame, the Contractor shall by consultation with the Engineer ensure that the supporting concrete structure is capable of carrying the load and/or sufficiently propped from lower floors or portions of the frame to permit the load to be temporarily carried during construction.
Soffits for beams and slabs of spans greater than 10m shall be erected with an upward camber of 5 mm for each 3.0 m of horizontal span or as directed by the Engineer, without reducing the depth of the element.
Great care shall be taken to make and maintain all joints in the formwork as tight as possible, to prevent the leakage of grout during vibration.
All faulty joints shall be cuddled to the Engineer's approval before concreting.
The formwork shall be sufficiently rigid to ensure that no distortion or bulging occurs under the effects of vibration. If at any time the formwork is insufficiently rigid or in any way defective the Contractor
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shall strengthen or improve such formwork as the Engineer may direct.
The Contractor's attention is drawn to the various surface textures and applied finishes required and the faces of formwork next to the concrete must be of such material and construction and be sufficiently true to provide a concrete surface which will in each particular case permit the specified surface treatment or applied finish.
All surfaces which will be in contact with concrete shall be oiled or greased to prevent adhesion of mortar. Oil or grease shall be of a nonstinging mineral type applied as a thin film before the reinforcement is placed. Surplus moisture shall be removed from the forms prior to placing of the concrete. Great care shall be taken to avoid oiling or greasing the reinforcement.
Temporary openings shall be provided at the base of columns, wall and beam forms and at any other points where necessary to facilitate cleaning and inspection immediately before the pouring of concrete. Before the concrete is placed the shuttering shall be trued up and any water accumulated therein shall be removed. All sawdust, chips, nails and other debris shall be washed out or otherwise removed from within the formwork. The reinforcement shall then be inspected for accuracy of fixing. Immediately before placing the concrete the formwork shall be well wetted and inspection openings shall be closed. Cement slurry shall be applied to previously casted concrete as necessary to allow for adequate bonding. The erection, easing, striking and removing of all formwork must be done under the personal supervision of a competent foreman, and any damage occurring through faulty formwork or its incorrect removal shall be made good by the Contractor at his own expense.
After removal of formwork, all projections, fins, etc., on the concrete surface shall be chipped off, and made good to the requirements of the Engineer. Any voids or honeycombing shall be treated as described under "Faulty concrete".
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Stripping Formwork
All formwork shall be removed without undue vibration or shock and without damage to the concrete. No formwork shall be removed without the prior consent of the Engineer. The Contractor shall notify the Engineer of his intended removal of any formwork at least two days in advance. The minimum periods that shall elapse between the placing of the concrete and the striking of the formwork will be as follows:
Beam sides, wall and columns (unloaded) 24 hours
Slab soffits (props left under) 3 days
Beam soffits (props left under) 7 days
Removal of props to: (partly subject to 7 days concrete cube strength being
Satisfactory) Slabs 10 days
Beams
14 days
Cantilever beams and slabs
28 days
In continuous spanning slabs or beams, no span shall be depropped until the adjoining spans have been cast and cured for the specified periods.
Stripping and repropping will not be permitted. The striking times indicated herein are for normal conditions and shall be adjusted if:
(a) The span of the structural member under consideration exceeds 6.0m for beam. An additional period of one day for each 500mm of additional span shall then be allowed.
(b) The dead load of the structural member under consideration forms a large proportion of the total design load.
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(c) The setting of the concrete has been retarded for any reason.
(d) Any combination of the above points and other considerations which would call for such a precaution to be taken.
In any case, props shall be left in place in the lower two consecutive floors over which construction loads are expected to be supported.
SURFACE FINISHES
Fair Face Finish
Where fair face finish is specified the concrete shall be brought to a perfectly true smooth and even surface by rubbing with carborundum stone dipped in cement grout. Such work must be commenced within one hour of removing the formwork and be actively and rapidly pursued until completed, the object being to complete the finish as soon as possible after the removal of the shuttering. On no account may such work be postponed to a later stage in the Contract. Fair face surfaces shall be clean, smooth, even true to form and free from all board marks, joint marks, honeycombing, pitting etc. The Contractor is permitted at his own expense to provide smooth lining to the forms which will achieve the required finish without rubbing down. All rubbed down work must be lightly washed with plain cold water at the completion of the Contract, and not before the cement grout used in the finish is at least four weeks old after initial mixing.
Wrought Lined Formwork
The shuttering shall be constructed of wrought tongued and grooved boarding, plywood or blackboard lined with approved laminated plastic sheeting to produce a concrete surface with truly flat surface completely free from all air bubbles, joint marks, honeycomb and other pittances and blemishes to the approval of the Engineer.
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Should the Contractor desire to use alternative materials he should submit his proposals to the Engineer for approval.
Should the Contractor fail to obtain approval and the Engineer subsequently rejects the work, the Contractor will at his own expense carry out all work necessary to attain the approval of the same.
Tamped Finish
Areas so specified shall be finished at the time of casting with a tamped finish to the Engineer's approval produced by an edge board. Board marks are to be made to a true pattern and will generally be at right angles to the traffic flow. Haphazard or diagonal tamping will not be accepted.
Board Marked Finish
Where so directed or measured the finish shall be that of a board marked pattern panels, the boards shall be arranged vertically and of widths and sizes all as detailed on the drawings. All exposed concrete will be left unpainted and therefore every care and attention shall be paid to obtain a satisfactory visual appearance and that maintenance of the same throughout the building operation. The finished surfaces shall be free from blow holes, hungry patches and other blemishes, and a sample panel is to be provided and approved by the Engineer before work commences.
Unless otherwise specified, the formwork shall be rip sawn softwood to the Engineer's approval and shall have a sufficiently strong grain to impart a corresponding pattern on the concrete surface. Unless otherwise approved it shall have four uses only and shall be carefully cleaned from adhering grout after each use. It shall be lightly oiled with an approved nonstinging mould oil.
Vertical Ribbed Finish
Unless otherwise specified, vertical ribbed finish to walls shall comprise 50 x 50 mm concrete projections at 450 mm centres cast
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vertically on the face of wall. All surfaces are to be as described under "Wrought Formwork".
Diagonal Ribbed Finish
Unless otherwise specified, diagonal ribbed finish to walls shall comprise 50 x 25 mm deep concrete projections at 100 mm centres cast at 45 degree angle to the vertical on face of wall. All surfaces are to be as described under "Wrought Formwork".
Chisel Dressed Finish
Where specified a chisel dressed finish is to be carried out on any grade of concrete but not until it is at least 30 days old. The surfaces are to be fully chisel dressed to remove a maximum of 12 mm (average 9 mm) of the surface to expose the aggregate without excessive cracking or breaking thereof.
Where the drawings show details of arises of columns, beams, etc. these are to be preformed with timber fillets set in the formwork, and care must be taken in working up to those to preserve a clean line. For vertical surfaces of walls and columns, particular care must be taken to remove all sharp projections. For beam soffits this requirement is not necessary.
All chisel dressed surfaces are to have the margins chisel dressed by hand for a minimum width of 75 mm commencing from the fillet edge. Thereafter mechanical chisel dressing may be used but the Contractor must ensure that a uniform texture and even plan surface is achieved. The use of pointed steel tools for both hand and mechanical chisel dressing is essential. Upon completion the surfaces are to be thoroughly wire brushed and washed down and protected during the course of construction from damage, dirt, cement grout, etc.
Precast Concrete
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General
Unless otherwise approved by the Engineer, all precast concrete construction shall be carried out on the Site and shall conform to requirements given elsewhere in these preambles.
The maximum size of coarse aggregate in precast concrete shall not exceed 20 mm except for thicknesses less than 75 mm where it shall not exceed 10 mm.
The compacting of precast concrete shall conform with requirements given elsewhere in these preambles except for thin slabs where use of immersion type vibrators is not practicable. The concrete in these slabs may be consolidated on a vibrating table or by any other methods approved by the Engineer.
Steam curing of precast concrete will be permitted. The procedure for steam curing shall be subject to the approval of the Engineer.
The precast work shall be made under cover and shall remain under the same for seven days. During this period and for a further seven days the concrete shall be shielded by sacking or other approved materials kept constantly wet. It shall then be stacked in the open for at least a further seven days to season before being set in position. Where steam curing is used these times may be reduced subject to the approval of the Engineer.
Precast concrete units shall be constructed in individual forms. The method of handling the precast concrete units after casting, during curing and during transport and erection shall be subject to the approval of the Engineer, providing that such approval shall not relieve the Contractor of responsibility for damage to precast concrete units resulting from careless handling.
Repair of damage to the precast concrete units, except for minor abrasions of the edges which will not impair the installation and/or appearance of the units will not be permitted and the damaged units shall be replaced by the Contractor at his own expense.
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Except where precast work is described as "fair face" or as having "exposed aggregate" or terrazzo finish the moulds shall be made of suitable strong sawn timber true in form to the shapes required. Unless otherwise described faces are to be left rough from the sawn moulds.
Where precast work is described as "fair face" the moulds are to be made of metal or are to have metal or plywood linings or are to be other approved moulds which will produce a smooth dense fair face to the finished concrete suitable to receive a painted finish direct and free from all shutter marks, holes, pittances, etc. In his prices for such precast work the Contractor shall include for all rubbing down to produce the finish required, to the satisfaction and approval of Engineer. Where precast work is to have an "exposed aggregate" or terrazzo finish the moulds shall be constructed to the requirements given for moulds for "finished fair" work. The method of achieving the exposed aggregate finish shall be "aggregate transfer" or other approved method.
Precast Concrete Cladding Units
These shall be cast to the general details shown on the drawings. The contractor shall submit working/shop drawings for each type of the cladding panels to the Engineer for approval before he commences casting operations.
The panels shall be cast in special yards and shall be cured adequately before being hoisted into position in the structure, taking care that no parts are broken in the process. The units shall then be joined together with Insitu concrete and flexibly connected to the top and bottom beams to allow for limited movement of the combined unit.
The precast units shall be installed to the lines, grades and dimensions shown on the Drawings or as directed by the Engineer.
Hollow Block Suspended Construction (Composite Floor
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Slab)
Concrete hollow blocks for use in the composite floor slabs shall be of the standard sizes required or as shown on the drawings and are to be of adequate strength to support the concrete during placing and consolidation by vibration. Blocks are to be manufactured in accordance with the procedure specified in BS 6073 and to be of a mix not weaker than 1:4:8 cement: sand: stone using maximum 10 mm size aggregate.
Concrete blocks are to be cured for at least 28 days before use on the Site. During the first seven days of curing, blocks are to be kept permanently damp and protected from exposure to sun and wind.
Concrete blocks are to be well wetted before the pouring of cement. Hollow clay filler blocks for use in the composite floor slabs are to be of the sizes shown on the drawing and to be of adequate strength to support the concrete during placing and consolidation by vibration. They shall be obtained from an approved manufacturer. Before any orders are placed, at least 6 sample clay blocks shall be provided for the approval of the Engineer. Any clay blocks subsequently delivered to Site which in the opinion of the engineer are not of equal standard to the approved samples shall be rejected.
Rejected blocks shall immediately be removed from the Site and shall not be used in the works. Clay blocks are to be full cured before delivery or use on site.
Clay blocks are to be well wetted before pouring of concrete.
Composite Floor Construction
The hollow block floor construction is generally to be as shown on the Engineer’s Drawings.
Care shall be taken in placing blocks to ensure that they are set out in accordance with the details shown on the Drawings and that they run truly in line without encroaching on the width of the in-situ ribs.
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The open ends of hollow blocks, if adjacent to concrete to be place Insitu, are to be plugged or stopped to prevent the concrete from flowing into the void and the Contractor is to include for this in prices.
The Contractor should note that slip tiles are not to be used to the soffits or ribs and he is to take this into consideration in pricing the items of formwork to the soffit of hollow block floor construction.
Before concreting is carried out the blocks are to be thoroughly wetted.
Caret should be taken during concreting that the width of ribs between the rows of blocks and the solid Insitu concrete shown on the Drawings adjacent to supporting beams is not encroached upon by the blocks.
It is essential that the concrete topping be poured at the same time as the ribs between hollow blocks.
Reinforcement shall be positioned accurately with required cover in accordance with the Drawings and using the particular spacing blocks with wire ties as previously described. Spacer blocks shall be provided in ribs at not more than 1.2 m centres. Care must be taken during concreting that the reinforcement is not displaced.
Where holes or services, occur, the necessary holes or pockets shall be accommodated by the replacing of a hollow block by in-situ concrete or the widening of a rib all in accordance with the Engineer’s instructions. Prices for such holes through hollow block construction are to include the re-arrangement or substitution of the hollow block with solid concrete in addition to the actual formation of the hole.
Concrete Surface Beds
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Before placing concrete and where specified or shown on the Drawings a layer of the appropriate gauge polythene or diothene sheeting shall be laid on the blinding above the hard core filling. Minimum 300 mm laps shall be provided at all joints.
The concrete shall be placed as soon as possible after being mixed. In transporting the concrete, adequate precautions shall be taken to avoid damage to the prepared base. The concreting shall be spread to such a thickness that when compacted it shall have the finished thickness as specified or shown on the Drawings. A layer of concrete 25 mm less than the finished thickness shall first be spread and struck off at the correct level to receive the top fabric reinforcement.
The top layer shall then be added. Not more than 30 minutes shall elapse between spreading the bottom layer and the start of compaction of the top layer. The Contractor shall be responsible for maintaining the reinforcement in its correct position during the placing and compaction of the concrete.
The compaction and finishing of the concrete shall be effected by immersion vibrators and a hand or mechanical tamper weighing not less than 10 Kg per meter run and having a tamping edge shod with a steel strip 75 mm wide fixed to a tamper by countersunk screws. Immersion vibrator with "spade" attachments will be permitted. Compaction shall be continued until a dense, scaled surface finish is achieved. Over compaction causing an excessive amount of fines to be brought to the surface shall be avoided.
The surface of the concrete shall be finished to the surface texture specified to the levels, falls and cross falls, as directed or shown on the Drawings and shall be subject to the following tolerances:
The level shall be within + or 6 mm of the levels specified.
The falls shall be within 10% of the falls specified.
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The smoothness shall be such that departures from a 3m straight edge laid in any direction shall not exceed 3mm.
Minor irregularities shall be made good by the use of a steel float but in no circumstances shall mortar be used to make good the surface.
As soon as the surface has been finished, it shall be protected against too rapid drying by means of damp Hessian, white polythene sheeting or other approved means placed carefully on the surface and kept damp and in position for 7 days and the concrete shall be kept wet for a further 21 days. The most critical period is the first 48 hours after placing and curing during that time shall be very thorough.
The Contractor is to obtain the Engineer's approval to the material and method he proposes to use for curing and no concreting will be permitted until sufficient such material is on Site.
Forms shall not be removed from freshly placed concrete until it is at least 24 hours old. Care shall be taken that in their removal no damage is done to the concrete, but should any damage occur the Contractor shall be responsible for making it good.
Expansion Joints in Concrete Surface Beds
Expansion joints shall be positioned and constructed as shown on the drawings. The joints in the surface beds shall be absolutely square and true to line and position.
All joints in surface beds shall be formed to the patterns and shapes to coincide exactly with the joints in the surface finish or as otherwise indicated on the drawings. Formwork shall be manufactured from steel of heavy angle section and be to the Engineer's approval. The Contractor shall submit drawings of the forms he intends to use and obtain the Engineer's approval before fabrication. Panels shall be poured in alternate bays as agreed with the Engineer. No construction joints other than those indicated on
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the Drawings shall be submitted.
Notes Concerning Measurement and Pricing
The Contractor must allow for all costs incurred during the progress of the Contract for complying with the provisions concerning the preparation and use of "Designed mixes" and "weigh batchers" for all structural concrete work.
Absolutely no deviation from the use of "Design mixes and weigh batching machines shall be entertained on the basis of site topography expanse or any other reason whatsoever as the Contractor will have been deemed to have allowed for these in his pricing.
Prices for concrete shall include for mixing and depositing as described or indicated and for hoisting and depositing at the various levels required throughout the building, and shall also include for forming or hacking a satisfactory key for all faces receiving asphalt and plaster work. Prices for slab shall also include for levelling off the surface as described under "Compaction", and all temporary formwork to form construction joints at bay edges.
STRUCTURAL STEELWORK
GENERAL
Steel portal frames, trusses and purlins will be carried out by an Approved Specialist Sub-Contractor.
QUALITY OF MATERIALS AND WORKMANSHIP
The quality of all materials and workmanship used in the execution of the Works shall in any case comply with the requirements of current relevant British Standards and Codes of Practice, including all the latest requirements.
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MATERIALS
All materials shall be of the best quality, free from defects. The materials in all stages of transportation, handling and stacking shall be kept clean and injury from breaking, bending and distortion prevented.
WORKMANSHIP
All work shall be carried out in the most workmanlike manner and strictly as directed by the Engineer.
Welding shall be neatly cleaned off and units shall be pre-fabricated in the workshop wherever possible, the minimum of site welding being employed.
All screwed work shall have full internal and external threads and holes shall have been cleaned off. Countersinking’s must be concentric.
TESTS
The Engineer may at any time require any materials to be tested in accordance with the requirements of the Standards listed above. The cost of all successful tests shall be borne by the Client. The Contractor shall, if required by the Engineer, promptly supply at his own expense test pieces. The cost of tests on materials failing to comply with this standard shall be borne by the Sub-Contractor. If in the opinion of the Engineer, faulty material and/or workmanship has been used in the Works, the Sub-Contractor may be directed to dismantle and cut out the parts concerned and remove them for examination and testing. The cost of dismantling, cutting out and making good to the approval of the Engineer shall be borne by the Sub-Contractor.
FABRICATION
The Standard of works and the general procedure to be followed during fabrication shall be in accordance with B.S. 449. The Sub-Contractor must submit all his shop drawings to the Engineer for checking and approval and must also ascertain all dimensions on the Site prior to commencement of fabrication.
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RELEVANT BRITISH STANDARDS
B.S. 4360 Weldable Structural Steels
B.S. 449 The use of Structural Steel in Building
B.S. 4848 Hot Rolled Structural Steel Sections
B.S. 2994 Cold Rolled Steel Sections
B.S. 1775 Steel Tubes for Mechanical, Structural and General Engineering purposes
B.S. 5135 Metal arc welding of Carbon and Carbon Manganese Steels
B.S. 639 Covered Electrodes for the manual metal arc Welding of Carbon and Carbon Manganese Steels
B.S. 4872 Approval testing of welders when welding procedure is not required.
B.S. 916 Black bolts, screws and nuts, or alternatively;
B.S. 3692 ISO metric precision hexagon bolts, screws and nuts
B.S. 4190 ISO metric black hexagon bolts, screws and nuts
B.S. 3410 Metal black hexagon bolts screws and nuts
B.S. 4320 Metal washers for general engineering purposes
B.S. 4395 High-strength friction grip bolts and associated nuts and washers for Structural Engineering
B.S. 5493 Protective Coating of Iron and Steel Structures against corrosion
B.S. 15Mild steel for general structural purposes
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B.S. 4 p.2Hot rolled Hollow Sections
B.S. 994 Cold Rolled Steel Sections
B.S. 938 General requirements for the Metal Arc Welding of structural steel tubes to B.S. 1775
B.S. 1856 Covered Electrodes for the Metal Arc Welding of Mild Steel.
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CUTTING AND BENDING
All members, plates, brackets, etc., shall be neatly and accurately sheared, sawn, or profiled to the required shape as shown on the Drawings. Where steel is oxy-cut to shape, care shall be taken to preserve the full finished sizes required.
If members or plates are bent or set, the bends or sets shall be correctly made to the radii or angles specified without leaving hammer marks. The material may be heated to permit this. Material that has been heated shall be annealed to approval.
PUNCHING AND DRILLING
Holes for black bolts shall be drilled or punched 2 mm larger in diameter than the bolt size. Holes for high tensile friction grip bolts shall be drilled or sub-punched and reamed to 2 mm larger in diameter than the specified bolt size. All drilled holes shall be parallel-sided and shall be drilled with the axis of the holes perpendicular to the surface. Badly drilled holes shall be reamed out to approval and larger bolts fixed. All rough arises shall be ground off. Holes formed or enlarged by oxy-cutting will not be accepted and must be filled to approval by electric welding and re-drilling.
BOLTING
All bolts used shall be of such length that at least one full thread is exposed beyond the nut after the nut has been tightened. Where a nut or bolthead would bear on an inclined surface, a bevelled washer of the correct shape shall be interposed between the two surfaces. Bevelled washers shall not be allowed to get out of position during fabrication and erection and for this purpose may be spot-welded to the steel surface. Bevelled washers for use with high tensile bolts shall not be welded.
BLACK BOLTS, NUTS AND WASHERS
Black bolts shall comply with the requirements of B.S. 916 (B.S.W.
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threads) or B.S. 4190 (ISO metric threads).
CLOSE TOLERANCE BOLTS
Close tolerance bolts shall conform to B.S. 3692
HIGH TENSILE BOLTS
High tensile bolts shall conform to B.S. 1768 (UNCE and UNF threads)
HIGH TENSILE BOLTS
High strength friction grip bolts shall be :
(a)In accordance with B.S. 4295 (b)Samples of load indicating bolts must be submitted to the Engineer for approval.
RAWLBOLTS
Samples of rawlbolts shall be similarly submitted to the Engineer to approval.
WASHERS
(a) Plain and tapered washers to B.S. 3410 or B.S. 4320 (b) Washers for high strength friction grip bolts shall beappropriate to the type and quality of the bolt specified.
RIVETS
The steel used for rivets shall be in accordance with B.S. 4360 and in the case of high tensile steel rivets shall be so manufactured that they can be driven and the heads formed and the physical properties not impaired.
NAILS AND SCREWS
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Nails and screws shall be of best quality mild steel of lengths and weight approved by the Engineer. Nails shall be to B.S. 1202.
ELECTRIC WELDING
All welding shall be carried out in strict accordance with the requirements of B.S. 5135 and electrodes shall comply with B.S. 639.
Fusion faces shall be free from irregularities such as tears, fins, etc., which would interfere with the deposition of weld metal.
Fusion faces shall be smooth and uniform and shall be free from loose scale, slag, rust, grease, paint and other deleterious material.
