Complete your interior fit-out project with a smooth drywall finish. Finishing drywall is done over three stages, each requiring a new application of compound. Each coat gradually expands in width, eliminating the imperfections of the last to ensure seams are properly reinforced. The last coat should be sanded or smoothed out to remove irregularities.
There are 12 steps to completing this project:
Cover screw or nail heads with joint compound, troweling it on with a 6-inch drywall knife. Add enough compound to fill the dimple left by the screw, and level the compound with the knife. If a screw missed the stud, it will eventually work its way out; so take it out now and fill the hole.
Starting at the top of the wall, rest one end of the blade on the raised part of the corner bead and the other end on one of the walls. Draw the knife along the wall toward the floor, applying compound to the corner. Repeat on the second wall.
Working with the 6-inch knife, fill the trough created by the bevels with joint compound. Pull the knife along the trough to create a smooth, continuous bed of compound.
Once the compound is in place, cover the seam with a single piece of tape. (Multiple pieces are likely to slip and wrinkle when you embed the tape.) Push the tape into the compound every foot or so to hold it in place while you work.
Starting in the centre of the wall, hold the 6-inch knife so that it bridges the tape and is at a slight angle to the seam. Draw it along the wall, applying enough pressure to embed the tape and also remove excess joint compound. Leave just enough compound under the tape edges to hold them in place — about 1/32 inch. When you reach the corner, go back to the middle of the wall and work toward the other corner.
Apply a thin layer of joint compound to both sides of the inside corner with the 6-inch knife.
Fold a strip of drywall paper tape in half by pinching the strip and pulling it between your thumb and forefinger. Position the end of the folded tape strip at the top of the corner joint. Press the tape into the wet compound about 12 inches.
Start at the top of the room and draw the knife along one of the walls, smoothing the tape. Repeat on the other wall. Move the knife a couple of inches away from the corner and pull from ceiling to floor, removing the excess compound left by the first pass.
Let the first coat dry thoroughly. Apply a second coat of compound over the screws. Coat the outside corners and seams as before, using an 8-inch knife. Feather the edges so that they are about 2 inches wider than those of the first coat. Feather the edges of any butt seams so that they are about 4 inches beyond those of the first coat.
At this point, finish the inside corners one wall at a time. Apply a coat of compound on one wall, feathering it out 2 inches beyond the first coat. Let the compound dry, then repeat on the second wall.
Once the final coat has dried, smooth out any irregularities with a damp sponge. This works just as well as sanding — without creating dust.
Ceilings and some high areas may be easier to reach with a pole sander. Put 200-grit sanding mesh on the pad and run it back and forth along the seams. Sanding mesh is a piece of screen coated with abrasives; it won't clog when you sand with it.
