Contract Documentation Specifications

8/10/2019 Contract Documentation Specifications

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Contents

1. General 1.1 Introduction1.2 Uses of a specification

1.3 The specification and the contract drawings1.4 Types of specification

2. Writing the specification 2.1 Writing a specification2.2 ‘Escape’ clauses2.3 Appearance of a specification2.4 Basic order2.5 Alteration works2.6 Preliminaries2.7 Provisional and prime cost sums

3. Standard specifications 3.1 Office specifications3.2 The UK National Building Specification

4. Performance specifications

5. Sources of specification data

6. New work – representative specification

7. Works of alteration and repair 7.1 Redecorations and minor repairs7.2 Dilapidations7.3 Alterations and repairs

Appendices

A Extract from a specification for a new building

B Example specification for works of alteration and repair

© The College of Estate Management 2006

Paper 1434V5-0

Contract documentation: Specifications





Contract documentation: Specifications Paper 1434 Page 3

1 General

1.1 Introduction

The verb ‘to specify’ is defined in the Shorter Oxford English Dictionary as ‘to speakof or name something definitely or explicitly, to set down or state categorically or

particularly’.

A specification therefore may be defined as:

‘A description of an article or method so complete that it can be bought or built by others to the complete satisfaction of all concerned.’

Modern construction specifications arose from the development of competitivetendering systems and the consequent need for precise and contractually bindingdocuments that set out in detail all the contractor’s work.

Note, however, that although construction specifications are still most commonlyused to describe the work to be done, often in terms of the standards of materials and

workmanship required, specification writing skills are also required for draftingstrategic and project briefs and for statements of employer’s requirements underdesign and build procurement arrangements.

In one form or another, therefore, specifications form part of the contractdocumentation for most projects. Together with the project drawings, variousdescriptive schedules and sometimes bills of quantities, they provide tenderingcontractors with a complete and accurate picture of the work required.

1.2 Uses of a specification

1 Pre-tender stage

For small projects, the specification and accompanying drawings form the basis on which the builder prepares his estimate.

For larger projects, the specification supplements the drawings in providing theinformation on which the quantity surveyor bases his bills of quantities.

2 Contract stage

For ‘without quantities’ contracts, the specification is usually a contractdocument, carrying the importance attached to any contract document.

For ‘with quantities’ contracts, the specification is not usually a contractdocument unless it is incorporated into the bills of quantities. It is thereforeimportant, particularly where bills of quantities make reference to thespecification, that the specification should form an integral part of the bill.

3 Building stage

For contracts let both ‘with quantities’ and ‘without quantities’, thespecification is the major source of information for the quality of materials andworkmanship required. It will therefore be used by the contractor, architect,engineer and/or clerk of works as the definitive quality control document.

In addition, for ‘without quantities’ contracts the specification together withthe schedule of rates is the basis for valuing interim payments.




4 Final account stage

For ‘without quantities’ contracts, the specification together with the schedule of ratesis the basis for valuing variations and settling the final account.

1.3 The specification and the contract drawings

The purpose of the specification is to amplify the information shown on the contract

drawings so that all concerned can clearly understand what the designer requires.

Note that some specification information may be given in the form of notes on thedrawing, eg levels, figured dimensions, and details of some materials, and it is

pointless to repeat this in the written specification. It is plainly impossible to showabsolutely everything on the drawings – such as the precise details of how materialsare to be jointed or fixed, or the standard of workmanship required. However, thisinformation is important both for pricing and for quality control and so must be givenin some other form. Remember that the main purpose of the written specification is tosupplement and complement the drawn information, not to revise or supplant it. Thedrawings and specification together provide the full extent of the work to be done andthe standards the contractor is required to achieve. It is therefore important that:

The drawings and specification are complete but without excessiveduplication.

The drawings and specification do not contradict each other.

The specification writer knows exactly what is required. This demands a clearunderstanding of construction technology – both construction materials and theway in which buildings fit together – as well as a clear insight into thedesigner’s intentions.

The information is presented clearly and unambiguously.

1.4 Types of specification

There are many ways in which materials or workmanship may be specified, any or allof which may be used in a project specification. The following types are common.

1 Performance specification

Here it is the results to be achieved that are specified, rather than the means by whichthe results are to be achieved. Performance specifications are frequently used inmechanical and electrical services installations where the choice of equipment is leftto the contractor provided that specific performance standards are achieved.

eg: ‘Roof insulation is to provide a U value of not less than …’

The main advantage here is that contractor choice is maximised and the contractorhas the opportunity to use his skills and expertise to identify the ‘best value’ option.The major disadvantage is that the designer may want to be more specific about thetype of material to be used.

The development of performance specifications is considered in more detail inSection 4.




2 Descriptive specification

A selected product type is specified but no brand names are given.

eg: ‘Roof insulation shall be rigid non-combustible boards not less than 50mmthick and with a U value of not less than …’

This method still offers some contractor choice, but not as much as example 1.

3 Brand name (single product)

A specific product is named.

eg: ‘Paint shall be Smith’s “Decorite”.’

The main advantage of this approach is that it is very specific. Disadvantages are thatequally good and often cheaper materials may be excluded, and that it may beconstrued as a restrictive practice which may conflict with free trade legislation,

particularly in public sector projects.

4 Brand name with choice

One type of material is given as an example.

eg: ‘Paint shall be Smith’s “Decorite” or other equal and approved.’

This is an improvement on example 3, in that it allows substitutes to be employed.The main problem is ensuring that the substituted materials are equal in all respects tothe exemplar. In short, what does ‘equal’ mean in this context, and who is to give theapproval?

5 Brand name with multiple products

A number of alternative products are specified, any of which is acceptable.

eg: ‘Paint shall be obtained from one of the following approved manufacturers… .’

This attempts to overcome the problem of example 4 by allowing contractors to findthe lowest cost option from a number of specified alternatives.

6 Reference specification

Reference is made to some published standard.

eg: ‘Paint is to comply with Government specification W-101-12b.’

‘Drain pipes shall comply with BS…’




2 Writing the specification

2.1 Writing a specification

When writing a specification, adopt a layout that will enable reference to be madequickly to any item required. The standard format often adopted in the UK is thatused by NBS Services Ltd, following the co-ordinated project information system.

Note, however, that there is no mandatory ‘standard method’ for the preparation ofspecifications in the manner of the standard method of measurement for the

preparation of bills of quantities.

The phrasing and composition of a specification are too often undervalued. Only bycareful thought and repeated practice can clauses or provisions be so worded and

punctuated that they can be easily read and understood. Sentences should be brief andto the point, and long adjectival clauses avoided. The specification will come into thehands of people not necessarily acquainted with building. Technical terms areinevitable, but as far as possible the specification should be written in language asreadily understood by the layman as the technician.

In general the specification, being an instruction, must be in imperative terms, eg:‘Provide and fix hat and coat hook.’ To say ‘A hat and coat hook is to be fixed in ...’is incorrect and weak, but this form is frequently seen. Some writers use the futuretense ‘shall’, and therefore accepted forms are: ‘The contractor is to provide alltarpaulins ...’ or ‘The contractor shall provide all tarpaulins ...’ Terms should always

be definite and unambiguous, eg if ‘best’ is used it should be defined as meaning‘there is none better’. ‘Approved’ should be avoided as it leaves the choice open toexploitation.

Quality can be assured by quoting references to the relevant BS or other acceptedstandard, and workmanship by the appropriate Code of Practice. However, rememberthat these generally lay down the minimum acceptable standards, and Codes of

Practice are often multiple choice and may therefore entail further selection. Termsshould be used which have a relationship to the material or work under consideration – eg ‘forming’ an angle on a cement or other similar skirting, but ‘cutting’ a mitre ona wood skirting; ‘provide and fix’ a coat hook; ‘apply’ a coat of paint. In the sameway, one would ‘build’ a wall or block partition, ‘construct a roof or staircase’, ‘lay’ afloor or drain etc.

Terms frequently used in examination questions include ‘draft’ (write out in fullready for typing), ‘tabulate’ (present in the form of a table), and ‘schedule’ (present initemised form). You should read the question carefully to ensure that the answer is

presented in the required form.

2.2 ‘Escape’ clauses

Some specifications include clauses generally called escape clauses, eg: ‘Thecontractor is to allow for everything necessary for the due performance of the works,whether specifically mentioned herein or not.’

The effect of these clauses is to place the consequence of things left out and manyother misfortunes on the contractor. The specification should be as explicit as

possible and parts of the work which are uncertain should be covered by provisionalsums.

Certain omnibus clauses such as ‘test drains’ or ‘clean windows’ are usually

acceptable, but it is advisable to give as much information as possible, stating exactlyhow and when the drains are to be tested, or whether the windows are to be cleaned

by rag or leather and polished, and whether on both sides.




Such clauses as ‘all to comply with the requirements of the architect’ are notequitable, as it is the duty of the writer rather than the reader to decide what isnecessary and what is to be provided.

2.3 Appearance of a specification

The general appearance of the specification, as of any document, is important. The

layout of covers, titles etc should be given careful thought so that the result creates afavourable impression.

2.4 Basic order

Since a specification for all but very small jobs is inevitably a somewhat lengthy andcomplicated document, great care is necessary in its systematic arrangement, orderand composition if errors, repetitions, omissions and ambiguities are to be avoided.Although no two specifications are exactly the same, there are generally acceptedconventions for drafting a specification for a new building.

The first stage is to set out a basic skeleton list of the items to be specified. Thefollowing illustrates a typical skeleton list for a new house:

Skeleton list

Site clearance

Walls: external, load-bearing and non-load-bearing

External facings, sills, arch detail etc

Floors:

Ground floor: construction and finish

First floor: construction, including soundproofing, and finish

Roofs:

Pitched roof, construction and finish, insulation

Flat roof to integral garage, construction and finish, vapour barrier andinsulation

Fireplace to lounge

Internal ceiling and wall finishes – plasterwork, board and plastic finish toceilings, cornices, skirtings etc

Windows: type, glazing and internal finishings

Doors: type, frame and finishings, furniture Fitments: kitchen furniture, linen cupboard etc

Staircase: construction and finishings

Plumbing: fitments, pipes and connections etc

Drains: main drain, soakaways etc

Services: main water; heating system; domestic hot water; gas; electrical;waste disposal unit; mechanical ventilation to kitchen (canopy over cooker) etc

Site works: drive-in for car, paths, landscape work, formation of entrance from public road etc

Additional items: telephone service, TV connections to rooms, cables to roofetc.

From this outline each section will be taken and developed and put into order underthe headings selected for the specification. For instance, in the development of thetimber floors, subheadings could be listed as follows:




Floors

Plates

Joists

Trimming

Strutting

Bridging pieces

Insulation

Boarding – type, whether base for tile cover, ie ply, chipboard

Hearth margin to lounge fireplace

Attendance items for other trades.

Finish to floors (other than boarding)

Parquet floor to lounge: sub-floor – boarding

Materials

Thickness

Pattern and border

Laying, sanding and cleaning

Polishing

Protection

Plastic floors to kitchen, bathroom, toilet: sub-floor – plywood

Thickness and size of tile

Manufacturer and colour reference

Laying

Protection.

Three basic approaches are commonly used for the general arrangement of thespecification:

1. Trade form

2. Co-ordinated project information work section form

3. Elemental form.

Whatever arrangement is used, the contents are of course broadly the same. Theessential difference is simply one of arrangement and presentation. From the point ofview of the lay reader, the advantage is probably with the elemental form.

An example specification for a new building, written in the traditional form, is given

in Appendix A.




1 Trade form

Here the building is regarded as being the product of the operations of each of themany trades employed in the construction process.

First there is a section dealing with preliminary matters.

Then there is a series of sections each with the title of a particular trade,defining the materials and workmanship of the trade and describing what is to

be built by it, eg:

Excavator

Bricklayer

Carpenter and joiner

Drainlayer.

