Plaster Work, Renders and Screeds.pdf

Sultanate of Oman Ministry of Transport and Communications Development of Muscat International Airport

Main Contract 1 Project Specification

Architectural

Plaster Work, Renders and Screeds

General Specification

April 2009

Sultanate of Oman Ministry of Transport and Communications Development of Muscat International Airport

Main Contract 1 Project Specification

Architectural

Plaster Work, Renders and Screeds

General Specification

April 2009

Report no. SE-000-A-11450

Issue no. C01

Date of issue 14.04.2009

Prepared CYRA /SMLY/PKSI

Checked CYRA/TCWE

Approved OBL

Main Contract 1 Project Specification Architectural – Plaster Work, Renders and Screeds General Specification

P:\61400\3_DOC\10_Tender_Doc\01_SE\CRN_26_MC 1_Civil\Final Doc\2009.04.14_Issued for Construction\3.3_Specs\Building\Architectural\SE-000-A-11450_C01_Plaster Work, Renders and Screeds.doc

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Table of Contents

1 General 2

1.1 Introduction 2

1.2 Related Documents 2

1.3 Codes and Standards 2

1.4 Submittals 3

1.5 Warranty / Guarantee 4

1.6 Project Conditions/Coordination 4

1.7 Manufacturers 5

2 Products 6

2.1 Materials 6

3 Execution 9

3.1 Examination 9

3.2 Preparation 9

3.3 Installation 11

3.4 Application 12

3.5 Workmanship 17

3.6 Cleaning and Protection 18

4 Quality Control 19

4.1 Delivery, Storage and Handling 19

4.2 Mock-ups 19

5 Testing and Commissioning 20

6 Revision Log 21



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1 General

1.1 Introduction

A. This section specifies standard material and workmanship for internal and

external plaster work, including proprietary render and floor screeds as

indicated in the contract drawings or schedule of finishes, or as required in

completion of the Works.

1.2 Related Documents

A. This section to be read in conjunction with Employer’s requirements and

general provision of contract, including General, Supplementary and

Special Conditions of Contract Documents.

1.3 Codes and Standards

A. All materials, workmanship and testing shall be in accordance with the

following documents, in their latest revisions. This is not exhaustive and

contractor shall verify the listing and supplement with the latest applicable

document or documents.

1. Comply with the requirements of the reference standards noted herein,

except where more stringent requirements are listed herein or

otherwise required by the Contract Documents.

2. Where US material or reference standards are specified or indicated,

equivalent British Standards (BS), any other European Standards are

acceptable.

3. Conform to the requirements of the following British Standards and

Codes of Practice where applicable:-

a) BS 5385-2: 2006 Wall and floor tiling. Code of Practice.

Design and installation of external

ceramic and mosaic wall tiling in normal

conditions.



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b) BS 6213:2000 Selection of construction sealants. Guide

c) BS 8481:2006 Design, preparation and application of

internal gypsum, cement and lime

plastering system.

d) BS EN 934-3:2003 Admixtures for concrete, mortar and

grout. Admixtures for masonry mortar.

Definitions, requirements, conformity,

marking and labelling.

e) BS EN 998-1:2003 Specification for mortar for masonry.

Rendering and plastering mortar.

f) BS EN 998-2:2003 Specification for mortar for masonry.

Masonry mortar.

g) BS EN 1008:2002 Mixing water for concreting.

h) BS EN 12878:1999 Pigments for the colouring of building

materials based on cement and/or lime.

i) BS EN 13139:2002 Aggregates for mortar.

j) BS EN 13279 Part 1 &

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Gypsum binders and gypsum plasters.

k) BS EN 13501-1:2007 Fire classification of construction

products and building elements.

l) BS EN 13658-1: 2005

and BS EN 13658-2:

2005

Metal lath and bead. Definitions,

requirements and test methods, internal

plastering. External rendering.

m) BS EN 13914 –

1,2:2005

Design, preparation and application of

external rendering and internal plastering.

