Patching Damaged Drywall – Bob Vila
The virtues of drywall
Drywall has been the preferred material for wall finishing for almost a century because it is so easy to install and finish. Another of its virtues is that it is easy to repair when damaged. If there are scratches or small dents, a quick brushing of the grout with a 3 or 4 inch putty knife and a little sanding before priming and painting is sufficient. For small holes up to 3 inches, self-adhesive plastic mesh tape, followed by a layer or two of repair agent, will work. For medium-sized holes between 4 and 6 inches, try a drywall bandage.
First, make sure there are no electrical wires around, then use a jigsaw to cut the hole into a neat square or rectangle. Transfer this shape to a new piece of drywall, add 2-inch margins, and cut out the larger patch piece. Cut off the back and plaster of paris in the 2-inch margin, but leave the face paper uncut. Spread the patch around the outside edges of the hole and press the bandage in, feathering the edges. Let it dry. Then sand and paint over with filler. Finally sand, prime and paint again.
Repairing large holes
For really large holes, you can use the tie and twist bracing method. Cut a piece of drywall or a length of 2 × 4 a few inches larger than the hole. Drill two small holes in the center and loop a 2 foot piece of string through like a button. Tie the ends around the center of a stick. Apply glue to the back edges of the hole in the wall. Glue the patch on and twist the wand off your side of the wall until it sticks. Then fill in the remaining space with drywall patch pieces and mesh tape. Finish with the mass as usual, cutting the string and pulling it out just before it dries.
Patching of super large holes
For super-large holes larger than 12 inches wide, cut the drywall back to the next two studs and expose half of them. Cut a new sheet of drywall to fit and secure it as usual with drywall screws, grout, and tape.