2 Co-ordinated project information work section form

Here the specification is arranged according to the work sections defined by the UKCommittee for Co-ordinated Project Information (CCPI), which attempts to improveco-ordination of all contract documents (drawings, specifications, bills of quantitiesetc) through the use of a standard document coding system. Under this protocol, thespecification is divided into work sections in the same way as SMM7. Examples are:

A Preliminaries/general conditions

D Groundwork

D20 Excavating and filling

D30 Piling

E In situ concrete

E05 Mixing/casting/curing in situ concrete

E20 Formwork for in situ concrete

K Linings/sheathing/dry partitioning

K10 Plasterboard

K30 Panel partitions

K41 Raised access floors.

3 Elemental form

Here the building is regarded as being composed of a number of constructionalelements, such as foundations, floors, walls, roofs.

The specification opens with a section dealing with preliminary matters.

Next is a section entitled ‘materials and workmanship’, in which all materialslikely to be required in the job are described, together with the standard ofworkmanship required for each.

Then follow sections dealing with what is required to be built in constructingthe various elements, each with the element title, eg:

Foundations

External walls

Roof

Internal finishings.

Within each elemental section the contents are arranged in trade order.




2.5 Alteration works

For works of alterations, additions and maintenance repairs it is generally necessaryto depart from the above forms, due to the nature of the works. Each job must begiven special consideration so that it may be described in as logical and reasonable anorder as possible. In some cases the sequence in which the work is executed may befollowed; in others it may be better to describe each room or section separately; or thework may be partly or entirely grouped as for new work. Whichever form of

specification is being written, the real test of its effectiveness is that it should be precise, concise, and should anticipate and answer all the contractor’s questions.

The specification would open with ‘preliminaries’, followed by ‘materials andworkmanship’, followed by the ‘works’ clauses grouped in whatever manner has beendecided on.

Alteration works are considered in more detail in Section 7, and an example of part ofa specification for alteration works is given in Appendix B.

2.6 Preliminaries

The term ‘preliminaries’ covers those clauses that govern the general conduct of thecontract and define the extent of the contractor’s liability. Most of the conditions ofcontract, either in full or as reference to a printed form of contract, are embodied inthe preliminaries. Where the JCT form of contract is to be used, the specificationshould also give the information that will ultimately fill the blanks of the appendix tothe contract. The importance of this will be obvious if reference is made to thatappendix.

Following this reference to the conditions of contract, instructions will be includedfor:

Plant, scaffolding and tools etc Sheds for storage of cement etc

Sanitation for workpeople

Welfare and messing arrangements for operatives

Water for the works

Artificial lighting and power

Foreman and his office, office maintenance and telephone

Similar facilities for the clerk of works

Payment of rates on temporary buildings

Notices and fees

Other similar requirements.

Most standard methods of measurement of building works give a comprehensive listof items to be written into the specification as preliminaries. Works on site anddemolitions are dealt with as trades and are not generally regarded as preliminaries.

2.7 Provisional and prime cost sums

Provisional sums may be defined as sums included for work that cannot beadequately described. Such items are included in the specification as lump sumswhich must be included in the contractor’s price, and which the architect reserves the

right either to spend or deduct in the final account according to how much of the workto which they refer is actually carried out. A provisional sum is therefore intended tocover the total cost of a section of work known to be required but whose extent isuncertain at the time of preparing the specification. A simple example is the increaseddepths of foundations required in a particularly unstable part of the site.




Prime cost (PC) sums are used for work to be executed by a nominatedsubcontractor, or for material to be supplied by a nominated supplier, and aregenerally based on quotations received from specialist firms. These sums do notinclude main contractor’s profit, and items should be given in the specificationagainst each sum to allow the contractor to price for main contractor’s profit and anyattendances required. A PC sum therefore represents the cost to be paid by the builderto the vendor after all trade discounts and commissions other than cash discount have

been deducted.

In previous editions of the JCT standard building form of contract a vendor may have been offering the supply of (1) goods alone, when the cash discount will be 5%, or (2)services alone or goods together with services. In the case of (1), the vendor became a‘nominated supplier’ and in (2) a ‘nominated subcontractor’. In operating a clauserelated to a PC sum, the architect retained direct control of price and quality. Forexample, ironmongery may have been specified by way of a prime cost from anominated supplier, or electrical installation by a prime cost from a nominatedsubcontractor. There are no clauses for nomination in JCT 05.

A typical PC sum item might therefore be:

Note that not all forms of contract support the use of nomination for subcontractorsand suppliers. Where nomination is not supported in the chosen conditions ofcontract, but the architect nonetheless wishes to exercise some degree of control overwho does the work, then the work is usually included as a provisional sum.

Both provisional and prime cost sums will be substituted by the agreed, measured orascertained value of the work actually done at the settlement of the account.

Lounge/dining roomInclude the prime cost sum of £1 500 (one thousand five hundred pounds) for roomdivider to be supplied and delivered to site by a firm to be nominated by the architect.

Add for profit

Add for fixing to prepared lintel enclosure, vinyl-covered folding door in two leaves withaluminium frame and fittings (Messrs Blogg’s catalogue No 345) to suit opening 2150 ×2050mm, all in accordance with the manufacturer’s written instructions.




3 Standard specifications

3.1 Office specifications

In practice, it is often possible to select, with little alteration, all the clauses in the groupsso far considered from a standard office specification for jobs of a similar kind.

However, it must be emphasised that this quite normal method of building up onespecification from another has several disadvantages and dangers.

In the first place, it is essential to be sure that the original is a good specification – ie,one which is clear, complete, concise, specific and technically accurate. If this is notthe case, then using a bad model will simply perpetuate previous poor practice. Major

problems include:

Copying clauses from the ‘standard’ which are irrelevant to the job in hand, the purpose of which then becomes unclear.

Overlooking small but significant differences or improvements between one job and another, or specifying materials which are no longer available.

It is therefore necessary to consider very carefully the special conditions required foreach contract, particularly when selecting preliminary clauses. Descriptions ofmaterials are usually available from previous jobs, but in the case of special or newmaterials the manufacturer will usually provide whatever details are necessary toenable the correct description to be drafted.

Note that government departments, some local authorities and large estatemanagement offices concerned with the care and maintenance of buildings frequentlyadopt standard printed preliminaries and materials clauses. The work clauses are then

prepared as a schedule of works in order of execution, or by trades and added to thestandard printed sheets, the last of which refers to the schedule and the number of

pages it contains.

The works clauses require a sound knowledge of building materials, construction,organisation and common sense and demand an accurate visualisation of the work.They call for little or no stereotyped phraseology, but clear, correct and concise English.

Some (mainly public sector) organisations have a comprehensive standardspecification which is issued complete and in full for every project. The rationale forthis is that if the standard specification is truly comprehensive, there should be noneed to prepare bespoke specifications for each separate project.

In practice, difficulties with updating the standard specification and the introductionof new design philosophies and materials mean that the standard specification almostalways needs amendment for particular schemes.

The most common way of doing this was to issue the standard specification in full,often termed the general specification, and to supplement it by a further document,often termed the particular specification, containing the amendments required to suitthe scheme in question. The basic idea was that the general specification and the

particular specification together detailed the works.

This rather cumbersome practice often caused significant problems, principally due tothe sheer volume of documentation provided but also because of contradictions

between the two documents and between the documents and the project drawings.

Fortunately, the development of computer-based standard specification libraries andthe widespread use of word processors has led to the substantial demise of thisarchaic and error-prone practice.




3.2 The UK National Building Specification

Some years ago in the UK, the RIBA set up an organisation to develop and publish a National Building Specification at the request of the Government’s EconomicDevelopment Committee, the Department of the Environment, the Greater LondonCouncil and the British Standards Institution. The idea was to produce a standardlibrary of clauses covering all matters, so that a specification could be assembledfrom the standard clauses rather than being written from scratch.

The National Building Specification (NBS) is therefore both a collection of standardclauses and technical guidance to help the specifier to decide which clauses areappropriate for a particular project. In the preface to the NBS, Sir Robert Matthewdraws attention to its objectives, being to improve the technical content, language andarrangement of specifications and achieve a large-scale appreciation of the NBS as a

project document.

The inclusion of standard clauses is at the option of the specification writer – whomay in some instances prefer his own clause. Parts of the clauses can be rejected ifirrelevant, and all clauses have a unique reference. The phrase ‘the contractor shall’has been omitted, on the basis that the whole specification will be directed to a

contractor eventually. Work sections are classified according to the CCPImethodology. Specific item commodity clauses are written in two parts separated bya colon:

A statement identifying the commodity:

A qualitative statement about it.

For example:

Steel mesh: expanded metal fabric to BS 405 galvanised to BS 729 and coatedwith bitumen.

The workmanship clauses are written as instructions to the contractor as a series ofstatements in a sequence, set out so that the reader can readily ‘scan’ the information.

For example:

PATTERNED GLASS: fix the following types …. EDGE CLEARANCE: to be equal all round each pane and not less than 3mm.

At the beginning of the NBS attention is drawn to the significance of the specificationand the circumstances when it is a contract document. Usually the specificationincludes qualitative description clauses and a schedule of works. The schedule can

include location, items in detail and dimensions of work which cannot be or are notshown on the drawings.

NBS is now available by subscription, either as a printed document which can be photocopied and used as a typing draft, or as a CD-ROM which can be used withword-processing systems. It is updated from time to time as required.




4 Performance specifications

In Section 3 we examined the traditional method of specifying. We now considerwhat may be in some instances a more logical methodology.

If the client’s requirements can be expressed in terms of performance, then the principles of performance specification referred to in Section 1.4(1) above may be

applied to the specification as a whole rather than simply to isolated components orassemblies. This enables those pricing and executing the work to use their specialistknowledge and skills to put forward the ‘best value’ solution provided that thespecified performance standards are attained.

If this approach is to be used, however, it is essential for the designer andspecification writer to be able to establish the client’s precise performancerequirements for the work involved, and to convert these requirements into asufficiently comprehensive specification.

As a beginning, therefore, it is necessary to set down in unambiguous terms:

The properties and performance that will be the basis of the designrequirement.

These frequently turn out to be optimistic in terms of time and money available, andalso contradictory, which will then lead naturally to –

Prioritisation and compromise.

Once the desired performance criteria have been identified, the next task is to set –

Measurable minimum and maximum limits of performance, together with

appropriate means of measurement and testing.

In some cases present knowledge and research allow this to be done quickly, but inother cases it is necessary to establish the limiting values through further research.

The size of this task is frequently underestimated. As an example, consider the problem posed by a performance specification for cleaning services in a hospital. Forgeneral public areas it may be possible to set the required cleanliness standardsrelatively simply, eg by specifying that floors are to be kept swept and clear ofdiscarded rubbish, that waste bins are to be emptied twice a day, etc. But consider thecase of an operating theatre or food preparation area. Here standards need to be muchhigher, including not only routine sweeping, polishing and the removal of rubbish butalso ensuring that surfaces are kept clear of bacteriological contamination. Devisingappropriate and robust standards, measurement and testing regimes for this kind ofwork may be extremely difficult.

The following list provides one basis on which a performance specification may be prepared. It gives a general outline, without stating the properties to be given or thespecific amount of information to be developed under each of the headings. Thissequence does not restrict the information that may be required: it merely gives asystem order and therefore, incidentally, provides a checklist.




Document, scope and information for indexing

Identification

Generic name

Product name

Short description

Related documentation

Description

Composition

Manufacture

Accessories

Shape

Size etc

Appearance etc

Climate, site and occupancy conditions

Characteristics relating to behaviour in use and working

Structural etc

Fire

Gases

Liquids

Solids

Biological

Thermal, optical, acoustic

Technical

Energy

Compatibility Durability, reliability

Workability

Maintenance

Applications

Site work, maintenance, prices, supply, technical services

References.

An advantage of this system is that it is not confined to the UK and consequently theuse of technical documentation from other countries is facilitated.

At this point, therefore, we can define a performance specification as:

‘A document setting out a client’s needs by listing the essential properties in aregular and systematic form and including the limits of the performance, testing,maintenance and any other required qualities.’

This allows the contractor, manufacturer or supplier to have the freedom of design,innovation or even selection from his standard products as well as the freedom ofmanufacture and assembly.




Use of performance specification

In many ways performance specification has been used for a long time, although itsuse has been somewhat crude, with low level description. For example, it issometimes stated that the cold water storage tank will be ‘… supported on stout

bearers’, the choice being left to the contractor. In an operational form this may bemore explicit, eg ‘... supported on 100 × 75mm sawn softwood bearers’.