All welds shall be of approved type and finished size as specified. Welding shall be carried out in such sequence that minimum distortion of the parts welded results.
Preparation of edges for welding shall be carried out by planning or machine flame cutting. Manual flame cutting will not be permitted.
Parts to be welded shall be maintained in their correct relative positions during welding, preferably by jigs.
Multiple-run welds shall be carried out with each run closely following the previous run but allowing sufficient time for the proper removal of slag.
The Sub-Contractor shall ensure that each run is inspected and any satisfactory weld cut out and remade to approval.
Welds in material 25 mm or greater in thickness shall be made by the Argon arc or similar approval process, and special precautions shall be taken to prevent weld cracking.
Unless otherwise specified, the minimum size of fillet shall be 6 mm.
On completion, welds shall present a smooth and regular finish. Weld metal shall be solid throughout with complete fusion between weld
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metal and parent metal and between successive runs throughout the joint.
Defects shall be cut out and made good to approval in sound weld metal.
The external faces of butt welds are to be ground smooth on completion.
ROLLED SECTIONS
1. All shop connections shall be electric welded or bolted with high tensile bolts.
No bolts used shall be less than 12 mm diameter and no weld less than 40 mm in length. At least two bolts shall be used in connections transmitting loads, unless otherwise indicated by the Engineer.
No weld of less than four times the nominal fillet size shall be deemed capable of carrying load.
Beam to column connection not detailed shall be of "standard" top and bottom cleat connections with the load carried on the bottom cleat. "Standard" web connections shall be used for connecting beams to beams.
Field connections shall be as detailed, i.e. bolted with high tensile or black bolts in drilled holes. Black bolts in punched holes will only be permitted for connections carrying a designed load or connections to timber members.
STRUCTURAL HOLLOW SECTIONS
Hollow sections shall be connected by electric welding unless 54 and Appendix C of B.S. 449.
Butt welds in tension members will not be permitted unless the prior
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approval of the Engineer in writing has been obtained.
Butt welds where permitted, shall be made with the fusion surface of the ends of each member properly prepared and the member properly aligned.
ASSEMBLY
TRUSSES AND PORTAL FRAMES
Trusses and portal frames shall be carefully set out to the dimensions shown on the drawing and cross checked with actual site setting out.
Where it is required that trusses be cambered, such camber shall be provided by bending the bottom chord to an arch or a circle.
Notwithstanding any dimensioned spacing of purlin cleats, the Sub- Contractor shall ensure that purlin cleat spacing is satisfactory for the available stock lengths of roof sheeting. However, the Engineer's approval must first be obtained before any alteration is made in purlin spacing or sheeting sizes.
Splices in portal and other frames shall be made where shown on the details or where directed by the Engineer.
BOXED MEMBERS
Abutting edges of boxed members shall be connected and sealed with a continuous weld to exclude the entrance of moisture. Where specified such welds shall be ground flush to approval.
SHOP ASSEMBLY
Assembly of units in the shop prior to transportation to the site must be inspected by the Engineer before painting. The assembled work shall be laid out in the shop or yard such that all parts are accessible for inspection and testing.
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The Sub-Contractor shall furnish all facilities for inspection and testing of the works and he must notify the Engineer on every occasion materials are ready for inspection.
MARKING
All members of the structure to be site-assembled shall be marked in accordance with the shop details marking plans submitted to the Engineer for approval.
ERECTION
SITE DIMENSIONS
Erection shall not commence unless and until accurate site dimensions have been taken by the Sub-Contractor. No claims will be considered should site dimensions differ from those on the Drawings. Any modifications to the structural steel required in order to comply with site dimensions shall be made on the ground to the Engineer's approval before erection commenced.
SAFETY
All erection shall be carried out by competent and experienced personnel and the Sub-Contractor shall take every care to safeguard members of the public, workmen, and adjoining property against injury and/or damage. The Sub-Contractor shall be held responsible for all damage caused to the structure, workmen, or other property during erection.
All gear used shall be of adequate strength and shall comply with all current Regulations.
During erection the work shall at all times be adequately bolted, guyed and/or braced to make the structure secure.
STORAGE AND HANDLING
Steel members shall be stored, handled and erected in such a manner
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that no member shall be subjected to excessive stresses which could have an adverse effect on the properties of the steel. If, in the opinion of the Engineer, the steelwork has been subjected to such treatment, the Sub-Contractor shall remove the member from the site and replace it at his own expense.
ERECTION NOTES
No member or part of a member which has been bent or distorted shall be erected in that condition. All straightening shall be done on the ground.
Stanchions shall be wedged to line and level on steel or cast from wedges and checked by the Engineer. After acceptance, stanchion bases shall be grouted to approval before wedges are removed. Unless otherwise shown on the Drawings, all stanchions shall be left truly vertical and correct to line and level. Beams, girders, etc., shall be erected level unless otherwise shown, and correctly positioned.
Trusses and open web joints shall be carefully handled at all times and during erection shall be lifted at such points and in such a manner as will preclude any possibility of damage from excessive stresses.
Packing plates, shims, washers or similar adjusting pieces found necessary to accommodate tolerance in structural site dimensions shall be provided and fixed to the approval of the Engineer.
Immediately after erection, each truss shall be made secure by purlins, bracing or guys to approval of the Engineer.
Bracing shall be fixed in position as soon as dependent portion of the work is completed.
TIGHTENING AND TESTING HIGH TENSILE FRICTION GRIP
BOLTS
Before assembly, the contact surface, including those adjacent to the washers, shall be descaled, and be free from dirt, oil, loose scale,
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burrs, paint (except priming paint), pits and other defects that would prevent proper seating of the parts.
Bolts shall be fixed with approved hardened flat or tapered washers as required between the bolthead and nut and the softer mild steel.
When bearing faces of the bolted parts have a slope of more than 1 in 20 with respect to a plane normal to the bolt axis, square smooth bevelled washers shall be used to compensate for lack of parallelism.
All bolts shall be tightened by the "Turn of Nut" method. This method shall generally be as specified in B.S. 3249 and as approved by the Engineer to achieve in all bolts a minimum tension equal to the proof load.
GROUTING
Unless otherwise detailed on the Drawings, a space of not less than 40 mm shall be provided undersides of column baseplates and footings, and between all beams and roof truss bearings and concrete pads.
After each column, beam or roof truss has been wedged up to a line and level and fixed in position to approval, the space between footing and pad and the underside of the one base-plate or steel member shall be grouted by the Main Contractor with 1:1 Cement: Sand mortar.
The Portland cement and sand shall be thoroughly mixed together with sufficient water to produce a mixture or "damp earth" consistency and shall be used within twenty minutes of mixing.
The caulking mixtures shall be packed tight into the space between baseplate and foundation and protected from damage until it sets.
PAINTING PAINTS
All paints are to be obtained from a Supplier approved in writing by the
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Engineer.
Paints are to be delivered to the Site or to the Contractor's fabrication site in the original containers as supplied by the manufacturer, with seals unbroken, and are to be used in strict accordance with the manufacturer's instructions.
Manufacturer's representatives are to be free to visit the Site and inspect materials for laboratory analysis. Paints are not to be thinned unless instructed by the Engineer. No external painting is to be carried out during rain or when rain is likely to occur before the paint has had time to dry. All surfaces are to be dry and free from moisture during painting.
PREPARATION FOR PAINTING
All structural steel shall be thoroughly scraped and wire-brushed to remove mill scale and rust. Dirt, grease and oil shall be washed off with white spirit and the steel allowed to dry.
APPLICATION
A first coat of an approved primer shall be applied after fabrication of the works has been completed. A minimum of 24 hours shall elapse before the steel is moved from its position after painting.
After delivery to Site, the steel shall be carefully examined and all areas where the priming coat has been damaged and/or where rust has developed shall be washed white spirit and wire brushed as necessary and a further priming coat as for the first coat applied to completely cover the damaged areas.
During erection, surface of steel which are to be in contact shall be painted with one further coat of primer as previously described and the surfaced brought together whilst the paint is still wet.
After erection, a second coat of an approved primer and a third coat of micaceous iron oxide shall be applied. Welds shall not be painted over until they have been deslagged, inspected and approved.
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Steel purlins and side rails shall generally be painted as for steelwork except for purling and rails supporting aluminium sheeting, when the following specification shall be used:
Prime Coat-Red oxide sonc chromate primer, or red lead graphite, or other approved primer.
Finishing Coat -As specified by the Architect/Engineer
The interior of mild steel gutters shall be prepared as previously described and painted with 2 coats of Robbialac Epilac Coal Tar Epoxy Paint, or other approved paint.
PRICES MEASUREMENT AND PAYMENT
Prices quoted by the Sub-Contractor shall be based on the calculated weights of steel, and shall include for shop drawings, manufacture, painting, and supply, all as specified and as shown on the Drawings, including the cost of delivery to the Site or other agreed place or places and the supply of bolts, rivets, plugs, gussets, cleats, to complete the erection of the works.
Prices shall include for erection, (all labour, scaffolding and other erection equipment necessary) and cover the cost of additional prime coat painting as previously specified. The prices shall also include for lining up, levelling and plumbing, and grouting up of the bases.
The basis for payment for steelwork shall be calculated steel weights of the structure. Any variation in design which result in either a net increase or decrease in steel weight from the quoted amount in excess of 25% shall result in the appropriate additions or deductions to the agreed quotation.
Any written instructions from the Engineer which may result in additional work over and above that for which the Contractor quoted will be considered as extras and shall be paid for in the basis of calculated additional steel weights.
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RAINWATER GOODS
GENERAL
Rainwater goods shall be in accordance with particular Specification and as shown on the Drawings and as per the direction of the Engineer. Rainwater gutter and pipes shall be made out of steel sheets of the required thickness.
PVC RAINWATER PIPES
The Contractor shall supply and fix heavy-duty grey PVC pipe and fittings as indicated on the drawings and schedules.
Pipes and fittings shall be in accordance with relevant B.S. including B.S. 4514 and fixed to the manufacturer’s instructions and B.S. 5572.
The rain water pipes system shall incorporate synthetic rubber gaskets as provided by the manufacturers whose fixing instructions shall be strictly adhered to.
Suitable supporting brackets and pipe clips shall be provided at maximum of one metre centres.
The Contractor shall be responsible for the joint into the Gully Trap/Rain water grits on Drain as indicated on the drawings.
PIPE SUPPORTS
This Sub-Clause deals with pipe supports securing pipes to the structure of buildings for above ground application.
The variety and type of supports shall be kept to a minimum and their design shall as such as to facilitate quick and secure fixing to metal, concrete, masonry or wood.
Consideration shall be given when designing supports, to the maintenance of desired pipe falls and the restraining or pipe movement to a longitudinal axial direction only.
The Contractor shall supply and install all steelwork forming part of the pipe support assemblies and shall be responsible for making good any damage to builders work associated with the pipe support installation.
The Contractor shall submit all his proposals for pipe supports to the Engineer for approval before any erection work commences.
The Contractor shall allow for priming and painting of the exposed rain water down pipes to approval.
FIXING
Sheeting and rainwater goods shall have fixings generally in accordance with B.S. 1494. Rainwater gutter, pipes, etc., shall be fixed properly with necessary accessories to avoid any leakage of rainwater.
Asbestos-cement sheeting shall be fixed in accordance with the manufacturer’s instructions, to leave a perfectly water-tight roof.
INTRODUCTION
Profiled steel sheeting shall be used in these buildings if approved non- corrosive ad guaranteed coating has been applied on internal surfaces of the sheeting.
RIDGE OF THE ROOF
The ridge capping is constituted of purpose-made fibre-cement sheets. These sheets are placed with the same transversal overlapping as the roof sheets and with the corresponding vertical spacing as well.
PIPE PENETRATIONS
The penetrations of the roof by pipes are carried out by means of :
Flashings sheets
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Box housing
Covered by a cowl corresponding to the diameter and the number of pipes.
The flashing sheets and the box housing are to be placed on bearer battens, and shall have the same transversal and lateral overlapping as the folded sheets and shall be fixed in the same way.
Water tightness between the cowl and the pipes is to be achieved by packing with tarred yarn and filling up with sealant mastic.
PURLINS SUPPORTING THE ASBESTOS SHEETS
The purlins shall be made of steel profiles.
It is compulsory that the purlins be stabilized by anti-sag bars for spans over 3m.
Both the purlins and the attachment of these and their supports shall be calculated in the compliance with the British Standards and the loads defined earlier.
SHEETING WITH PROFILED STEEL SHEETS
Sheeting consisting of profiled steel sheets pre-painted on the outer side shall be resistant to the climate and shall be coated with corrosion resistant material.
The sheets shall be galvanized or factory-preprinted on both sides with a zinc covering of 400 g/s.m. or corrosive resistant material respectively on each side, in accordance with the British Standard or DIN concerning galvanized steel plates/sheets.
The design of the profiled steel sheets and the fastening of the profiled steel sheets for cladding and roof shall be to British Standards and the loads as described before.
Screws shall be supplied with coloured head and shall be according to the supplier’s specifications.
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Wherever possible standard solutions shall be carried out.
Where two different elements of the construction are joined, notably the details between roofs and the machine tower, there shall be windproof and water-tight overlapping.
INTERLOCKING CONCRETE TILES
Interlocking concrete roof tiles and ridges shall have integral colouring and shall be obtained from an approved source and otherwise to approved samples and colours, and shall be laid strictly in accordance with the manufacturer’s printed instructions.
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WALLING
STANDARDS
A. The requirements of the following British Standards and Codes of Practice shall be observed:-
BRITISH STANDARD B.Bricks and blocks of fired brickworkclay or shaleB.S. 3921 Part 2
C. Concrete bricks and fixing bricks B.S. 1180
D.Shapes and dimensions of special bricks B.S. 4729
E.Precast concrete blocks (for general use and load bearing B.S. 2028 walls above damp proof course) B.S.1364 Type B
F.Precast concrete blocks (for internal B.S.2028 non-load bearing walls) B.S.1364 Type C
G.Sand for mortar for plain and B.S. 1200 Table 1 reinforced brickwork, block walling and masonry and Table 2
H.Building lines (Hydrated line) B.S. 890 Part 2
J.Ready mixed lime: sand for mortar B.S. 4771
K.Mortar plastioizers B.S. 4887
L.Methods of testing mortars and Specification for mortar testing sand B.S. 4551
M.Materials for damp proof courses B.S. 743
N. Milled sheet lead and strip for building purposes B.S. 1178
O.Metal ties for cavity wall construction (vertical twist type)B.S. 1243 Fig. 1
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CODES OF PRACTICE P.Structural recommendations for load bearing walls C.P. 111 Q.Walling C.P. 121 Part 1
R.Masonry - rubble walls C.P.121, 202 Part 1
S.Walls and partitions of blocks and slabs C.P. 122
T.NOTE : The Contractor's attention is drawn to Section `G' of the Standard Method of measurement. U.WATER shall be as specified in "Concrete work".
V.CEMENT shall be as specified in "Concrete work".
SAND shall be as specified in “Concrete work”.
Lime shall be hydrates limes for cement/lime mortars and comply with B.S. 890, semi-hydraulic class “B” calcium limes.
Concrete Blocks shall be solid or hollow blocks to comply with the relevant standard as previously mentioned and shall be solid hard, true to size and shape and sharp arrises and in accordance with Ministry of Works, Standard Specification for Metric sized concrete blocks for walling dated September, 1972.
All concrete block walling indicated as load bearing shall have a minimum average crushing strength of 3.5 or 7.0 newtons per square millimetre or as otherwise specified in Particular Specification.
They shall be obtained from an approved manufacturer or manufactured on site in approved block making machines. The mix used shall not be less than (1:9) by volume and maximum size of aggregate shall be 12 mm size. The blocks on removal from the machine shall be laid on edge or racks under sheds erected by the Contractor and left for 3 days during which period they shall be kept constantly wet.
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After this initial period they shall be placed on edge in the open racks and protected by sacking or other approved covering and kept wet for a further 5 days.
Thereafter the blocks shall be left in the same position without wetting for a further 20 days. No blocks shall be used in the Works until 28 days old and until samples have been tested and approved by the Engineer.
The Contractor shall ensure that the blocks are stocked separately in their respective categories in the structure in the position shown on the Drawings.
Stone for Walling shall be good hard local stone equal in Standard and quality to “Nairobi Blue Stone”. Stone shall be squared, butchered or smooth dressed and joints chisel dressed on the face. Masonry work to receive render shall be so dressed as to reduce dubbing-out to a minimum.
The coursed stone shall not be less than 150 mm deep and 305 mm long. All stone shall be laid on its natural or quarry bed lines.
Gauged mortar shall be used for walling and shall be composed of the part Portland Cement to two parts hydrated lime and nine parts sand (1:2:9) measured in gauge boxes thoroughly mixed dry preferably with an approved mixing platform with water added afterwards until all parts are completely incorporated and brought to a proper consistency and used within the hour.
No partially or wholly set mortar will be allowed to be re-used or re-mixed.
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All stone shall be wetted before laying and the top of walling where left off, shall be wetted before re-commencing building, walls to be kept wet 3 days after building.
All blocks and walling to be kept true, plumb and level with all perpends vertical and in lime and work shall not rise more than three courses above the adjoining work and all such rising are to be properly racked back.
The Contractor must provide proper setting out or storey rods so that all work is coursed to cills, lintels and underside of beams thus reducing horizontal cutting to a minimum.
All walling must be carefully bounded together so that no vertical joint in any one course is nearer than 100 mm from the joint in the course above or below.
All walling must be bedded in solid mortar with cross joints will flushed up at each course as the work proceeds.
J. To walls less than 190 mm thick the reinforcement shall consist of gauge 24 “Expament” wall reinforcement horizontally in bed joints every alternate course and lapped over “expament” from column where abutting same.
K. Rates for walling are to include for reinforcement strips.
LABOURS ON STONE WALLING
Labours stated in the Standard Method of Measurement as to be included shall be deemed to include for redressing the beds of stones on site to the minimum extent necessary to obtain uniformity of coursing and for any redressing of faces necessary to bring the
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thickness within the tolerance specified. Where described as fair face, the stones shall be of approved colours and chisel or machine dressed to provide the required finish to the Architect’s approval. They shall be built to equal or varying courses with neat, flush or recessed joints to an approved sample.
Rates for walling of any description are to include for all expenses in connection with the provision and conveyance of samples of walling materials to the Ministry of Works or other approved Materials Testing Laboratory.
EXPANSION JOINTS
Filler materials shall be Flexcell as manufactured by Expandite Ltd., or equal and approved. Sealers shall be plastic or sealastic or equal and approved applied in accordance with the Manufacturer’s instructions.
BRICK FACEWORK
Brick facework shall be to the thickness shown on the Drawings or otherwise specified. The bricks shall be obtained from Kenya Clay Ltd. or such other source(s) approved by the Architect and they shall be hard and true to shape, including overburns (if so required) to give a variation in colour. They shall be laid on a mortar bed with straight horizontal joints and true perpends and shall be firmly anchored to the walls using wall ties. The ties must be galvanised metal of suitable strength and girth, twisted to a figure ‘8’ and built into walling and facing; the walling and facing being set to leave a reasonable gap (say 5 mm) to minimise afflourescence. Colour washing will not be permitted unless approved by the Architect.
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ASPHALT WORK
A.The requirements of the following British Standards shall be observed:- BRITISH STANDARD
B.Mastic asphalt for tanking and damp proof B.S. 1162, 1410 courses (Natural rock asphalt aggregate) and 1418
C.Mastic asphalt for tanking and damp proof B.S. 988, 1097 courses (Limestone aggregate)1076 and 1415
CODES OF PRACTICE
D.Protection of buildings against water from ground C.P. 101
E. NOTE: The Contractor’s attention is drawn to Section “J” of the Standard Method of Measurement.
F. All asphalt shall comply with the requirements of subsections B.S. 1418 and 1097 and
P.C. 102 specifically dealing with tanking operations.
G. For tanking to basement lay over the whole area of the basement concrete floor horizontal damp proof course in three thickness laid with 150 mm laps to a total thickness of 30 mm and carried through walls and to outer edge of top course of foundations outer face of wall to cement with vertical damp proof course with a double angle fillet.
H. Vertical face of basement walls shall then be covered with damp proof course applied in three thickness with 75 mm laps total thickness of not less than 20 mm.
J. Vertical damp proof course shall be carried up to covered height of 150 mm above ground level and connected at bottom to horizontal damp proof course in walls with double fillet formed on top of foundations to form a complete tank to basement.
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K. All junctions between horizontal and vertical asphalt shall be warmed, cleaned and properly made good with two-coat angle fillets at all integral angles.
L. Properly made good joints between lining pits and horizontal damp proof course to floor shall be effected and double angle fillets to all internal angles maintained.
A. It is essential that continuity of tanking be maintained. Care must be exercised to see that such continuity is not destroyed by stanchions, pits, sumps etc.
A. Protect asphalt by the application of loading coats immediately each section of Work is completed. Pumping of any water gaining access shall be continued until not only the asphalt work is complete, but also until loading coasts are thoroughly set.
A. If the water level is near such water level shall be maintained at not less than 0.3m below the level of the base concrete during the progress of tanking work to avoid the application of asphalt on wet surfaces and this pumping operation shall be maintained until the temporary sump has filled and sealed.
A. Roofing Asphalt
Roofing asphalt shall be mastic asphalt to B.S. 988/1988, Table 3 column 111 and shall be laid by a specialist sub-contractor to be approved by the Architect and to the requirements of C.P. 144.
The asphalt shall be laid in two coats to a thickness not less than 20 mm on a black sheathing felt to B.S. 747 : Part 2 Type 4A (I) weighing not less than 17 Kg. Per 25 m roll and shall be finished with
aluminium bituminous paint to the Architect’s approval. The contractor’s rates shall include for complying with all these
A.
requirements.
Roofing Tiles
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Roofing tiles shall be a shown on the drawings and/or measured in the Bills of Quantities and shall be form a source approved by the Architect.
The tiles shall be laid strictly in accordance with the manufacturer’s instructions so as to keep the roof truly watertight.
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ROOFING: BITUMINOUS FELT ROOFING
GENERAL
All work shall be executed by a firm approved by the Architect in writing.
The Sub-Contractor shall obtain from the Contractor a statement in writing to the effect that the screed is dry, clean and satisfactory before the coverings of fest are laid. A copy of the statement is to be forwarded to the Architect.
