Drywall, although efficient for most average homes, can be broken. One fairly common place for breaks is behind a door. When a door is opened with too much gusto, a hole can be punched right into. Now what? Well, it’s not that hard to repair.
Here are two patching methods that have proven effective time after time.
California patch (for patches up to about 6 inches square):
Cut a rectangular piece of drywall approximately 4 inches larger in each dimension than the hole. On the back side of the board lay out lines 2 inches in and parallel to each edge. With a utility knife cut through the back paper and snap the gypsum core on the line of the cut. Do not cut through or tear the face paper. Carefully peel the perimeter pieces of gypsum away from the face paper to leave a rectangle the size of the patch with a 2-inch wide flap of face paper extending from all edges.
This flap will take the place of tape on the joint. Lay the patch on the wall and scribe around the wallboard body of the patch. Trim the hole in the wall to match the shape of the patch. (This is easier than cutting the patch to match the wall.) If the patch is snug in the hole the repair will be quite strong. Install the patch by buttering the edges of the patch and perimeter of the hole with mud. Place the patch and skim the top of the paper flap with a thin application of mud, just as you would a taped joint.
Cut the patch, scribe its outline on the wall and trim the hole to fit. You can either cut a straight patch and use tape at the joint or use the California patch method and do without tape. Cut one or more scraps of wood at least 2 inches wide and long enough to span the hole with an additional 2 inches to 4 inches in each direction beyond the edge. Choose material that will grip a drywall screw well.
Slip the wood into the hole spanning the gap from behind. Leave enough space so you can get a firm hand grip on the wood. Drive a drywall screw in each end drawing the wood tight up to the back side of the wallboard. Install the patch and drive two or more drywall screws through it into each piece of backing.