1.4 Submittals

1.4.1 Technical Data

A. In the case of proprietary products submit comprehensive technical

literature for the Engineer’s prior approval. When so requested by the

Engineer, prepare samples of plasterwork and/or render for his approval.



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1.4.2 Shop Drawings

A. Provide Shop drawings as required by Engineer, shall depict actual site

measurements.

1.4.3 Samples

A. Submit 600mm x 600mm samples of each cement plaster finish specified

herein, with cutaway corners showing lath, scratch, brown, and finish

coats, including finish texture specified or selected by the Engineer.

1.4.4 Method Statement

A. Method statement shall include method of application, health and safety

management, testing methods, required relative humidity and temperature

level and control systems, possible risk associated with the execution

works and precautions, site control system and any other additional

requirements as advised by the Engineer for the execution of works/

B. Methodology: where detailed methodology has been specified. the

contractor may submit an alternative methodology based on their

experience, for the Engineer’s approval.

C. Method statement shall be approved by the Engineer prior to

commencement of the works.

1.4.5 Material Certificates

A. Submit certificate signed by manufacturer for each kind of plaster

aggregate certifying that materials comply with the requirements specified

herein.

1.4.6 Maintenance Data

A. For each type of plasterwork to include in maintenance manuals.

1.5 Warranty / Guarantee

A. Unless otherwise stated elsewhere, Engineer shall receive a written

guarantee against defects due to improper material and installation for a

period of 10 years from the date of Employers taking over of the works or

sections.

1.6 Project Conditions/Coordination

A. Internal Plasterwork: Maintain room temperatures at least 48 hours before

plaster application, and continuously during and after application.



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1. Avoid conditions that result in plaster drying out during curing period.

Distribute heat evenly; prevent concentrated or uneven heat on plaster.

2. Ventilate building spaces as required to remove water in excess of that

required for hydrating plaster in a manner that prevents drafts of air

from contacting surfaces during plaster application and until plaster is

dry.

B. External Plasterwork:

1. Apply and cure plaster to prevent plaster drying out during curing

period. Use procedures required by climatic conditions, including

moist curing, providing coverings, and providing barriers to deflect

sunlight and wind.

C. Factory-Prepared Finishes: Comply with manufacturer's written

recommendations for environmental conditions for applying finishes.

D. Check and verify the positioning and fixing of all conduits or other similar

items which are to be concealed by either plaster, render or screed. Ensure

that such items requiring testing have been satisfactorily tested and

approved by the Engineer before plasterwork is commenced.

1.7 Manufacturers

A. Manufacturer to be accredited and registered under BS EN ISO 9001.



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2 Products

2.1 Materials

2.1.1 Cement Sand Plaster/Render/Screed

A. Cement

1. Ordinary Portland cement complying with BS 197

B. Sand for plastering/rendering

1. Comply with BS EN 13139:2002. Sand to be hard, clean and free

from deleterious matter likely to affect adversely the hardening,

strength, durability of appearance of the plaster.

C. Aggregate

1. Fine aggregate (including sand) and coarse aggregate for screeds.

Comply with BS EN 13139:2002.

D. Water

1. Clean potable water free from harmful matter and from any unusual

proportion of dissolved salts. Seawater or brackish water shall not be

used.

E. Plasticizers

1. Plasticizer: Liquid admix to improve workability, control suction and

minimize crazing. Use to manufacturer’s instructions. Recommended

in preference to lime for hot climates. Mortar plasticizers shall comply

with BS EN 934 part 3.

2. Lime: In certain climatic conditions it may be necessary to use Lime.

Hydra lime is ideal. Otherwise use high-quality wet slaked line of

Chalk Lime to BS EN 459 part 1 to 3



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F. Metal lath, corner/stop beads etc

1. Proprietary expanded aluminium or galvanised steel lath and

associated accessories with hot dip galvanised zinc coating and

recommended separation materials.