The Contractor shall obtain form the approved Sub-Contractor for felt roofing work a written guarantee and undertaking that a period of a twelve calendar month from and after the certified date of completion of the whole of the works such Sub-Contractor shall at his own expenses make good to the satisfaction of the Architect all and any defects in the felt roofing work which shall be attributable to improper materials or faulty workmanship and shall bear the cost of any consequential damage to the structure.
WORKMANSHIP
All surfaces to receive felt are to be cleaned before and as the work proceeds.
All work shall be laid to falls without hollows or loose patches.
BITUMEN FELT ROOFING
Built up roofing felt shall be “Cabro” coloured fibre-based mineral surfaced felt complying with B.S. 747, part 2, supplied by Messrs Cassman Brown & Company Ltd., P.O. Box 18072, Nairobi. The bottom layer shall be type 2C self-finished as asbestos weighing not less than 13 Kg. Per 10 S.M., the intermediate layer type 1C self finished bitumen felt of similar weight and the top layer type 1E mineral surfaced felt weighing not less than 36 Kg. Per S.M.
The primer shall be “Cut back” bitumen solution of suitable viscosity
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and the bonding compound shall be oxidised or “blown” bitumen melted and applied hot. Nails shall be galvanised, extra large head, felt nails complying with B.S. 1202 Type IV G.
All roof work shall be laid with a number of layers of felt as described, to a maximum thickness of 3/8” (10 mm) lapped across falls with minimum laps of 2” (50 mm) at edges and 3” (75 mm) at end of sheets, full hot bonded either by pouring and rolling or mopping with bitumen bonding compound laid an even thickness using 13 Kg. Bitumen per square metre of roofing substructure and between layers, with successive layers of felt laid breaking joint.
Cement surface shall be primed before receiving bonding compound. All adjoining work shall be protected from damage due to laying and all stains shall be removed and made good.
QUARRY TILING
Quarry tiles shall be size 200 x 200 x 22 mm thick and shall be obtained from an approved manufacturer. They shall be laid square on one layer or roofing felt or as specified and be jointed in cement mortar (1:4), the joints being kept as fine as possible.
CHIPPINGS
Mineral aggregate chippings shall be approved hard, angular light coloured stone chippings to pass a 10 mm sieve and be retained on a 6 mm sieve. These shall be laid as soon the roof is clear of other trades. They shall be closely bedded at a rate of 16 Kg/S.M. on a hot bitumen dressing compound, and all loose chippings removed.
PROTECTION
The roof shall be protected against damage by following trades and in no circumstances shall the roofing be used as a building platform, for storage of materials, for mixing concrete and/or heating materials. All roofing and adjacent work shall be left clean.
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FLAT ROOF WATER PROOFING WITH EPDM RUBBER
SPECIFICATION OF WATERPROOFING MATERIAL
The water proofing materials shall consist of a single ply HERTALAN EPDM RUBBER, shall not be less than 1.2mm thick and shall have the properties specified below (unless otherwise agreed at the time of award of the contract).
The membrane material shall be supplied by the manufacturers in sheets (or rolls) large enough to minimize jointing which shall be capable of forming single bends in situ. At the points where the membrane goes over parapet, proper care shall be taken to seal the edges per manufacturer’s specifications, including chiselling grooves to tuck in the rubber.
Before fixing the waterproofing membrane, the substrate must be smooth, clean, dry, and free of oil/fat, sharp edges and foreign materials. All bituminous waterproofing materials previously used must be removed in total and carted away. The membrane shall be adhered to the substrate at least 50% using an adhesive specified by the manufacturer.
The rubber surfaces shall be painted with two coats of rubberized pain as manufactured by Crown Paints, to give a grey finish or any other colour that may be specified. Areas as specified in the drawings, prone to mechanical damage shall be protected by installing paving tiles.
The application of waterproofing membrane shall be carried out by a specialist sub-contractor who is to be specifically approved by the architect and will be required to give a TEN YEARS GUARANTEE against workmanship backed by a similar guarantee for materials from the MANUFACTURERS. Such a SUB-CONTRACTOR will have had a demonstrable experience in installing such materials in East Africa.
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Property Test or Requirement Demonstration
a) Thickness/uniformityBS903 Part A38In the range of +3% to 5% stated thickness.
b) Tensile strength andBS 2782 Method Minimum Tensile Strength at Elongation210Abreak 4kN/m Minimum elongation at break 350%
c) Tear Strength BS 903 Part A3Minimum tear strength 8N/mm
d) Thermal expansionChange of dimension at 100 degrees centigrade Maximum +1%
e) Resistance to aging andDIN 7864 Heat agingTensile strength maximum Weathering at 80 degrees change on (b) above after 28
days 20% Elongation at break, maximum change on (b) above after 28 days 20%.
f) Deterioration by limeDIN 7864 Tensile strength, maximum Change on (b) above after 28 days 20% Elongation at Break.
g) Ozone resistanceBS 903 Part A4No visible cracking under 7 x Magnification after being exposed under strain to the standard ozone
rich atmosphere
h) Robustness Contractor to The material must be sufficiently provide evidence forrobust to be suitable for similar workinstallation on the basis foreseen in the contract.
i) Bio-degrationContractor to providethe material shall be immune evidence for similar workto bacterial attack for installed conditions at the
site.
j) Chemical ResistanceContractor to provide Good resistance to corroding features of supply materialsubstances with which the material may come in contact in installed conditions at the site.
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VANDEX PRODUCTS
SPECIFICATION FOR WATERPROOFING CONCRETE STRUCTURES
Remedial Work:
All areas shall be examined for structural defects.
Shrinkage cracks exceeding 0.3mm (0.01”) in width shall be cut or chiselled out at least 10mm wide and 15mm deep and washed out. Then a slurry coat of Vandex Super shall be applied. Following this the groove is filled with a mixture of 3 to 1 sand and cement in stiff mortar consistency.
Over-poured forms, around columns and/or inverted beams, form groves shall be cleaned out, rinsed with water and slurry coated with Vandex Super. These grooves shall then be filled flush with a mixture of 3 to 1 sand and cement.
Any honeycombed concrete found in walls and/or inverted beams/columns shall be raked out to solid concrete, washed out with water, coated with a slurry coat of Vandex Super and filled out flush with a 3 to1 mixture of sand and cement.
Cleaning
Concrete surfaces must be free from all form scale, laitance, algae growth, mould, oil, curing agents and any other foreign materials. The finish of the surfaces shall be a brush finish.
All laitance (cement scum) shall be removed as soon after pouring as possible.
Pre watering
Concrete shall be thoroughly wetted down in order to achieve the penetration of the activated chemicals and thereby starting the crystalline growth throughout the capillary tracts. All free lying water must be removed from
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surface, leaving the concrete in a damp condition just prior to Vandex application.
Mixing
Vandex Super is mixed to slurry consistency. Add approximately 0.8 parts water to 2.00 parts powder or 9 liters to 25 Kg when mixing full bags, and mix thoroughly until the mixture is free from lumps.
Application
The pre-watered concrete surface shall receive two coats of Vandex Super coat approximately 0.75 Kg/sq.m. Use a Vandex brush and work the material well into the surfaces.
The application should be as even as possible trying to avoid thick and thin spots. Areas applied too thick will not cure right and when drying cracks and subsequently peeling may form.
The second coat may be applied when the first coat has set and is not drawn off by the second coat.
Curing and protection
Vandex applications must be protected against sun and rain. After the application is dry to the touch, cover with polyethylene sheet (hessian cloth) or wet sand for five days. If this is not possible, sprinkle with water several times a day for five days. Do not apply Vandex materials at temperature below 5 degrees C or on supercoiled structures.
Additional Information
When concrete is poured in sections, it is recommended that each section is keyed. After keyed form is removed and just prior to pouring the next section the construction joint shall receive a slurry coat of Vandex Super (1.5 Kg/sq.m).
This does not apply to control or expansion joints.
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CARPENTRY, JOINERY AND IRONMONGERY
GENERALLY
All timber for permanent work in the buildings shall, before use, be approved by the Architect for quality in accordance with the foregoing specification for its respective grade.
All Carpenter's work shall be left with sawn surface unless particularly specified to be wrot. Scantlings and boarding shall be accurately sawn and shall be uniform in width and thickness throughout. All Carpenter's work shall be accurately set out and in strict accordance with the Drawings and shall be framed together and securely fixed in the best possible manner with properly made joints. Provide all brads, nails, screws, bolts, etc., as necessary. Nails shall comply with BS 1202 and bolts with BS 916.
Variations from specified dimensions of scantlings shall not exceed the tolerance stated in the aforementioned Grading Rules. Board 1" thick or less shall hold up to the specified sizes. All timber shall be as long as possible and practicable to eliminate joints.
Sizes and thickness of wrot carpentry and joinery are nominal that is to say 3 mm reduction off specified sizes will be allowed for each wrot face, except where described as finished sized in which case no reduction from the stated thickness or size will be permitted.
Ends of timbers required to be built into walls shall have 12 mm air space between same and walling.
All joiner's work shall be wrot unless otherwise described.
All mouldings shall be accurately run and finished and all arrises shall be slightly rounded. Framed work shall be cut out, properly tenoned, shouldering, etc., and framed together as soon after the commencement of the Works as is practicable but should not be wedged up until required for fixing in position and any portions that warp, get in winding, develop shakes or other defects shall be replaced
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with new.
As soon as required for fixing in position the framing shall be glued together with best quality glue and properly wedged or pinned etc., as described.
Unless otherwise described oval or round brads will be used for fixing all face work, all heads shall be properly punched in. Where described as pelleted work screws shall be countersunk and the screw heads covered with timber pellets to match the adjacent timber.
All plugs employed as fixings for joinery, etc., unless otherwise stated shall be "philplug" or other equal and approved, filled into holes of a suitable size. The holes shall be drilled with special masonry drills and not cut with a cold chisel and hammer. Under no circumstances will wooden plugs be permitted. The expression "plugged" shall be taken to mean fixed with and including plugs as last described to stone or concrete. Timber to be left for polishing shall be specially selected and approved and have adjacent places matched and uniform or symmetrical in colour and grain. All fixed joinery which is liable to become bruised or damaged in any way shall be properly cased and protected by the Contractor until the completion of the Works.
Should any of the Carpenter's or Joiner's work shrink, warp, wind or develop any other defects within six months after the completion of the Works, the same shall be removed and new fixed in its place together with all other work which may be affected thereby, all at the Contractor's cost and expense.
QUALITY OF TIMBER
The qualities of timber stated herein are those named and described in "The Export of Timber Rules, 1964".
All timber described as "Sawn Cypress" shall be Grade II (select grade) sawn cypress.
All timber described as "wrot cypress" is to be approved Grade I (Prime
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Grade) wrot cypress.
All timber described as "wrot cedar" is to be Grade I (Prime Grade) wrot cedar.
All timber described as "wrot hardwood" shall be First Grade Hardwood.
No joinery work is to be put in hand until the Architect has seen and approved the colour and grain of the timber to be employed.
All the above timbers when used for Carpenter's work are to be well seasoned to a moisture content not exceeding 20% of their dry weight. When used for Joiner's work they are to be kiln seasoned or air dried and when delivered to site shall have a moisture content not exceeding 15% of their dry weight.
All timber for permanent work in the building shall before use, be approved by the Architect for quality in accordance with the foregoing specification for its respective grade. Any timber not so approved is to be removed from the Site immediately. Where practicable, timbers shall be in one length to eliminate joints.
All timber is to be clearly marked to denote grade.
PRESERVATIVE TREATMENT
All Structural timber employed in Carpentry Work or where otherwise specified is to be celcurized to a retention of 0.4 lbs. of dry salt per cubic foot of timber. Any cut ends are to be painted with the appropriate solution to leave no untreated surfaces.
Timber so treated must have been reduced to the required moisture content before being incorporated in the works.
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PRIMING WOODWORK
All woodwork which is to be painted or hidden from view and the bottoms and tops of all doors and the backs of all frames are to be primed before fixing. Priming shall be touched up from time to time during the progress of the work.
SITE DIMENSIONS
Before putting in hand any joinery work, whether to be built in with the carcass or fixed later the Joiner is to ascertain and check all dimensions on the Site which affect or govern Joinery Work.
SCRIBING
All mouldings, frames and any other Joinery work shall be accurately scribed to fit the contour of any irregular surface against which they abut either at ends or longitudinally.
PLYWOOD
The plywood shall generally conform to the requirements of BS 1455 and shall be Grade 2 Bonding INT. Where described as external quality it shall be Grade 2 Bonding M.R.
BLOCKBOARD
Where blockboard is specified, it is to be in accordance with BS 3444, of the thickness specified and absolutely solid and glued throughout.
VENEERS
All veneers to be specially selected for grain and colouring and no veneered work shall be put in hand until the Architect has approved grain and colour.
HARDWOOD
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Hardwood shall be as specified on the Drawings or otherwise measured or other equal and approved suitable for painting in accordance with BS 1142 and shall be prepared and fixed strictly in accordance with the manufacturer's instructions.
LAMINATED PLASTIC SHEETS
Laminated plastic sheets are to be as specified on the Drawing or otherwise measured in the Bills, or other equal and approved, of a colour to be selected by the Architect.
FLUSH DOORS
Flush doors in general are to be of the thickness stated complying with BS 459 Part 2A; hollow, semi-solid or solid cored, interior or exterior quality as required and veneered as described. All flush doors shall be faced with 4 mm plywood or 3 mm MDF, as specified, both sides on ex 25 mm horizontal internal construction at 50 mm centres with 2 No. 10 mm round vent holes throughout top to bottom and in addition are to have 10mm hardwood lipping all round morticed and glued into framing. Styles, top and bottom rails to be ex 50 x 75mm with an additional ex 50 x 75 mm intermediate rail 150 mm below top of the door and 225mm above the bottom of the door. Lock blocks are to be on both sides of door and to be 150 x 300 mm. Samples of flush doors are to be submitted to the Architect for his approval before bulk orders are placed.
OTHER DOORS
All doors (except flush doors) are to have tenoned ends covered by a cover strip of matching timber with grain running with and matching that of the door and is to be glued sunk screwed and pelleted in position.
IRONMONGERY
The Contractor is to order and to check consignments of Ironmongery upon receipt and store them in safe keeping until required for fixing.
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All ironmongery shall be fitted and fixed in the best possible manner. Rates for fixing are to include for all cutting, sinking, boring, mortising and fitting in hardwood or softwood and for supplying all necessary and matching screws. Rates for door furniture shall also include for fixing before painting, removal during painting operations and afterwards refixing and for labelling all keys with door references and handing to the Architect upon completion. Two keys will be provided for each lock and the Contractor is to allow in his rates for a master key system to all Departments except the Staff Houses, including supplying master keys.
All locks, springs, and other items of ironmongery with movable parts shall be properly tested, cleaned, properly lubricated with graphite and adjusted where necessary and left in perfect working order upon completion of the works by the Contractor who shall include for this in his prices for fixing.
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METAL WORK
GENERAL
All materials shall be the best of their respective kinds and all work carried out as directed by the Architect.
Mild steel shall be of approved manufacture complying with the requirements of BS 15. Screws, bolts, washers, etc. to comply with BS 1916 and 1494.
Welds to be neatly executed, filled smooth and left clean. Aluminium sections shall comply with the requirements of BS 1161, with surface finishes to the Architect's approval.
Metal windows and doors shall be supplied by a sub-contractor, approved by the Engineer after documentations have been submitted.
Considerable care shall be taken in the transportation, handling and storing of the metal windows and doors and in their protection from damage after they are fixed in position.
The windows and doors shall be pointed all round with Evomastic Dutyl 37 or other equal and approved caulking mastic applied with an approved caulking gun. A temporary hardboard slip shall be fixed all round both sides of the windows prior to plastering or rendering in order to provide a gap for this pointing.
PARTITIONS, GENERALLY
Lightweight or demountable partitions shall be as shown on the Drawings and/or measured in these Bills of Quantities.
Aluminium Partitions
Aluminium framework, where specified, shall be anodised or powder coated to approved samples and shall comply with the relevant BS Standards.
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Drywall Partitions
Where specified, partitions shall be Drywall Pelican Systems comprising drywall studs and gypsum boards. The studs shall be cut to lengths and spaced as specified by the manufacturer or in accordance with the Architects’ Drawings. They shall be jointed together with stud connectors to produce a rigid system and shall be covered with gypsum boards and/or glazed as shown on the Drawings or otherwise directed. Joints in the gypsum boards shall be covered with paper tape and flushed over with jointing compound, ready for decoration as specified elsewhere in these Preambles.
Rates for drywall studs shall include for cutting to required lengths, stud connectors, rigid angles, edges and the like, drilling, screws and waste. Rates for boards shall similarly include cutting to size, drilling, fixing and waste.
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FLOOR, WALL AND CEILING FINISHING
GENERAL
The whole of the plasterwork and other wall, floor and ceiling finishings shall be executed to the entire satisfaction of the Architect and any work rejected shall be taken down and re-executed by the Contractor at his own expense. All scaffolding, temporary rules and screeds, tools or special appliances required shall be furnished by the Contractor.
CEMENT
Shall comply with the requirements of BS 12.
LIME
The lime shall comply with BS 890. Class A, non-hydraulic, and shall be run to a putty in a pit dug on site or in an approved container. Water is first to be run in and the lime added until it is completely submerged. It shall be kept submerged and stirred vigorously until all lumps are disintegrated. The resulting lime putty shall then be run through a fine sieve and placed in another container and kept clean and moist for not less than eight weeks before use.
SAND
Sand shall comply with the requirements of BS 1199 graded in conformity with Table 1 hereof.
“BELZONA” CLEAR CLADDING
“Belzona” Clear Cladding (Local agents: Molecular Maintenance Ltd., P.O. Box 18208, Nairobi) shall be used strictly in accordance with the Manufacturer’s printed instructions and in the areas specified by the Architect.
“BOMANITE” PAVING
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“Bomanite” Paving is a proprietary finish available from and done by “Bomanite“ (Kenya) Ltd., P.O. Box 41103, Nairobi and from whom further information may be obtained. Where specified or otherwise directed, this material shall be used strictly in accordance with the manufacturer’s printed instructions.
“ECLIPSE” FLOOR FINISH
Where specified, “Eclipse” floor finish shall be used strictly in accordance with the manufacturer’s printed instructions. This product is obtainable from Thika Works Ltd., of P.O. Box 30185, Nairobi
PAVINGS GENERALLY
Surfaces to be paved shall be wire-brushed, well wetted and pointed with a cement and sand (1:1) grout before any paving is applied.
All pavings shall be laid with joints coinciding with the construction joints in concrete beds on which they are laid and the pattern set out accordingly and they shall be kept continually damp for seven days before application during which period no traffic will be permitted over them.
POLISHED COLOURED CEMENT AND SAND PAVING
Cement and sand shall be composed of one part cement to one part sand to three parts of 1/4" to 1/8" gauge black trap grit, applied in one operation to the thickness shown on the drawings. The contractor shall allow for lightly polishing the finished surface perfectly smooth and hard with a steel trowel and dead level or to true falls if so described. It is most important that the polishing is not overdone, that neither water nor dry cement is added during this operation and that no trowel marks nor rough areas are left.
Cement and sand pavings shall be coloured by the admixture of "Cementone" or other equal and approved colouring pigment for the full thickness of the paving and skirtings. A sample of the required tint shall be approved by the Architect before work commences and all
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pavings shall thereafter comply in every respect with the approved sample.
Finishes shall be machine polished to a fine even surface free from voids or pits. Surfaces shall first be washed clean and rough polished and all holes, etc., filled in with an approved filler and left for a 24-hour period. Finally the work shall be washed down and given a final polish to the texture approved by the Architect.
POLISHED GRANOLITHIC OR TERRAZZO PAVING
Granolithic paving shall be composed of one part of cement to two parts of approved colour stone chippings (Nairobi black trap or other approved) graded from 6 mm downwards and with a maximum of 10% of stone dust laid to the thickness required in bays separated by approved black plastic strips.
No bay shall exceed 7 square meters and the pattern is to be approved by the Architect before work commences. The paving is to well rolled and left to cure thoroughly before polishing commences.
Polishing is to be executed by machine and the surface of the paving is to be polished to a fine even surface free from voids or pits.
Polished Granolithic or Terrazzo paving is to be executed by an approved Sub-Contractor.
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WASHED GRANOLITHIC PAVING
Washed granolithic paving shall be mixed and laid as described for polished granolithic or terrazzo paving but the surface is to be lightly brushed with a stiff broom after the initial set has taken place and well washed with clean water to expose the aggregate.
IRONITE PAVING
Ironite paving shall be size graded iron particles as produces by the Ironite Co. Ltd., local agents: Pearson Ltd., Nairobi. The paving shall be laid strictly in accordance with the manufacturer’s instructions using the “three layer construction” method having the top or third layer consisting of 0.5” Ironite laid whilst the screed base is still wet. The topping for heavy duty floor shall consist of the following measured by volume:
1 part Ironite.
4 parts washed concrete sand passing 3/16” screen and passing 100 mesh screen.
4 parts granite chips, graded through 1/4” sieve and retained on 1/8” sieve.
4 parts cement. 4 lbs. ironite per square yard 1/2” thickness.
FLEXIBLE P.V.C. FLOOR TILING
Flexible P.V.C. floor tiling shall be carried out by an approved specialist and shall consist of tiles in accordance with BS 3261, of approved manufacture and colour and to the sizes and thickness indicated in the Drawings or otherwise specified.
The tiles shall be laid to the patterns as indicated (If any) on the drawings with close butt joints and bedded in approved mastic on a clean, dry cement and sand (1:3) screed as before described with a steel trowel finish.
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On completion, any surplus mastic which may have squeezed out of the joints shall be removed, the tiles cleaned with an approved cleaner, and two coats of approved P.V.C. tile sealer applied.
PARQUETRY FLOORING
Parquetry flooring and adhesive shall both be to the Architect’s approval and a sample panel shall be required before commencing this work.
WOOD BLOCK FLOORING
Woodblock flooring shall be to the thickness shown on the drawings or otherwise specified and shall be laid with an approved adhesive. They shall be laid herringbone or basket weave pattern and properly tamped, sanded and polished to approval.
