Proper preparation of surfaces is a tedious and time-consuming job, but must not be skimped, otherwise old materials will ‘break through’ the new and spoil the redecor-ations. Also, if you prepare thoroughly the end result looks better, and redecorating the second time round will be much easier. Assemble the relevant tools, plus plenty of old lint-free cloths, at least I bucket, a sponge, detergent , sugar soap, a soft brush for dusting down, a broom, dustpan and brush, the vacuum cleaner if it has an attachment for sucking up dust, and lots of old newspapers. You may also need household cleaner, a scrubbing brush, white spirit, wire wool, several grades of glasspaper and ‘wet-and-dry’ — a silicone-carbide paper used both wet and dry — for rubbing down certain surfaces.
Complete the pre-preparation described in Order of work, including any structural work such as removing a fireplace or wall. Even if you have removed the floorcover-ings, exposing the floorboards, cover them completely with old newspapers, dust sheets or plastic sheeting; if you get decorating dirt and dust between the floorboards, this can show up later as ridges on a light-coloured carpet, and any lumps of paint sticking to the floorboards can quickly ‘work through’ a new floorcovering.
New walls and ceilings
If you are decorating a new house or a new extension make sure that the plaster is completely dry. Use a wide-bladed scraper to scrape off any ‘nibs’ of plaster, efflorescence or mortar. Fill cracks or holes with proprietary filler, leave to harden, then use glasspaper to rub down the surface until smooth. If the surface is porous, seal with a coat of stabilizing primer.
It is usual to paint newly-plastered walls with emulsion paint so they can ‘breathe’ -enabling a thorough drying out process to take place. If further efflorescence shows itself you can scrape it off- never wash it off. It also enables you to fill any settlement cracks before applying a new decorative wall treatment. The polyethylene type of wallcovering can be hung on new plaster as it is porous, but you cannot cope so easily with settlement cracks if you cover the wall.
New plasterboard or wallboard should be treated as new plaster; coat any nail or screw heads with metal primer. Seal the board with a plasterboard sealer or emulsion paint before wallpapering.
Rub down, working along the direction of the grain. Use a medium-grade abrasive paper dry, and finish with a fine-grade. Dust off. Apply one or two coats of patent knotting to any knots in the wood to seal the resin and prevent it ‘bleeding through’ the new paint. Fill any cracks, holes or open joints with cellulose filler if you plan to paint the wood, or wood stopper if you plan to use varnish. Leave to harden, rub down and dust off.
Prime the wood with an all-purpose primer if it is a softwood – use an aluminium primer on hard or resinous wood. Let the primer dry thoroughly, then apply the recommended undercoat. If you plan to varnish the wood, do not prime it, just wipe it over with a cloth dipped in white spirit.
Joinery such as window-frames may come already primed. Wash, if necessary, with detergent and water. Rub down with fine grade ‘wet-and-dry’. Patch-prime if there are any knocks or chips, then apply undercoat.
Make sure the surface is free from grease and oil — clean with wire wool dipped in white spirit if necessary. Prime with an all-purpose primer, or one appropriate for the metal you are dealing with. If the metal is already primed , patch-prime if it has become chipped. If the metal already shows signs of rusting rub down with emery cloth, fine abrasive paper or ‘wet-and-dry’ to remove all traces of rust before priming. NOTE: do not leave metalwork exposed for long, as rust quickly forms. Apply recommended undercoat without delay.
Previously painted walls and ceilings.
If the surface is flaky, first remove all loose material with a scraper, sand the bare areas and paint the patch so it is the same level as the rest of the wall or ‘feather off with proprietary filler.
If the paint used previously was emulsion, this normally only needs washing down with detergent and water. Always wash from the bottom of a wall, working upwards. If you start at the top you may get streaks down the wall which will show through new paint. Use household cleaning powder to remove any stubborn greasy marks. Wash with clean water and leave to dry. Then treat as for newly plastered walls.
If the surface was gloss-painted, treat as for emulsion but then remove the glossy surface by sanding down with medium-grade glasspaper or ‘wet-and-dry’.