2. Steel lath to comply with BS EN 13658 part 1 & 2

a) Diamond – Mesh lath

b) Flat Rib lath – Rib depth of not more than 3.1mm

G. Bonding Agent

1. Bonding agents, where required, shall be of type recommended by the

manufacturer of the plaster material and approved by the Engineer.

2. Comply with BS EN 934-3

H. Fibre for Base Coat

1. Alkaline-resistant glass or polypropylene fibers, 13 mm long, free of

contaminants, manufactured for use in Portland cement plaster.

I. Acrylic Filler

1. Modified acrylic filler containing not less than 55% solids. Type as

recommended by manufacturer of plaster material or approved by

Engineer.

J. Fasteners

1. Fasteners for Attaching Metal Lath to Substrates: Comply with BS

1202-1 & BS EN 13658 part 1 & 2.

K. Acrylic-Based Finish Coatings

1. Factory-mixed acrylic-emulsion coating systems formulated with

colourfast mineral pigments and fine aggregates; for use over Portland

cement plaster base coats. Include manufacturer's recommended

primers and sealing topcoats for acrylic-based finishes.

2. Colour: [As selected by Engineer from manufacturer’s full range]

L. Zinc and Zinc-Coated (Galvanized) Accessories

1. General: Coordinate depth of trim and accessories with thicknesses

and number of plaster coats required.



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2. Casing Beads: Fabricated from [zinc] [or] [zinc-coated (galvanized)

steel] with expanded flanges, in depth required to suit plaster bases

indicated and flange length required to suit applications indicated.

a) Square-edge style; use unless otherwise indicated.

b) Bull-nose style, radius 19.1 mm minimum; use at locations

indicated on Drawings.

3. Control Joints: Fabricated from zinc/zinc-coated (galvanized) steel;

one-piece-type, folded pair of un-perforated screeds in M-shaped

configuration; with perforated flanges and removable protective tape

on plaster face of control joint.

4. Plastic Trim: Fabricated from high-impact PVC.

2.1.2 Proprietary Ready-Mixed Finish-Coat Plaster

A. Mill-mixed Portland cement aggregates, colouring agents, and proprietary

ingredients to BS 998-2.

1. Colour: As selected by Engineer from manufacturer's full range.



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3 Execution

3.1 Examination

A. Masonry Substrates to be checked as follows:

1. Concrete Block work: to be of good alignment within allowable

tolerances and have completely filled mortar

joints.

2. Clay Bricks: same as above.

3. Gypsum Plasterboard

Partitions

same as above

4. Concrete: Remove traces of mould oil. Provision of a

mechanical key must be provided for a smooth

surface as per good building practice e.g. spatter

dash coat of sand, cement and SBR applied by

brush or spray to leave a rough raised texture.

Complete coverage of the surface is essential.

5. For other substrates please refer to the render manufacture for

preparation instructions.

6. Do not proceed with work until unsatisfactory conditions have been

corrected.

3.2 Preparation

3.2.1 Preparation for plastering/rendering

A. Remove ridges and other imperfections from shuttered concrete surfaces

before cleaning down.

B. Roughen smooth surfaces to ensure a keyed bond to plasterwork.

C. All substrates to be in good condition, clean, dust – free and with no traces

of loose material that may impair adhesion of the render.



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D. Excessive flatness defects in the substrate must be corrected at least 48

hours before application by using an undercoat or dubbing out coat of

sand/cement render.

E. The substrate must be wetted the day before application from bottom to

top. On the day of application the wall to be rendered shall be wetted again

in the same way, without surplus water.

F. Protect adjacent work from soiling, spattering, moisture deterioration, and

other harmful effects caused by plastering.

G. Prepare solid-plaster bases that are smooth or that do not have the suction

capability required to bond with plaster according to BS 8481:2006 and BS

EN 13914-2:2006.

