For preparing surface wallpaper stripper or warm water and washing-up liquid wallpaper paste (for soaking heavyweight paper) wire brush or serrated scraper steam stripper (if needed) wallpaper stripping knife medium wet and dry glasspaper cellulose filler (if needed) matchsticks (if needed) glue size or wallpaper paste (for sizing walls) fungicidal adhesive (for sizing if using vinyl paper) old brush or paint pad.
To remove the existing paper you will have to soak it with a solution of warm water and washing-up liquid or proprietary wallpaper stripper. Allow extra soaking for heavyweight papers – add a handful of wallpaper paste to the water so the water stays on the wall long enough to soak through to the adhesive.
Stripping off
Score the surface of washable wallpapers with a wire brush or serrated scraper to allow the water to soak through to the backing. If the paper is several layers thick or you cannot score it easily, it may be worth hiring a steam stripper to do the job quickly, but use it carefully since it can damage the plaster underneath. Remove the paper with a wallpaper stripping knife; don’t be too vigorous and try not to dig the knife into the plaster, as you will have to fill any holes you make. Remember you can strip certain types of wall covering just by loosening a corner and pulling off each length, leaving the backing paper on the wall. If this is firmly fixed, use it as a base for re-papering or soak and strip as already described. Rub down the bare walls with wet and dry glasspaper to remove any final nibs of paper. Fill any cracks or holes with cellulose filler and, when hard, rub down any ridges with medium wet and dry glasspaper to form a flush finish. If you have removed any fixtures, push matchsticks into the screw holes, allowing them to protrude about 6mm. When you hang the new wall covering ease it over the matchsticks so they poke through the paper and indicate the position for refitting the fixtures later.
Sizing the walls
Before papering you will have to size sound, porous walls; this is to improve adhesion and ensure the water from the paste is not absorbed too quickly for you to position the paper correctly. You can buy a proprietary glue size or make your own by diluting wallpaper paste according to the manufacturer’s instructions. When using vinyls, size with a diluted fungicidal adhesive since mould may develop on the wall if you use a diluted cellulose adhesive. Apply the size liberally to all parts of the wall with an old brush or paint pad; take care to wipe off any that gets onto painted woodwork immediately as it will be difficult to remove later. Leave the size to dry thoroughly.