WOODWOOL SLABS
Are to be unreinforced 50 mm thick of standard metric sizes and obtained from National Timber and Hardware Syndicate, P.O. Box 41438, Nairobi or other approved supplier.
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PLASTERING AND RENDERING GENERALLY
All surfaces to be plastered or rendered shall be brushed clean and be well wetted before plaster is applied. All plaster and rendering shall be kept continuously damp for seven days after application. All arrises shall be finished true and slightly rounded except where otherwise stated, and shall be run at the same time as the adjoining plaster. No partially or wholly set plaster or rendering will be allowed to be used or re-mixed.
The Contractor shall prepare samples of the plastering and rendering as directed until the quality, texture and finish required is obtained and approved by the Architect after which all plastering executed in the work shall conform to the respective approved samples.
The Contractor shall cut out and make good all cracks, blisters, and other defects and leave the whole of the work perfect on completion. When making good defects, the plaster or rendering shall be cut out to a rectangular key, and all finished flush with face of surrounding plaster or rendering.
Rates for plastering and rendering are to include for raking out joints of walling or hacking concrete to form a key. Instead of hacking the Contractor will be permitted to treat concrete surfaces, at his own expense, with bonding fluid such as "Plastaweld" manufactured by I. Manager & Son Ltd., or other equal and approved, applied in strict accordance with the manufacturer's printed instructions.
INTERNAL PLASTER
Internal plaster is to be two coat plaster not less than 12 mm thick where the base or scratch coat shall be of one part cement to six parts sand and the finishing coat of lime putty to which has been added 10% by volume of cement prior to application. The surface is to be finished true and level with a wood float.
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BAGGED FINISH
Bagged finish surfaces are to be treated with a complete covering of 1:4 liquid cement/sand wash thoroughly rubbed in to cavities with a sack.
TYROLEAN RENDERING
Tyrolean rendering shall be in two coats. The coat shall be 10mm. thick and consist of a mixture of 93.5 lb. of cement with 10% lime added by volume and four cubic feet of sharp sand applied direct by means of trowel and brought to a level finish with a straight board or rule. No dubbing or scratching is necessary and it is inadvisable to use a float since the surface of this coat should be kept as open as possible. When a rule is used care must be taken to see that it is used in all directions and not in one only, otherwise ridges may be left which show through the Tyrolean finish.
The finishing coat shall be applied by means of a Tyrolean spraying machine and shall consist of white "Concrete" and sand and shall be ascertained by trial. Only sufficient shall be mixed as can be used in one hour.
The finish shall be built up in three layers to a total thickness of 6 mm - 10 mm to give the approved honeycomb texture and shall be applied with a Tyrolean machine in such a manner as to avoid the layers merging into a solid mass.
The whole of the Tyrolean finish shall be executed strictly in accordance with the manufacturer's printed instructions.
WALL TILING
Wall tiles shall comply with BS 1281 : Glazed Ceramic Tiles and Tile Fittings for Internal Walls.
All tiles shall be of the size, colour and quality as described on the drawings and shall be perfectly true to shape and free of all blemishes
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and flaws.
Samples shall be submitted to the Engineer for approval.
All wall tiling shall be fixed on a perfectly true vertical screed of cement and sand (1:3).
Tiling shall be bedded on the prepared screed in a slurry of cement and sand (1:4) or in an approved tile adhesive. The surface of each tile shall finish flush with the adjacent tiles. Joints shall be continuous straight joints both horizontally and vertically not exceeding 1/8" wide and shall be flushed up with white cement. Spacers are to be used to ensure that the correct joint width is maintained.
All cutting shall be kept to a minimum and the tiling shall be set out so that only the largest possible pieces of cut tiles are used.
Purpose made tiles with round on one edge shall be fixed to all vertical external angles and to the top edges of dadoes and the like where these project in front of the wall face over.
BEDS AND BACKINGS
Shall be composed of cement and sand in the proportions stated and applied to walls or floors to the required thickness to receive floor or wall coverings. They shall be trowelled to the density or smoothness required for the particular finish specified.
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GLAZING
GLASS QUALITY
All glass shall be of British manufacture in accordance with BS 952 free from flaws, bubbles, specks and other imperfections cut to size to fit the opening for which it is required with not more than 1/19" play all round.
GLASS GENERALLY
The glass for glazing generally shall be clear sheet and flat drawn sheet and shall be Ordinary Quality (O.Q.) sheet glass. Plate glass where required shall be Glazing Quality (G.Q.) standard plate glass.
GLASS LOUVRES
Glass for louvres shall be of the thickness stated cut to correct sizes with edges rounded and polished.
PUTTY
The putty for glazing shall be tropical putty of approved manufacture suitable for glazing to metal or wood frames as specified.
All putty shall be delivered on site in the original manufacturer's sealed cans or drums and used direct therefrom with the addition only of pure linseed oil if necessary. No mineral or other oils may be used.
The rebates of metal windows shall be painted on coat before puttying. Before glazing, the rebates of all windows shall be adequately back puttied.
The putty shall within 14 days dry and harden without wrinkling of the surface or caking and shall adhere satisfactorily to the surface of the glass and the frame.
GLAZING
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All glazing to wood frames shall be sprigged and to metal frames fixed with clips. All glass shall be properly backputtied, and the front putty finished neatly and cleanly.
The washleather and felt strips shall be approved by the Architect and shall be cut to fit the exact line of bead.
CLEAN ALL GLASS AT COMPLETION
Clean all glass inside and out, remove all paint and putty marks and replace any broken, scratched or cracked panes and leave all glazing sound and perfect at completion.
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PAINTING AND DECORATING
GENERALLY
Painting and decorating shall be executed by an approved Sub- Contractor.
All paints, undercoats, primers and preparatory materials shall be obtained from a source or sources approved by the Architect and must not be varied without express authority given in writing and shall be applied strictly in accordance with the manufacturer's printed instructions or as otherwise directed. All materials shall be delivered on Site intact in the original containers and shall be mixed and applied strictly in accordance with the manufacturer's printed instructions. No addition will be allowed to be made locally without the express permission of the Architect.
The priming, undercoats, and finishing coats shall each be of differing tints, the priming and undercoats shall be the correct brands and tints to suit the respective finishing coats, in accordance with the manufacturer's instructions. All finishing coats shall be of the colours and type specified by the Architect. Before the painting or decorating is started, the Contractor shall arrange that all other trades have been completed and other tradesmen removed from the vicinity of the area to be painted. All plaster, mortar, concrete, oil or stains of any kind shall be removed by the Contractor from work to be decorated before painting commences.
PREPARATION
Plastered and rendered surfaces to be decorated shall be allowed to dry for a minimum of four weeks before decoration commences.
Plaster finished with a steel trowel and fair face concrete surfaces shall be well rubbed down, filled and made good as necessary and thoroughly cleaned down immediately before decoration is applied.
Plaster finished with a wood float or other rough textured surfaces of a similar nature shall be made good as necessary and thoroughly
brushed clean immediately before decoration is applied. Insulation board or similar surfaces shall be filled, and made good as necessary and lightly brushed down to remove all dirt, dust and loose particles.
Metal work to be painted shall be scaled clean and thoroughly wire brushed.
Woodwork to be painted shall be well rubbed down. All knots shall be covered with good shellac knotting before priming and all defects shall be filled with hard stopping after priming. Plywood shall be brushed filled over the entire surface.
Woodwork to receive finishes other than paint shall have all stains removed, be well rubbed down and have all defects levelled up with hard stopping of a colour to match the adjoining surface.
Woodwork to receive clear finish or polish shall be well rubbed down and the varnish is to be applied with a chamois leather pad, rubbed back with fine graded steelwool between coats and afterwards buffed up to produce an approved finish.
PREPARATION OF PELICAN DRYWALLS FOR DECORATION
Prior to decorating the partitions either with paint or wallpaper, it is necessary that the joints, internal and external corners and screws are flush skimmed. Any repairs and joints wider that 5 mm should be prefilled with the recommended plaster (see below). The board surface must also be inspected. Any loose paper must be pulled off and skimmed over with plaster.
1.Butt-Joints Four different skim-jointing gypsum plasters are recommended, depending on the magnitude of the contract and the desired decoration.
1.1 Rhinobed (20 kgs Bags) Rhinobed is used for production joining of Drywall. Rhinobed is applied to the recessed joint and then the jointing tape is bedded into the Rhinobed using a 125 mm taping knife. Ensure that all bubbles are
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removed. Drying time + 10 minutes. Apply a second layer of Rhinobed with a 250 mm trowel. Allow to set and dry.
1.2 Readymix (20 litre Drums) Readymix is used in conjunction with Rhinobed. Readymix is applied over the Rhinobed and tape, using a 300 mm trowel to fill the joint completely flush with the rest of the board surfaces. Drying time + 24 hours, before painting or wallpapering.
1.3 Rhinoglide (20 kgs Bags) Rhinoglide is used for jointing of small drywalls jobs. Rhinoglide is applied in the same sequence as for Rhinobed and Readymix, namely: bed the joint tape into the joint using a 125 mm taping knife. Allow 45 minutes to set and dry. Apply a second layer using 250 mm trowel. Allow 40 minutes to set and dry. Apply third layer suing 300 mm trowel. Again allow 40 minutes to set and dry.
1.4 Rhinolite (40 kg Bags) Rhinolite is used for flush plastering gypsum ceilings and plastering of all internal walls including Drywalls. Rhinolite is specially manufactured as a combined basecoat and finishing plaster and is recommended where a highly polished smooth surface or a textured finish is desired.
2. Internal Corners Apply tape with Rhinobed to internal corner ensuring that the tape is evenly spaced either side. When set or dry apply a second and third coat or Readymix to each side using a 125 mm taping knife. Allow one side to dry before beginning the other side. Alternatively Phinoglide or Rhinolite could be used, using the above method.
3. External Corners Butter the corner bead with Rhinobed. Press firmly into position and secure with drywall screws. Apply a layer of Rhinobed to each side of the corner bead using the 125 mm taping knife. When set and dry apply a second and third layer of Readymix to each side using a 250 mm trowel. Again Rhinoglide or Rhinolite could be used, in the same manner.
4.Screws Screws can be flushed using a 125 mm taping knife. Apply a small
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amount of compound over the screw head in one direction and wipe in a right angle direction. Allow to dry. Apply second and third coat in the same way.
5.General In all points, 1 – 4, it must be remembered to clean off all excess compound and feather out. When all coats are dry, sand lightly using a fine grit sandpaper 100 grit).Do not over sand.
Decoration: Undercoat: A good quality water based emulsion paint must be applied directly to the surface of the Rhinoboard. DO NOT use oil or solvent based undercoats.
Finishing coat: Use any good quality paint.
PLASTIC EMULSION PAINTS
Plastic emulsion paint for internal or external application shall be as recommended by the Paint Manufacturer.
The first coat in each case shall be thinned with 25% water and all subsequent coats applied undiluted.
BITUMINOUS SOLUTION
Bituminous solution for use on coated pipes shall be of approved manufacture.
PRIMERS
Unprimed steelwork shall be primed with Red Lead Primer.
Galvanised steelwork shall be primed with Zinc Chromate Primer.
Woodwork shall be primed with an approved Wood Primer.
UNDERCOATING
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The Undercoat for use under enamel finishing coats shall be of approved quality as recommended by the Manufacturer.
ENAMEL
Enamel finishing coats shall be of approved manufacture and in accordance with the colour chart.
METHOD OF APPLICATION
After each coat the work shall be allowed to dry and shall then be well rubbed down with fine glass paper on blocks or other means as required for the particular work before the next coat is applied. The paint work shall be finished smooth and free from brush marks.
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GENERAL SPECIFICATIONS PART III
ELECTRICAL AND MECHANICAL WORKS
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GENERAL SPECIFICATION FOR PLUMBING INSTALLATION
GENERAL REQUIREMENTS
1.01Introduction This specification details the requirements for the materials supply, installation, testing and commissioning of the Plumbing and firefighting installation as shown on the Contract Drawings.
The Sub-Contractor shall include for all appurtenances and appliances not necessarily called for in this specification or shown on the Contract Drawings but which are necessary for the completion and satisfactory functioning of the contract works.
If there is a difference between the requirements of this Specification and the Contract Drawings or lack of clarity in either specification or the Contract Drawings, the Contractor must clarify such differences with the Engineer before tendering. No claim for extra payments shall be entertained from the Contractor due to failure to comply with this requirement.
1.02Scope of Works The Sub-Contract works shall comprise the supply and installation of all the sanitary appliances, the internal drainage system up to the nearest man- hole outside the building, the internal cold and hot water supply and storage system, the external water reticulation system, together with the installation of the firefighting equipment all as shown on the Contract Drawings and as here-in specified.
Regulations and Standards All the Plumbing works shall be carried out by a licensed and experienced plumber under the Government Regulations. The work shall be executed in accordance with the best principles of modern plumbing practice.
The Contractor shall be responsible for ensuring compliance with all the governing regulations and in particular, his attention is drawn to the following specific codes and regulations:-
The Local Authority by-laws and regulations
The current Republic of Kenya Building Code The M.O.W latest issue of “General Specification for Building Works” B.S. 5572 - Code of practice for sanitary pipework B.S. 8301 - Code of practice on building drainage B.S. 6465 - Sanitary Appliances B.S 5955 - Code of Practice for uPVC pipework C.P. 310 - Water Supply B.S. 6700: 1987 - Water supplies within buildings The I.E.E Regulation The Kenya Bureau of Standard (K.B.S) Specification
All plumbing shall be executed in accordance with Regulations of the Local Authorities and the Water Supply Companies. The Contractor shall give all Notices and pay all fees required thereunder. The amount of such fees shall be deemed to be included in the Contract Sum unless otherwise expressly stated.
Occupation Certificate The plumbings Contractor shall upon completion obtain an “Occupation Certificate” from the Local Authority and forward it to the Engineer. The cost of obtaining the certificate shall be deemed to be included in the Contract Sum.
1.5 Materials and Standards All equipment and materials shall be new, strong and of durable construction. All the items must meet the relevant quality standards and of reputable manufacture. Safety devices such as pressure relieve valves, thermal expansion joints, thermal and over-load protectors etc must be installed wherever deemed necessary.
1.6 Builders Work Holes, trenches and wall chase in building fabric to accommodate pipes, cable trays etc., together with concrete plinths for pumps, tanks etc. shall be carried out by the Main Contractor at no cost to the Sub-Contractor. However, the Sub-Contractor must inform the Main Contractor of his requirements well in advance to allow such requirements to be incorporated before casting of the building fabric. Drill holes in concrete for anchor channels, clamps, supports etc. shall be carried out by this Sub-
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Contractor but he must liaise with the Main Contractor before carrying out such works. The Sub-Contractor shall not make any holes nor cut the building fabric without the express consent of the Structural Engineer and consultation with the Main-Contractor.
Water meters These shall be to BS 5728 part I and I.S. 4064/1. The meters shall be suitable for water temperature upto 30 O C and 10 bar Nominal pressure. These shall have counter registration in cubic meters (or liters), and be able to register down to 1 litre of water volume. These shall be installed to the requirements of BS 5728 part 2 and to the approval of the local council. The subcontractor shall on behalf of the client apply for and secure the meter connection from the Local Authority. He shall therefore allow for all the costs for permits, materials and attendance in connection thereof.
WATER SUPPLY INSTALLATION:
Galvanised Mild steel pipes
Tubing shall be galvanised mild steel to B.S. 1387, with tapered pipe thread to B.S 21:1985. These shall be medium gauges for general use and heavy gauge for underground use, with screwed and socketed joints and of approved manufacture. Tubes must be cleanly finished with smooth surfaces, free from defects and scales.
All pipes below ground are to be protected by coating with bitumen reinforced with glass fibre tissue, hessian cloth or other approved material.
Fittings shall be galvanised wrought steel to B.S 1740, with B.S. thread, or galvanised malleable cast iron to B.S. 143 and 1256, of approved manufacture, for use with galvanised steel pipes to B.S. 1387. Castings must be smooth and free from blow holes, pittings and other defects.
Where flanged connections are used, these shall comply with B.S. 4504, welded or screwed .All flanges shall withstand a Nominal pressure of 1.6 Mpa (PN 16) and shall be of either grey cast iron or steel.
Flanged joints shall have gaskets complying with B.S. 4865 part 1 of 1972,
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for pressures upto 6.4 Mpa (64 bars). Galvanising of pipes and fittings shall be to B.S. 729:1971
2.2 Copper Pipework Copper pipes shall be used to B.S. 2871:1971 part 1, of approved manufacture. These must be solid drawn, round, clean, smooth and free from all defects and deleterious films in the bore. Fittings shall be capillary or compression type to B.S. 864:1983 Part 2, of approved manufacture, free from internal fins and designed for minimum resistance of fluid flow. Compression fittings to be type A (Non-manipulative), unless otherwise specified. Copper tubing is to be used as shown on the drawings and as connection tube between steel pipe work and sanitary / laboratory fittings.
In order to avoid direct contact a brass straight connector shall be positioned between the steel tube and the copper tube.
u.P.V.C. Cold Water Service Pipe System Pipes shall comply in all respects with British Standard 3305:1968 and shall bear the British Standard Kite Mark together with the appropriate class colour coding at one metre intervals.
Fittings shall comply in all respects with British Standard 4346 Part 1:1969 and shall bear the British Standard Kite Mark.
Pipes shall be supplied in plain-ended lengths.
The minimum acceptable wall thickness of pipe and fittings shall be as follows:
12mmnominal1.7mm40mmnominal3.1mm 20mmnominal1.9mm50mmnominal3.9mm 25mmnominal2.2mm75mmnominal5.7mm 30mm nominal 2.7mm 100mm nominal 7.3mm
The method of jointing to be employed for dimensions 40mm and smaller shall be that of solvent welding socket using the
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manufacturers approved solvent cement.
For dimensions 50mm and larger the method of jointing shall be with lock-ring integral socket and coupling.
The grade of Polymer used for the pipe shall have a minimum softening point of 75 C and for the fittings a minimum softening point of 72C when tested by the ‘Vicat’ method 102J and a Tensile strength of Min. 45MN/m2 at 20 C as described in British Standard 2782:1975. The pipes and fittings shall be colour grey.
Valves, Taps and Ball-valves a) Brass stop valves and draw-off taps (bibtaps, pillar taps
combination taps etc) shall be to B.S. 1010 Part 2:1973 or B.S. 5412; screw-down pattern, to comply to test pressure of 2.0 Mpa (20 Bars) and of approved manufacture.
b) Draw off taps shall be of metal body with chromium plated finish unless otherwise specified.
a) Copper alloy valves (gate, globe, stop and check valves) shall be to B.S. 5154 and tested to B.S. 5146 Part 2; 1984. These shall be with screwed, flanged or capillary compression ends. fLanged check valves shall be to B.S. 5153:1974 as type Glenfield No. 5003. The body, door cover to be of meehanite cast iron with fun- metal seat to B.S, 1400.
a) Gate valves of sizes above 80mm shall be of cast iron wedge type to B.S. 5163:1974 as Glenfield R.S. No. 3500 series. These are of meehanite cast iron body to B.S. 1452 with rubber covered meehanite cast iron gate.
a) Brass draining taps to be screw down pattern to B.S. 2879:1980, type A (Bushed) unless otherwise specified.
a) Ball valves shall be of brass body and to B.S. 1212 Part 1:1953 piston type for low, medium or high pressure (3.58 bars, 7.72 bars and 12.62 bars respectively) as directed and with provision for removable seats, supplied with copper floats to B.S. 1968:1953, or
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plastic floats to B.S. 2456., approximately marked.
Pipe Thermal Insulation All exposed and under-ground hot water and chilled water supply pipes and fittings shall be adequately thermally insulated. The insulation shall be to B.S. 5422:1977, and B.S. 5970:1981. The insulation shall be pre-formed fibre-glass insulation for hot water and steam, and expanded polystyrene (styropor) in sections for chilled water.
The insulation shall be covered with proprietary cladding material or, where no proprietory material exists, with cotton canvas for indoor pipework and o.25mm thick aluminium sheet or foil for external and under-ground piping. The sheet jointing shall be water proofed to the Engineers approval. Underground Cladding shall be finished with two coats of bituminous painting.
Pipe insulation thickness for hot water supply shall be as given in the table below; and the density of the fibre glass shall be 100 kg/c.m., and 0.045 w/m2 oC declared max. thermal conductivity.
Pipe diameter 15-20mm25-80mm100-200mm
Insulation thickness20mm25mm30mm
All lagged pipes which run in a visible position after erection shall be given a canvas cover prepared for painting as follows:
a) Apply a coating of suitable filler until the canvas weave disappears and allows to dry.
b) Apply two undercoats of an approved paint and finish in suitable gloss enamel to colours approved by the Engineer.
All lagging for cold and hot water pipes erected in crawlways, ducts, and above false ceilings which, shall be covered with a reinforced aluminium foil finish and banded in colours to be approved by the Engineers.
In all respects, unless otherwise stated, the hot and cold water installation shall be carried out in accordance with the best standards
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of modern practice as described in C.P. 342 and C.P. 310 respectively, to the approval of the Engineer.
Hot water pipes chased in walls shall be wrapped with hair felt or tobacco paper and secure with copper wire.
Jointing of Water Supply Pipework a) All joints must be air tight and water tight. b) Compounds containing red-lead shall not be used in jointing water
supply pipes. c) Steel pipes shall be screwed together using an approved
compound/proprietary thread tape. Exposed threads above ground shall be rust-proof painted using non-toxic bituminous paint while those to be buried shall be thickly coated with bitumen.
a) Joints of copper to steel pipes of less than 38mm diameter shall be by copper unions or union ferrules. Those of 38mm diameter and above shall be by screw, braze, or weld copper flange to copper pipe jointing to steel flange with copper allow bolts and nuts.
Before any joint is made, the pipes shall be hung in their supports and adjusted to ensure that the jointing faces are parallel and any falls which shall be required are achieved without springing the pipe.
Where falls are not shown on the drawings or stated elsewhere in the specification, pipework shall be installed parallel to the lines of the building and as close to the walls, ceilings, columns, etc., as is practicable.
a) All water systems shall be provided with sufficient drain points and automatic air vents to enable them to function correctly
Before any joint is made, the pipes shall be hung in their supports and adjusted to ensure that the jointing faces are parallel and any falls which shall be required are achieved without springing the pipe.