H. Coordination with Sprayed Fire-Resistive Materials:

1. Before sprayed fire-resistive materials are applied, attach offset

anchor plates or ceiling runners (tracks) to surfaces indicated to

receive sprayed fire-resistive materials.

2. After sprayed fire-resistive materials are applied, remove them only to

extent necessary for installation of plaster assemblies and without

reducing the fire-resistive material thickness to less than that required

to obtain fire-resistance rating indicated. Protect remaining fire-

resistive materials from damage.

3.2.2 Preparation for Floor Screeds

A. All existing work and approaches shall be protected with boards, dust

sheets or other suitable means.

B. All bases shall be thoroughly cleaned to remove all dirt, dust, rust and oil.

C. Hardened in-situ concrete where screed is to be bonded:

1. Shortly before laying screed, the concrete base shall be thoroughly

hacked to remove all laitance and to expose as much cleanly coarse

aggregate as possible. All loose concrete shall be washed away and

the surface left clean.

2. 24 hours before laying screed, the base shall be wetted and surplus

water removed. Provide suitable covering to prevent evaporation.

3. Neat cement slurry shall be brushed onto the surface 20 minutes

before laying screed, or a bonding agent shall be applied in

accordance with the manufacturer’s recommendations.



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3.3 Installation

3.3.1 Installing Metal Lath

A. Expanded-Metal Lath

1. Install according to BS EN 13658-1:2005 and BS EN 13858-2:2005

B. Arch forms

1. Where shown on the contract drawings, incorporate preformed

specialist galvanised expanded metal arch forms from approved

supplier.

C. All grooves indicated on drawings, except for the fair-face concrete

cladding units, shall be made from metal plaster stop as detailed on

contract drawings.

D. All chases in wall shall be covered by metal lathing prior to rendering.

3.3.2 Installing Accessories

A. Comply with referenced installation standards for provision and location of

plaster accessories of type indicated. Miter accessories at corners except

where factory pre-fabricated corners and intersections are specified or

indicated on the drawings; install with tight joints and in alignment. Attach

accessories securely to plaster bases to hold accessories in place and in

alignment during plastering.

B. Control Joints: Install at locations indicated or, if not indicated, at locations

complying with the following criteria and approved by Engineer.

1. Where an expansion or contraction joint occurs in surface of

construction directly behind plaster membrane.

2. Distance between control joints: Not to exceed 9m centres.

3. Where plaster panel sizes or dimensions change, extend joints full

width or height of plaster membrane.

C. Metal Lath at Intersection of differing substrates:

1. Where plaster is to be applied continuously across differing substrates,

such as intersection of masonry and concrete beams or columns,

install a minimum 300mm wide strip of metal lath with polyethylene

isolation membrane across the intersection.

2. Where a small width of differing material less than 300mm wide is to

be bridged, install lath in sufficient width to completely cover the

bridged material, plus 150mm wide on each side.



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3. Stretch lath taught and secure along each edge with washers and shot-

fired pins, nails, or screws spaced 100mm o.c. Screws shall be fixed

into plugs in pre-drilled holes.

4. Coat all fasteners and cut edges of metal lath with bituminous paint.

5. Install zinc-coated lath and accessories to be completely embedded in

and covered by plaster of sufficient depth to prevent corrosion. Do not

install metal lath where grooves in the plaster are indicated on the

drawings.

3.4 Application

3.4.1 Plaster/render and floor screed mix proportions

A. All materials used for plasterwork shall be proportioned by volume by

means of gauge boxes as follows or as indicated in contract

drawings/schedules.

1. Internal plastering 1:6 (cement: sand)

2. Floor Screed

a) For Floor Screeds less than 50mm thick 1:3 (Cement: Fine

Aggregate)

b) For Floor Screeds of 50mm and greater thickness 1:1 ½:3

(Cement: Fine Aggregate: Coarse Aggregate [max size 10mm])

3.4.2 Mixing of plaster/render/screed

A. Proportion materials in parts by volume per sum of cementitious materials

and aggregates. Adjust mix proportions within limits specified to attain

workability.