If the surface was previously distempered test by wetting with a damp cloth: if a powdery substance comes away on the cloth you will have to remove all the old paint. Scrub, if necessary, with warm water and prime with stabilizing primer. If it is impossible to get all the old distemper off, you can cover the surface with lining paper before repainting or cross line before papering. NOTE: some water-based paints look like distemper, and were used on walls and ceilings in many older houses, but they don’t show on the cloth as a powdery substance and can be treated as emulsion paint.
Previously papered walls and ceilings.
Sometimes paper has been hung and then over-painted. This is much harder to remove than ordinary paper. If you want to repaint it rather than strip it off, you can do so providing it is in good repair arid firmly adhering to the wall. You can also paint over some existing wallcoverings , but again, only if they firmly adhere to the wall and are in good condition; do not overpaint if they have a gold, silver, or other metallic pattern as this usually ‘bleeds’ through new paint. Test a small area first to see if it can be over-painted, 92 and if not, it will all have to come off!
To strip ordinary wallpaper, first lightly score the surface then soak thoroughly with warm water to which a little washing-up liquid can be added – sponge or brush this on to the paper, or use one of those garden hand-held sprayers. Then leave for a few minutes, before you start scraping with the scraper, taking care not to dainage the wall plaster under the paper. Re-soak the paper as you work if it does not come off easily. Put the old paper straight into a plastic sack or cardboard carton as you work, since it will be sticky and get onto feet, hands etc. Go over the area a second time, to make sure that you have removed all traces of paper and old size or adhesive. Then wash the wall down thoroughly with clean water.
Fill any hairline cracks as for newly plastered walls, but if the surface is bad you may have to do a much more complicated filling job. Cracked or broken plaster will have to be ‘raked out’ carefully and cut back to a firm edge, after which the hole can be filled and the area replastered. If the hole is large, this may have to be done in stages, allowing drying-out time between each one. Always dampen the wall immediately round the part to be filled or plastered, otherwise the wall can draw all the dampness out of the filler which then quickly becomes loose.
When the holes and cracks are filled and the area has dried out, rub down to a smooth surface with glasspaper and dust off. If you plan to paint the wall, continue as for new surfaces, but if you plan to re-paper, treat the wall with a coat of size or thinned-down wallpaper paste.
Washable wallpaper and over-painted paper can be more difficult to remove. Score the surface with a wire brush or serrated scraper and give it a thorough soaking. There is a new proprietary wallpaper stripper specially formulated to ‘eat’ through painted or varnished surfaces, so you could use this if you prefer, following the instructions on the 93 tub. It is quicker and easier to use, but more expensive.
If the paper proves to be very stubborn you may have to score the surface and use a steam stripper. These can be hired and come complete with instructions, but take care not to scald yourself while working. When the walls are completely stripped continue as above, depending on the type of new surface you plan to use.
Vinyl wallcoverings are easy to strip — simply peel off the top, patterned layer of vinyl and it should leave a soft backing paper on the wall. Re-stick or patch any peeling areas and, if you plan to repaper or use some other wallcovering, there is no need to remove the backing — use it as a lining. If you plan to paint the wall strip off the old backing as for ordinary wallpaper. NOTE: if polyethylene light wallcovering has been used, the paste will have been applied to the wall. The wallcovering will come away easily, but you will probably have to scrape or rub off the old wallpaper paste before washing down and preparing the wall.
Previously tiled walls and ceilings
If ceramic tiles are firmly stuck to the wall, you may be able to retile or redecorate over them , since removing them can be a very messy job. Otherwise, they will have to be chipped off using a cold chisel or brick bolster and hammer. If the tiles are Victorian or Edwardian patterned ones, they are probably worth preserving, so work very carefully. You will have to re-plaster the wall unless you plan to use woodcladding, laminate, wall-boarding or other covering which is battened-on to the wall.
Cork tiles can be difficult to remove as they will have been stuck on with impact adhesive, which means lumps of tile will remain firmly stuck to the wall and will have to be chipped off as above. If possible, don’t remove them; use a new surface which can be battencd-on, or rccolour the tiles with wood stain or cross-line with lining paper and hang the new wallcovering on top. You may find that you have to size the cork several times before lining as it can be highly porous.