Where falls are not shown on the drawings or stated elsewhere in the specification, pipework shall be installed parallel to the lines of the
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building and as close to the walls, ceilings, columns, etc., as is practicable.
All water systems shall be provided with sufficient drain points and automatic air vents to enable them to function correctly. Valves and other user equipment shall be installed with adequate access for operation and maintenance. Where valves and other operational equipment are unavoidably installed beyond normal reach or in such a position as to be difficult to reach from a short step ladder, extension spindles with floor or wall pedestals shall be provided. Screwed piping shall be installed with sufficient number of unions to facilitate easy removal of valves and fittings, and to enable alterations of pipework to be carried out without the need to cut the pipe.
Full allowance shall be made for the expansion and contraction of the pipework, precautions being taken to ensure that any forces produced by the pipe movements are not transmitted to valves, equipment or plant.
All screwed joints to piping and fittings shall be made with P.T.F.E tape or Boss white proprietory compound.
Expansion Joints and Anchors Where practicable, hot water pipework systems shall be arranged with sufficient bends and changes of direction to absorb pipe expansion providing that the pipe stresses are contained within the working limits prescribed in the relevant B.S. Specifications. Where piping anchors are supplied, they shall be fixed to the main structure only. Details of all anchor design proposals shall be submitted to the Engineer for approval before erection commences.
When arranging piping it shall be ensured that no expansion movements are transmitted directly to connections and flanges on pumps or other items of plant.
Flexible joints shall be supplied to prevent vibrations and other movements being transmitted from pumps to the piping systems or vice versa.
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All bends, valves and hydrant tee etc. in the line of the water mains shall be adequately anchored to resist thrust due to internal water pressure. A concrete block shall be cast under and the around the pipe and between it and the sides of the trench. Well rammed materials shall be used to support the pipe on either side of the concrete.
Pipe Supports and Fixings (a) General This sub-clause deals with pipe hangers, slider and roller type supports, clamps, cages, cantilevers etc supports securing pipes to the structure of buildings for above ground application. These shall be manufactured to B.S. 3974.
The variety and type of supports shall be kept to a minimum and their design shall be such as to facilitate quick and secure fixings to metal, concrete, masonry or wood.
Consideration shall be given, when designing supports, to the maintenance of desired pipe falls and the restraining of pipe movements to a longitudinal direction only.
Pipes shall be fixed in a position which leaves the lower surfaces at the same horizontal level, unless otherwise instructed.
Pipes shall be fixed to true lines parallel to adjacent lines of the building unless otherwise specified.
Where insulated, pipes shall be fixed with the insulation at least 25mm clear of adjacent surfaces.
The Plumbing Contractor shall apply and install all steelwork forming part of the pipe support assemblies and make good any damage to builder’s work associated with the pipe support installation.
All proposals for pipe supports shall be submitted to the Engineer for approval before any erection work commences.
b) Spacing for Pipe Supports
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Pipe runs shall be secured by pipe clips connected to pipe hangers, wall brackets or trapeze type supports. ‘U’ bolts shall not be used as a substitute for pipe clips without the prior approval of the Engineer.
An approximate guide to the maximum permissible supports spacings in meters for steel and copper pipe and tube is given in the following table for horizontal runs.
Size Nominal Bores
Copper Tube To B.S. 2871
Steel Tube To B.S. 1387
15mm 1.25mm 2.0m
20mm 2.0m 2.5m 25mm 2.0m 2.5m 32mm 2.5m 2.7m 40mm 2.5m 3.0m
50mm 2.5m 3.0m 65mm 3.0m 3.5m 80mm 3.0m 3.5m 100mm 3.0m 4.0m 125mm 3.5m 4.5m 150mm 4.5m 5.5m
The Support spacings for vertical runs shall not exceed one and half times the distances given for horizontal runs, or as given by the manufacturers.
b) Pipe Sleeves Where pipes pass through concrete or block wall, pipe sleeves of galvanised steel tube shall be used; these shall be of sufficient sizes to give at least 3mm clearance around the pipe. The annular space shall be filled with bitumastic material and caulked at the ends.
Trench Excavation – Water Main As described in B.S 8301 Clause 18 and the following:-
(a)The Contractor shall excavate the pipe trenches in the line to the depths indicated by the Engineer. Except where otherwise indicated on the drawings or directed by the Engineer, all pipes
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must have a minimum cover of 500mm over top of the barrel of the pipe when laid, plus or minus a tolerance of 75mm either way. All trenches shall be excavated in open cuttings.
(a)Where the trench passes through grassland, arable land or garden, whether enclosed or otherwise, the turf, if any, shall be pared off and stacked, and the productive soil shall be carefully removed from a width of 600mm greater than the normal trench width, or equal to the overall width of track of the excavating machine whichever is greater, and laid aside to be subsequently used in reinstating the surface of the ground after the trench has been refilled.
(a)The bottom of the trench shall be properly trimmed off, and all low places or irregularities shall be levelled up with fine material. Where rock or large stones are encountered, they shall be cut down to a depth of at least 75mm below the level at which the bottoms of the barrels of the pipes are to be laid, and covered to a like depth with fine material (sand or red soil) so as to form a fine and even bed for the pipes.
(a)Joint holes shall be excavated to such minimum dimensions as will allow the joints to be well and properly jointed.
(a)The pipe trench shall be kept clear of water at all times.
(a)The Contractor shall, wherever necessary, by means of timbering or otherwise, support the sides of the trench so as to make them thoroughly secure, and afford adequate support to adjoining roads, lands, building and property, during the whole time the trench remains open and shall remove such timbering when the trench has been backfilled. The cost of such timbering or other work shall be deemed to be included in the rates for excavation and backfilling. In case the Contractor is instructed by the Engineer to leave any portion of such timber in position, he will be paid for it accordingly.
(a) The clear width inside the timbering, in the case of single pipes shall be at least 320mm in excess of the external diameter of the
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pipe being laid, in order to allow it to be freely lowered into position in the trench without damage to the external protection.
(a) Where more than one pipe is to be laid parallel, then the clear width inside the timbering shall be at least 520mm in excess of the combined external diameters of the pipes.
(a)Any excavation below the specified depth, in error or otherwise, shall be refilled to the correct levels, at not extra cost, with mix 1:3:6 concrete or other approved material.
(a)If a mechanical excavator is used by the Contractor, he shall indemnify the Employer against all claims for damage which, in the opinion of the Engineer, may have been caused by the use of this plant. When a mechanical excavator issued the bottom 200mm of excavation shall be excavated by hand to ensure an even bed for the pipes.
Concrete Bedding, Haunching and Surround Concrete bedding, haunching and surround shall be provided as necessary of where called for by the Engineer in accordance with the requirements laid down in B.S. 8301:1985 Clause 11.
Backfilling Backfilling of trenches, shall be carried out in accordance with the methods described in B.S. 8301:1985 Clause 5.7.6.
Reinstatement of Surfaces Following the final backfilling of all trenches and manhole surrounds, the surface of the excavated areas shall be fully reinstated to the approval of the Engineer.
Where the excavations have been carried out in public highways or other areas not forming part of the site, prices will be deemed to allow for all charges associated with the temporary and final reinstatement requirements of the Local Highway Authority.
No claims for extras in this respect will be accepted.
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Identification of Pipelines All pipes conveying fluids shall be identified by applying the basic identification colours or the colour code indication as specified in B.S. 1710. The following table is given as a guide.
Pipe Contents Basic identification colour 1. Water Green 2. Drainage Black
3. Steam Silver Grey 4. Fire extinguishing Red 5. Compressed air and
vacuum Light Blue
6. Oils Brown 7. L.P.Gas Yellow
The method of application shall be as here-in specified and/or shown on the drawings.
Lettering The lettering for sluice valves, fire hydrants, air valves and washouts abbreviated SV, FH, AV and WO respectively shall be in accordance with the normal practice and as details shown on the drawings and colour coded as above with letters in white or black on the appropriate background colour.
Surface Boxes Sluice valves, air valves and fire hydrants shall be covered with surface boxes in accordance with details as shown on the drawings. In roads and footpaths the boxes shall be laid flush with the surface.
Water Supply Pipework Testing The whole of the water supply system shall be tested to the approval of the Engineer as follows:-
Plug-off valves of main service line and/or terminals in the section to be tested. Fill pipes with drinking water and apply test pressure which shall be the maximum working pressure plus 50%, or as directed by the Engineer.
There must be no measurable loss of pressure at the end of one hour and system must be water tight. Open all taps and check for satisfactory rate of outflow. Test all cisterns as directed, at pressure not less than the working pressure. Locate and make good all defects and re-test to the satisfaction of the Engineer.
Testing – Mains Installation
(a)The test pressure shall be one and a half the maximum working pressure except where a pipe is manufactured from a material for which the relevant B.S. Specification designates a maximum test pressure as in the case of the cast or spun iron pipes, where the test pressures should not exceed 120, 180 and 240 metre/head for Clause B, C, or D pipes, respectively.
The test pressure shall be maintained by the pump for about one hour and if there is any leakage, it shall be measured by the quantity of water pumped into the main in that time.
(a)When a section of the main has been jointed, the ends shall be closed with caps, plugs, or flanges which must be strongly strutted against a solid surface to the satisfaction of the Engineer. The trench shall be properly backfilled and rammed as herein specified, and as shown on the drawings, for its whole length so as to cover the main to a depth of not less than 500mm, except at the joint places which shall be kept clear of all backfilling, if necessary by the use of timbering, so that each joint is left fully exposed for inspection. No backfilling of joints will be permitted before testing of each section.
As long as a section of main as possible shall be tested at one time subject to the maximum length of open trench approved by the Engineer or permitted by the Highway Authority, and the test shall be carried out within 12 working days of the completion of such sections of mains.
Where a main is laid across a road or in such as position as to
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interfere seriously with the normal use of the road, the Contractor may, with the consent of the Engineer and at his own risk, fill in such joint holes as may be necessary. He shall, at his own expense, re- excavate any or all joint holes necessary to locate a leak and carry out repair work should the results of his hydraulic test prove unsatisfactory.
The section shall then be filled with mains water, great care being taken to drive out all air through air valves ferrules or otherwise to the approval of the Engineer.
(a)After the section to be tested has been charged and all air liberated it shall remain standing under moderate pressure for several days for final airing.
The leakage from the mains and connections from each section tested shall not exceed 4 liters of water per 25mm diameter of main, per 2 km length each 24 hours, every 30 meters head of pressure, and any visible individual leak shall be repaired.
To determine the rate of leakage, the Contractor shall furnish a suitable hydraulic test pump, pressure gauge, connections and water meter or other appliance, for measuring the amount of water pumped.
If the leakage to be at a greater rate than that specified the Contractor shall re-excavate the trench where necessary and shall remake the joints and replace defective work until the leakage shall be reduced to the allowable amount.
(a) The Employer shall charge the Contractor the cost of any couplings required to join up tested lengths of main if, in the Engineer’s opinion, greater lengths could reasonably have been tested or if failure under test requires the pipe to be cut, or other methods of laying should have been adopted.
Water used by the Contractor in testing the main shall be supplied by the Main Contractor. The Contractor shall carry out all work which may be necessary for making temporary connections to the existing mains to obtain water for testing at his own expense.
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(a) In carrying out the test for watertightness the Engineer only shall authorise the operation of all valves, but the Contractor shall provide all the necessary labour to assist in the opening and closing of the valves to the Engineer’s instruction, and he shall allow in his prices for all his expenses in connection with testing on completion.
The Engineer shall be the sole judge of watertightness.
Sterilization of Installation After testing, all the water supply system shall be sterilized before taking into use, and after being opened up for any repairs.
Sterilizing shall be done in accordance with C.P. 310:1965 Clause 409, or as detailed below, to the satisfaction of the Engineer.
a) Fill the whole system with drinking water and flash out.
a) Re-fill the system, adding sterilizing chemical gradually as the storage cistern fills. Use proprietary chemicals, or bleaching powder at the rate of 0.15 kg per 1000 liters.
a) When the cistern is full, open the taps successively working away from the cistern, and closing each tap as the discharge begins to small chlorine.
a) Top up the cistern with water and the sterilizing chemical and leave still for 24 hours.
a) Empty system and flush-out thoroughly with clean water.
Cleansing and Sterilizing the Mains When a pipeline is complete and where applicable, has successfully passed the test, it shall be thoroughly washed out using, if possible an open end. Thereafter it shall be sterilized by being filled with a suitable solution containing not less than 20 p.p.m of free available Chlorine or such other sterilizing agent, as the Engineer shall prove. After standing for 24 hours the main shall again be washed out and
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refilled with main water prior to the taking of bacteriological samples. The Contractor shall provide all necessary stop ends, fitting and chemicals for this work.
Empty and washing out of the pipes shall be done in such a manner as not to damage the trench or cause flooding, and the Contractor shall supply and use such piping, specials and/or hose as may be necessary to facilitate the flow of water to the nearest drain or watercourse. Water used for washing out and sterilizing will be supplied by the Main Contractor.
Before any section of the main is put into use a bacteriological sample or samples will be taken in the presence of the Engineer and only on receipt of satisfactory certificate from the Medical Research Laboratory will the main or section of main be permitted to be put into supply and be considered as having been substantially completed.
Any expenditure involved in providing facilities or materials for the taking of samples shall be included in the Contractor’s tendered rates and the Engineer will specify and shall be the sole judge as to the number of samples required and the points at which they are to be taken.
The cost of the bacteriological examination will be borne by the Employer but if the sample or samples are not satisfactory the cost of any subsequent analysis will be borne by the Contractor.
Existing Installation Where pipes for cold water are to be connected up to existing installations, the condition of the existing installation it to be reported to the Engineer in order to establish if part of the existing installations is to be replaced or serviced. The Sub-Contractor shall allow for keeping the services in use with minimum interruptions. All service interruptions must be reported and agreed to with the client at least 24 hours in advance.
Clearance of the Site The Contractor shall remove all surplus pipes, specials and other fittings from the site, upon completion of the works and prior to
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handing over. The site of works shall be levelled and all surplus excavation, debris, cut trees or bushes shall be carted to approved tip sites.
Booster Pumps These will comprise of 2 No. Electrically driven pumps, one for duty and one for standby. The pump vital parts (seal drivers, head cover, intermediate chamber, impeller, shaft, washer outer sleeve etc.) shall be in stainless steel, with tungsten carbide seal ring and cast iron pump head and a maintenance free mechanical shaft seal. This shall be coupled to a totally enclosed squirrel cage 2 pole fan cooler motor.
Flange connections on each pump are to be BS 4504NP.16.
Each pump is to be supplied with isolating valves, non-return valves and test cocks on the pump body, all as shown on the drawings or elsewhere in this specification.
The pump and motors are to be assembled on a mild steel fabricated support base plate which is to be bolted down to a concrete plinth in an approved manner.
Flexible coupling with flange connections are to be supplied and fitted to both suctions and delivery pipes to reduce pump vibrations being transmitted via the connection pipework.
PUMP CONTROL PANEL The control panel shall house the pump motor starters, selector switches, alarm devices and overload protection gear together with a micro-door switch to isolate all power upon opening the panel door.
The panel shall be fabricated from heavy duty sheet steel with stove enamelled finish and clear Perspex front cover, forming a dust and damp proof enclosure.
All control buttons and indicator lights shall be mounted on the panel door and suitably labelled and shall include the following:-
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a) Main isolator switch b) Pump No. 1 switch on push button c) Pump No. 2 switch on push button d) Automatic and manual change-over switches e) Pump running (green light) indicator light for each pump f) Pump failure
DRAINAGE SYSTEM
MATERIALS AND WORKMANSHIP
Cast Iron Spigot and Socket Pipes These shall conform to B.S. 416:1973 for above ground pipework and of approved manufacture. Castings must be sound and free from defects, and must ring clearly when struck with a light metal hammer. All pipes and fittings to be coated with tar or bitumen based solution suitable for tropical conditions by the manufacturer.
Jointing shall be by packing the joint space with a gasket of firmly caulked tarred yarn, then caulked with molten lead or fibrous lead yarn.
Cast iron socketed pipes shall generally be supported at every socket joint by means of either holderbats secured rigidly to the structure, or purpose made straps for attachment to rigid steel support brackets.
When holderbats are used, they shall conform to the requirements of B.S. 416.
Suitable anchors shall be provided at all changes of pipe direction, junctions and tees, to counteract the effect of end thrust loads.
All cast iron pipework, branches, tees, bends and other fittings shall be supplied complete with inspection covers for cleaning purposes. These inspection covers shall be included as part of the fittings and shall comply with the requirements of B.S. 146.
u.P.V.C. Soil and Water System The pipes and fittings shall comply in all respects to B.S.S. 4514 and
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B.S 5255 and shall where appropriate bear the British Standard Kite Mark. Pipe will be supplied in plain ended lengths. The minimum acceptable wall thickness of pipe and fittings will be as follows:-
32mm pipe1.8mm 40mm pipe1.9mm 50mm pipe2.0mm 80mm pipe3.20mm 100mm pipe3.20mm 150mm pipe3.30mm
The method of jointing to be employed shall be that of solvent welding using the manufacturers approved cement. Seal ring fittings shall be used where necessary to accommodate thermal movement, or the sockets of standard fittings shall be converted to seal ring joints by the addition of a seal ring adaptor.
The grade of Polymer used for the pipe shall have a minimum softening point of 82 deg. C and for the fittings a minimum softening point of 79 deg. C when tested by the ‘Vicat’ method 102D as described in British Standard 2782:1975.
The pipe and fittings shall be colour grey, to British Standard 5252:1976, 10.A.07 with the exception of water closet connections, which may be colour white.
The rubber seals for seal ring joint shall be of ‘W’ section and shall be to the material requirements of British Standard 2494:1976. Water closet connections shall be to the same British Standard.
Water boss connections when fitted to pipes shall consist of two parts with inner and outer flanges, solvent welded as a complete unit with inbuilt gradients for the waste pipes of 1.25 degrees. Where it is not possible to gain access to the bore of the soil pipe, self locking bosses with integral clamping action may be used provided that the mating surfaces are suitable for and used with solvent weld cement.
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Water boss connections to branch fittings as necessary shall be solvent welded to set positions of its branch fittings. Alternative waste boss connections may be made using unequal junctions conforming to British Standard 4514:1969 with solvent weld joints conforming to the same.
Holderbats shall be made of mild steel protected from corrosion by galvanising. They shall have a two position fixing suitable for either acting as pipe support but allowing thermal movement or as a clamp fit on a fitting creating a fixed point. For optimum fit to pipe supports P.C.V packing pieces may be used.
Access shall be provided when necessary either by means of an integrally moulded door in an access fitting with an externally fitted rubber seal and secured with two galvanised bolts and nuts or alternatively two-piece clamp type door fitted into the pipe run. The system shall be as described in a ‘Product Handbook’ complying with the recommendations of B.S. 4940:1973.
u.P.V.C. Rainwater Fittings All fittings shall be injection moulded and shall be compatible with pipes and gutters/
All gutters, pipes and fittings shall be colour grey to British Standard 5252:1976 10.A.07, or black or white.
Gutter connecting fittings shall have integrally moulded seal retaining cavities housing a polychloroprene seal of hollow section.
The fittings shall incorporate a gutter retaining clip:-
Gutter connecting fittings shall incorporate provision for fixing the fascia boards, rafters or blockwork such that the fixing screws shall not be in contact with the inner surface of the gutter and shall have provision for expansion of the gutter clearly marked in the fitting.
The grade of Polymer used for pipes and fittings shall have a minimum softening point of 75 deg.C when tested by the ‘Vicat’ method 102J as described in the British Standard 2782:1975.
Gutters shall be supported on support brackets at one metre centres.
Gutters shall be installed to accommodate thermal movement.
Expansion joints shall be provided at maximum 4 metre centres.
All rainwater system shall be installed in accordance with the manufacturer’s site work instructions.
u.P.V.C Underground Drainage System
The pipes and fittings shall comply in all respects to British Standard 4660:1973 and shall bear the British Standard Kite Mark.
Pipes shall be supplied win plain ended lengths.
The minimum acceptable wall thickness of pipe and fittings will be as follows:-
80mm pipe 2.25mm 110mm pipe 3.2mm 160mm pipe 4.10mm 80mm junction 3.2mm 110mm junction only3.50mm socket 3.80mm body All other fittings 3.20mm socket 3.40mm body 160mm all fittings 4.30mm socket 4.70mm body
The method of jointing to be employed shall be solvent weld or lip- seal socketed fittings. Jointing to other materials shall be made in the manner specified by the manufacturer.
The grade of polymer used for the pipe shall have a minimum softening point of 82 deg. C when tested by the ‘Vicat’ method 102D as described in British Standard 2782:1975, and for fittings 79 deg.C.
The pipes and fittings shall be of colour golden brown approximating to British Standard 381C:1971 No. 414. The seal retaining caps and
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seal rings shall be black .
The rubber for lip seal joints shall be to British Standard 2494:1976.
The base of soil and vent stack connection to the below ground drain shall be made with a bend of minimum centre line radius 250 mm.
Minor changes of direction where permitted shall be made with a variable bend.
Where pipes are laid under floor slab, these shall be laid on 150mm thick concrete class “15” (1:3:6 mix) bed on full width of trench or min. 400mm wide, and the pipe shall be completely surrounded with similar concrete thickness. In all other cases, the pipes shall be laid on prepared ground in trench and backfilling to manufacturer’s recommendations. Pipes shall not be left exposed to the sub during construction period.
Waste Fitment Traps a) Standard Traps These shall be generally of the same diameter and material as the waste outlets to which they are connected to or as specified on the drawings. All wastes shall comply to B.S. 3380.
Wastes connected to main drains through an intermediate gully trap may have a trap with a minimum water seal depth of 40mm. All other traps shall have a water seal of minimum depth – 75mm. Bottle traps shall not be used for waste connections to sinks.
Copper and copper alloy traps shall be case, solid drawn or hot formed to B.S. 1184.
Plastic traps shall be B.S. 3943, of approved manufacture. These and the uPVC pipe work must be supplied by the same manufacturer.
a) Anti-Syphon traps Where specified, anti-syphon traps shall be as manufactured by “Caradon Terrain Ltd”, self-resealing type or by “Marley Extrusions
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Ltd”, Anti-syphon type, or equal and approved.