B. Mix plaster in mechanical mixer. Accurately measure ingredients by

volume or weight as specified; use bonding agent as admixture as directed;

mix until evenly distributed and uniform in colour. Do not use materials

that are froze, cracked, lumpy, or partially set.

C. Clean mixer of all set or hardened material before loading a new batch.

Keep tools and equipment clean.

D. Mixing sequence and time shall conform to materials manufacturer’s

instructions.



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3.4.3 Application of plaster/render

A. Unless otherwise indicated on contract drawings the thickness of plaster/

render to be as follows:

1. Internal walls: Total 15mm min.

2. Internal ceilings, soffits: Total 12mm thick

B. Plaster application on masonry or concrete:

1. Clean substrates of all dirt, dust, and loose particles, and on concrete,

form or mould oils. If dubbing out is required, complete well in

advance of the basecoat or undercoat. Use mix at least as strong as the

base or undercoat, but not stronger than the substrate. Apply in two

coats if the required thickness exceeds 16mm; no coat shall be more

than 13mm thick.

2. Prepare concrete surfaces by one of the following methods:

a) Hacking by hand or mechanical means to remove all laitance and

to roughen the entire surface to a depth of 3mm, exposing the

aggregate.

b) Application of a uniform spatter coat consisting of one part

cement and two parts coarse sand, mixed with sufficient water to

produce thick slurry consistency. Apply to damp substrate with a

trowel or scoop to produce a thin coating with roughcast, uneven

finish. Dampen periodically to prevent rapid loss of moisture and

permit to dry slowly and harden prior to commencement of

plaster application.

3. Spray substrate uniformly with water prior to application of base coat.

Apply bonding agent only if recommended by plaster materials

manufacturer or directed by Engineer.

4. Apply first (scratch) base coat with sufficient material and pressure to

form good bond to masonry base. Apply to approximately 8mm

thickness and cross-take to provide good key for second coat. After

setting, damp-cure for not less than 48 hours prior to application of

second coat.

5. Apply second (brown) base coat over moistened scratch coat with

sufficient pressure to key into scratches. Build out to within 3mm of

screeds and straighten to a true surface with rod and darsy without use

of additional water. Leave rough to receive finish coat. After setting,

damp-cure for not less than 48 hours prior to application of finish

coat.

6. Apply finish coat to well-moistened basecoat, scratching in

thoroughly and immediately double back to a true, even surface, flush



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with screeds. Finish to match approved mock-up. Do not use water in

floating or finishing. Fog-spray surface with water for at least three

days (longer if required by climatic conditions) after setting.

7. Provide a V-cut or quirk at the junction of plaster and door frames.

Cut shall be neat and consistent in depth and width throughout its

entire length. Do not allow plaster to spill onto the frame.

C. Plaster Application on Metal Lath:

1. Install first (scratch) basecoat with sufficient material and pressure to

force plaster through metal lath and form a good key. Apply to

approximately 9mm thickness and cross-rake to provide good key for

brown coat. After setting, damp-cure for not less than 48 hours prior

to application of brown coat.

2. Apply second (brown) basecoat over moistened scratch coat with

sufficient pressure to key into scratches. Build out to within 3mm of

screeds and straighten to a true surface with rod and darsy without use

of additional water. Leave rough to receive finish coat. After setting,

damp-cure for not less than 48 hours prior to application of finish

coat.

3. Apply finish coat to well-moistened brown-coat, scratching in

thoroughly and immediately double back to a true, even surface. Do

not use water in floating or finishing. Fog-spray with water for at least

three days (longer if required by climatic conditions) after setting.

4. Total thickness of plaster shall be not less than 20mm, measured from

face of lath.

