Sand the entire wall using a medium-grit sandpaper. Wipe the wall with a damp rag to remove any drywall dust.
Use a putty knife to apply a small amount of joint compound onto the edge of a drywall trowel. Holding the trowel at a 90-degree angle, apply a light, even coat of plaster onto the surface. Do not apply more than 1/4 inch of plaster at a time. Fill in all holes and dings on the wall's surface using the trowel and joint compound. Compare the technique to icing a cake or buttering toast. Allow the first coat of plaster to dry about four hours.
Lightly sand the dry plaster with a fine- to medium-grit sandpaper to remove any loose plaster. Wipe off any dust with a damp rag. Add more wet plaster to the wall with the trowel, allow it to dry and continue the process until all grooves have been filled in and evened out. Several layers of joint compound may be necessary.
Things You Will Need
- Medium-grit sandpaper
- Putty knife
- Joint compound
- Drywall trowel
- Slight cracking or hazing of the plaster may occur. Simply continue to fill in and smooth the plaster onto the surface. The cracks will be filled out when additional layers are added.
- Always clean the drywall trowel after applying a skim coat. Use an empty 5-gallon bucket filled with warm water. Scrub the trowel with a rag to remove the plaster.
- If the wall is severely damaged where the drywall paper has been ripped up and removed, coat the walls first with a water-based primer and sealer such as KILZ. Consider texturizing the wall if the drywall has severe grooves and indentations. The wall will not be smooth, but the texture will disguise damage caused by removing wallpaper.
- Paint the walls after the last layer of skim has dried, with a water-based primer and sealer. Allow it to dry and continue with a coat of latex paint.