Many British Standards for materials and components include performances.

The Agrément Board considers and publishes performance requirements, methods ofassessment and tests.

The UK Building Research Establishment is also involved in preparingspecifications for performance, eg for windows. The relationship of performance

between the various materials and products is obviously very close, and performancesare interdependent.

Performance specifications have also been widely used for many years for a numberof different types of work, particularly those where the technology is specialist and

complex and for which specialist companies have developed particular ways ofovercoming difficult problems. Examples include mechanical and electrical systems,IT installations, lifts and escalators, high rise curtain walling systems and lowvibration piling. In these cases the specifier can specify the performance which theinstalled work is required to attain, thus allowing various specialist contractors to putforward their own solutions.

For high rise curtain walling, eg, in addition to specifying the basic elevational layoutand appearance of the infill panels, the specifier might also wish to include factorssuch as:

Wind and impact loadings

Self-cleaning properties

Air and water permeability

U-values

Provision for cleaning and repair

Measures to limit progressive collapse in the event of failure, etc.

The statement of employer’s requirements, required where projects are to be let onsome form of design and build basis, may be seen as a specialised form of

performance specification. In the case of a new factory building, eg, the employermay specify things such as:

Location of building and building footprint

Schedule of accommodation

Overall dimensions

Clear distance between columns

Overall useable floor space

Appearance of the external finishings

Details of building performance characteristics, including U values, noisesuppression etc

Maintenance characteristics.

These requirements could all be satisfied in many different ways – again,specification of the building in this way rather than in the more traditional

prescriptive form enables tendering contractors to put forward innovative and cost-effective design solutions.




Remember that a complete structure consists of a number of parts, and it is therefore possible to establish a priority or hierarchy of performance both for a building as awhole and for each of a building’s systems and constructional elements. We must,however, recognise that all the components in a building, and indeed all the elements,are related and dependent. The completed building is a result of successfulrelationship and dependence. It follows that the performance of the building as awhole must be decided first, before the various sub-considerations can be examined.

The procedures involved will vary from job to job, office to office, source to sourceand so on, but the general routine is illustrated diagrammatically in Figure 1.

Note that contractors undertaking work on the basis of performance specifications

will carry a much higher liability to the employer than those tendering in a moretraditional form of specification. In particular, it is now well established law that,unless specifically excluded in the contract, liability will extend to providing a

building or an installation which is fit for its purpose.

Significant cases in which this issue has been explored include Greaves & CoContractors v Baynam Meikle (1975), International Broadcasting Authority v EMI

Electronics and BICC Construction (1978), Newham LBC v Taylor Woodrow(Anglian) (1981), and Viking Grain Storage v TH White Installations (1985).

FIGURE 1

Overall strategy decidedEg: specify whole construction, or elements, or components.

↓

Decision on scope of performance statementEg: the context in which the building is to be designed and components fixed; geometry of

the spaces, jointing, fixing, appearance.

↓

Decision on functional requirementsEg: temperature requirements of space, thermal requirements.

↓

Decision on relative importance of propertiesEg: essential, reasonably important, desirable, relevant but not essential.

↓Decision on measurement and quantification of required properties

Eg: tests, measurement, units, BS, CP, Agrément Certificate.

↓

Statement of limiting values Eg: limits, upper and lower, that will be tolerated when the component is fixed and in use,

and whether or not there will be different levels in different circumstances.




The higher the level of specification, the greater the opportunity for innovation.However, it is progressively more difficult to draft a document that includes

performance parameters which are both comprehensive and testable.

One disadvantage of performance specifications is that to some extent the purchaserloses part of his influence over the design. If more positive control of this element isneeded, a more traditional form of specification is likely to be appropriate. Some

control can, however, be exercised, such as maximum dimensions where space orvolume requirements are dictated by other constraints.

5 Sources of specification data

Common sources of specification data include standards published by variousnational and international bodies, standard specifications published by major clientsand government bodies, manufacturers’ data, trade associations, and data sheets

published by bodies such as the UK Building Research Establishment (BRE). Someof the most commonly used around the world are briefly reviewed below.

British Standards and Codes of Practice

The British Standards Institution (BSI) is the approved body for the preparation ofUK national standards covering quality, dimensions, tolerances and tests. The mainobject is to set up recognised standards to simplify production by eliminating thewaste involved in producing an unnecessary variety of patterns and sizes for the same

purpose.

The British Standards for Building Materials and Components are summarised in BSHandbook No 3, which indicates the different types and qualities but does not givefull details of tests. It is important to note that in many cases the Standards give

alternative qualities. For example, BS 417 provides for two grades of galvanised mildsteel cisterns. It is essential to give the particular type required in a specification.

The BSI also publishes Codes of Practice which lay down standards of good practiceand workmanship. They generally take the form of recommendations, but some aregiven in the Building Regulations as accepted standards, eg CP 114 (Structural use ofnormal reinforced concrete in buildings). A thorough knowledge of all the Codes ofPractice will obviously take a considerable time to acquire, but you should have ageneral knowledge of the matters covered in order to be able to assess their uses andlimitations.

The Codes of Practice are usually divided into the following sections:

General

Scope and definitions

Materials

Selection and standard of quality of materials and fixing accessories

Design considerations

Basis of design and functional requirements

Workmanship

Preparatory work off site and erection on site

Testing and inspection

Maintenance and protection

Illustrative figures.




International Organization for Standardization

The International Organization for Standardization (ISO) is a worldwide federation ofnational standards bodies from some 140 countries, one from each country. ISO is anon-governmental organisation established in 1947. Its mission is to promote thedevelopment of standardisation and related activities in the world with a view tofacilitating the international exchange of goods and services and developing co-operation in intellectual, scientific, technological and economic activity.

ISO’s work results in international agreements which are published as InternationalStandards.

ISO is not an acronym. In fact ‘iso’ is derived from the Greek isos, meaning ‘equal’.The prefix ‘iso’ occurs in a host of terms, such as ‘isometric’ (of equal measure ordimensions) and ‘isonomy’ (equality of laws, or of people before the law).

The name ISO is used around the world to denote the organisation, thus avoiding the plethora of acronyms resulting from the translation of ‘International Organization forStandardization’ into different languages. Whatever the country, the short form of theorganisation’s name is always ISO.

Agrément Board certificates

In 1966 the UK Minister of Public Buildings and Works announced the formation ofan independent authority to assess new materials and components proposed for use inthe building industry. This authority, the Agrément Board, has a director and acouncil representing the main interests of the building industry and a team ofassessors from interested government departments and the British StandardsInstitution. Its purpose is to carry out the recommendations of the White Paper ‘TheAssessment of New Building Products’, produced by a committee under thechairmanship of Sir Donald Gibson. This committee examined and confirmed theneed in this country for certificates of approval similar in form to those already inoperation in France and other European countries.

Agrément certificates are normally drawn up in specific terms. The certificate statingthat a product is considered by the Board to be satisfactory will relate to a definedmode of manufacture which will be subject to periodic checks by the Board to ensuremaintenance of quality, a specified factory or other place of manufacture, andspecified uses in building.

Certificates normally have limited duration of validity – up to three years in the firstinstance and renewable for a further period of not more than three years. Certificatesare withdrawn if the conditions of issue, including those mentioned above, cease to becomplied with. In order to qualify for certification, the material or process must benew to the building industry, or a known material must be used in a novel way.Because of this, certificates are not normally issued for products covered by BritishStandards or for processes covered by codes of practice.

For a certificate to be awarded, the product or process must be in full-scale production, although the Board is willing to test pilot-scale production and to saywhether a certificate would be likely to be awarded if full-scale production took

place. As to testing procedures, the use of the material in the building has to bespecified and, where applicable, the details of fixing to other components. In general,a material as such will not be tested, but rather a material in its proposed situation inconjunction with other parts of the structure.

The Board has a checklist of performance requirements and methods of assessmentand test. The cost of the testing is borne in full by the manufacturer.




Manufacturers’ literature

This is becoming an increasingly important source of information due to the vastquantity of new materials now being used in buildings. Catalogues, which cannormally be obtained free of charge from manufacturers, form a useful technicallibrary.

Manufacturers tend to be optimistic regarding the performance of their materials, but

the methods of fixing they give should be strictly adhered to and written into thespecification. When using an old specification as a guide, care should be taken not tospecify obsolete materials, and each clause must be relevant to the particular job inhand.

Trade associations

There are several trade associations which produce informative literature. Some UKexamples are:

Brick Development Association

Lead Development Association

Copper Development Association Zinc Development Association

Aluminium Development Association

Cement and Concrete Association

Coal Utilisation Council

Timber Research and Development Association.

Building Research Establishment Digests etc

These take the form of papers dealing with some special aspect of construction: forexample, BRE Digest No 8 (second series) deals with built-up felt roofs. They cover

such matters as workmanship, performance, precautions to be taken to avoid defectsetc. In many cases recommendations are eventually incorporated into codes of practice. This source of information can be obtained by a nominal annualsubscription.

Advisory leaflets are mainly intended for the small builder, clerk of works, foremanand craftsman. They give information in a practical and concise form about the resultsof research and the latest developments in building practice, and cover a wide rangeof topics concerning such matters as materials, workmanship, powered hand tools,site costing, programming etc.

The various professional and technical journals give details of new publications and

articles on materials and techniques. Articles are usually headed with the appropriateclassification reference so that the pages can be extracted and filed with otherinformation in the same topic.

American institutions

American standards are used in several parts of the world, particularly in the Far Eastand South America, as well as in the USA. The most commonly used are those

published by the American Society of Testing and Materials, which was establishedin 1898 as an international society devoted to ‘the promotion of knowledge of thematerials of engineering and the standardisation of specifications and the methods oftesting’.

Another widely used set of American reference standards are those published by theAmerican National Standards Institute (ANSI). ANSI develops standards formaterials and testing procedures and works closely with other bodies around theworld.




6 New work – representative specification

An extract from a specification for a new building to be constructed under a plan andspecification type contract, together with outline drawings, is included in AppendixA. When reading through the clauses it is worth visualising the work involved andconsidering alternative forms of construction that might have been used, and howthese could have been described.

This particular specification is arranged in trade order.

7 Works of alteration and repair

7.1 Redecorations and minor repairs

1 Generally

Architects and surveyors are often called upon to prepare specifications for works ofalteration and repair including redecoration. Moreover, the preparation of schedules

of dilapidation frequently forms part of professional practice, and here toospecifications are needed.

2 Redecoration

The general order of a specification for works of redecoration follows the generalsequence:

Preliminaries

Materials and workmanship

Works required.

The section dealing with the works is normally arranged on a room basis, starting atthe top of the building and working round each floor in a clockwise direction,descending floor by floor. Then the roof and external elevations are examined, againin a clockwise direction. This approach enables the builder to inspect the building andascertain the extent and nature of the work required in a logical order while readingthe specification, with the minimum need to retrace his steps. This is an importantconsideration on his part, since the work is physically tiring and undue fatigue on the

part of the estimator may lead to inaccurate estimating.

Works of redecoration, by their nature, are largely repetitious, similar work beingrequired in each room and varying only in extent. Usually minor repairs (such as

making good damaged plaster or reglazing broken glass) are covered in such aspecification, since they are usually seen to during redecoration.

The preparation of surfaces prior to repainting needs careful description. Thematerials and workmanship section of a redecoration specification will thereforecontain appropriate descriptions of the preparation of surfaces and the manner ofmaking the minor repairs commonly to be expected, in addition to describing thematerials and workmanship to be used. The descriptions in the works section cantherefore be shortened by referring to the materials and workmanship clauses.However, where a particular item occurs once only, it may be desirable to describethe preparation and manner of repair with that item in the works section for greateremphasis.




The following are typical clauses for dealing with external work which has been previously painted.

Alternatively, a general clause could be inserted dealing with preparatory workapplicable to the whole of the painting and other conditions as to application of the

paint, following on with an abbreviated clause, eg:

Internal paintwork will be dealt with in a similar manner, starting with a generalclause as to preparatory work etc, or as follows:

External woodworkCut out, prime rebates and renew all defective putty in sashes. Wash off, rub down with

pumice stone and water, or burn off where necessary, bring forward, stop and paint oneundercoat and one coat of gloss on all surfaces previously painted. Painting is to be done

only when surfaces are free from moisture.

