Remove furniture from the room if possible. Cover flooring with a tarp. Remove baseboards if you wish, or tape them to protect them from the drywall compound. Remove all extruding nails, picture hangers, etc. from the paneling. By hand or with an electric sander, sand the paneling using medium-grit sandpaper to remove dirt and lightly rough the surface. Wipe the surface with a damp cloth to remove sanding dust. Decide which finish texture you wish to achieve, and practice the method on a spare piece of scrap wood or cardboard.
Smooth and level the surface. If any seams are bulging or loose, use nails to secure to the wall. Apply self-stick fiberglass tape over each paneling seam. The tape should be as flat as possible; do not push the tape into the seams.
Mix only as much drywall compound as you can use -- it dries rather quickly. If you have seams or grooves to fill, mix just enough for that, fill them, allow them to dry, then mix more compound to texture the walls. Following manufacturer's directions, place water in the bucket, and slowly add the drywall compound, blending either by hand or with the beater attachment on your electric drill. Make sure all lumps are gone.
If you are applying drywall compound by hand, the mixture should be a bit thicker than if you are using a drywall sprayer. The consistency for a sprayer should be similar to pancake batter, or slightly more watery. For manual application, it should be closer to thick paint.
Trowel about 1/8 inch of drywall compound over the tape, then smooth and remove the excess compound by drawing the trowel over the seam at a 30- to 45-degree angle. Press hard enough to remove excess, but not so hard that the tape moves. Fill any grooves with compound, then use the trowel to level with the surface. Allow the compound to dry. When dry, the surface should be smooth, relatively flat and without an obvious line. Sand any high spots as necessary. It doesn't have to be perfectly flat if your finish method is highly textured.
Apply drywall compound for the finishing layer. Only apply the compound to as much wall as you can texture before it dries -- you should have a good feel for this from your practice session. Allow the compound to dry approximately 20 to 30 minutes, depending on ambient temperature.
If using a sprayer, spray the walls per manufacturer's directions. If applying drywall manually, use either a trowel or a paint roller to apply. You will need to make peaks and valleys in the texture to attain a knocked down look. Use a paint roller, or dab a crumpled plastic or paper bag or similar item to make the peaks.
Create knockdown texture by flattening the peaks in a random pattern. Varying the direction you run the trowel over the drywall compound keeps the pattern more random. Using a 12-inch trowel, lightly place the flat edge at approximately a 15- to 30-degree angle, and draw over the peaks of the texture. Press gently -- you want the peaks to flatten but the valleys to remain intact.
Things You Will Need
- 5-gallon bucket
- Drywall compound
- Electric drill
- Beater attachment
- Drywall sprayer
- Paint roller
- Fiberglass tape
- Special tools are not necessary to apply drywall compound. Nearly every tool used for the finishing steps can be substituted with items you normally find around the house. Instead of a specialty trowel, use straight-edged cardboard or plastic to achieve a knockdown texture.
- It does take practice to master the proper pressure to make a knockdown texture. Take time to practice before you start, or begin on a wall that is hidden behind a large piece of furniture.
- Use a tarp to cover furniture and flooring. Drywall can be cleaned off, but it is tedious.