Sealing off Existing Drains and Manholes Existing foul, surface water and sub-soil drains exposed during progress of work are to be reported to the Engineer. Where not required to be reused seal off with concrete or grout solid as directed. Seal off connection to manholes, demolish walls to 500mm below surrounding ground level and fill remainder of manhole with consolidated approved rubble and cover to level of surrounding ground as directed.
Drain Trenches Excavation of trenches shall be made to such depths as shall be required to obtain proper falls and firm foundation. No permanent construction shall be commenced on any trench until the excavation has been approved by the Engineer. Where trenches have been excavated below the required depths they shall be re-filled to the correct level with Class “10” mass concrete (1:4:8 mix) for indoors and compacted granular or other approved fill for outdoors. Backfilling of the pipe trenches shall be by soft material free from stones and shall be watered and carefully tamped over and around the pipe concrete surround in 300mm layers until they are covered to a depth of 600mm. Subsequent filling is to be in 150mm layers, watered and rammed.
Cast Iron Man-hole Covers and Frames Covers and frames shall be to B.S. 497, of approved manufacturer. Covers are to be cleanly cast, free from air-holes, sand holes and voids, and to fit well in the frame. Covers and frames shall be coated using hot applied coal-tar based material complying with B.S. 4164:1980.
Unless otherwise specified, covers are to 600 x 450 mm, single or double seal, flat type or recessed top for light or medium duty as specified on the Contract drawings. Heavy duty as “ East Africa foundry works” Medium duty (Grade B):Minimum weight 143 Kg. Light duty (Grade C): Minimum weight 37 Kg.
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Step irons for deep man-holes, where specified shall be of cast iron to B.S. 1247.
Sundries Galvanised steel wire baloons shall be B.S. 416, table 22, of approved manufacture. Vent cowls, weathering slates and aprons for uPVC piping shall be supplied from the manufacture of the plastic pipeworks system.
Fixing of all pipework shall be by holder-bats, pipe-rings and fixing clips, screwed, nailed or bolted to the structure to manufacturers recommendations and to the Engineer’s approval.
Inspection and Testing All inspection and testing shall be carried out as laid down in B.S. 5572:1978 and to the Engineer’s approval. All apparatus and water for testing shall be provided by the Contractor.
Drainage pipework shall be tested as soon as practical after erection. Concealed pipework shall be tested to approval before enclosing.
Testing shall be carried out as follows:-
a) Carry out air-test as described in B.S. 5572, Clause 12.3.1. b) Carry out water test as described in B.S. 5572, Clause 12.3.2.3. c) Carry out performance tests as described in B.S. 5572 Clause
12.3.3.
Keep record of all tests carried out for inspection by the Engineer.
SANITARY APPLIANCES
General
All sanitary appliances shall be installed in accordance with the best standard of modern practice as described in B.S. 6465, and to the
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approval of the Engineer.
The appliances shall be as here-in specified and as described on the Contract drawings. The item specification is given as a guidance only, including manufacturers reference numbers, but the Contractor shall ascertain and procure all the necessary accessories specified or not, but which are required for complete installation and proper functioning of the appliance. The Contractor shall also ensure that all items ordered comply with the general regulations, standard and by- laws as specified in this document.
Where specific items are unobtainable, the Engineer shall be entitled to reject any of the alternatives on grounds of appearance or for any other reason, notwithstanding compliance with the terms of this specification.
Protection Protection covers for the appliances etc shall be retained during and after fixing as far as possible.
None of the equipment for the Contract works shall be used for preparing or soaking materials for washing tools, disposing waste or for any other purpose for which they are not designed.
All appliances must be stored under cover and kept dry prior to installation.
Where existing sanitary fittings are to be removed or replaced, the fitting is to be removed with utmost care and all fittings and taps to be handed over to the Employer.
Fixing All fixtures shall be fixed in accordance with the manufacturer with the manufacturer’s recommendations and to the Engineer’s approval.
Fastenings and fixings supplied by the equipment manufacturers shall be used wherever possible.
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TECHNICAL SCHEDULE
The Tenderer must complete the following schedule comprehensively, indicating the names of Manufacturers and/or suppliers and unit types and must submit Technical brochures for the equipment he proposes to supply for the work.
ITEM MANUFACTURE & MODEL Nos.
1. Sanitary Appliances ……………………………………………………
1. Stainless steel sinks …………………………………………………….
1. Wash Hand Basins ……………………………………………………..
1. Taps …………………………………………………………………….
1. Galvanised Mild Steel pipes and fittings ………………………………………………………………………...
1. u.P.V.C pipes and fittings (drainage) ………………………………………………………………………….
1. u.P.V.C pressure pipes and fittings …………………………………………………………………………….
1. Valves ………………………………………………………………….
1. Water Tanks ……………………………………………………………..
1. Portable firefighting units ……………………………..………………..
1. Hose Reels …………………………………………………………….
Signature: ……………..…….. Date: ……………………… 20 …………. Tenderer
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PLUMBING INSTALLATION
WATER PIPES TESTING REPORT
Project………………………………… Date …………….. 20……..
Foreman/Plumber …………………………………………………….
DATA RECORDED ON SITE
Location and Ref. Drawing:
Length/Diameter of Pipe:
Class/Type of pipe
Test Pressure Required
Water filled at –
Test Pressure Reached at –
Loss of Water/Pressure – Reading
1st Hr. 2nd Hr. 3rd Hr. 4th Hr. 6th Hr.
Quantity of water pumped to Retain test pressure:
Allowable Quantity of Leakage
Remarks
Signature: ……………………. Date: …………………… 20 ………………... (C.O.W/R.E)
Signature: …………………………. Date: ……………… 20 ………………... Foreman/Plumber
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FIRE FIGHTING/PROTECTION INSTALLATION
PORTABLE FIRE EXTINGUISHERS The Contractor shall supply and install portable fire extinguishers as shown on the Contract Drawings and as directed on site by the Engineer. These shall be containing an extinguishing medium of water, foam powder, carbon dioxide or halon, contained in a metal body, rechargeable or non- rechargeable. The units shall comply in all respects to B.S. 5423:1980 and B.S. 5306 Part 3, 1985.
Where fixed on the wall, an appropriate fixing method shall be used, with rawl plugs in the wall to ensure permanent fix.
Timber pegs shall not be acceptable for wall fixing. The units shall be supplied sealed to manufacturer’s recommendation and the seal shall be easily breakable to facilitate quick use during fire fighting operation.
HOSE-REEL INSTALLATION The Contractor shall supply and install the hose-reel fire fighting installation all as shown on the Contract Drawings and as directed by the Engineer.
The hose reels shall comply in all respects to B.S. 5274:1985; automatic type, with the reel-hose complying to B.S. 3169:1981.
Each hose-reel shall be fitted with a screw down globe valve to B.S. 1010, on the inlet to the reel.
The hose-reel booster pump shall be of centrifugal type, with a minimum capacity as shown on the drawings. The pump shall be complete with an electric motor, a pressure cylinder, a base plate together with a gate valve and a strainer on the suction side plus a non-return valve on the discharge side all as shown on the Contract Drawings. Control for the pump shall be by a pressure switch.
Piping for the hose-reel water supply shall be galvanised steel tubing to B.S 1387:1967, Class B with pipe threads to B.S. 21:1985. Pipe fittings shall
be seamless wrought steel to B.S. 1974 Part 1, 1971.
Gate valves shall be of bronze body and solid wedge with a non-rising stem and wheel, conforming to B.S. 5154:1983, and generally as Crane type DM 160. Check valves shall be Lift type with bronze body and composition disc conforming to B.S. 5154:1983 and generally as crane type DM 118.
All hose-reel supply pipework and fittings shall be painted etching primer and two coats of red enamel paint to comply to B.S. 1710:1984. All painting shall be applied to manufacturer’s instructions.
DRY-RISER INSTALLATION Pipes shall be galvanised steel tubing to B.S. 1387:1967 Class B with pipe threads to B.S. 21.
Pipe fittings shall be wrought steel seamless pipe fitting to B.S. 1740 Part 1: 1971.
Flanges: steel flanges to B.S. 4504:1969 PN 16. Fire Brigade Breeching inlet shall consist of twin inlets; each inlet consisting of 65mm diameter male instantaneous coupling to B.S. 336 with a non- return valve and a blank cap secured with a short chain.
The breeching inlet shall be enclosed in a sheet metal inlet box, finished in ‘fire red’ backed enamel paint, with wired glass door to B.S. 3980. The door shall be secured with spring lock such that it can only be opened from the inside by breaking the glass and releasing the catch on the lock.
The door glass front shall be clearly marked with 50mm high red lettering ‘DRY RISER BREECHING CONNECTOR’.
Landing valves shall be 65mm diameter gunmetal gate pattern dry riser outlets with flanged inlets and female instantaneous outlets fitted with plugs secured by short chain and conforming to B.S 5041: Part 2:1976.
Air Release Valve shall be fixed to the dry riser terminating at least one metre above the topmost landing valve.
The above valve shall be automatic air release valve conforming to B.S.
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1452.
The valve and the dry riser projecting over the roof shall be effectively earthed to prevent damage from lighting.
FIRE HYDRANTS The fire-hydrant system shall comply to the requirements of B.S. 5306 Part 1.
The fire hydrants shall be of the screwdown type to B.S. 750 type 2. These shall be of meehanite cast iron body with bronze spindle rings and nut and nickel-plated mild steel bearing plate.
Units shall have discharge capacity of not less than 34 1/s (450 gal/min) at a constant running pressure of 1.7 bars. Units shall be installed underground in a concrete block chamber with surface box manufactured from meehanite cast iron (medium or heavy traffic design as specified) all to B.S. 750. The cover shall be inscribed F.H and chained to the box, all as manufacturer by Glenfield Ltd., or equal, approved. An indication plate to B.S. 3251 and of approved manufacture shall be installed at a nearby and conspicuous position.
E. SPRINKLER SYSTEM
The specification shall comply with the Fire offices (FOC) rules for ordinary Hazard Group I. This is a wet pipe system that is permanently charged with water under pressure both above and below the installation alarm (wet pipe) valve.
PIPEWORK
1. All pipework above ground shall be heavy grade (class C) galvanized steel conforming to BS 1387 suitable for screwing to BS 21 pipe threads . 2. Pipes laid underground must conform to BS 3505 Unplasticised PVC pipe for cold water supply. 3. Joints must be made with fittings of the manipulative compression type
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to BS 864 part 2 only. Pipe bending is not allowed. 4. Allwelding of sprinkler pipework must be carried out in accordance with the provisions of BS 2640, BS 2971 or heating and ventilating contractors’ association manual-welding of mild steel pipework , except that the use of “set in type branches or sockets” and “cut and shut” or “segmented” bends is not permitted. 5. All pipework shall be given 2 coats of red paint.. 6. Slope of pipes for drainage: Sprinkler pipes of installations , whether on the wet , dry or alternate system must be installed such that the system can be thoroughly drained. Sprinkler pipes must be laid to the following minimum slopes:
Wet pipe systems -2mm in 1 m
Dry pipe and alternate wet and dry pipe systems with pipe diameter
50mm and above -4mm in 1 m
Dry pipe and alternate wet and dry pipe systems with pipe diameter
less than 50mm – 12mm in 1 m.
7. Support of pipework: The contractor shall make use of the following items to support the pipework as necessary:
Hangers
Fasteners
Primary support brackets
Pipe clips
Sling rods
U – bolts and
toggles 8. Spacing and location of hangers: There must be at least one hanger for each pipe section : the distance between hangers for horizontal and vertical sprinkler pipework shall not exceed the following: Nominal diameter of pipe(mm) maximum spacing(m) Less or equal to 65 4.0
More than 65 and upto 100 6.1
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More than 100 and upto 250 6.5
PRESSURE GAUGES 1. On all installations, there must be a pressure gauge (c ) fitted
immediately above the alarm valve and another (b ) immediately below the alarm and main stop valves.
2. Pressure gauges shall conform to BS 1780. The maximum scale value of such gauges should be of the order of 150 per cent of the known maximum pressure. Pressure gauges must have divisions not exceeding 0.2 bar for a maximum scale value of 10bar, not exceeding 0.5 bar for a maximum scale of 16 bar and not exceeding 1 bar for a maximum scale exceeding 16 bar.
3. Means must be provided to enable each pressure gauge to be readily removed without interruption of installation water supplies.
FITTINGS
VALVES Installation control valves: The installation must be provided with a set of installation control valves comprising:
a main stop valve
an alarm valve suitable for a wet system and
a water motor alarm and gong.
STOP VALVES:
1. All stop valves must be right handed i.e they must be so constructed that in order to shut the valve , the spindle must turn clockwise. The control wheels must be clearly marked showing in which direction the wheel is to be turned to close the valve. There must be an indicator also to show whether the valve is open or closed.
2. The following types of installation valves are allowed:
Gate / sluice valves designed and constructed to one or other of the following specifications or equal and approved :
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BS 5150- cast iron wedge and double disc gate valves for general purposes
BS 5163- Double flanged cast iron wedge gate valves for water works purposes.
BS 1952-copper alloy gate valves for general purposes
BS 5157-steel gate valve for general purposes.
Gear operated butterfly valves designed and constructed in accordance with the following specifications or its equivalent subject to approval----BS 5155 cast iron and carbon steel butterfly valves for general purposes
BALL VALVES
Ball valves for use in connection with the incoming water main to be brass gun metal or other corrosion resistant material preferably equilibrium type to BS 1212 (1953) as GLENFIELD AND KENNEDY LTD.
All ball valves to be classified as high pressure Ball valves rated at 14.10 kg/sq. cm maximum.
CHECKVALVES to be of cast body incorporating flanges , for service of over 54 mm nominal bore to BS 5153 (1974). Services of 54 mm nominal bore and under to be copper alloy to BS 5154 (1974).
SPRINKLERS:
The sprinklers in this installation shall be 15mm conventional pattern suitable for pendent position and a temperature rating of 68 deg. C. PART B
GENERAL SPECIFICATION FOR ELECTRICAL WORKS
A. GENERAL CLAUSES
Regulations This specification covers the requirements of lighting and power installation in Kenya. All apparatus and material supplied and all work
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carried out shall comply with the Kenya Government Electrical Specifications, GES.1 and GES.2 and local Statutory Regulations. Installations should also be generally in accordance with the requirements of the 16th Edition of the "Regulations of the Electrical Equipment for Buildings" issued by the institution of Electrical Engineers, Which should be used as a “Code of practice" except where they conflict with Kenya Government Legislation regarding electrical installations.
Standards Except where otherwise indicated in this Specification the Contract Works and all manufactured items shall comply with the relevant Specification of the British Standards Installation. Such Specification are here in after referred to as "BS". In each case, the latest edition of such Specification shall apply. Should it be desired to offer equipment covered by other National or International Standards, the approval of the Engineer must be obtained, in Writing, before completion of the tender.
Records Drawings The contractor shall mark accurately on one set of drawings the conduit laid during the progress of the work. This information must be made available on site for inspection by the Engineer. At the completion of the Contract, the Contractor shall supply the engineer with one set of transparent originals, and two complete sets of prints showing the complete installation. The drawing shall include the location of all apparatus conduits and cable routes and a schematic diagram of the main distribution indicating the phasing of the system.
Contract Drawings These drawing form part of this specification and are to be read in conjunction with this specification to enable the contractor to prepare a tender. Where there are any omissions in the bills of quantities, contract drawings supersede the bills of quantities. These drawings are not intended to be used as working drawings unless they are released for that purpose.
Working Drawings
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The contractor shall prepare the working drawings as may be necessary. These shall be submitted to be Engineer for approval before the execution of the works.
Working drawings, to be prepared by the contractor, shall be detailed as below but not restricted only to these:-
1. General arrangement of drawings showing plants, M.V. Switchgear, distribution boards, consumer units, fittings, switches, switched sockets outlets etc.
2. Layout drawings of concealed and surface conduits, ducts, trucking etc.
3. Any other drawings that are not called for in the Specification. Two copies of all working drawings shall be submitted to the Engineer for approval. Thereafter, the contractor shall submit copies of approved working drawings for distribution to the parties concerned. The contractor shall not be relieved of any of this obligations under the contract or from correction any errors on site or elsewhere found subsequently in the approved working drawings by the Engineer.
Labels All switchgear, switch fuses, distribution boards, etc., shall be clearly labeled with black on white background engraved labels to indicate the name, purpose and position of the gear. All circuits in distribution boards shall be clearly identified in respect of the number and location of the M.C.B. The charts shall be securely fixed inside the covers of the distribution boards.
Galvanizing Galvanizing shall be applied by the hot process and shall consist of a smooth clean zinc coating free from defects and be uniform in thickness.
The thickness shall be not less than 610gms of zinc per square meter of surface and tested in accordance with the requirements of B.S 729 where applicable. Sheradiling or other alternative processes shall not
be used without approval in writing of the Engineer.
The preparation for galvanizing itself shall not adversely affect the mechanical properties of the coated material. Surfaces which are normally in contact with oil shall not be galvanized or cadmium plated. All out-door structures, access ladders, platforms, equipment cubicles shall be galvanized.
Cleaning and painting Having due regard to the destination and climate conditions under which the plant is to operate, extreme care shall be exercised in the manufacture of the equipment to prevent the formation of any corrosion. All equipment shall be cleaned of all dust, oil, grease, dirt, scale and rust by power tool operated metal brush or preferably by shot or grit blasting and then ground smooth where necessary. Unless otherwise approved, they shall then immediately have applied to them two coats of approved primer paint. After inspection any rough surface shall be filled in and smoothed over and further painting in the factory shall be as follows:-
(a) All interior of cubicles, kiosks, boxes etc., containing wiring or other apparatus and internal components of the plant which are dispatched to site in an assembled conditions, shall be finish painted with at least two coats of white enamel. The final oat shall be of white anti- condensation finish, where so specified.
(b) The external surface of the panels shall be finished in gray stove enamel to B.S. shade 631 or other shade as may be approved by the Engineer.
(c) All interior surface of tanks and other oil filled chambers and external surface of piping therein shall be painted finally with an oil resisting coating to the approved by the Engineer.
(d) All wall and floor mounted junction boxes, loose starters, etc., throughout the works shall be finished in grey stove enamel or painted finally with to B.S. 381C shade 631 or other shade as may be approved by the Engineer.
After all erection has been made completed at site, the contractor shall
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make good all defects in painting and galvanizing which have arisen during transport, storage and erection on site and shall apply undercoat and one finished coat of gloss paint to B.S. 311C shade as may be approved by the Engineer to the external surface of all equipment. Where galvanized metal work has been damaged it shall either be repaired by cold galvanizing at site or alternatively at the discretion of the Engineer, be returned to the manufacturer for re-galvanizing by the hot process.
Lighting and Distribution Boards
General lighting and power distribution boards shall comply with the B.S. 3817, 5861 and B.S. 214 and shall be of the metal clad pattern, flush mounted, except where otherwise specified on the drawings.
Construction Enclosures shall be substantially constructed from 16S.W.G. minimum thickness sheet steel having hinged front cover, and shall be vermin and insect proof. Each unit shall house M.C.B.’s and shall be supplied complete with bus-bars, earthing terminal, neutral bar, circuit chart, and blanking plate for any spare ways. The incoming isolator switch shall be integral with the distribution board in consumer Units only.
Miniature Circuit Breakers All distribution boards shall be supplied with M.C.B.'s manufactured to B.S. 3871 and of a rating as specified on the drawings. The circuit breakers shall incorporate both thermal overload and magnet short circuit tripping, with a trip-free mechanism.
Three phase circuits shall be controlled by integrally manufactured three pole circuit breakers, with one common operating lever. An intertripping mechanism shall ensure isolation of all three poles in the event of an overload or short circuit on any one phase.
Earth leakage Circuit Breakers If specified or indicated on the Contract drawings the use of E.L.C.B. for isolation of incoming supply in the distribution board shall be of an approved type for flush mounting. The general requirements of the
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E.L.C.B. are as follows:-
(a) It shall have high sensitivity i.e. it shall operate in 30 milliseconds for a leakage current of 30 milliampere.
(b) Its operation shall not rely on the mains supply for tripping under fault conditions. For example, in the event of a leakage from the live to earth conductor occurring at the same time as break in the neutral supply wire, the breaker shall trip.
Labeling A circuit chart in each board shall show the name, location and current loading of each circuit connected. Each board shall be fitted with an engraved identification label in black on white, such as "Distribution Board D.I.", etc, and all three phase distribution boards shall be labeled in white on red, "DANGER 415 VOLTS".
B.N N-METALLIC CONDUIT
Standards and Installation All non-metallic conduits shall be class `A' heavy gauge, high impact, PVC complying with BS 4606 part 2 type All. The minimum size to be used on the Contract is 20mm external diameter. The required sizes are shown on the Contract drawings. All conduit installation shall be concealed in the walls and floors or in structural slabs.
Joints Conduit will be joined and terminated utilizing the appropriate rigid PVC compounds as detailed below, or standard conduit entry electrical equipment. Jointing will conform to one of the following techniques:-
No. 1 - Permanent Adhesives - The solvent cement supplied by the conduit manufacturers will be used to produce a rigid sealed connection.
No. 2 - Flexible Adhesive - A non-hardening adhesive supplied by the conduit manufacturers will be used to produce a flexible sealed joint where allowance is necessary for longitudinal movement (e.g.
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expansion couplers).
Bends Bends and sets in the conduit will be made in accordance with the manufacturer’s instructions. The radius of the bend shall not be less than 2.5 times the outside diameter of the conduit or such greater radius which will facilitate easy drawing in of cables.
Expansion Adequate allowance shall be made for longitudinal expansion and contraction of the conduit under normal working temperature variations as follows:-
(a) Expansion couplers should be used in straight runs exceeding 6 meters with a loose or flexible type joint N0.2 above) at the long spout end of the coupler.
(b) Saddles as supplied by the manufacturers shall include a sliding support tolerance for longitudinal expansion.
Special consideration may need to be given to the fixing of accessories where this may prevent natural conduit movements. Over size or slotted fixing holes may be necessary or the introduction of expansion couplers.
Support Conduits should be supported by saddles, at not more than 900mm intervals. Where working temperatures tend to be high this should be reduced to 600mm.