External ironworkWash off, remove all rust and loose and defective paint by scraping and wire brushing.Prime bare places and paint the whole with one coat of Messrs .….. anti-corrosion

preparation and prime and paint one coat of gloss paint. No coat is to be applied until the previous one is hard dry and the painting to be done in dry weather when the work is freefrom moisture or condensation.

External stucco workAll surfaces to be cleaned and wire-brushed if necessary, painted with one coat ofstonework priming, faced up where necessary, and then painted one undercoat and onecoat of gloss paint to approved colour. The surface to be thoroughly dry before the firstcoat is applied and no coat to be applied until the previous one is hard, dry and free frommoisture.

External ironworkPrepare as before specified and paint two coats to all ironwork previously painted.

Old plastered walls in bad condition or previously paintedRemove all old distemper, paper etc, stop, rub down, size, line walls with stout white

paper and apply two (or three) coats of undercoating and one coat of eggshell gloss ofapproved shade. Each coat to be hard dry before the next is applied.

Plastered walls previously paintedWash off, prepare, stop and touch up, apply one undercoat and one coat of eggshell glossin similar colour to existing.

Painting plastered walls previously distempered

Remove all distemper and leave walls perfectly clean and dry. Rub down, make goodwhere necessary and apply one coat of priming, two undercoats and one coat of eggshellgloss of approved colour. Each coat to be hard dry before the next is applied.

Internal woodwork previously paintedWash off, stop, face up all uneven surfaces, rub down, touch up bare places, paint one (ortwo) undercoat and one coat of gloss of approved colour. Each coat to be hard dry beforethe next is applied and painting to be done only when surface is free from moisture.

Ceilings and walls previously distemperedWash off plastered surfaces, cut out and make good cracks with Keene’s cement (or

plaster of Paris). Touch up all making good, claircolle and twice emulsion.




Other typical clauses applicable to works of redecoration and minor repairs wouldinclude:

EXTERNALLY

GenerallyAll work of repair is to match existing work.

RoofsRefix all slipped slates, remove those broken and replace with new, including replacingany missing, and leave the whole of the slating sound and watertight. (Allow provisionallyfor 20 new slates.)

Remove 2 No defective chimney pots and provide and bed new flaunched in cementmortar 1:4.

Rake out and point defective brickwork in chimney stacks, coping, parapet and party wallsabove roof level in gauged mortar 1:1:6.

Make good cracked and defective fillets and flaunchings in ditto.

Repoint ridge and hip tiles in ditto.

Overhaul and clean out gutters.

Remove defective lead to flat roof and in flashings and provide and lay new Code 5 leadand wedge and point flashing.

South elevationRake out and point defective brickwork in gauged mortar 1:1:6. (Allow provisionally5m².)

Uphold as required and cut out defective brickwork where bulged or settled and rebuild incement mortar 1:4. (State clearly the extent of this work or give provisional areas.)

Take out broken and defective stonework to sills, steps, landings etc and provide and buildin new Portland stone ditto in gauged mortar 1:1:6.

Rake out defective pointing around window and door frames and repoint with mastic.

Remove the defective stone coping to the parapet wall, take down brickwork out of plumband rebuild in cement mortar 1:4 using old bricks where possible and making out withnew.

Bed new 300 × 75mm Yorkstone weathered and twice throated coping bedded and pointed in cement mortar.

Hack off the defective rendering and make good in Portland cement and sand 1:3 finishedwith a wood float.

Remove decayed sills of sash and door frames and provide and splice in new oak ditto.

Take out decayed sashes and rails and provide and fix new and prepare and paint threecoats of oil colour.




A clause might also be required for cleaning out manholes, gullies and cisterns.

7.2 Dilapidations

A schedule of dilapidations is usually prepared as a result of a tenant’s breach of his

covenant to repair. The schedule is simply a list of defects, each of which constitutesa breach of covenant, issued to the tenant with a notice informing him that he is in

breach and requiring him to carry out repairs. Normally no specification material isincluded in the schedule.

However, a specification of work required in remedying the defects which constitutethe breach of covenant is eventually required, either to ensure that, where the tenantundertakes to repair, an appropriate standard of repair is achieved, or to settle thevalue of the works where the tenant offers monetary compensation rather thancarrying out the work.

INTERNALLY

Second floor south bedroomCut out cracked or bulged ceiling plaster and lath plaster, float and set.

Cut out loose or bulged plastering to walls, rake out joints as key and render and set (orrender, float and set). (Note: This repair will necessitate making good of paper or

distemper as the case may be unless the whole of the room is being redecorated.)

Cut out cracks in ceilings and make good in Keene’s cement.

Replace defective length of cornice and make good new to match existing.

Renew sash lines (stating quality). (Note: In dealing with sash cords it is usually better toreplace both the cords of the sash at the same time when one is broken – the second one

being replaced for little more than the cost of the cord while the sash is out.)

Take out defective beads and pocket pieces to double hung sash and provide and fix newand prepare and paint new woodwork.

Cut out split panels in doors and provide and fix new and paint as before.

Hack out broken squares of glass and reglaze to match existing.

Repair defective rendering to back hearth.

Take out defective firebrick back and cheeks to grate and renew.

Wash, stop and twice emulsion ceiling, cornice and frieze. Strip and stop walls, prepareand hang wallpaper to choice £x per piece book price. Clean, bring forward, touch up,

prepare and paint one undercoat and one coat of gloss on all wood and ironwork

previously painted.

GenerallySweep flues, clean windows inside and out, re-washer taps, oil locks, replace missingkeys, scrub floors and leave premises ready for occupation.




The extent and nature of the work that can be required of a tenant is entirely governed by the wording of the repairing covenant. Compliance with this covenant might notsatisfy an incoming tenant, who might well require a higher standard. Nevertheless,the quality and extent of the works included in a specification prepared in order tocomply with a repairing covenant should include only such works as the tenant isunder covenant to carry out. The precise wording of the repairing covenant istherefore important, and, before starting to prepare the schedule of dilapidations andthe subsequent specification, the architect or surveyor must satisfy himself as to themeaning of the words used.

These considerations apart, however, a specification prepared for dilapidations issimilar to any normal specification dealing with work of repair and redecoration.

7.3 Alterations and repairs

Writing a specification of works of alteration and repair, particularly where the workis extensive, is perhaps the most interesting aspect of specification writing and theone that makes the greatest demands, not only on the writer’s knowledge of building

but also on his ability to analyse the work as a whole so that it may be presented

accurately, clearly and logically to the builder. Here above all it is necessary to stepinto the shoes of the builder, to anticipate and answer all his questions, and to leadhim round the existing building with the minimum of effort on his part.

Obviously, in addition to being thoroughly conversant with the job before drafting thespecification, it is necessary to visit the site and make notes, or even draft full clauseswhile there.

Drafting the individual clauses does not normally present much difficulty. Theimportance lies in the approach to the job as a whole. The order usually adopted isagain the typical one:

Preliminaries


Works required.

The works section is likely to be arranged in a room-by-room order. Remember,however, that an alteration may affect more than one room – eg forming a newdoorway between two existing rooms. It may then be convenient to group roomstogether, or, if they are kept separate, to specify the new doorway in the sectiondealing with one of the rooms and to mention this in the section dealing with theadjoining room.

Again, an alteration may affect a whole floor, eg removing existing and providing andlaying new floorboarding to the whole of the first floor. Here it may be convenient tospecify this work under its own heading before dealing with the work required in eachroom on the first floor.

These considerations apart, the overall order should be on a clockwise, room-by-room, floor-by-floor basis. It is important that each room, floor or elevation referredto in the sections of the specification is clearly named and can be clearly identified onthe site. It is usually best to refer to rooms by their existing use rather than their futureuse, since the builder will be faced with the existing building and might easily beconfused if future uses only were referred to. Of course it is often possible to give

both existing and future use, eg existing bedroom No 4 – future bathroom No 1, but

where an existing room disappears on conversion by being thrown into another, this isnot always possible.




For extensive alterations it is helpful to append to the specification a single line key plan of each floor of the building showing the position and name of each roomtogether with the north point. For smaller jobs such a key plan may be over-elaborate,and it may not be possible to give rooms clearly identifiable names. One should thenadopt as standard practice the habit of looking at the building from the front andreferring to a room by its general position on the right-hand or left-hand side, andfront, centre or rear of the building, or by its relationship to a previously describedroom, thus:

Ground floor

Front right-hand room

Front left-hand room

Rear right-hand room

Rear left-hand room

Rear room next last

Rear back addition right-hand room

Rear back addition left-hand passageway

Extreme rear room, back addition.

Additions

Where the work of alteration includes the construction of an addition, and thus aconsiderable amount of new work, the new work can be specified in the usual trade orelemental order complete with the appropriate preliminaries and materials andworkmanship clauses. When the alteration work is later specified, it will then form aseparate section of the specification (itself arranged on a room-by-room basis). Thissection can open with a statement that the descriptions of materials and workmanshipgiven for the new works are intended to apply equally to the alteration works.

Where a window or door in the existing building has to be altered to match those inthe addition, the removal of the existing window or door and the necessary alterationof the existing opening will be specified in detail under alterations, together with anote that a new window or door (all as previously specified in new works) is to be

provided and fixed in the re-formed opening. Where the new works have to match theexisting, this must be stated whenever appropriate, eg ‘provide and fix in the opening

previously described, casement window glazed and painted complete and all to matchexisting adjacent in every respect’.

Openings

Where a new opening is to be formed in an existing wall, its finished size should begiven together with a description of the finish required at head, jambs and sill. Where

an existing opening is to be closed up, its existing size should be given together witha description of the manner of closure, usually ending with words such as ‘and leaveas if no opening had existed’.

Each item of alteration must be carefully considered, since work may be requiredwhich is not immediately obvious. For example, closing up an existing windowopening may require removal of the external arch if in faced brickwork, but if theexternal wall is finished with rendering the arch will be concealed and need not beremoved.

Salvageable materials

Alterations often generate salvageable material arising from demolition, eg sheet lead.This material belongs to the employer, of course. If the builder is allowed to removeit, he must allow its salvage value as a credit set off to the employer against the costof the works, and a suitable item must be given covering this.




Where the value of salvageable materials is small, it is sufficient simply to instructthe builder to allow the appropriate credit value in arriving at his prices. Where thevalue is likely to be large, however, the builder should be required to state the creditvalue of each salvaged item in addition to his price for carrying out the necessarydemolition or removal, so that it can be decided whether a proper allowance is beingmade. Normally work of this kind and extent is presented on paper with double cashcolumns, one for the credits and one for the price for the work, thus facilitating thenecessary entries by the builder.

Support

Demolition or forming openings usually requires temporary shoring and supportingwhile the work is carried out. Normally it is for the builder to decide the detail ofwhat is required, and the specification will simply remind him to make theappropriate allowance in his pricing by using words such as ‘Shore and support asmay be required and form new opening ...’ Where, however, the architect or engineerdesigns the shoring and thus removes the risk from the builder, such shoring will needto be specified in detail so that the builder may know what is expected of him and

price accordingly.

Restriction of movement

Working in existing buildings is always more expensive because of the restriction onthe freedom of movement of operatives, materials and plant. This is particularly thecase with excavations carried out inside existing buildings. It is usually not possibleto use machinery owing to the restricted space, and the resulting hand digging ismuch more expensive than digging by machine. Moreover, the removal of spoil needsto be done in small quantities, which also adds to the cost. These factors may needspecial mention in the specification.

Although special mention need not be made of getting materials and goods into anexisting building for use in the works, this may require the temporary removal and

replacement of doors, windows, staircases or walls, and such work needs to bespecified. Inserting a new steel beam between existing walls and building its ends intothose walls implies the cutting of very deep pockets, since the beam will be longerthan the distance between the walls, and this also needs special mention.

