8.5 Painting and decorating
SITEWORK STANDARDS
| 8.5 - S1 | Sitework standards |
| 8.5 - S2 | Prefabricated components |
| 8.5 - S3 | Storage on site |
| 8.5 - S4 | Timing |
| 8.5 - S5 | Quality of finish |
| 8.5 - S6 | Wallpapering |
(a) meet the Technical Requirements
(b) take account of the design
(c) follow established good practice and workmanship
Sitework that complies with the design and the guidance below will be acceptable for painting and decorating.
PREFABRICATED COMPONENTS
Components to be painted, stained or sealed should have been primed (if to be painted) or given a first coat of stain or sealer before fixing.
Prefabricated joinery to be decorated should be supplied primed. Complete decoration should be carried out within the time specified by the manufacturer.
Components supplied untreated should have been stored under cover and be primed as soon as possible after delivery.
Where primer is damaged, surfaces should be re-primed.
STORAGE ON SITE
Items to be taken into account include:
(a) painting materials
Where it is necessary to store materials, the storage should ensure that the materials remain fit for use in the dwelling.
Water-borne paints, primers and stains should be protected against frost before use. Painting materials should not be used if they have been damaged by frost.
(b) prefabricated components
Where it is necessary to store components, the storage should ensure that they remain fit for use in the dwelling.
TIMING
Items to be taken into account include:
(a) external work
External paintwork should not be carried out under weather conditions which may adversely affect the completed work.
Surfaces should be free from frost before painting commences and while paint dries.
Coatings should not be applied to moist surfaces, nor when rain is expected before the paint surface has set.
(b) internal work
When decorating internal walls, cold surfaces may cause problems with water-borne paints, even though the air temperature may be above freezing.
Surfaces should be free from condensation before applying paint. Coatings, especially those which are oil-based, should not be applied until all moisture has evaporated from the surface. Internal paintwork should be left until the risk of dust and damage is minimal.
(c) staining
Staining should be carried out when the substrate is dry to ensure adequate dispersal and absorption.
QUALITY OF FINISH
Items to be taken into account include:
(a) painting on wood
SURFACE PREPARATION
Door and window furniture, sockets and light switches should be removed before painting to avoid over-painting and splashing.
Unsound wood, loose or highly resinous knots, etc should be cut out, replaced and made good.
Tool and machine marks and raised grain should be removed. Where a smooth surface is required, re-finish with glasspaper and fillers, as appropriate.
Nail holes, splits and other imperfections should be stopped. Sharp arrises should be rubbed down to ensure an even coating.
Surfaces to be painted should be free from dirt, dust and moisture.
All joinery delivered pre-primed to the site should meet the requirements given under PRIMING below.
Any surfaces showing deterioration of primer or seal coat should be rubbed down and a second coat applied.
Prefabricated joinery should have the first coat of paint or stain applied before fixing.
PRESERVATIVES
Before application, primer or paint finishes should be checked for compatibility with any timber preservatives that have been used.
Where appropriate, manufacturers' recommendations for selection and use of materials should be obtained and followed.
KNOTTING
All knots should be sealed using knotting applied by brush or in the case of joinery part of the priming process.
PRIMING
One full round coat of primer should be applied to all surfaces to be painted and to hidden surfaces of external woodwork.
Cut ends of external woodwork, rebates for glazing and backs of glazing beads should be primed.
UNDERCOAT AND GLOSS
Paint should not be thinned beyond the limits recommended by the manufacturer.
Unless an alternative recommendation is made by the manufacturer, the following should be applied:
- at least one undercoat (2 coats preferred),
and - one finishing coat.
The undercoat should provide a suitable base to ensure a satisfactory finishing coat. Additional undercoats or finishing coats are at the discretion of the Builder.
Each application should be a full round coat.
Surfaces should be lightly rubbed down between coats with glasspaper and each coat should be applied within one month of the application of the previous coat.
(b) staining and varnishing on wood
SURFACE PREPARATION
Before application, stains should be checked for compatibility with any timber preservatives that have been used. Stains should not be applied to door or window rebates to be glazed with linseed-oil putty.
Surfaces to be stained or varnished should be prepared to provide adequate adhesion and acceptable appearance.
APPLICATION
Low-build or high-build stain should be applied as recommended by the manufacturer to provide appropriate cover.
Varnish should be applied in at least three coats on interior surfaces. Exterior varnish (yacht or high gloss) should be applied in at least four coats. Surfaces should be sanded between coats.
(c) painting on metal
STRUCTURAL STEEL
Internal and external steel which has not been galvanized should be protected with at least two coats of zinc phosphate primer and a suitable decorative finish, where required.
Internal and external steel which has been galvanized to a rate of at least 460g/m2 is acceptable without further protection. Steel galvanized to a rate of less than 460g/m2 should be protected as steel which has not been galvanised.
Where steelwork is to be protected by intumescent paint for fire resistance, the manufacturer's recommendations should be followed.
GUTTERS
Insides of metal gutters (other than aluminium) should be painted with a suitable protective paint.
NON-FERROUS PIPEWORK
Copper pipes, etc should be painted with the normal decorative finishes.
(d) painting on other surfaces
EXTERNAL MASONRY AND RENDERING
Only materials specified should be used for external masonry or rendering.
Substrates should be clean and free from dust or loose deposits. Surfaces with varying suction may require stabilizing with a treatment recommended by the manufacturer.
PLASTER AND SKIM COAT ON PLASTERBOARD
Surfaces should be visibly sound and without powdering or crumbling.
All joints should be completed and any cracks, nail holes and surface imperfections filled. The surface should be rubbed down with glasspaper, if necessary, and dusted.
Surfaces require stabilizing, either with a coat of thinned paint or with a sealer recommended by the manufacturer.
Paint should then be applied in not less than two coats.
DRY LINING
A seal coat should be applied and surfaces prepared for decoration in accordance with manufacturers' recommendations.
BUILDING BOARD
Where painting is specified, surfaces should be primed or sealed and finished with at least two coats.
The first coat should be as recommended by the board manufacturer.
(e) surface finish
QUALITY OF COMPLETED WORK
All paintwork should be complete. Surfaces should be evenly coated and neither background nor undercoat should be visible.
Where brush marks, runs or abnormal roughness occur, work should be rubbed down and re-painted. Spilt, splashed or badly applied paint should be removed.
On completion, there should be no paintmarks on any surfaces not intended to be painted. On painted surfaces there should be no conspicuous runs or prominent brush marks. Ironmongery removed before painting should be re-fixed afterwards.
PROTECTION
Completed work should be protected against dirt and damage until the dwelling is handed over.
WALLPAPERING
Items to take into account include:
(a) surface preparation
Before any wallpapering is started, check that surfaces are dry and sufficiently even and smooth. Surfaces should be sized or sealed, if necessary.
To prevent stripping of the board lining paper, dry lining should be sized in accordance with manufacturers' recommendations.
Where proprietary coverings are used, any preparatory treatment recommended by the manufacturer should be applied.
(b) choice of adhesive
Adhesive of a type recommended by the wallpaper manufacturer should be used.
(c) workmanship
Wallpaper and coverings should be properly aligned and neatly fixed.
Electrical switch plates should be temporarily removed and the papering accurately trimmed so that it will tuck behind the switch plate on completion. Papers containing metal backings should not be tucked behind switch plates.