Polystyrene tiles are frequently found on ceilings and should not be painted, since this makes them a fire hazard. If the ceiling is in a good condition, just wash down. If the tiles are dirty or damaged, you will have to remove them — prise them off with a small cold chisel and hammer if necessary. Scrape off the old adhesive and treat as for newly plastered ceilings.
Acoustic tiles can be painted. Wash them down, then prime with a stabilizing primer before painting. If they have been painted already, treat as for previously painted surfaces.
Previously painted woodwork and metal
Wash down with sugar soap and water, household soda, or detergent and water, taking care to remove all grease or old polish from areas which are frequently handled, such as doors. Rub down with fine grade glasspapcr or ‘wet-and-dry’, dust down or wash off using clean warm water. Make good any cracks and continue as for new wood and metal. You may have to patch-prime before undercoating.
If the paint surface is poor, completely strip offthe old perished paint. Remove all loose or flaking material with a scraper, and use a shavehook for difficult-to-reach corners. Then strip off any remaining paint with a proprietary stripper or blowtorch – use this carefully, to make sure that you do not singe the surrounding surface or crack any window glass. Scrape the paint as it blisters, and clean up perished paint as you go along to avoid treading it all through the house. If you use a liquid chemical stripper, follow the instructions carefully, wear rubber gloves and protective clothing. Make sure that the room is well ventilated and work on small areas at a time, taking care not to spill the stripper on other surfaces. A new chemical stripper which looks like thick paste and comes in a tub is very good for coping with carved and other intricate areas, but is a bit expensive to use for all paint stripping.
For safety’s sake work without the ‘help’ – or hindrance – of children.
Clean the surface with white spirit to remove all trace of the stripper , sand down, dust off, and continue as for new wood and metal – use a rust-preventer under the primer and undercoat on metal radiators and pipes, particularly in areas of high condensation.
Previously varnished woodwork.
Basically you can treat a varnished surface as a painted one – wash down, sand and rinse. If the varnish is pitted or badly discoloured, or you plan to paint the wood, completely remove the old surface. Scrape, if necessary, then use a chemical stripper as for painted woodwork. Treat as new wood.
If the building is a new one, or part of it is a new extension, the wood and metal may be ready-primed. If so, treat as interior primed woodwork and metal. Otherwise prepare as follows, remembering to prime bare metal as soon as possible to avoid rust forming.
New, unpainted metal
Make sure it is free from oil and grease, and wipe over with white spirit.
Iron and steel
Remove any rust and loose scale by scraping and wire-brushing; for less severe rust, use an emery cloth. Prime at once with a universal primer.
Galvanized iron is best left to weather and lose its shine, then prime with universal primer. If you cannot wait, rub down with medium grade glasspaper, wipe over with white spirit, wipe clean and prime with chromate metal primer.
Aluminium should be rubbed down with fine grade glasspaper and white spirit. Wipe down and prime as galvanized iron.
Bitumen-coated metal should not be painted until the coating is hard and well weathered. Then it can be rubbed down and primed with aluminium sealer, following by wood primer. Then apply an undercoat suitable for the gloss finishing coats you have selected. NOTE: some garage doors, particularly the up-and-over type come already primed, and these only need treating as prc-primed indoor metal before undercoating. Others have a factory applied finish and, if possible, this type should not be painted, or they will need constant re-painting.
Many new gutters, fall pipes, soil pipes and so on are made of plastic. This does not need painting, and the universal grey colour blends with most bricks and colour schemes. Many experts say do not paint plastic – partly because the joints can be clogged with paint and subsequently difficult to remove if you want to do any repairs. But if you want to paint plastic to blend with the house or existing ironwork, remove any grease with white spirit, then undercoat and topcoat with a suitable paint.
Previously painted metal
The chances are most metal work will have some rust. If pipes and gutters are very bad, it is better to replace them. You will find the plastic do-it-yourself type much easier to handle, but you may have difficulties with sizes – new piping does not have the same circumference as some very old iron work, so you may have to replace the whole run of piping. Treat new metal work or plastic piping as previously described. Rust, loose scaling and dirt should be treated by brushing with a wire brush, scraping where necessary, or rubbing with emery cloth. Rub down with medium grade glasspaper, prime any bare parts and undercoat. Any type of guttering can be painted inside with bituminous paint to protect it.
