How to Wallpaper Over Painted Walls
Matt, silk or gloss: what each finish needs before paper goes on it, the thirty-day rule, dark colours, and the finger test for paint that will not hold anything
Yes, and most people do. Wash the wall, sand back any sheen so the paste has something to grip, fill and sand any damage, and dust it off. If the paint is new, give it thirty days to cure first. If the wall is dark and your design is pale, paint it out to a neutral base before you start.
Matt emulsion, the easiest case
A matt emulsion in good order is a good surface to paper over. Wash it with sugar soap, rinse, let it dry, and dust it off. No sanding needed unless there is damage to make good.
Silk, soft sheen and eggshell: key it first
These have a sealed, slightly glossy surface, and paste does not grip it. Sand the whole wall lightly with medium abrasive paper. You are taking the shine off, not removing the paint. Then wash off the dust and let it dry.
Skip this and the paper will hold for a few days and then let go in sheets. It is one of the most common causes of a whole length peeling away with the paste still on its back.
Gloss: key it thoroughly
Rare on a wall, common on panelling and woodwork. Sand it properly to a dull finish, or prime it, before anything goes on it.
Chalky, powdery or very old paint
Rub a finger across the wall. If colour or powder comes off, the surface is unstable and nothing will bond to it reliably. Old distemper and some very flat paints do this. Wash it back as far as it will come, then seal with a mist coat of matt emulsion and let it dry.
New paint needs thirty days
Emulsion is dry to the touch in hours and still curing for weeks. Paper hung onto uncured paint can lift the paint film off the wall as the paper shrinks. You get a length that peels away carrying a sheet of your new colour with it.
Thirty days, whether you have painted the whole wall, painted out a dark colour, or just touched in a filled patch.
Dark and strongly coloured walls
A dark wall under a pale paper does not show as an obvious block. It shows as a shadow that makes the whole wall look slightly grubby in daylight, and it is impossible to unsee.
Paint the wall out to a neutral base first, two coats of a light matt emulsion, and then wait the thirty days. It adds a month to the job and it is the difference between the colour you chose and a muted version of it.
The reverse is worth knowing for dark colourways: painting a narrow stripe of a close-matching emulsion down the wall where each seam will fall means a seam that moves slightly as it dries shows a dark line rather than a white one.
Step by step
- Take everything off the wall and cover the floor.
- Scrape back any flaking paint and feather the edges with abrasive paper.
- Fill holes and cracks, let the filler dry, sand flush.
- Key the whole wall if the finish has any sheen.
- Wash down with sugar soap, working bottom to top, then rinse.
- Let the wall dry completely.
- Seal any patchy, chalky or heavily filled areas with a mist coat.
- Dust the wall off with a clean dry cloth immediately before hanging.
Painted-over wallpaper
If the wall is painted wallpaper rather than painted plaster, treat it as wallpaper: it should come off. Paint seals the old paper against water, so stripping is slower and needs scoring.
Peel and stick on painted walls
Removable paper is stricter. It needs a smooth, firmly bonded, fully cured painted wall, and it will not hold on chalky or powdery paint at all, because the adhesive grips the loose surface layer rather than the wall. Do the finger test before you order.
Can you wallpaper over painted walls?
Yes. Wash, key any sheen, fill and sand damage, dust off, and allow new paint thirty days to cure.
Do I need to sand a painted wall before wallpapering?
Only if it has a sheen: silk, soft sheen, eggshell or gloss. Matt emulsion in good condition needs washing, not sanding.
Can I wallpaper over silk emulsion?
Yes, once it has been sanded to take the shine off. Unsanded silk is a common cause of paper peeling away in whole lengths.
How long after painting can I wallpaper?
Thirty days.
Will a dark wall show through my wallpaper?
Under a pale design, yes. Paint it out to a neutral base first.
What if the paint rubs off on my hand?
The surface is unstable. Wash it back, seal with a mist coat of matt emulsion, and let it dry before papering.