Conduit Boxes and Fittings (a) All conduit boxes shall be circular or square pattern of Rigid PVC suitable for plain connections conforming to sheet 62 B.S. 4607 part 2. Boxes for supporting a fitting or accessory shall be fitted with a PVC lid held in position by means of two 2BA round headed screws Boxes shall have metallic screwed inserts.
(b) Circular or square boxes shall be provided at all outlet points, unless otherwise specified and lighting fitting, ceiling switches
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and other accessories will be screwed to the internal lugs of the boxes. Care must be taken when considering the use of totally enclosed fitting with PVC circular boxes where the temperature within the box is likely to rise above 60 C [140 F]. Special steel insert clips should be used in conjunction with circular boxes where heavy pendants are used.
(c) Looping in boxes of circular P.V.C. pattern to sheet 63B.S. 4607 part 2 may be used in such work as dictated by the structure of the buildings. Conduit entry shall be made by means of P.V.C. bushes.
(d) Adaptable boxes shall be of molded or fabricated PVC of square or oblong shape complete with P.V.C. Lids secured by 2 BA or steel plates round-headed screws. All adaptable boxes and lids of the same size shall be interchangeable. No adaptable box smaller than 75mm x 50mm or larger than 300mm x 300mm shall be employed. Boxes shall be of adequate depth in relation to the size of conduit entering them.
(e) Conduits shall be terminated at adaptable boxes, fuse-board switches, sockets outlets or other equipment not possessing push-in or threaded spouts, by means of appropriate size female adapter and PVC hexagonal headed Bare Bush. All cemented joints to be made to a depth of not less than the diameter of the conduit being used.
Earth Continuity Earth continuity shall be provided by a separate insulated conductor drawn into the plastic conduit and rated in accordance with circuit loadings and appropriate regulations, or as mentioned, on the drawings.
Where required under the Regulations, an earth continuity conductor shall be provided for lighting fittings in which case the control switches shall be equipped with an appropriate earth terminal.
Arrangement of Conduit Layout The conduit system shall be carefully planned and erected to avoid
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unnecessary bends or changes in direction. Conduits shall be laid in straight horizontal or vertical lines with easy sets. Where several conduits follow similar routes, they shall be laid out from a common center. Where draw-in boxes for right angled change of direction are required in multiple runs, adaptable boxes shall be used for such size as to allow conduits to enter the box without sets. Where conduits are concealed or laid on constructional floors, they shall be secured by fixing as approved by the Engineer. Where it is essential that conduits cross one another in floors, the chases shall be deepened and the conduits set to create the minimum desirable diversion.
Care shall be taken to ensure that there are no obstructions to cables within the conduits caused by the ingress of plaster, concrete, or other matter. Conduit ends must be square and cleaned of burrs.
Conduit Draw-in Points Conduits for each circuit shall be completely erected before any cable is drawn in. Adequate draw-in points shall be provided. Straight runs shall have draw-in facilities at distance not exceeding 12 meters. Runs incorporating sets of bends shall have draw-in facilities at a distance not exceeding 9 meters. These distances may need to the reduced in difficult situations or with particular cable complexes.
Not more than four easy sets, or two right angle bends or sets may be installed between draw-in points. Solid elbows or tees shall not be accepted.
C. FINAL CIRCUIT WIRING
Type All power and lighting wiring cables shall be 600/1000 volt grade, single core, P.V.C. insulated, with stranded copper conductors, manufactured in accordance with B.S. 6006. The minimum size of lighting circuits shall be 1.5 sq.mm sizes, 4.0sq.mm on power spur circuits and 2.5sq.mm on ring main circuits.
Installation Cables forming circuits connected to different distribution boards shall not be drawn into the same conduit or draw-in box. The cables shall
be coloured in accordance with Table B4 of the IEE Regulations. Cables used on extra low voltage circuits shall be of distinctive colours other than these colours. No reduction of the strands forming the conductors shall be allowed at switch or other terminals, but all strands shall be effectively secured by screws, nuts and washers or other approved means.
Cables shall be joined together at the terminals of ceiling boxes and other accessories. Under no circumstances will joints be permitted in the run of the cable.
D. P.V.C. INSULATED ARMOURED CABLES
Type These shall be 600/1000 voltage grade to BS.6346 or B.S 6004 having copper wire insulated, P.V.C. sheathed, single wire armoured and P.V.C. sheathed overall. The cores of four core cables shall be distinctively coloured red, yellow, blue and black. The Contractor shall provide suitable glands and accessories for all armoured cable termination, and where cables are suspended shall provide the necessary rack, cleat or hanger supports and fixing.
Cable supports and racks shall be made by a recognised manufacturer and shall be to the approval of the Consulting Engineer.
All supports and racks shall be arranged as far as is practicable for the easy removal of any single cable in a multi-cable run, without threading cables through supports and racks. The number of types of supports and racks shall be kept to a minimum commensurate with meeting the requirements of the Contract Works.
Laying of Cables The work of excavating and back-filling of all trenches for cables, is included in this contract and the responsibility for positioning, width and depth of trenches, and for laying and bedding of all cables and protective covers is included with the Electrical Works covered by this Specification. Cables shall be laid in trenches at the following minimum depths.
For M.V. cables in open ground 0.55m
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For M.V. cables under roads and pavements 0.85
Where more than one cable is laid in a trench, cables shall be spaced as follows:
Between M.V. cables 0.1m Between M.V. and telephone cables 0.4m Between M.V. and L.V. cables 0.4m Between L.V. and telephone cables 0.4m Between L.V. cables 0.1m
In straight run trenches cable crossings shall not be permitted except where cables branch from the main run. At every draw-in point or junction box the cable should be snaked.
Before cables are laid the bottom of the trench shall be evenly graded and cleared of all loose stones, and shall then be covered with an 80mm layer of sand or sifted soil and lightly compacted, and a further 80mm layer shall be placed on top of the cables. The approved cable protection, see Clause 2.27, shall then be laid and the excavated materials in 0.2m layers, each layer being well compacted by hand or mechanical punners before the next layer is filled.
The width of the trench shall be such that a clearance of 80mm shall be provided between outermost cable and the side of the trench. Where cables are disposed in more than one layer, the vertical spacing shall be 0.4. between centres of cables or cable groups, the depth of the trench being made suitable accordingly.
Protective Covers The protective covers, of approved local manufacture to BS.2484 shall be provided over cables laid in the ground each complete with an interlocking device to prevent lateral displacement. These protective covers shall extend at least 50mm laterally beyond the outside of the outer cable in each group of cables so protected.
Cable Position Markers These should be placed adjacent to all points where cables change
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direction, and at all intervals of not more than 30m and at other positions designated by the Architect or the Consulting Engineer.
Sealing of Cable Entries Where cables enter a building in pipes, or ducts, the mouths of the pipes or ducts shall be effectively sealed by means of close fitting solid impregnated wooden plugs and mixture of compound and transformer oil, or other approved manner.
All cables passing through interior walls or floors shall be effectively sealed to the approval of the Engineer By means of asbestos cement after the cables have been pulled through, in order to prevent the accumulation of moisture and the ingress of debris, sand or vermin. The cost of sealing the cables shall be included in the rates for erection and laying.
Protection Against Mechanical Damage All cables located in such positions where they are vulnerable to damage by mechanical or other means shall be protected by suitable lengths of steel pipe bushed to prevent damage to the cable.
2.31. Rating Plates Each cable when completely erected shall have permanently attached to it at each end, and in such intermediate positions as may be considered necessary by the Engineer, metal plates upon which is engraved, or stamped, the identification number of cable together with it supplies. This information shall be recorded by the contractor so that it may appear on drawings of the completed installation.
Cable Jointing The Contractor shall be wholly responsible for sealing and jointing of all cables supplies and erected under the contract. The cable boxes, loop-boxes and glands for power and L.V. cables on all items of equipment shall be provided under the contract.
Sealing and jointing shall be in accordance with the best current practices and of first class workmanship. Where cable armouring is used as earth continuity conductors the glands shall have the necessary contact surfaces or straps to provide a low resistance path
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under fault conditions. The Tender shall include for all cable jointing where appropriate and also all labour, jointing material and compound, together with the use of all jointer`s tools and making of the tails to the apparatus terminals. Generally, cable terminations on switchgear, transformers, joint boxes, outgoing, and incoming circuits on the switch-boars shall be glanded in an approved manner.
E. SOCKET OUTLETS
General In all areas, general power outlets shall be of the 13 Amp.3 pin fused plug type complying with BS. 1363. They shall be flush pattern with white or ivory plates unless otherwise specified on the drawings. Where the circuits are supplied from a common feed, two outlets shall form a twin unit in a common box. The earthing terminal of every socket outlet shall be connected to the earth continuity conductor of the final circuit by an appropriately sized insulated copper conductor. Unless otherwise stated they shall be mounted at 300mm above finished floor level.
Plugs One fused plug top shall be supplied for each socket outlet installed. Fuses shall be 13 Amp unless otherwise specified.
A. FUSED CONNECTION UNITS
General All fused connection units shall be 13 Amp. with fuse and neon indicator lamp. Boxes shall be flush type with white or ivory copper plates and shall be switched type unless otherwise specified on the drawings.
Fuses All fused connection units shall be fitted with 13 Amp. Fuses, unless otherwise specified.
Labeling
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The front plate of each fused connection unit shall, unless otherwise specified, be engraved with the name of the appliance connected to it.
G. LIGHTING SWITCHES
Type Lighting switches shall be of the all insulated rocker operating plate switch type to BS. 3676 of ample rating. Switch inserts shall be white set in white or ivory cover plates.
Switches controlling points in bathrooms shall be placed outside the bathroom or consist of a ceiling switch operated by a non-conducting cord, as specified. Switches mounted outdoors shall be of a weather tight pattern.
Switches shall be one way, two ways or intermediate as specified and where a number of switches are mounted together they shall be tilted in a common box.
Ceiling switches shall be white or ivory semi recessed pattern, and shall only be used where specified. Pull cords shall be fitted with shock absorbing springs.
H. LIGHTING FITTINGS
General The Contractor shall supply and fit all lighting fittings of the type indicated on the drawings and in the schedules. All fittings shall be suitable for operation on a 240V, 50Hz supply. Lighting fittings rated other than 240 volts will not be accepted. All lighting fittings shall be supplied with lamps.
Fluorescent Fittings. Fluorescent fittings shall generally be of the batten type, with control gear contained within the supporting channel. All fittings shall be supported from conduit boxes, and shall be suspended by two 20mm diameter conduits to give a clearance of 25mm between the top of the fitting and the ceiling. Where fittings are suspended by chains from the ceiling the contractor shall use white flexible cord between the box and
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the fittings.
The installation of the suspension chain and cord shall be approved on site by the Engineer. In the ceiling, conduit boxes, to BS. 31, shall be fitted with dome covers, to which the suspension conduits shall be joined, so that the lighting fitting hangs vertically below the conduit boxes.
Fitting shall comply with BS. 3820 or class1, indoor normal atmospheres.
All fluorescent fittings shall be fitted with radio interference suppression capacitors and power factor correction capacitors and shall be earthen.
Reflectors and Diffusers All reflectors for fluorescent fittings shall be made of sheet metal suitably shaped and stiffened, and shall be of white enamel finish. The diffusers shall be of white enamel finish. The diffusers shall be of white opal type in extruded plastic with external reeding.
Lamps All lighting fittings shall be supplied complete with lamps of the type and rating specified. Fluorescent tubes shall be of the "white" type, except where otherwise stated. Pearly type tungsten lamps will be fitted in open fittings.
FLEXIBLE CORDS
General These shall be of 250 volt grade PVC insulated and shall comply with BS.7. Flexible cords shall not be less than 24/.20(23/.0076).
Flexible cords for pendant fittings shall be circular type, heat resistant and white in coluor.
J. EARTHING
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Earthing Electrodes Earth electrodes shall be minimum 1.4 meters long by 12mm diameter hard drawn copper rod, and shall be located not less than 3 meters apart at a convenient position 6 meters away from the building. The terminal head of each electrode shall be in a concrete inspection pit, with cover. If the resistance to earth is not satisfactory with one electrode, then additional electrodes or an earth mat shall be provided as directed by the Engineer.
Distribution System Earthing All distribution boards shall be earthed in accordance with the I.E.E. Regulations. All metal work associated with the regulations currently in force.
Testing of Earthing System The resistance of the earth continuity system when measured between earthing point and other point in the installation, including all conduit and metal work which may provide a path or earth, shall not exceed 0.5 ohm where steel conduit forms part or the whole part of the system, or 1.0 ohm, if the earth continuity system is composed entirely of copper, copper alloy or aluminium. When the installation is complete the Contractor shall carry out tests for earth loop impedance, polarity insulation resistance, ring circuit continuity and earth electrode resistance, in the presence of, and to the satisfaction of the Engineer and the K.P.& L.C. The Contractor shall rectify all work not giving test results within the limits prescribed.
P.M.E. system Provision shall be made for P.M.E. System at supply intake (where applicable) and on the isolators of the adjacent building. "P.M.E." means that system whereby the neutral conductor of the supply network is earthed at a prescribed number of points along its route, together with the installation earth continuity conductor, at each consumer's installation, so providing a metallic path for the flow of earth fault currents. The connections between the neutral conductor of the installation shall be made by the supply. Authority at the point of intake only. The connection at the isolators will be made by the Contractor in the presence of the Engineer after completion of all tests.
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COMMISSIONING
All installations shall be tested to the statutory requirements of the Electricity Authority, and commissioned in the presence of and to the satisfaction of the Engineer.
Four copies of tests reports shall be provided within seven days of carrying out the tests; and reports shall include full details of how each test was carried out, and a copy of all readings taken.
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SECTION VII: BILL OF QUANTITIES
TENDER AMOUNT:
Kenya shillings……………………………………………………………
………………………………………………………………………………
………………………………………………………………………………
TENDERER SIGNATURE…………………………………DATE…………………
NAME / ADRESS …………………………………… …...………………………………… …………………………………… ……………………………………
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SECTION VIII – STANDARD FORMS
.
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FORM OF INVITATION FOR TENDERS
[date]
To: [name of Contractor] [address]
Dear Sirs:
Reference: [Contr act Name]
You have been prequalified to tender for the above project.
We hereby invite you and other prequalified tenderers to submit a tender for the execution and completion of the above Contract.
A complete set of tender documents may be purchased by you from
[mailing address, cable/telex/facsimile numbers].
Upon payment of a non-refundable fee of Kshs
All tenders must be accompanied by number of copies of the same and a security in the form and amount specified in the tendering documents, and must be delivered to
[address and location]
at or before (time and date). Tenders will be opened immediately thereafter, in the presence of tenderers’ representatives who choose to attend.
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Please confirm receipt of this letter immediately in writing by cable/facsimile or telex.
Yours faithfully,
Authorised Signature
Name and Title
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TO:
FORM OF TENDER [Name of Employer)
[Date] [Name of Contract]
Dear Sir,
1. In accordance with the Conditions of Contract, Specifications, Drawings and Bills of Quantities for the execution of the above named Works, we, the undersigned offer to construct, install and complete such Works and remedy any defects therein for the sum of Kshs. [Amount in figures]Kenya Shillings [Amount in words]
2. We undertake, if our tender is accepted, to commence the Works as soon as is reasonably possible after the receipt of the Project Manager’s notice to commence, and to complete the whole of the Works comprised in the Contract within the time stated in the Appendix to Conditions of Contract.
3. We agree to abide by this tender until [Insert date], and it shall remain binding upon us and may be accepted at any time before that date.
4. Unless and until a formal Agreement is prepared and executed this tender together with your written acceptance thereof, shall constitute a binding Contract between us.
5. We understand that you are not bound to accept the lowest or any tender you may receive.
Dated this 20
day of
Signature in the capacity
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of duly authorized to sign tenders for and on behalf of
[Name of Employer] of [Address of Employer]
Witness; Name
Address
Signature
Date
.
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Bidders must provide information on any history of litigation or arbitration resulting from contracts executed in the last five years or currently under execution.
Year Award for or against
Name of client, cause of litigation and matter in dispute
Disputed amount (current value, Kshs. equivalent
2019
2018
2017
2016
2015
2014
Signature & Stamp………………………
Date……………......................................
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INTEGRITY DECLARATION UNDERTAKING BY TENDERER ON ANTI – BRIBERY POLICY / CODE OF CONDUCT AND COMPLIANCE PROGRAMME 1. Each Tenderer must submit a statement, as part of the Tender documents, in
either of the two given formats which must be signed personally by the Chief Executive Officer or other appropriate Senior Corporate Officer of the Tendering company and, where relevant, of its subsidiary in the Kenya. If a Tender is submitted by a subsidiary, a statement to this effect will also be required of the parent company, signed by its Chief Executive Officer or other appropriate Senior Corporate Officer.
2. Tenderers will also be required to submit similar No-bribery commitments from
their subcontractors and consortium partners; the Tenderer may cover the subcontractors and consortium partners in its own statement, provided the Tenderer assumes full responsibility. a) Payment to agents and other third parties shall be limited to appropriate
compensation for legitimate services. 1
b) Each Tenderer will make full disclosure in the Tender documentation of the beneficiaries and amounts of all payments made, or intended to be made, to agents or other third parties (including political parties or electoral candidates) relating to the Tender and, if successful, the implementation of the contract.
c) The successful Tenderer will also make full disclosure [quarterly or semi-
annually] of all payments to agents and other third parties during the execution of the contract.
d) Within six months of the completion of the performance of the contract, the
successful Tenderer will formally certify that no bribes or other illicit commissions have been paid. The final accounting shall include brief details of the goods and services provided that they are sufficient to establish the legitimacy of the payments made.
e) Statements required according to subparagraphs (b) and (d) of this
paragraph will have to be certified by the company's Chief Executive Officer, or other appropriate senior corporate officer.
3. Tenders which do not conform to these requirements shall not be considered.
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4. If the successful Tenderer fails to comply with its No-bribery commitment,
significant sanctions will apply. The sanctions may include all or any of the following:
a) Cancellation of the contract;
b) Liability for damages to the public authority and/or the unsuccessful
competitors in the Tendering possibly in the form of a lump sum representing a pre-set percentage of the contract value (liquidated).
5. Tenderers shall make available, as part of their Tender, copies of their anti-
Bribery Policy/Code of Conduct, if any, and of their-general or project - specific - Compliance Program.
6. The Government of Kenya has made special arrangements for adequate oversight of the procurement process and the execution of the contract, and has invited civil society and other competent Government Departments to participate in the oversight. Those charged with the oversight responsibility will have full access to all documentation submitted by Tenderers for this contract, and to which in turn all Tenderers and other parties involved or affected by the project shall have full access (provided, however, that no proprietary information concerning a Tenderer may be disclosed to another Tenderer or to the public).
FORM 10 ANTI-CORRUPTION DECLARATION COMMITMENT/ PLEDGE (Sections 62 of the PPAD Act, 2015)
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I/We/Messrs………………………………………………………………………. of Street, Building, P O Box…………………………………………………. …………………………………………………………………………………. Contact/Phone/E mail………………………………………………………… Declare that Public Procurement is based on a free and fair competitive Tendering process which should not be open to abuse. I/We..………………………………………………………………………… Declare that I/We will not offer or facilitate, directly or indirectly, any inducement or reward to any public officer, their relations or business associates, in connection with Tender/Tender No ………………………..……………………………….. for or in the subsequent performance of the contract if I/We am/are successful. Authorized ...................................................Signature.............................. Name and Title of Signatory………………………………………………….
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FORM 11 SITE VIEWING CERTIFICATE
PROPOSED REHABILITATION OF THE NAIROBI COMMUTER RAIL ADMINISTRATIVE OFFICES AT KENYA RAILWAYS, HEADQUARTERS TENDER NO.KR/SCM/107/2019-2020 The tenderer shall view the site under the guidance of KR personnel. _________________________________________________________
I hereby certify that I have viewed all the sites as required under the schedule of requirements. Tender No: KR/SCM/107/2019-2020 Bidders will indicate that they have viewed the site and have the representative sign certificate. (a) KR REPRESENTATIVE DESIGNATED OFFICER NAME ……………………………………………. SIGN……………………………….DATE………………STAMP……………………
b) TENDERERS REPRESENTATIVE
TENDERERS NAME…………………………………………………………… SIGN…………………….…..DATE……………………STAMP ……………….…
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LETTER OF ACCEPTANCE [letterhead paper of the Employer]
[date]
To: [name of the Contractor]
[address of the Contractor]
Dear Sir,
This is to notify you that your Tender dated
for the execution of
[name of the Contract and identification number,as given in the Tender documents] for the Contract Price of Kshs.
[amount in figures][Kenya Shillings (amount in words) ] in accordance with the Instructions to Tenderers is hereby accepted.
You are hereby instructed to proceed with the execution of the said Works in accordance with the Contract documents.
Authorized Signature …………………………………………………………………
Name and Title of Signatory …………………………………………………………
Attachment : Agreement
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FORM OF AGREEMENT
THIS AGREEMENT, made the day of 20
between of[or whose registered office is situated at] (hereinafter called “the Employer”) of the one part AND of[or whose registered office is situated at] (hereinafter called “the Contractor”) of the other part.
WHEREAS THE Employer is desirous that the Contractor executes
(name and identification number of Contract ) (hereinafter called “the Works”) located at [Place/location of the Works]and the Employer has accepted the tender submitted by the Contractor for the execution and completion of such Works and the remedying of any defects therein for the Contract Price of Kshs [Amount in figures],Kenya Shillings [Amount in words].
NOW THIS AGREEMENT WITNESSETH as follows:
1. In this Agreement, words and expressions shall have the same meanings as are respectively assigned to them in the Conditions of Contract hereinafter referred to.
2. The following documents shall be deemed to form and shall be read and construed as part of this Agreement i.e.
(i) Letter of Acceptance
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(ii) Form of Tender
(iii) Conditions of Contract Part I
(iv) Conditions of Contract Part II and Appendix to Conditions of Contract
(v) Specifications
(vi) Drawings
(vii) Priced Bills of Quantities
3. In consideration of the payments to be made by the Employer to the Contractor as hereinafter mentioned, the Contractor hereby
covenants with the Employer to execute and complete the Works and remedy any defects therein in conformity in all respects with the provisions of the Contract.