3.4.4 Concealed Interior Plasterwork

A. Where plaster application will be concealed behind built-in cabinets,

similar furnishings, and equipment, apply finish coat.

B. Where plaster application will be concealed above suspended ceilings and

in similar locations, finish coat may be omitted.

C. Where plaster application will be used as a base for adhesive application of

tile and similar finishes, finish coat may be omitted.

3.4.5 Mixing and Application of Plasterwork:

A. By trained operatives approved by the manufacturer only and to

manufacturer’s instructions.

B. Mixing – always use the same quantity of water per bag and comply with

the same mixing time per mix.



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C. The finish is to be ‘scraped’ with ashlar details as per Engineer’s

instructions and contractor’s shop drawings.

D. No plaster angle beads or stops to be used.

E. Choice and allocation of colours to be approved by the Engineer.

3.4.6 Mixing and Application of Floor Screeds

A. The surface of concrete beds and slabs, which are to receive screeds shall

be hosed down in a green state and brushed with a stiff brush to remove

laitance and form a key for the screed. Before laying the screed, the surface

of the concrete shall be thoroughly cleaned and a coat of cement grout

(1:1) applied. Where required to have a trowelled finish, the screed shall be

finished with a steel trowel to a hard level and smooth surface. Screeds

shall be generally finished to receive the paving or surface treatment and

shall be free of trowel marks, checks or other blemishes, maximum

permissible deflection +/13 mm under straight edge.

B. The mixture of cement and sand screed shall be added with sufficient

water to produce a workable mixture. Maximum slump shall be 2 inches.

C. The cement and sand screed shall be laid after walls and partitions are

built.

D. Screeds are to be maintained in a moist condition for at least three days by

covering with a layer of sacking, canvas, hessian, straw mats or similar

absorbent material kept constantly wet. Screeds shall be protected from

damage until the screed is sufficiently dry to receive the specified finish.

Screeds which are to be left exposed shall be laid on alternate bays not

exceeding 15 sqm. Screed thickness shall be as indicated on plans.

E. Polythene sheet 200 gauge.

F. Sand shall be to BS EN 13139:2002

G. Aerated lightweight concrete mixes shall be in accordance with the

manufacturer’s recommendations to a density of 400 kg/cu.m.

H. Bonding agent shall be a type recommended by a cement manufacturer.

I. Screeds must be laid by specialist operatives skilled in laying screeds

3.4.7 Laying of Floor Screeds

A. Lay screeds in alternate bays of maximum area 12 Sq.m. and maximum

dimension 5m. Butt joints to coincide as near as possible with joints in

base.



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B. Square and plain joints shall be formed between screed bays or strips,

closely abutted and level, and thoroughly compacted at edges.

C. Movement joints shall be formed in screed over movement joints in base,

using jointing material placed to full depth and finished flush surface.

D. Screeds less than 80mm thick to be laid in one layer. For screeds over

80mm thickness lay in two layers, the first being not less than 20mm thick

and the second being placed immediately after compaction of the first

layer.

E. Compaction of screeds to be carried out by approved mechanical means.

Areas inaccessible to such equipment may be steel trowel compacted and

floated manually.

F. The material shall be thoroughly compacted for the full depth, without

bringing any excessive laitance to the surface removing any which does

appear. The surface shall not be wetted.

G. Bring surface to a smooth uniform finish free from defects and blemishes

to provide a satisfactory surface to receive the floor finish required.

H. Finishing

1. Surface of internal screeds shall be finished smooth with steel trowel

or power float to receive thin sheets or tiles.

2. Where cement and sand screeds are to receive terrazzo, clay or

ceramic tiles the screed shall be finished with a slightly rough finish to

accept the cement paste and tiles.

3. Surface of roof screed shall be finished with wood or other suitable

face float to give an even texture.

I. Check levels to ensure compliance with the requirement of the drawings.

Permitted tolerance will be 3mm in 3000mm in any direction.

