Symptoms
- Wall looks bumpy or wavy under raking light
- Old patches, texture, or repairs visible as slight ridges
- New paint expected to look glossy or smooth
Likely causes
- CommonMultiple old patches with different texturesYears of small repairs can leave a wall with an inconsistent surface.
- CommonOld texture not fully removed or skimmed overLeftover texture under new paint will still show as unevenness.
- PossibleWall never properly sanded after previous finishing workRough joint compound spots left unsanded show through paint, especially glossier sheens.
What to do
- Run a hand over the wall in different areas to feel for rough or raised spots.
- Sand rough or raised areas smooth with medium then fine sandpaper.
- Apply a thin skim coat of joint compound over larger uneven sections.
- Let dry fully, then sand smooth again.
- Wipe the wall down with a damp cloth to remove all dust before priming.
- Prime the wall, especially patched areas, so they don't absorb paint differently.
- Choose a flatter paint sheen if the wall has minor imperfections you want to minimize.
Tools and parts
- Sanding pole or block
- Taping knife
- Damp cloth
Joint compoundSearch: “lightweight joint compound for skim coating”
When to call a pro
Call a drywall finisher for a full skim coat if the whole wall or room needs leveling before painting.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.