Metal windows need special care -remove old perished paint, rust and so on and replace defective putty with metal glazing putty. Prime and undercoat as necessary. If the paint is in poor condition, burn or strip off then prime and undercoat as for new metal.
New, unpainted woodwork
Treat as for unpainted woodwork indoors, prime and undercoat. If you intend to seal or varnish exterior woodwork: decorative wood panels, doors, frames and so on, treat as for indoor woodwork, but apply extra coats of sealer or varnish, lightly rubbing down between coats. Varnished woodwork in a sunny, very exposed or coastal position needs fairly frequent rubbing down and re-varnishing, so painting might be a better treatment. The word ‘varnish’ always suggests a high gloss, but many of the new wood sealers and varnishes have a matt or semi-matt finish.
Timber claddings look best left natural but treated with a solvent preservative or sealed and varnished. Creosote is not a wise choice for wood cladding as it darkens the 95 wood and usually hides the natural grain. If creosote has been used, let it weather, then rub the surface down and varnish. You can paint it if you first apply an aluminium wood primer.
Previously painted woodwork
Treat much the same as for interior woodwork, by scraping and cleaning down if the surface is fairly good, but any old blistering and perished paint must be burnt or stripped off, the surface rubbed down, bare areas patch-primed, or the entire surface newly primed, before the undercoat is applied.
Wooden window frames are often the worse for wear, and any defective putty must be replaced, and defective wood cut out and replaced. Small holes can be filled with proprietary wood filler. Sometimes on older houses the sills of wooden windows are painted stone or concrete. Perished paint must be completely removed, the sill scraped clean and smooth and cracks or holes filled. Fill small ones with exterior quality proprietary filler: larger areas with a cement/sand mix. Leave to dry, sand smooth, prime with masonry sealer and undercoat.
Most wood and metal surfaces inside and out are best rubbed down or sanded by hand. Sanding woodwork with an electric sander can, in fact, do more harm than good, resulting in a very uneven surface if you become too ‘tool happy’. But if there is a lot of smoothing down to do on exterior window sills, or other flat surfaces, a mechanical tool can be used, with great care. Remember, if you use electric tools outside they must be fitted with a heavy-duty exterior cable. Always make sure you work with the cable in a position where you cannot possibly damage it with the tool.
Exterior walls do not always need painting – in fact, it is a pity to paint an attractive-coloured brick and sacrilege to paint a mellow stone wall. However, you can waterproof the walls without spoiling their ‘natural’ appearance.
New walls should be in a good state of repair, but may need a gentle scraping to remove spare bits of mortar. Never use a wire brush, and do not use the scraper too heavily on soft surfaces such as brick and stone. Apply two coats of masonry sealer to seal the surface and make it waterproof. Some sealers contain a fungicide, which can make the wall look darker or bright red, but this will fade. If you want to colour new walls, they can be painted without further preparation — use a water-based masonry paint.
If old walls are to be sealed or painted, inspect the pointing and, if necessary, re-point. If damage is extensive it would be wise to engage a builder to do the re-pointing.
Previously painted walls. Brush down with a stiff brush to remove loose and flaking materials. Rake out large cracks and fill with a sand/cement mix. Fill small cracks with exterior quality proprietary filler. Allow to dry, sand down edges and dust off.
If the walls are stained , repair the fault first and leave the wall to dry out. Scrape or brush off any mould or algae, then sterilize with bleach solution. If necessary, prime with alkali-resisting primer before painting with masonry paint.
If the wall is pebbledashed, and the condition is poor, remove any loose or broken pieces to expose the smoother rendering underneath and treat the exposed part with stabilizing solution. Then mix masonry paint with sand binder, extra sand and water to a thick creamy consistency and use this to fill the gaps before stippling the surface to match the texture of the surrounding wall – ‘feather’ the edges into the existing pebbledash, so that the filler is not too obvious. Leave to harden before painting. 96