4. The Employer hereby covenants to pay the Contractor in consideration of the execution and completion of the Works and the remedying of defects therein, the Contract Price or such other sum as may become payable under the provisions of the Contract at the times and in the manner prescribed by the Contract.
IN WITNESS whereof the parties thereto have caused this Agreement to be executed the day and year first before written.
The common Seal of
Was hereunto affixed in the presence of
Signed Sealed, and Delivered by the said
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Binding Signature of Employer
Binding Signature of Contractor
In the presence of (i) Name
Address
Signature
[ii] Name
Address
Signature
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FORM OF TENDER SECURITY
WHEREAS ………………………………………..(hereinafter
called
“the
construction ……………………………………………………………………… …………………… (name of Contract)
of
Tenderer”) has submitted his tender dated ………………………… for the
KNOW ALL PEOPLE by these presents that WE ……………………… having our registered office at ………………(hereinafter called “the Bank”), are bound unto ……………………………(hereinafter called “the Employer”) in the sum of Kshs.……………………… for which payment well and truly to be made to the said Employer, the Bank binds itself, its successors and assigns by these presents sealed with the Common Seal of the said Bank this ……………. Day of ………20…………
THE CONDITIONS of this obligation are:
1. If after tender opening the tenderer withdraws his tender during the period of tender validity specified in the instructions to tenderers Or
2. If the tenderer, having been notified of the acceptance of his tender by the Employer during the period of tender validity:
(a) fails or refuses to execute the form of Agreement in accordance with the Instructions to Tenderers, if required; or
(b) fails or refuses to furnish the Performance Security, in accordance with the Instructions to Tenderers;
We undertake to pay to the Employer up to the above amount upon receipt of his first written demand, without the Employer having to substantiate his demand, provided that in his demand the Employer will note that the amount claimed by him is due to him, owing to the occurrence of one or both of the two conditions, specifying the occurred condition or conditions.
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This guarantee will remain in force up to and including thirty (30) days after the period of tender validity, and any demand in respect thereof should reach the Bank not later than the said date.
[date[ [signature of the Bank]
[witness] [seal]
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PERFORMANCE BANK GUARANTEE
To: (Name of Employer) (Date)
(Address of Employer)
Dear Sir,
WHEREAS (hereinafter called “the Contractor”) has undertaken, in pursuance of Contract No. dated
to execute (hereinafter called “the Works”);
AND WHEREAS it has been stipulated by you in the said Contract that the Contractor shall furnish you with a Bank Guarantee by a recognised bank for the sum specified therein as security for compliance with his obligations in accordance with the Contract;
AND WHEREAS we have agreed to give the Contractor such a Bank Guarantee:
NOW THEREFORE we hereby affirm that we are the Guarantor and responsible to you, on behalf of the Contractor, up to a total of Kshs. (amount of Guarantee in figures) Kenya Shillings (amount of
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Guarantee in words), and we undertake to pay you, upon your first written demand and without cavil or argument, any sum or sums within the limits of Kenya Shillings (amount of Guarantee in
words) as aforesaid without your needing to prove or to show grounds or reasons for your demand for the sum specified therein.
We hereby waive the necessity of your demanding the said debt from the Contractor before presenting us with the demand.
We further agree that no change, addition or other modification of the terms of the Contract or of the Works to be performed thereunder or of any of the Contract documents which may be made between you and the Contractor shall in any way release us from any liability under this Guarantee, and we hereby waive notice of any change, addition, or modification.
This guarantee shall be valid until the date of issue of the Certificate of Completion.
SIGNATURE AND SEAL OF THE GUARANTOR
Name of Bank
Address
Date
246
BANK GUARANTEE FOR ADVANCE PAYMENT
To: [name of Employer] (Date) [address of Employer]
Gentlemen,
Ref: [name of Contract]
In accordance with the provisions of the Conditions of Contract of the above-mentioned Contract, We, [name and Address of Contractor] (hereinafter called “the Contractor”) shall deposit with [name of Employer] a bank guarantee to guarantee his proper and faithful performance under the said Contract in an amount of Kshs. [amount of Guarantee in figurers] Kenya Shillings [amount of Guarantee in words].
We, [bank or financial institution], as instructed by the Contractor, agree unconditionally and irrevocably to guarantee as primary obligator and not as Surety merely, the payment to [name of Employer] on his first demand without whatsoever right of objection on our part and without his first claim to the Contractor, in the amount not exceeding Kshs [amount of Guarantee in figures] Kenya Shillings
_[amount of Guarantee in words], such amount to be reduced periodically by the amounts recovered by you from the proceeds of the Contract.
We further agree that no change or addition to or other modification of the terms of the Contract or of the Works to be performed thereunder or of any of the Contract documents which may be made between [name of Employer] and the Contractor, shall
247
in any way release us from any liability under this guarantee, and we hereby waive notice of any such change, addition or modification.
No drawing may be made by you under this guarantee until we have received notice in writing from you that an advance payment of the amount listed above has been paid to the Contractor pursuant to the Contract.
This guarantee shall remain valid and in full effect from the date of the advance payment under the Contract until (name of Employer) receives full payment of the same amount from the Contract.
Yours faithfully,
Signature and Seal
Name of the Bank or financial institution
Address
Date
Witness:Name:
Address:
Signature:
Date:
248
QUALIFICATION INFORMATION
1. Individual Tenderers or Individual Members of Joint Ventures
1.1 Constitution or legal status of tenderer (attach copy or Incorporation Certificate); Place of registration:
Principal place of business
Power of attorney of signatory of tender
1.2 Total annual volume of construction work performed in the last five years
Year Volume
Currency Value
1.3 Work performed as Main Contractor on works of a similar nature and volume over the last five years. Also list details of work under way or committed, including expected completion date.
Project name Name of clientType of workValue of and contactperformed and Contract person year of completion
1.4 Major items of Contractor’s Equipment proposed for carrying out the Works. List all information requested below.
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Item of Equipment
Description, Make and age (years)
Condition(new , good, poor) and number available
Owned, leased (from whom?), or to be purchased (from whom?)
(etc.)
1.5 Qualifications and experience of key personnel proposed for administration and execution of the Contract. Attach biographical data.
Position Name Years of experience (general)
Years of experience in proposed position
Project Manager
(etc.)
1.6 Financial reports for the last five years: balance sheets, profit and loss statements, auditor’s reports, etc. List below and attach copies.
250
1.7 Evidence of access to financial resources to meet the qualification requirements: cash in hand, lines of credit, etc. List below and attach copies of supportive documents.
1.8 Name, address and telephone, telex and facsimile numbers of banks that may provide reference if contacted by the Employer.
1.9 Statement of compliance with the requirements of Clause 1.2 of the Instructions to Tenderers.
1.10 Proposed program (work method and schedule) for the whole of the Works.
2 Joint Ventures
2.4 The information listed in 1.1 – 1.10 above shall be provided for each partner of the joint venture.
2.5 The information required in 1.11 above shall be provided for the joint venture.
251
2.6 Attach the power of attorney of the signatory(ies) of the tender authorizing signature of the tender on behalf of the joint venture
2.7 Attach the Agreement among all partners of the joint venture ( and which is legally binding on all partners), which shows that:
a) all partners shall be jointly and severally liable for the execution of the Contract in accordance with the Contract terms;
b) one of the partners will be nominated as being in charge, authorized to incur liabilities and receive instructions for and on behalf of any and all partners of the joint venture; and
c) the execution of the entire Contract, including payment, shall be done exclusively with the partner in charge.
252
TENDER QUESTIONNAIRE
Please fill in block letters.
1. Full names of tenderer
………………………………………………………………………………
2. Full address of tenderer to which tender correspondence is to be sent (unless an agent has been appointed below)
………………………………………………………………………………
3. Telephone number (s) of tenderer
………………………………………………………………………………
4. Telex address of tenderer
………………………………………………………………………………
5. Name of tenderer’s representative to be contacted on matters of the tender during the tender period
………………………………………………………………………………
6. Details of tenderer’s nominated agent (if any) to receive tender notices. This is essential if the tenderer does not have his registered address in Kenya (name, address, telephone, telex)
………………………………………………………………………………
………………………………………………………………………………
Signature of Tenderer
Make copy and deliver to: (Name of Employer)
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CONFIDENTIAL BUSINESS QUESTIONNAIRE
You are requested to give the particulars indicated in Part 1 and either Part 2 (a), 2 (b) or 2 (c) and 2 (d) whichever applies to your type of business.
You are advised that it is a serious offence to give false information on this Form.
Part 1 – General
Business Name ………………………………………………………………………
Location of business premises; Country/Town……………………….
Plot No……………………………………… Street/Road …………………………
Postal Address……………………………… Tel No………………………………..
Nature of Business…………………………………………………………………..
Current Trade Licence No…………………… Expiring date…………………
Maximum value of business which you can handle at any time: K. pound………………………..
Name of your bankers………………………………………………………………
Branch……………………………………………………………………………… …
Part 2 (a) – Sole Proprietor
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Your name in full…………………………………… Age…………………………
Nationality………………………………… Country of Origin…………………
*Citizenship details …………………………………………………………………
Part 2 (b) – Partnership
Give details of partners as follows:
Name in full Nationality Citizenship Details Shares
1……………………………………………………………………………………
2……………………………………………………………………………………
3…………………………………………………………………………………… Part 2(c) – Registered Company:
Private or public……………………………………………………………
State the nominal and issued capital of the Company-
Nominal Kshs…………………………………………………………………
Issued Kshs……………………………………………………………………
Give details of all directors as follows:
Namein full. Nationality.Citizenship Details*.Shares.
1. ………………………………………………………………………………
255
2. ………………………………………………………………………………
3. ………………………………………………………………………………
4. ………………………………………………………………………………
Part 2(d) – Interest in the Firm:
Is there any person / persons in …………… ………(Name of Employer) who has interest in this firm? Yes/No………………………(Delete as necessary)
I certify that the information given above is correct.
………………………………………………………………… (Title) (Signature) (Date)
Attach proof of citizenship
STATEMENT OF FOREIGN CURRENCY REQUIREMENTS
(See Clause 23] of the Conditions of Contract)
In the event of our Tender for the execution of (name of Contract) being accepted, we would require in accordance with Clause 21 of the Conditions of Contract, which is attached hereto, the following percentage:
(Figures)………………………… (Words)…………………………………
of the Contract Sum, (Less Fluctuations) to be paid in foreign currency.
256
Currency in which foreign exchange element is required:
……………………………………………………………………………… ………
Date: The ………… Day of …………….. 20…………….
Enter 0% (zero percent) if no payment will be made in foreign currency.
Maximum foreign currency requirement shall be (percent) of the Contract Sum, less Fluctuations.
(Signature of Tenderer)
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DETAILS OF SUB-CONTRACTORS
If the Tenderer wishes to sublet any portions of the Works under any heading, he must give below details of the sub-contractors he intends to employ for each portion.
Failure to comply with this requirement may invalidate the tender.
(1)Portion of Works to be sublet:………………………………
[i) Full name of Sub-contractor and address of head office:……………………………… ………………………………
(ii) Sub-contractor’s experience of similar works carried out in the last 3 years with Contract value: ……………………………… ……………………………… ………………………………
(2)Portion of Works to sublet:………………………………
(i)Full name of sub-contractor and address of head office:………………………………
……………………………… ………………………………
(ii) Sub-contractor’s experience of similar works carried out in the last 3 years with contract value: ……………………………
[Signature of Tenderer) Date
258
LETTER OF NOTIFICATION OF AWARD
Address of Procuring Entity
To:
RE: Tender No.
Tender Name
This is to notify that the contract/s stated below under the above mentioned tender have been awarded to you.
1. Please acknowledge receipt of this letter of notification signifying your acceptance.
2. The contract/contracts shall be signed by the parties within 30 days of the date of this letter but not earlier than 14 days from the date of the letter.
3. You may contact the officer(s) whose particulars appear below on the subject matter of this letter of notification of award.
(FULL PARTICULARS)
SIGNED FOR ACCOUNTING OFFICER
259
FORM RB 1
REPUBLIC OF KENYA
PUBLIC PROCUREMENT ADMINISTRATIVE REVIEW BOARD
APPLICATION NO…………….OF……….….20……...
BETWEEN
…………………………………………….APPLICANT
AND
…………………………………RESPONDENT (Procuring Entity)
Request for review of the decision of the…………… (Name of the
Procuring Entity) of ……………dated the…day of ………….20……….in the
matter of Tender No………..…of …………..20…
REQUEST FOR REVIEW
I/We……………………………,the above named Applicant(s), of address:
Physical address…………….Fax No……Tel. No……..Email ……………,
hereby request the Public Procurement Administrative Review Board to
review the whole/part of the above mentioned decision on the following
grounds , namely:-
1.
2.
etc.
260
By this memorandum, the Applicant requests the Board for an order/orders
that: -
1.
2.
etc
SIGNED ……………….(Applicant)
Dated on…………….day of ……………/…20…
FOR OFFICIAL USE ONLY
Lodged with the Secretary Public Procurement Administrative Review
Board on ………… day of ………....20….………
SIGNED Board Secretary
261
SECTION XI: APPLICATION TO PUBLIC PROCUREMENT ADMINISTRATIVE REVIEW BOARD
262
FORM RB 1
REPUBLIC OF KENYA
PUBLIC PROCUREMENT ADMINISTRATIVE REVIEW BOARD
APPLICATION NO…………….OF……….….20……...
BETWEEN
…………………………………………….APPLICANT
AND
…………………………………RESPONDENT (Procuring Entity)
Request for review of the decision of the…………… (Name of the
Procuring Entity) of ……………dated the…day of ………….20……….in the
matter of Tender No………..…of …………..20…
REQUEST FOR REVIEW
I/We……………………………,the above named Applicant(s), of address:
Physical address…………….Fax No……Tel. No……..Email ……………,
hereby request the Public Procurement Administrative Review Board to
review the whole/part of the above mentioned decision on the following
grounds , namely:-
1.
2.
etc.
By this memorandum, the Applicant requests the Board for an order/orders
that: -
1.
2.
263
etc
SIGNED ……………….(Applicant)
Dated on…………….day of ……………/…20…
FOR OFFICIAL USE ONLY
Lodged with the Secretary Public Procurement Administrative Review
Board on ………… day of ………....20….………
SIGNED Board Secretary
PROPOSED REHABILITATION OF NAIROBI COMMYTER RAIL ADMINISTRATIVE
OFFICES AT KENYA RAILWAYS HEADQUARTERS
PRELIMINARIES
A Workmen compensation insurance Item 1
B insurance of works 1
C Allow for protection of other sections of the building and regular cleaning
Item 1
D Allow for removal of rubbish/debris/clean up of site after completion
Item 1
E Allow for payment of water bills for use in the works
Item 1
F
Allow for making good any affected section of the works including repainting any affected sections in the course of execution of work
Item 1
G Provide for site notice board and maintaining the same during construction
Item 1
TOTAL CARRIED TO GRAND SUMMARY
GROUND FLOOR ITEM DESCRIPTION UNIT QTY RATE AMOUNT
DEMOLITION AND REPAIRS
A
Take out existing painted blockboard partitions complete with timber framing complete with all doors and fitings 4000 mm overall height for the entire floor area SM
B
Carefully remove parquet floor finish and prepare surfaces to receive porcelain floor tiles (all C. A's office, Hollerith, records and other areas) SM
C
Remove existing rubber tiles along the corridors and prepare granito tiles floor finish ( corridor along Audit to SL's section) SM
D
Allow for polishing and cleaning of existing terrazzo floor finish along the corridors ( Native, Records, Hollerith and other areas) SM
E
Allow for wire brushing of existing external walls and columns to Project Manager's approval (entire wall and columns) SM
CEILING FINISHES
F Supply and fix 600 x 600 x 16 mm "Armstrong Fissured Minaboard" acoustic tiles fixed with metal suspended hangers as specified by manufacturers (Native, Records, Hollerith and other areas) SM
WALL FINISHES
PAINTING & DECORATING
G
Prepare and apply three coats silk vinyl emulsion paint to all walls internally. SM
H
Prepare and apply three coats silk vinyl emulsion paint ceiling surfaces (along corridors and native area) SM
I
Prepare and apply three coats silk vinyl emulsion paint to corridor walls and columns including external walls SM
J Prepare surfaces and apply clear varnish to frames and door surfaces SM
K
Prepare surface and apply gloss paint to casement window, staircase railings. SM
Carried to Collection
ITEM DESCRIPTION UNIT QTY RATE AMOUNT
FLOOR FINISHES -
Cement and sand 1:4 screeds -
A 30mm thick screed steel trowelled smooth SM
-
-
B
Supply and fix approved colour high quality porcelain tiles as “SAJ” or other equal and approved fixed with and including cement mortar and grouting joints with approved epoxy resin-based grout (all C. A's office, Hollerith, records and other areas) SM
-
C To skirting. LM -
-
D
Supply and fix approved colour high quality polished granito tiles as “SAJ” or other equal and approved fixed with and including cement mortar and grouting joints with approved epoxy resin-based grout ( corridor along Audit to SL's section) SM
-
-
E To Skirting LM -
DOORS
IRONMONGERY
F
Supply and fix 3 lever mortice lock or approved equivalent complete with furniture. NO
-
G Ditto rubber door stops NO -
H
Allow for any required repairs to the door leafs to make good previous door locks locations. Item
Doors, frames and finishings in wrought Mahogany
I Quandrant 25 x 25mm LM -
J Architraves with one labour 50 x 15mm LM
-
K Glazing beads 20 x12mm LM -
Carried to Collection -
ITEM DESCRIPTION UNIT QTY RATE AMOUNT
WINDOWS
A
Allow for removal of existing pelmet boxes and replace with window blinds NO
-
B Allow for polishing and cleaning of terrazzo window boards LM
-
C
Supply, install and fix vertical window blinds from Ideal systems E. A Ltd or as approved SM
-
IRONMONGERY
D Supply and fix matching window handles NO
-
E Ditto window stays NO -
Carried to collection -
Summary
Carried to collection Pg 1 -
Carried to collection Pg 2 -
Carried to collection Above -
CARRIED TO GRAND SUMMARY
-
FIRST FLOOR ITEM DESCRIPTION UNIT QTY RATE AMOUNT
DEMOLITION AND REPAIRS
A
Take out existing painted blockboard partitions complete with timber framing complete with all doors and fitings 3500 mm overall height (areas along GM's offices, records, secretaries, commissioners, conference, committee, cinema and others) SM
-
B
Carefully remove parquet floor finish and prepare surfaces to receive granito floor tiles (GM's offices, secretaries, commissioners, conference, committee, cinema and other areas) SM
-
C Remove existing rubber tiles along the corridors and prepare to receive granito tiles (section B to A) SM
-
D
Allow for polishing and cleaning of existing terrazzo floor finish along the corridors along Staff officeto GM's) SM
-
E
Allow for wire brushing of existing external walls and columns to Project Manager's approval (entire wall with columns) SM
-
CEILING FINISHES
F Supply and fix 600 x 600 x 16 mm "Armstrong Fissured Minaboard" acoustic tiles fixed with metal suspended hangers as specified by manufacturers (GM's offices, secretaries, commissioners, conference, committee, cinema and other areas) SM
-
WALL FINISHES
-
PAINTING & DECORATING
G
Prepare and apply three coats silk vinyl emulsion paint to walls internally. SM
-
H Prepare and apply three coats silk vinyl emulsion paint ceiling surfaces SM
-
I
Prepare and apply three coats silk vinyl emulsion paint to corridor walls and columns including external walls SM
-
J Prepare surfaces and apply clear varnish to frames and door surfaces SM
-
K
Prepare surface and apply gloss paint to casement window, staircase railings. SM
-
-
FLOOR FINISHES -
Cement and sand 1:4 screeds -
L 30mm thick screed steel trowelled smooth SM
-
M
Supply and fix approved colour high quality polished granito tiles as “SAJ” or other equal and approved fixed with and including cement mortar and grouting joints with approved epoxy resin-based grout (section B to A) SM
-
N To skirting. LM -
-
O
Supply and fix carpet tiles size 500 x 500 x 6mm with fibre and rubber backing from Ideal floor systems E. A Ltd or as approved to parquet floors (GM's offices, secretaries, commissioners, conference, committee, cinema and other areas) SM
-
P
Supply and fix Gym rubbert tiles/mats from Ideal floor systems E. A Ltd or as approved to parquet floors (GM's records and ladies rest rooms) SM
-
Carried to collection -
ITEM DESCRIPTION UNIT QTY RATE AMOUNT
DOORS
A
Supply and fix 50mm semi solid core mahogany single leaf door size 700 x 2000mm veneered on both sides with lipping including frames and fanlight NO
-
B
Supply and fix 50mm Solid core single leaf flush door size 900 x 2000mm veneered on both sides with lipping including frames and fanlight NO
-
C
D
Supply and fix 3 lever mortice lock or approved equivalent complete with furniture. NO
-
E Ditto rubber door stops NO -
F
Allow for any required repairs to the door leafs to make good previous door locks locations. Item
WINDOWS
MILD STEEL CASEMENT WINDOWS
Purpose made steel casement windows manufactured from heavy duty frames in small panels size 200x250mm high incorporating permanent ventilating units complete with brass windows stays and fasteners
G
Allow for removal of existing pelmet boxes and replace with window blinds NO
-
H Allow for polishing and cleaning of terrazzo window boards LM
-
I
Supply, install and fix vertical window blinds from Ideal systems E. A Ltd or as approved SM
-
GLAZING
SOUND PROOFING
A
Double glaze windows with two layers of glass and inert gas or laminate two glass panels with acoustic PVB plastic film and line the window casements with rubber gaskets to provide Sound Proofing from Prime Aluminium Casement Ltd or as approved (Section E to B83) SM
-
Carried to collection
-
ITEM DESCRIPTION UNIT QTY RATE AMOUNT
Doors, frames and finishings in wrought Mahogany
B Quandrant 25 x 25mm LM -
C Architraves with one labour 50 x 15mm LM
-
D Glazing beads 20 x12mm LM -
IRONMONGERY
E Supply and fix matching window handles NO
-
F Ditto window stays NO -
Carried to collection -
Summary
Carried to collection Pg 2 -
Carried to collection Pg 3 -
Carried to collection Above -
CARRIED TO GRAND SUMMARY
-