J. In areas with floor gullies the screed must fall to the gully. No low spots

shall be left between drainage outlets.

K. Immediately after laying the surface shall be protected from wind draughts

and strong sunlight. The surface shall be covered as soon as it has

sufficiently hardened either with:

1. canvas, straw mats or a 50 mm layer of damp sand,

or

2. waterproof sheeting kept in close contact with the surface

and shall be left for not less than 7 days in normal weather conditions.



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L. Where different finishes are each side of a door opening, an aluminium

“T” section shall be screwed to the base to provide a dividing strip between

the different finishes.

M. All defective work in screeds shall be made good before applying finishes.

3.4.8 Curing of plaster

A. Allow adequate ventilation to remove excess moisture from the plaster.

B. Under no circumstances use water or membrane methods of curing.

C. By fine spray of clean water twice a day for 2 days following the day of

application.

3.4.9 Curing and Protection of Screeds

A. Protect finished screed surface from direct sun, rain and mechanical injury.

B. Do not allow screed surface to dry out till the expiration of a minimum

curing period of seven days. Do not allow traffic on surface during this

period.

3.4.10 Defects in plaster/render (Cutting and Patching)

A. Defective areas of plaster/render to be cut out to rectangular shape, the edges

undercut to form dovetail key and finished flush with the face of

surrounding plasterwork. Colour and texture must be maintained. Restore

cracks, dents and imperfections. Repair or replace work to eliminate

blisters, buckles, crazing and check cracking, dry outs, efflorescence,

sweat outs, and similar defects and where bond to substrate has failed.

3.4.11 Application of Acrylic Filler

A. On interior plaster areas indicated to be painted, allow plaster to fully cure

and apply specified filler using spatula, filling knife, or trowel to a dry film

coating thickness of 300 microns. Allow to thoroughly dry, then sand as

required to provide a smooth surface with texture and appearance similar

to gypsum drywall (plasterboard).

3.5 Workmanship

A. All plasterwork shall be executed in a neat and workman-like manner all to

the approval of the Engineer. Conform to the recommendations of BS EN

8481:2006 and BS EN 13914-2:2006.



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3.6 Cleaning and Protection

A. Application should be carried out in the shade where practicably possible.

The erection of hessian shade netting or a mobile shelter should be

considered. This shading should preferably be in position during the curing

period.

B. Remove temporary protection and enclosure of other work. Promptly

remove plaster from doorframes, windows, and other surfaces not

indicated to be plastered. Repair floors, walls, and other surfaces stained,

marred, or otherwise damaged during plastering.



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4 Quality Control

4.1 Delivery, Storage and Handling

A. Store materials inside under cover and keep them dry and protected against

damage from weather, direct sunlight, surface contamination, corrosion,

construction traffic, and other causes.

B. All branded materials are to be delivered to the site in their original

packages bearing the trade names of the material concerned.

C. Cement, hydrated lime and similar materials to be stored off the ground,

under cover and away from all possible source of damp.

D. Store sand under clean conditions to prevent contamination by soil or other

deleterious substances.

4.2 Mock-ups

A. Install mock-ups of at least 9 sq.m in surface area to demonstrate aesthetic

effects and set quality standards for materials and execution.

1. Install mock-ups for each type of finish indicated.

2. For interior plasterwork, simulate finished lighting conditions for

review of mock-ups.

3. Approved mock-ups may become part of the completed work if

undistributed at time of substantial completion.

B. Approved mock-ups may be incorporated into the finished work, where

directed by the Engineer.



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5 Testing and Commissioning

A. Fire-Test-Response Characteristics: For Portland cement plaster

assemblies with fire-resistance ratings, provide materials and construction

identical to those tested in assembly indicated according to BS EN 13501-1



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6 Revision Log

Date Issue Description

14.04.2009 C01 Issued for Construction

Date post:	19-Jan-2016
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