Painters and decorators
How to remove wallpaper paste before painting
Wallpaper paste left on a stripped wall can spoil the paint you put over it. Zinsser and Rust-Oleum both warn that it can leave new paint cracked and peeling. Get the paste off and make sure the wall is ready before you open the tin.
Sources: [1] Zinsser (accessed 2026-10-19); [3] Rust-Oleum (accessed 2026-10-19).
- Wash the residue off and rinse, then let the wall dry out completely, as B&Q advises.
- Paint only once the wall is sound, clean and dry, the condition Dulux Trade's Vinyl Matt data sheet sets.
- Then fill, seal or wait, depending on what you find.
- If some residue will not wash off, Zinsser makes a sealer for it but still says to remove it first for best results.
- Do not paint a damp wall. Dulux Trade's advice is that no paint should go on a damp surface.
Sources: [5] B&Q (accessed 2026-10-19); [9] Dulux Trade (accessed 2026-10-19); [1] Zinsser (accessed 2026-10-19); [11] Dulux Trade (accessed 2026-10-19).
This guide starts once the paper is off. If you are still deciding whether to strip it at all, the guide to painting over wallpaper covers that choice. Painting over wallpaper
Why paste left on the wall matters under paint
Zinsser's Gardz data sheet gives the reason: a water-based coating or texture finish will bring old wallpaper adhesive back to life, and that is what cracks and peels the paint. Rust-Oleum's UK guide calls removing leftover paste before painting essential, because it can leave new paint cracked, peeling or drying unevenly. Separately, it says paint over glue that was not properly taken off can reactivate it and craze, with cracks or lines showing once the paint has dried.
Sources: [1] Zinsser (accessed 2026-10-19); [3] Rust-Oleum (accessed 2026-10-19).
A German paint maker, Kreidezeit, takes the same line. It says paint over glue residue often flakes, that the residue has to be removed thoroughly before you paint, and that this holds for every water-based paint sold commercially. It adds that old glue can give off yellow dyes that work their way into the paint.
Sources: [4] Kreidezeit (accessed 2026-10-19).
1. Check whether paste is still on the wall
Expect some to be there. B&Q says that once the big strips are off you will probably be left with small bits of paper and residue, and that clearing them leaves the wall smooth and ready to decorate.
Sources: [5] B&Q (accessed 2026-10-19).
For residue you cannot see, Kreidezeit gives its own test. Wet the surface with a little water, wait 1–2 minutes, then touch it. If it feels sticky or greasy, there is still glue on the wall.
Sources: [4] Kreidezeit (accessed 2026-10-19).
2. Wash the residue off and rinse
B&Q starts dry: brush the wall over with a stiff broom, then use a stripping knife to lift off the last scraps of paper. For paste that will not shift, it says you may need a chemical wallpaper solution.
Sources: [5] B&Q (accessed 2026-10-19).
Toolstation and Homebuilding & Renovating both suggest sugar soap for the residue, but check it suits your wall first. Screwfix says sugar soap is best suited to hard, sealed surfaces such as painted walls and is not suitable for every wall, so read the pack and test a small area before you do the whole wall. Toolstation advises a sponge and sugar soap to clear adhesive residue and says this step matters for a smooth finish if you are repainting. Homebuilding & Renovating says to scrub the residue off with sugar soap, then rinse and leave the wall to dry. Screwfix sets out how to use it:
Sources: [7] Screwfix (accessed 2026-10-19); [6] Toolstation (accessed 2026-10-19); [8] Homebuilding & Renovating (accessed 2026-10-19).
- Mix it as the pack says. Screwfix says to dilute it as directed, dissolving powder in warm water to the packaging instructions.
- Do not leave it to soak. Screwfix says it should stay on for only a few minutes before you rinse.
- Rinse with clean water and a fresh cloth, then repeat the rinse so none is left behind.
- Screwfix warns that sugar soap left on the wall can dry to streaks and stop the paint sticking.
Sources: [7] Screwfix (accessed 2026-10-19).
To finish, B&Q says to rinse the wall with water and a sponge, wipe it down with a clean rag or cloth, and then let it dry out completely.
Sources: [5] B&Q (accessed 2026-10-19).
