· Michael Blair
The default advice is to strip wallpaper before painting, and it is usually right. In older Nashville houses with original plaster, or where paper was hung directly on unprimed drywall, stripping can do more damage than the paper was doing.
When painting over is defensible
When the paper is well adhered across the whole wall, when it is a single layer, when it has no vinyl coating, and when removal risks the substrate. Paper hung on unprimed drywall is the classic case — the facing paper of the drywall comes off with it.
It is a compromise rather than best practice, and it should be a decision rather than a shortcut.
When to strip regardless
Any seam that is lifting, any bubble, any evidence of moisture behind it, and any textured or heavily embossed paper that will telegraph through paint. Multiple layers should always come off.
Vinyl-coated paper cannot be painted successfully without removal or at minimum thorough scuffing and a bonding primer, because paint will not adhere to the vinyl film.
- Lifting seams or bubbles: strip
- More than one layer: strip
- Any sign of moisture behind it: strip and find the source
- Heavy texture or embossing: strip
- Vinyl coating: strip, or scuff plus bonding primer
How to do it so it holds
Clean the surface, then glue down every loose seam and edge. Skim any damaged areas. Then use an oil-based or shellac-based primer rather than water-based, because water reactivates wallpaper paste and lifts the paper you are trying to fix in place.
After priming, skim the seams so they do not read as lines through the finish, sand, spot-prime the skim, and only then paint.
What it costs you later
It becomes permanent in practice. Painted wallpaper is considerably harder to remove than unpainted, because the paint seals it against stripping solution.
Disclose it if you sell. It is not a defect, but a buyer discovering painted-over paper mid-renovation reasonably feels they were not told something.