Dimensions

Existing works in old buildings will not necessarily be of the same dimensions as newwork, eg walls may not be precisely brick multiples. Odd thicknesses in a wall

plastered both sides may indicate the presence of some material other than brick, orthe wall may be composed of battens and lath and plaster on a brick core. Avoid

being dogmatic about existing work obscured by plaster or other finish. In pricingwork the onus is always on the builder to ascertain the precise nature of the existing,and the risk of making a wrong decision is quite properly left to him. Remember alsothat old plaster will most likely be thicker than that now to be executed, and inextending existing plastered surfaces additional coats or dubbing out may be requiredin order to achieve the same thickness. In any case, dubbing out should always bespecified with plastering on existing unplastered walls to mask the surfaceundulations almost always present in such surfaces.

Security

Safeguarding the existing buildings against unauthorised entry and preventingworkmen straying into parts of the building in which they have no business to be alsorequire clauses in the specification.




List of work items

Before drafting a specification clauses for alteration work, it is useful to make a list ofitems of work that are to be included. The following examples indicate the likelyscope of work included in two typical alteration items. These notes will then besuitably amplified to form the eventual clause.

Closing up an existing doorway internally

Remove door and frame etc and credit

Remove threshold paving

Brick up opening

Cut tooth and bond to jambs

Pin and wedge up to soffit

Plaster and decorate both sides

Make out skirtings both sides.

Forming a new doorway internally

Take off skirtings both sides and set aside

Uphold and cut opening

Provide and insert lintel over

Face up jambs each side

Level up threshold

New door, frame and architraves

Make good plaster and decorations both sides

Make out skirtings and return into reveals

Make out flooring in opening.

A typical specification for alterations work covering major works required in

converting an existing building is included in Appendix B.




Appendix AExtract from a specification for a new building












SPECIFICATION

of works required to be done and materials to be usedin the erection and completion of

A PRIVATE HOUSE

at

ENTRANCE TO TOWERS ESTATE,LONDON ROAD, HORSLEY, SURREY

for

JOHN SMITH ESQUIRE

A D Bord FRIBAChartered Architect999 High StreetGuildfordSurrey




SPECIFICATION OF WORKS

required to be done and materials to be used in the erection and completion of ahouse at the entrance of the Towers Estate, London Road, Horsley, Surrey for JohnSmith Esquire, under the superintendence and to the satisfaction of

A D Bord Esq FRIBAChartered Architect999 High StreetGuildford Surrey

Drawing numbers Spec 3/1, 2 and 3

Date

PRELIMINARIES

Scope of the works

1. The works comprise the erection and completion of a brick-built house two storeyshigh on the north-western side of the private road at the entrance to the estate fromDowns Road as shown upon the block plan. There is a single-storey annexe on thenorthern end, the main roof is pitched and tiled, the walls brick faced, the groundfloors are of solid construction and the first floor is of timber construction.

Access to site

2. As the private road shown on the site plan is in continuous use, access for theseworks is to be by means of a new opening to be made in the fence on the north sideof the new house (see later clause).

Form of contract

3. The Contractor will be required to sign the current JCT standard form of buildingcontract, private edition (without quantities), a copy of which may be viewed at theArchitect’s office by appointment. The Conditions of Contract therein contained areto be read in conjunction with and as a part of this Specification.

Submission of the Contractor’s estimate will be deemed to imply his familiaritywith the requirements of these Conditions of Contract.

The Appendix of such Agreement will be completed as follows

Clause

17 Defects liability period 6 months

23 Date for possession Immediately after signing the contract

1.3 Date for completion To be stated by contractor on Form ofTender

24Liquidated and ascertaineddamages

At the rate of £...... per day

28 Period of delay(a) Clause 22(b) Any other reason

3 months1 month




35 Prime cost sums for which thecontractor desires to tender

................................................................

................................................................

.................................................................

30 Period of interim certificates Each calendar month

30 Period of final measurement andvaluation

6 months

Relative to Clause 5 of the Agreement, the contract drawings will be

No 1 Site plan – Scale 1 : 100 No 2 Elevation and sections – Scale 1 : 100 No 3 Floor plans – Scale 1 : 100

In respect of fire insurance, Clause 22A of the Agreement will be retained in theContract.

Contractor to visit site

4. Before tendering, the Contractor should visit the site and satisfy himself as to thelocal conditions, the accessibility of the site, the full extent and character of theoperation, the nature of the ground, the supply and conditions affecting labour andthe execution of the Contract generally, as no claim on the grounds of want ofknowledge in such respects will be entertained.

5. Trial holes, two in number, have been made on the site and remain open forinspection. Particulars of the materials thereby exposed are available to theContractor on request, but no guarantee is given of the accuracy of the particulars orthat the nature of the material found in the excavations will be similar to thoseshown in the completion of these works.

Access, footways etc

6. Allow for opening up the existing fence at the rear of the proposed new garage asnecessary for access to these works, keep closed when not in use and reinstate fence

so disturbed at the completion of these works.

7. Include the provisional sum of £x for taking up footway paving and for reinstatingthe same on completion of the works. This work is to be executed to the satisfactionof the local authority.

Temporary roads

8. Provide any temporary roads and pathways as may be necessary for the proper performance of the contract and clear away and make good on completion.

Hoardings

9. Construct and maintain around the site, where not already fenced, a suitable chain-link enclosure not less than 3m high, with posts and gates as may be required for thesecurity of the works, and clear away and make good at completion or whendirected.

10. The Contractor shall not display any advertisements on the hoarding other than hisfirm’s name board if he so wishes, neither shall he permit any other advertisementsto be displayed without the written authority of the Architect.




Plant, tools and scaffolding

11. Provide, erect and maintain all necessary hoists, scaffolding, mechanical equipment,shoring, plant etc of all descriptions required for the due completion of the works,and allow subcontractors free use of same, and remove all as and when required orwhen directed by the Architect.

Water and temporary plumbing

12. Provide water for the whole of the works and pay charges for the same and for providing, installing and subsequently removing necessary temporary pipe work,storage cisterns, taps etc.

Watching and lighting

13. Provide all necessary day and night watching, lighting, barriers etc that may berequired for the protection of the works and the safety of the Public.

Casing and protection

14. Protect the works from injury and make good any damage caused by frost, wet,carelessness or otherwise.

15. Provide all necessary tarpaulins, dust sheets or any other approved and effectivemeans to exclude weather from the premises during execution of any work to roofslopes, flat or vertical surfaces and remove on completion.

16. Provide, fix and maintain all necessary temporary coverings as required forfloorings, pavings, exposed angles, joinery etc and remove on completion and makegood any damage sustained or caused.

Temporary sheds etc

17. Provide all necessary sheds and storage spaces for materials and for workshops thatmay be required, maintain and clear away on completion.

18. Provide all necessary latrine and other facilities for the use of the workpeople asrequired by the Code of Welfare Conditions for the Building Industry, maintain indecent condition and clear away on completion.

19. Pay any rates that may be legally demandable by the local authority.

Site office

20. Provide suitable offices on site for the use of the foreman, provide telephone and pay rates and remove on completion.

Temporary lighting and power

21. Provide wire for and connect all electric lighting and power for the execution of theworks, allow all subcontractors free use of same and pay any charges for current.

Attendance

22. Provide for attendance of trade upon trade and do all cutting away and making goodas may be required to complete the works.




Materials generally

23. All goods and materials are to be of British manufacture and to be of the qualitydescribed. The name of the manufacturing firm and samples of the materials as may

be asked for are to be submitted to the Architect; any subsequent deliveries whichare not equal to the approved sample will be rejected.

24. All goods and materials so specified are to comply in all respects with therequirements of the latest British Standard.

Pulling down and arisings

25. Take down the small sheds etc on the site, grub up any foundations and removerubbish and old materials except such old bricks or other material as may beapproved by the Architect for reuse after cleaning in the foundations of the new

building or for hardcore.

Sand and aggregate in foundation

26. Should suitable sand or aggregate be found in the excavations and the Contractor isallowed to use the same in the works, he will be required to pay the Employer forthe same at the full market value thereof.

Frost and inclement weather

27. No concrete, mortar or plaster is to be used when the temperature is below 6ºC andnew work is to be protected at night when frost has been forecast or may reasonably

be anticipated.

28. A maximum and minimum recording thermometer is to be provided during thecourse of these works and fixed in a fair position; a daily record of readings taken at0900 is to be kept in the foreman’s office.

Statutory insurance

29. In addition to such insurances as are mentioned in the Form of Agreement, theContractor is to pay all premiums and Employer’s contribution in respect ofstatutory national insurances, supplementary pensions, guaranteed week, holidayswith pay, redundancy schemes, etc as may be in force at the date of tendering.

Expediting the work

30. If the Contractor for the purpose of expediting the work or for any other reason shallarrange for the working of overtime or night work so that the work may becompleted in every respect and ready for use within the time stated, then any extracosts thereby incurred shall be at his own expense, unless such overtime has beenspecifically authorised by the Architect in writing.

Drying out

31. Provide for approximately 150 hours (actual operating time) of a portable spaceheater having an airflow of . . . m3/per hr with fuel and attendance over a period ofnot more than four consecutive weeks to be used in a manner to be agreed with theArchitect for drying out the building.




Rubbish and cleaning on completion

32. Gather up and clear away all rubbish as it accumulates during the progress of theworks and on completion.

33. On completion, scrub all floors, pavings, staircases etc, clean out gutters, pipe headsand gullies, clean windows on both sides and leave the premises clean, sound and

watertight.

Notices and fees

34. Give all notices to local authorities as required.

Contingencies

35. Include the provisional sum of £x for contingent or unforeseen works to beexpended as directed by the Architect or deducted in part or in whole if not required.

EXCAVATION

Levels

1. The levels preceded by the letters OGL on the site plan are those existing otherwisethe figures shown are finished levels. If the Contractor is not satisfied as to theaccuracy of these levels he must give written notice thereof to the Architect beforeany excavations are commenced, otherwise no claim in respect of inaccuracy oflevels will be entertained.

Earthwork support

2. Provide all necessary earthwork support and keep excavations free from water. TheContractor will be required to cut out to a square section any trench sides that mayhave been allowed to fall in through insufficient support or any bottom which has

been excavated below the correct level or which may have become soft through

standing under water. Any such extra excavation must be filled in solid withconcrete, quality D as later described, at the expense of the Contractor.

Clear away hedges and shrubs

3. Cut down hedges, shrubs and trees as indicated, grub up roots and any oldfoundations and disused drains that may be met with and remove from site.

Turf and vegetable soil

4. Carefully cut, roll turf and stack where directed on site for collection by Employer’srepresentative. Excavate over surface average 100mm deep and wheel topsoil anddeposit where directed on site. Only vegetable soil shall be used in restoration oflevels around the buildings, any surplus being spread where directed.

Trenches

5. Excavate for foundations to the lengths, widths and depths shown upon thedrawings. All excavations are to be approved by the Architect and local authorityand no concrete is to be laid therein until such bottoms have been so inspected andapproved. Should any extra excavation be ordered by the Architect dimensions ofthe same must be taken and agreed with the Architect whilst still open.




Level and ram bottoms

6. Level and consolidate bottoms of all excavations in preparation for concrete andhardcore.

Filling in trenches

7. Fill in selected excavated material externally around walls in 300mm layers and

consolidate.

Disposal of surplus excavated material

8. Clear away surplus excavated material from site.

Hardcore

9. The hardcore, which is to be of clean dry brick or concrete rubble broken to pass a75mm ring, is to be laid not less than 150mm thick in preparation for solid floorsand external pavings and thoroughly consolidated. Blind surfaces of hardcore withfine ash or sand to fill in all interstices and roll and level off in preparation forconcrete.

CONCRETE

Portland cement

1. The cement shall be normal setting Portland cement to comply with BS 12 and is to be stored in a dry place and used fresh.

Sand

2. The sand shall be clean angular pit or river sand, free from impurities, washed andscreened if required.

Aggregate

3. The aggregates for concrete shall be in accordance with BS 882. Aggregates shall beregularly graded in size to pass a mesh of the size indicated in the table following.

Water

4. The water for concrete shall be clean and fresh as from the mains.

Proportions

5. The proportions of all materials shall be accurately measured and mixed either on aclean surface or in a batch mixer in the following proportions. Where a crushingstrength is stated, 150mm test cubes are to be prepared as often as directed by theArchitect.