If the wall was painted before it was papered and that paint is still sound, Crown Trade's data sheet for Clean Extreme Anti-Bacterial Scrubbable Matt says to wash it with hot water and a liquid detergent solution, changing the water often.
Sources: [10] Crown Trade (accessed 2026-10-19).
Then check your work. Kreidezeit says paste has to come out of the pores of the surface as well, and that you should do its wetting test again after washing. Once the surface no longer turns greasy, it treats the residue as removed. If some will not come off, see the residue row in step 4.
Sources: [4] Kreidezeit (accessed 2026-10-19).
3. Let the wall dry and check it is sound
Screwfix says the wall should be fully dry before you start painting.
Sources: [7] Screwfix (accessed 2026-10-19).
Product data sheets set much the same condition for the surface. Dulux Trade's Vinyl Matt data sheet asks for a sound, clean, dry surface, with new surfaces in particular fully dry. Where needed, it says to wash the surface to clear dirt, grease and dusty or powdery residue, rinse with clean water and let it dry. Crown Trade's Clean Extreme data sheet wants every surface suitably dry, sound and clean, with nothing on it that would interfere with adhesion. Zinsser's Gardz data sheet asks for a clean, dry, sound surface free of contamination.
Sources: [9] Dulux Trade (accessed 2026-10-19); [10] Crown Trade (accessed 2026-10-19); [1] Zinsser (accessed 2026-10-19).
Once the wall is dry, look it over for the conditions in the table below and work from what you find.
4. Decide: repair, seal or wait
| What you find | What the source says to do | Source |
|---|---|---|
| Dents, holes, cracks or other surface defects | Fill them. Dulux Trade's data sheet names the appropriate Polycell Trade Polyfilla. Crown Trade's names Sandtex Ready Mixed Filler for fixing holes, cracks and shallow defects, and says to patch prime bare and filled areas as for new surfaces. | Dulux Trade Vinyl Matt and Crown Trade Clean Extreme data sheets |
| A surface that is still powdery | Crown Trade's patch-prime instruction covers powdery areas too. Dulux Trade says a surface that stays powdery after thorough preparation should be sealed with a suitable plaster sealer. | Crown Trade Clean Extreme and Dulux Trade Vinyl Matt data sheets |
| Torn or loose plasterboard facing paper | Cut the loose or torn paper away with a razor, or sand it back with 80-grit paper, until you reach a sound area. Where the board is gouged, take out loose bits of the gypsum core. Zinsser says Gardz soaks into and seals damaged facing paper, turning it back into a sound surface for repairs that can be painted. | Zinsser Gardz data sheet |
| Residue that will not wash off | Zinsser lists wallcovering adhesive residue among the surfaces it recommends Gardz for, and says the product is made to seal leftover adhesive in so it cannot spoil water-based topcoats. Its data sheet still says that, for best results, residual adhesive should come off before Gardz goes on. | Zinsser Gardz data sheet and product page |
| A wall that stays damp | Hold off painting. Dulux Trade's advice on painting damp surfaces says no paint coating should go on a surface that is structurally or superficially damp, and that walls not left to dry out thoroughly can fail early through blistering and flaking. Homebuilding & Renovating says damp always has an underlying cause, and that cause has to be dealt with before you paint. | Dulux Trade; Homebuilding & Renovating |
Sources: [9] Dulux Trade (accessed 2026-10-19); [10] Crown Trade (accessed 2026-10-19); [1] Zinsser (accessed 2026-10-19); [2] Zinsser (accessed 2026-10-19); [11] Dulux Trade (accessed 2026-10-19); [12] Homebuilding & Renovating (accessed 2026-10-19).
If you use Gardz, work to its own data sheet. Zinsser says porous surfaces sealed with it are ready for finish coating after 3 hours. Separately, it gives a dry time to recoat of 3 hours at 21 °C. When dry, it can be top coated with any standard primer or topcoat paint, water-based or solvent-based. A properly sealed surface should show an even sheen when you look along it at an angle, and any area missed or coated too thinly should be coated again. Textured or skim-coated surfaces soak up a lot and may need a second coat.
Sources: [1] Zinsser (accessed 2026-10-19).
For a first coat on bare plaster, see the guide to mist coating new plaster. Mist coating new plaster
If the wall is going to be lined rather than painted, the lining paper guide picks up from here. How to hang lining paper