Nominal mix by volume Preliminary testcrushing strength

(28 days)Quality Cement Sand Aggregate Gauge N/m

A 1 – 6 38mm all-in graded 15B 1 3 6 10 and 19mm 22C 1 2 4 10 and 19mm 28D 1 – 8 38mm all-in graded 12

2




Consistency

6. The consistency of the concrete shall be uniform and of even colour. Consistencyshall be regulated from time to time as the work proceeds by means of the slumptest and a 50mm slump should be regarded as desirable.

Depositing

7. Concrete shall be conveyed in pneumatic tyred barrows and deposited as quickly as possible after mixing. Work should proceed continuously. In restarted work thesurface of the joint shall be lapped or hacked, brushed and slurried with cement andsand 1:1. Concrete which has commenced to set shall not be used or reworked, butif allowed to set hard may be broken up and used as aggregate in concrete quality Donly.

8. No concrete is to be tipped or thrown from a height exceeding 1.5m.

9. Concrete shall be carefully placed into the formwork or moulds and tamped throughand around bar or fabric reinforcement.

10. Where excavations are timbered, the timbering shall be drawn immediately theconcrete is deposited so that the latter may be rammed close against the face of theexcavation.

Curing

11. Keep concrete damp for at least one week and protect from frost or too rapid drying by covering with sacking, polythene sheeting etc. No traffic of any description orloading on concrete shall be permitted until it is set and hard enough to resistdamage by such loading.

Reinforcement

12. Steel bar reinforcement for lintels etc is to comply with BS 785, of mild steel,

cleaned free of all rust, scale, oil etc, cut to lengths, bent and hooked at ends andsecured in position with concrete spacers and annealed soft iron binding wire.

13. Fabric shall be of high tensile steel and is to comply with BS 1221 and be of thereference number indicated. Adjacent sheets shall be lapped at least 150mm at sidesand ends and secured as last specified.

Formwork

14. The formwork is to be constructed in a substantial manner, properly braced. Allsurfaces are to be coated with mould oil before concrete is placed and to bethoroughly cleaned before reuse.

Concrete in foundations

15. Fill into trenches concrete quality A, 225mm deep and 300mm wider than the bottom course of brickwork, as foundations to all walls (other than those half a brickthick) and chimney breasts and level off to receive brickwork.

Surface concrete and concrete sub-floors

16. Lay over the whole site of the building within the internal walls and at the levelsshown on the drawings a bed 100mm thick of concrete quality B finished level.




17. Below half brick walls the 100mm bed is to be thickened to 250mm for a width of450mm as the foundation.

18. Lay similar concrete bed 150mm thick on hardcore to falls where pavement crossingis indicated on the drawings and tamp surface to form non-slip corrugations.

Cavity walls

19. Fill in cavity of hollow walls up to finished ground level with concrete quality C.

Concrete lintels

20. Form concrete quality C lintels over all door, chimney and window openings unlessotherwise specified, precast or cast in situ as is convenient. The lintels are to be atleast 300mm longer than the span of the opening and of a width equal to thethickness of the wall except where reduced by a brick arch and generally 150mmdeep. Each lintel is to be reinforced with one 10mm diameter mild steel bar forevery half brick in the width of the soffit and with 40mm cover.

21. Lintels to openings 1.2m wide and over are to be 225mm deep and reinforced asdescribed but with rods 12mm diameter.

Hearths

22. Screed hearths and back hearths with cement and same 1:3 trowelled smooth.

Solid floors

23. On a damp-proof membrane formed with 1 000 gauge polythene lapped 75mm at joints lay a 50mm screed of cement and sand 1:3 to form solid floors and finish toreceive the pavings specified later.

Fabric reinforcement

24. Allow provisionally for reinforcing the whole of the surface concrete with high

tensile steel fabric to comply with BS 1221 reference 109, placed 40mm from thetop of the concrete with an additional strip of similar fabric 500mm wide placed beneath all half brick walls.

25. Allow provisionally for a further layer of 500 gauge polythene sheet as before to belaid over blinded hardcore beds and before surface concrete is deposited to protectreinforcement.




BRICKWORK AND BLOCKWORK

Cement

1. The Portland cement is to be as specified in ‘Concrete’.

Sand

2. The sand is to be clean, washed, angular sand obtained from a local pit and free ofclay, vegetable, animal or other deleterious matter.

Lime

3. The lime is to be hydrated lime to comply with BS 890 and mixed with sand in the proportions specified hereafter, the water added and the mixture then allowed tomellow for at least eight hours before use.

Mortar

4. All mortar is to be mixed on a clean concrete or other hard dense surface or in anappropriate machine. Mortar which has once become set may not be knocked-upand used.

5. All proportions are by volume and are based upon dry sand; an appropriateallowance is to be made for the bulking of damp sand.

Cement mortar

6. Cement mortar for use in work below damp-proof course, for the top twelve coursesof chimney stacks and for all partitions is to be mixed in the proportions of one partof Portland cement to four parts of sand.

Gauged mortar

7. The mortar generally is to be gauged mortar composed of one part of cement, one part of lime and six parts of sand, and the composition is to be thoroughly mixed

until of smooth consistency and even colour.

Common bricks

8. Brickwork below damp-proof course is to be built with local wirecut bricks, hard,well burnt, true in shape and free from stones, lime and other flaws.

9. Brickwork above damp-proof course is to be of Fletton bricks grooved or keyedwhere to receive plastering and bricks are to be wetted before use.

Facing bricks

10. Facing bricks are to be selected, sand-faced, machine-made Surrey multi-colouredfacing bricks, PC £x per thousand, delivered to site packed in straw and the

Contractor is to unload, handle and stack with the straw packing so far as isreasonably practicable.

Hollow clay blocks

11. The hollow clay partition blocks are to be in accordance with BS 1190 Section 1and of the keyed type where required for plastering.

Wall ties

12. The wall ties are to be galvanised mild steel vertical twist type not less than 150mmlong as BS 1243.




Appendix BExample specification for works of alteration

and repair

SPECIFICATION

of works required to be done and materialsto be used in

THE CONVERSION INTO SEVEN LIVING UNITS

of

THE HALE STREET STORES,HALE STREET, EASTLEY, THAME

for

MESSRS SIMPSON & SONS LTD

John Silver FRICSChartered Surveyor




HALE STREET STORES £ p

PRELIMINARIES

Situation and scope of the works

1. The works are situated in the buildings known as the Hale

Street Stores, Hale Street, Eastley, Thame, on the westernside of Hale Street between its junctions with Smithers Landand Seven Mile Lane. Access at all reasonable times is byarrangement with the owners or their surveyor, John SilverFRICS of ‘Flints’, Eastley, Thame, telephone 871449.

2. The works comprise the renovation of the existing buildingsand their conversion into seven self-contained living units,and include general layout, access road and landscaping.

Contract

1. For the mutual protection of building Owner and Contractor,

the successful Contractor will be required to enter into aformal written contract using the Joint Contracts Tribunal’sStandard Form of Building Contract (without quantities) andContractors tendering should ensure that they are familiarwith the provisions of that form of contract.

Tender

1. The Contractor is to submit his tender for the works on theform provided using the envelope provided for the return ofhis tender to the Surveyor.

2. The Contractor’s tender is solely to be based on this

specification and the accompanying drawings, none of whichare to be altered in any way.

3. In arriving at his tender figure the Contractor is to insert a price in this specification against each item if he deems thatitem to attract a price. Items not priced will be deemed tohave had their value – if any – distributed amongst otheritems in this specification, and no subsequent claims forextra payment on account of items in the specification not

priced will be allowed to rank. All tenders must beaccompanied by a detailed build-up of the kind outlinedabove, and lump sum tenders without such detailed pricingwill not be accepted.

Continued £





Continued

4. The Contractor’s tender is to include inter alia for thefollowing:

All labour, materials, workmanship, plant, tools, equipment,scaffolding and any other thing required for the due

performance of the works.

All insurances, whether statutorily required or otherwise,graduated pensions contributions and the like.

Workmen’s compensation, third party, fire, theft and burglary insurance.

Note: The existing premises will be insured against fire bythe Owner. The Contractor is to insure the new works andhis plant, tools and equipment.

Contributions in respect of holidays with pay schemes,training schemes, guaranteed time and the like.

Office overheads, supervision and profit.

Transport of labour, materials, plant and all other things to,from and about the site.

Indemnifying the Employer against all claims of whatsoevernature arising out of the due performance of the works andinsuring against all such claims.

All other factors likely to affect the amount of the tender

whether specifically mentioned herein or not.

5. The Employer does not bind himself to accept the lowest norany tender, nor to pay the cost of preparing tenders.

Conduct of the works

1. The Contractor is to visit the site to ascertain for himself thespace for working and storage of materials, and all otherfactors likely to affect the amount of his tender. He is toobtain for himself the necessary dimensions required for thesetting out of the works or the ordering of materials and noclaim arising from a plea of ignorance of site conditions will

be entertained.

2. The works are to be carried out with care and diligence,expeditiously and continuously once the successfulContractor has gained possession of the site, and to preventhis own workmen from trespassing on those parts of the sitenot the subject of these works or on adjoining property.

3. The Contractor is to take all reasonable steps to exclude thetrespass of unauthorised persons on the site and to preventhis own workmen from trespassing on those parts of the sitenot the subject of these works or on adjoining property.

Continued £





Continued


1. All materials and workmanship are to be of the best of their

respective kinds or as described herein. The relevant BSSpecification for any material will be regarded as theminimum quality which will be acceptable.

Water etc

1. Mains water and electricity are connected, and theContractor will be allowed to use these supplies for theworks. He is to pay all charges and allow for providing alltemporary plumbing and wiring.

2. The Contractor is to provide all necessary temporary screens,tarpaulins and the like to exclude the weather and

unauthorised intruders during the course of the works and tolimit nuisance arising from dust, and is to erect, maintain,alter, adapt and subsequently remove and clear away thesame on completion.

3. The Contractor is to allow for covering and protecting allnew and existing work as may be necessary to keep the samefree of injury arising from whatsoever cause during thecourse of the works, and is to make good at his own expenseany damage or other consequence arising from neglect ofthis provision.

PC and provisional sums

1. Where PC or provisional sums are included in thisspecification they will be regarded as being subject toomission from the final account, and replaced therein by theascertained cost of the work involved. In the case of PCsums, Contractor’s profit and attendance or fixing only willalso be subject to adjustment on a pro rata basis.

2. Where provisional sums are included in this specification,they are intended to be inclusive of all profit and otherfactors and require no amendment or addition by theContractor.

3. Where PC sums are included in this specification, theContractor is to add if he so wishes for profit and attendingon specialists where the work is described as to be executed

by specialists, and for profit and fixing where the work isdescribed as to be supplied only.

Continued £





Continued

Generally

1. The submission by the Contractor of a tender will be deemed

to imply that he has complied with or is willing to complywith all the requirements of this specification and of theform of contract described. No claim arising from a plea ofignorance of site circumstances, drawing content,specification or contract requirements will be allowed torank.

Contingencies

1. Include the provisional sum of £x for contingent orunforeseen works to be expended or deducted in whole or in

part as directed by the Surveyor.

Continued £





Flat No 1 (Ground floor, left-hand side)

Generally

1. The submission by the Contractor of a tender will be deemed

to imply that he has complied with or is willing to complywith all the requirements of this specification and of theform of contract described. No claim arising from a plea ofignorance of site circumstances, drawing content,specification or contract requirements will be allowed torank.

Contingencies

1. Include the provisional sum of £x for contingent orunforeseen works to be expended or deducted in whole or in

part as directed by the Surveyor.

Stripping out etc

1. Strip out and clear away the existing matchboard lining towalls and ceiling in the main store room, the site of futureflat No 1.

2. Strip out and clear away the existing timber stairs risinginside this main storeroom.

3. Remove and clear away the existing double entrance doorsleading from road into the main store, complete with frame.

4. Cut away the lower projection of brickwork to the chimney breast, make good as required and build up the fireplaceopening with brickwork, incorporating a 225 × 225mm

plaster louvred air grating (general replastering taken

elsewhere).

5. Take down the partition and door therein leading from mainstoreroom to adjoining shop and clear away.

6. Take up existing woodblock flooring over part of the mainstoreroom and clear away.

7. Strip out all existing electric wiring, lighting points, gas pipes and the like and clear away in the main storeroom.

8. Remove and clear away the small rear window to the mainstoreroom complete with burglar bars.

9. In the single-storey back addition to the main storeroom,remove and clear away all existing partitions and doorstherein.

10. Similarly in this area remove all existing external doors andwindows and clear away.

11. Similarly in this area remove and clear away the existingWC suite and plumbing thereto including shutting off ofsupplies and draining down as required.

12. Similarly in this area, take down the existing brick wall andcorner chimney breast between the two apartments togetherwith any remaining stack in catslide roof space over.

13. Hack down all remnants of wall and ceiling plastering inmain storeroom and single-storey back addition, rake out

joints of brickwork as key and prepare for replasteringseparately described.

Continued £





Continued

Flat No 1 continued

14. Demolish the existing two-storey garage adjoining main

storeroom, credit useful arrissing and clear all away, andallow for temporarily closing door from garage roof spaceinto first floor.

Filling openings in existing walls

1. Prepare for and fill in the opening left after removal ofexisting double entrance doors to main storeroom with 9"

brickwork finished with facing bricks externally to matchexisting and properly cut, toothed and bonded to existing,including forming and necessary concrete foundationthereto.

2. Similarly fill in the entrance door opening and adjoining

window opening in the single-storey back addition to mainstoreroom.

Enlarge existing openings

1. Enlarge existing rear window openings in single-storey backaddition adjacent to the main storeroom to suit new casementwindows later described including forming any necessarylintels or brick arches over.

2. Similarly enlarge window opening in rear right-hand cornerof main storeroom.

New wall between main store and shop

1. Excavate as required for and form new strip concretefoundation at suitable depth, and prepare for and constructnew 215mm brick wall in common brickwork to fill existingopening between main store and adjoining shop, properlycut, toothed and bonded to existing and pinned up to existingconstruction cover.

Form new openings

1. In front right-hand wall of main store, cut and form newwindow opening in existing external wall to accommodatenew window of size indicated, quoin up jambs, form suitable

brick arch over to match existing.2. Similarly form two new window openings in left-hand wall

of main storeroom.

3. Similarly form two new entrance doors opening in this samewall. (Note: New windows and doors are described later.)

Continued £





Continued

Flat No 1 continued

Sandwich floor main store area

1. On existing solid floor surface, make up levels withconsolidated hardcore as may be required and blind withsand. Construct thereon new solid concrete sandwich floorcomprising 25mm cement and sand screed on 100 mmconcrete bed incorporating polythene sheet damp-proofmembrane.

Ditto back addition

1. Over the area of the back addition, excavate as required, andconstruct similar solid concrete sandwich floor comprising25mm screed and 100mm concrete bed as before laid on100mm bed of consolidated hardcore.

2. Beneath all internal block partitions shown, thicken theabove concrete floor to a total thickness of 300mm for awidth of 400mm as partition foundation.

Main store columns and beams

1. Support as required and take out the existing cast-ironcolumns supporting ceiling beams in main storeroom.

2. Form suitable foundations and construct two 225 × 225mm brick columns as indicated to pick up existing and newceiling beams.

3. Provide two new 150 × 75mm rolled steel beam underexisting where indicated on the drawing, pinned up one endon new brick column and build into external wall at otherend including reinforced concrete spreader beam in wall.Wedge and pin up to soffit over.

Internal partitions in main store

1. Build the new 100mm load-bearing blockwork internal partitions in the main storeroom forming new living spaces,

as indicated on the drawings, cut, tooth and bond to existingwalls, and wedge and pin up to soffit over. Form all dooropenings therein for doors hereinafter described.

Opening in rear wall of main store giving to new kitchen andbathroom

1. Support as required and cut away to form new opening inexternal wall of main store giving to new kitchen and

bathroom in back addition, and provide new reinforcedconcrete lintels where shown dotted on the drawing, carriedon existing walls and new stair-enclosing walls.

Continued £





Continued

Flat No 1 continued

Stair walls

1. Excavate as required in back addition and form new foundationsfor and construct new 225mm brick stair-enclosing walls cut,toothed and bonded to existing and carried up to first floor (see on).Form new entrance door opening in rear wall of back addition fordoor hereinafter described, with suitable lintel or arch over.

New concrete stair

1. Within the new stair enclosure, construct reinforced concreteaccess stair as indicated on the typical section, with hardwoodfacings to treads and risers.

Damp-proof courses

1. Provide asbestos-based bituminous felt horizontal damp-proofcourses in all new brick walls and fillings to openings.

2. Include the PC sum of £x for Rentokil electro-osmotic damp-proofcourse system to be installed complete by Messrs Rentokil (Damp-Proofing) Ltd and add for profit and attending on the specialistinstallers.

Windows

1. Provide and install new purpose-made wrought softwood casement

windows all to match existing, glazed as appropriate, includingforming faced brick and plastered external and internal reveals andinternal window boards, in the following positions

New living roomBedroom 1Bedroom 2BathroomKitchen

– – – – –

two windowsone windowone windowone windowone window

Overhaul windows

1. Overhaul and repair as required the two existing windows in front

wall of main storeroom and provide double glazing thereto.

External doors

1. Provide new external entrance doors and frames to entrances toFlats 1 and 4 (ground and first floors) complete with locks andfastenings, all to match in all respects the existing entrance door atright-hand end of front elevation.

Continued £





Continued

Flat No 1 continued

Internal doors

1. Provide new hardboard faced flush doors and suitablelinings, complete with locks and fastenings, to all roomentrances, understair cupboard and larder cupboard (sevendoors and linings in all).

Plastering etc

1. Provide 25 × 75mm plain softwood skirtings throughout allrooms.

2. Prepare for and plaster all new and existing wall surfacesthroughout including understair cupboard space.

3. Prepare for and line soffit of existing first floor over area ofmain storeroom only, with fire line wall board, battening and

glass fibre insulation, all as indicated on the typical sectiondrawing and continue the lining around new and existingceiling beams.

Decorations

1. Prepare and paint two coats gloss paint on all externalwoodwork of doors and windows.

2. Similarly paint all internal woodwork of doors and windows,skirtings etc.

3. Prepare and paint two coats emulsion paint on all wall andceiling surfaces.

Electrical

1. Include the PC sum of £x for electrical installation executedcomplete by a specialist firm and add for profit and attendingon the specialists.

Sanitary fittings

1. Include the PC sum of £x for sanitary fittings includingkitchen cupboards and worktops, supplied and delivered tosite by a specialist firm, and add for unloading, assemblingand fixing only the following (services and wastes andconnections thereto separately specified):

Low level WC suitePedestal washbasin1 650mm pressed steel bath with riser panelsShower cabinet complete with mixer valveKitchen sink unitTwo floor units complete with continuous worktopTwo wall cupboard units.

Plumbing, drainage and heating

Note: These services are separately specified later.

Continued £





Flat No 2 (Ground floor centre)

Stripping out etc

1. Demolish and clear away the existing shopfront completewith walls, glazed framing and doors and flat roof over.

2. Demolish and clear away all internal partitions in the frontand rear shop.

3. Strip out and clear away the existing timber stairs and galleryat first floor level in rear shop.

4. Strip out the matchboard lining to the existing tack room forfull ground and first floor height.

5. Strip out all matchboard linings to walls and ceiling

elsewhere in front and rear shop.

6. Take up and clear away the existing hollow timber groundfloor in the shop area complete with boarding joists and wall

plates and clear away sleeper walls.

7. Strip out all existing electric wiring, lighting points, gas points, gas and water pipes and the like, and clear away.

8. Demolish and clear away the chimney breast in the existingtack room (demolishing first floor ditto and chimney stack

separately specified).

9. Take out and clear away the existing rear entrance door andadjoining window.

10. Take out and clear away the entrance door and frame toextreme rear store.

11. Demolish and clear away the chimney breast in the rearkitchen including taking out the existing domestic boilertherein, shutting down and draining down supplies asrequired (demolishing first floor ditto and chimney stack

separately specified). Demolish and clear away the right-hand wall of the extreme rear store in readiness for extensionof party/fire baffle wall.

12. Demolish and clear away the right-hand wall of the existingtack room (demolishing first floor continuation of this wallseparately specified).

Continued £





Continued

Flat No 2 (Ground floor centre)

13. Hack down all remnants of wall and ceiling plasteringthroughout the front and rear shops and extreme rear store,

rake out joints of brickwork as key and prepare forreplastering (separately described). Take out all timberlacings in existing brick walls and build up chases with

brickwork.

New front wall

1. Excavate for and form new foundations, and construct newhollow wall in place of existing columns and beamsincluding removing these same and pinning up to existingconstruction at first floor level. Form all necessary door andwindow openings therein and cut, tooth and bond to existingwalls as required.

Filling openings in existing walls

1. Prepare for and fill in opening left after removal of tack roomground-floor window with 225mm brickwork finishedexternally with facing bricks to match existing and properlycut, toothed and bonded to existing.

2. Similarly fill in door opening leading from rear shop to right-hand end of premises.

3. Similarly fill in tack room doorway and doorway intoextreme rear store.

Rear wall to new kitchen and living room

1. Demolish as required, excavate for and form newfoundations where necessary, and construct new brickmullions at rear of new kitchen and living room, formingkitchen and living-room window openings, making goodexisting remaining and cut, tooth and bond to existing and

pin up to existing first floor construction as required.

New extension of party/fire baffle wall in existing rear kitchen

1. Excavate as required and form new foundations, and

construct extension of existing party/fire baffle wall to formnew right-hand wall of Flat 2 bathroom, including cutting,toothing and bonding to existing.

Continued £





Continued

Flat No 2 continued

Form new openings

1. In rear wall of extreme rear store, cut and form two newwindow openings as indicated, quoin up jambs.

2. In left-hand wall of this store, similarly form new dooropening.

3. In wall between this store and new living room, similarlyform new door opening.

4. Cut away right-hand end of front wall of tack room to suitnew stair enclosure.

Sandwich floor

1. In manner all as previously described to Flat No 1 excavatefor and form new sandwich floor over the whole area of Flat

No 2.

New first floor

1. Over the area at present occupied by the rear stairs andgallery, prepare for and construct new timber joisted and

boarded first floor in continuation of existing.

Stair walls

1. In manner all as before described to Flat No 1 formfoundations and construct new 225mm brick stair-enclosingwalls.

New concrete stair

1. In manner all as before described for Flat No 1 constructreinforced concrete access stair.

Internal partitions

1. In manner all as before described to Flat No 1 construct newload-bearing blockwork internal partitions and form new

door openings therein.

Damp-proof courses

1. In manner all as before described to Flat No 1 providehorizontal damp-proof courses in all new brick walls andfillings to openings.

2. Include the PC sum of £x for electro-osmotic damp-proofingto existing walls, as described to Flat No 1.

Continued £





Continued

Flat No 2 continued

Windows

1. Provide purpose-made windows, all as described to Flat No1, in the following positions:

Rear bathroomRear WCRear lobby to bathroom and WCRear kitchenRear living roomTwo front bedrooms

External doors

1. In manner as before described to Flat No 1 provide externalentrance doors and frames to Flats 2 and 5 (ground and firstfloors).

Internal doors

1. In manner as before described to Flat No 1 provide new flushdoors and linings to all rooms, under-stair cupboard andlarder (six in all).

2. In similar manner and hung on ball-bearing overhead gear, provide sliding door to rear lobby.

3. Similarly provide pair of sliding doors to give access fromliving room to kitchen.

Plastering etc

1. Provide new 25 × 75mm skirtings throughout as beforedescribed.

2. Prepare for and plaster all new and existing wall surfacesthroughout including under-stair cupboard.

3. Prepare for and line soffit of first floor with fire line wall board etc all as described to Flat No 1.

Decorations

1. Prepare and paint two coats gloss paint on all wall andceiling surfaces.

2. Similarly paint all internal woodwork of doors, windows,skirtings and the like.

3. Prepare and paint two coats emulsion paint on all wall andceiling surfaces.

Continued £





Continued

Flat No 2 continued

Electrical

1. Include the PC sum of £x for electrical installation executedcomplete by a specialist firm and add for profit and attendingon specialists.

Sanitary fittings

1. Include the PC sum of £x for sanitary fittings, includingkitchen cupboards and worktops, supplied and delivered tosite by a specialist firm, and add for profit, unloading,assembling and fixing only the following fittings (servicesand wastes and connections thereto separately described):

Low level WC suitePedestal washbasin1 650mm pressed steel bath with riser panelsShower cabinet complete with mixer valveKitchen sink unitTwo floor units complete with continuous worktopTwo wall cupboard units.

Plumbing, drainage and heating

Note: These services are separately specified later herein.

Continued £




Note

The items included for Flats 3–6 inclusive and a maisonette in the original specificationfollow a similar pattern and the sections including these have been omitted.





Plumbing and hot water services throughout

Flats 1 and 4, 2 and 5, 3 and 6

Pricing

Note: The following works comprise the cold and hot water servicesto all new flats (not maisonette) and the resulting total will bedivided equally between the six flats.

Rising mains

1. Include the PC sum £x for new connections to company’swater main (three connections in all) and add for profit andattending on water company’s workmen.

2. Excavate etc as required and provide and lay three 12mmdiameter service pipes and rising mains taken up througheach vertical pair of flats to supply new storage cisterns; tee

off as required and run 12mm supply to kitchen sink of eachflat and connect thereto.

Storage

1. In the roof or attic space over each vertical pair of flats,construct suitable timber staging and provide and install two250 litre fibreglass cold water storage cisterns and two‘Osma’ fibreglass hot water storage cylinders, all suitablyinsulated (six cisterns and six cylinders in all).

Water heating

1. Provide and install Twimerser dual element electricimmersion heater in each cylinder (six in all). (Provision ofelectricity points included in PC sums previously included

per flat.)

Interconnections

1. Between each cistern and accompanying cylinder, provideexpansion pipe and cold water supply pipe with stopcock. Toeach cistern provide ball valve and overflow pipe (six sets ofexpansion pipes, cold supply pipes, ball valves andoverflows).

Cold down services

1. From each cold water storage cistern run 18mm diameterdown service with stopcock and diminishing as required to

provide cold water supply to all sanitary fittings exceptkitchen sink and connect to fittings.

Continued £





Continued

Flats 1 and 4, 2 and 5, 3 and 6 continued

Hot down services

1. Similarly from each hot water storage cylinder run 18mmdiameter down service with stopcock and diminishing asrequired to provide hot water supply to all sanitary fittingsincluding kitchen sink and connect to fittings.

Lagging and casing

1. Lag all hot water down service pipes where concealed and all pipework in roof and attic spaces. ( Note that vertical pipework is to be encased in the soil and vent pipe casingsspecified hereinafter and are not to be run vertically downthrough floors outside such casings.)

TOTAL £

Carried to individual flat collections:ONE SIXTH OF TOTAL £





Plumbing and hot water services

Maisonette

Rising main

1. Connect to existing rising main entry in existing kitchen andrun as required, including teeing off to provide supply to newkitchen sink; continue to maisonette bedroom 1 to supplynew storage cistern and connect thereto.

Storage

1. In maisonette bedroom 1 provide suitable timber staging andinstall cold water storage cistern and hot water storagecylinder all as before described complete withinterconnecting pipework as before described.

2. Provide Twimerser electric immersion heater as before

described.

3. Form timber-framed and hardboard-covered encasing tostorage cistern and cylinder, with removable access panel.

Cold down service

1. Connect to the cold water storage cistern and run 18 mmdown service with stopcock and diminishing as required to

provide cold water supply to new bathroom sanitary fittingsand connect thereto.

Hot down service

1. Similarly from hot water storage cylinder expansion pipe run18 mm down service with stopcock and diminishing asrequired to provide hot water supply to all new bathroomfittings and kitchen sink and connect thereto.

Lagging

1. Lag all hidden pipework.

Carried to maisonette collection £





Wastes

Flats 1 and 4, 2 and 5, 3 and 6

Pricing

Note that the following works comprise the wastes for all new flats(not maisonette) and the resulting total will be divided equally

between the six flats.

Main soil waste and ventilating pipes and casing

1. Construct three vertical soil waste and ventilating pipe stacksin the positions indicated on the drawings carried fromground-level drain inlet connections vertically up through the

building to penetrate roofs and terminate with suitablegrating, and provide all necessary branch connections forindividual wastes from the various fittings; connect to draininlets and mount to walls on suitable brackets or holderbats.

2. Form fire-resisting casing around each stack, of soft asbestoswallboard on suitable timber framing and with removable

panels to provide access to branch connections and/orclearing eyes.

Individual wastes

1. Ground floor

Run individual waste pipes from fittings to connect asfollows (pipe sizes to be: sinks – 38mm, basins – 32mm,

baths – 38mm, showers – 38mm).

To back inlet gullies:

To soil stack branch:

Flat 1 sink, bath, basin, showerFlat 2 dittoFlat 3 ditto

Flat 1 WCFlat 2 WCFlat 3 WC

2. First floors

Run individual waste pipes from fittings to connect asfollows (sizes as above).

To soil stack branch: All fittings.

TOTAL £

Carried to individual flat collection:ONE SIXTH OF TOTAL £





Wastes

Maisonette

Individual wastes

1. Connect WC to drain inlet; run in waste piping of sizes previously described to connect bath, basin, shower andkitchen sink to back inlet gully connections.

Carried to maisonette collection £





Attic spaces

Generally

1. Remove and clear away the existing cold water storagecistern in the main attic together with all pipework.

2. Remove existing loading door giving into rear of attic andclose up opening in manner to match adjacent walling, andleave as if no door had existed.

3. Brush treat the whole of the attic flooring with approvedwoodworm fluid.

4. Make good existing wall and sloping ceiling plastering asrequired.

THE BUILDING EXTERNALLY

Front

1. Remove existing name board over main store entrance andmake out tiling as required and leave as if no nameboard hadexisted.

2. Overhaul and make good as required the verge tiling to theroof over main store.

3. Alter and adapt as required the existing rainwater pipes (onedischarging into garage guttering and one discharging in

angle of main store and shopfront), to descend vertically anddischarge on to paving.

4. Form new window sill to first floor window in return of mainstore to shopfront.

5. Remove cobble and other paving in front of existingshopfront, lift cellar flap stone outside main store and fill invoid under if any.

6. Scaffold as required and deeply rake out joints and repoint all

brickwork to front elevations, in cement lime mortar tomatch existing.

Left hand

1. Similarly rake out joints and repoint all brickwork to left-hand end (main store).

Rear

1. Strip existing tiling from remains of catslide roof left afterconstruction of new first floor flat bathroom etc, felt, rebattenand rehang existing tiling and make good. Shorten existingground-floor eaves guttering as required.

Continued £





Attic spaces

Continued

2. Similarly strip and retile rear slope only of roof over groundfloor rear shop.

3. Form new window sills to existing window to first floor flatover main store lighting kitchen, and to the window lightingstaircase.

4. Remove waste pipe from rear of ground floor shop livingquarters kitchen and make good, and alter and adapt existingrainwater pipe in this area including forming new soakawayand underground drain thereto.

5. Build up window opening lighting outbuilding at rear ofmaisonette preparatory to formation of new maisonette

bathroom.

6. Scaffold as required and repoint all brickwork to rearelevations and returns thereto as before described.

Right-hand end

1. Strip and retile as before described the whole of the pitchedroof slope facing ‘The Harp’.

2. Strip and retile on new battening the tile-hung portion of theright-hand end chimney breast near the front of the building.

3. Scaffold as required and repoint all brickwork to the right-hand elevations as before described.

Stacks

1. Remove existing chimney pots and close flues with slates incement and provide ventilating gratings to all flues in side ofstacks; rake out joints and repoint all chimney stacks.

SUNDRIES

Woodworm

1. Include the provisional sum of £x for treatment ofwoodworm infestation discovered during the execution of theworks as a whole.

Sundry matters

1. Include the provisional sum of £x for removing burglar bars,stripping out sundry cupboards and other fittings, and sundryfireplace surrounds, including building up redundantfireplace openings and providing ventilating gratings thereto.

Carried to collection for attics and externally £





External works

Demolition and site clearance

1. Clear away all rubbish, overgrowth and other matter at present on the site, together with existing fences and the like.

2. Demolish all existing outbuildings, sheds and the like andclear away all arisings.

3. Break up and clear away all paved areas, paths, drives andthe like.

Lay-by and access road and apron

1. Excavate to lines and levels, falls and cross falls as requiredfor new lay-by, access road and apron.

2. Construct lay-by, access road and apron of 225mm bed ofhardcore suitably rolled and compacted and shaped to fallsand cross falls, with 150mm bed of concrete reinforced withsuitable mesh reinforcement, laid in bays with expansion

joints and steel bar dowels across joints and form precastconcrete kerbing thereto all as indicated on the site layoutdrawing. Provide two rows of granite setts at junction withthe public road.

Garage base

1. Provide and lay 150mm concrete base to garages on suitablehardcore bed.

Road drainage

1. Provide 300mm diameter road gulleys with cast-iron gratingsall set in 150mm concrete including all necessary excavationand connecting to drains.

2. Construct four surface water manholes where indicated onthe drawing, with 150mm concrete base and 225mm bricksides complete with all necessary channels and step irons.

3. Excavate as required and lay surface water drains with

150mm diameter flexible jointed stoneware piping laid on150mm concrete bed 450mm wide and connect to manholes.

4. Construct suitable surface water soakaway in rear part of siteand connect new drainage thereto.

Continued £





Continued

External works (continued)

Garages

1. Provide seven precast concrete single garages with up andover doors and assemble and erect on site on concrete bed

previously described, complete with eaves guttering andrainwater pipe discharging to road gully adjacent.

Paved areas

1. Construct paved areas as indicated using 600 × 600 × 50mm precast concrete flags laid on 75mm sand bed on 100mmconsolidated hardcore, with 12mm open joints and suitable

precast concrete edging, including all circular cutting thereto,and laying to suitable falls.

Lawns and beds

1. Excavate as required and form surfaces, grade, prepare andturf. Form flowerbeds where indicated, surfaced with 225mmselected vegetable soil and cultivated.

Trees and shrubs

1. Provide and plant trees and shrubs where indicated on thedrawing.

Windmills

1. Provide clothes drying windmills and sockets and set in

position (seven in all).

Boundary fence

1. Provide along rear boundary close boarded riven oak fencingon sawn oak posts with gravel board and capping. (Note: Garages form part boundary.)

2. Along Hale Street, where garage demolished, prepare for andconstruct 225mm facing brick boundary wall on suitablefoundations, seven feet high with gate piers, and hangthereon existing wrought-iron gate, previously removed andset aside, as pedestrian access.

Notices

1. Include the provisional sum of £x for various notice boardsand signs about the site.

To Collection £




HALE STREET STORES

COLLECTIONS AND SUMMARY

Collections

Preliminaries Specification page –

–

–

TOTAL of preliminaries £

1/7th of above total carried below to each flat and maisonette £

Attics externally and sundries Specification page –

–

–

TOTAL of attics etc £


External works Specification page –

–

–

TOTAL of external works £





HALE STREET STORES Summary £ p £ p

Flat No 1 General work – Specification page – – –

Plumbing etc –

Wastes –Drainage –1/7th preliminaries –1/7th attics etc –

1/7th external works –

£


Plumbing etc –Wastes –Drainage –

1/7th preliminaries –1/7th attics etc –

1/7th external works –£


Plumbing etc –Wastes –Drainage –1/7th preliminaries –1/7th attics etc –

1/7th external works – £


Plumbing etc –Wastes –Drainage –1/7th preliminaries –1/7th attics etc –

1/7th external works –£

Continued £




HALE STREET STORES Summary £ p £ p Continued £


Plumbing etc –Wastes –Drainage –1/7th preliminaries –1/7th attics etc –1/7th external works –

£


Plumbing etc –Wastes –

Drainage –1/7th preliminaries –1/7th attics etc –1/7th external works –

£

aisonette General work – Specification page – – –

Plumbing etc –Wastes –Drainage –1/7th preliminaries –

1/7th attics etc –1/7th external works –£

GRAND TOTAL COST OF WORKS £

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