Over time, a drywall ceiling may require repair from cracks, water damage, or holes. Different problems require different solutions. Follow these tips for patching up different types of damage to a drywall ceiling.
Tip #1 - Patching Ceiling Cracks
Numerous ceiling cracks can be caused by studs or joists that have shifted over time. For widespread damage, remove all the damaged drywall and add support pieces that run perpendicular to the wooden joists that are already there. For single cracks, gently knock away any loose drywall with your fingers.
Thin out the drywall compound by adding water and filling in the crack with a drywall knife. Add a piece of fiberglass mesh drywall tape the length of the crack. Allow drying 24 hours. Add 2 more coats of drywall compound. Allow it to dry completely between coats. Sand lightly before priming and painting.
Tip #2 - Fixing Ceiling Sags from Water Damage
In bathrooms or other moisture-rich areas, water damage may cause your ceiling to sag. You can reattach the sagging drywall to its seam with screws, especially if the water damage is relatively new. If you can reach the other side of the ceiling through your attic, check to see if any insulation or other material has fallen onto the sagging drywall before screwing it back in place.
Remove any material from the top. Screw back to the support. Space screws about 8-inches apart. Fill in screw holes with mud and sand smooth before applying prime and paint. Remember to replace any insulation removed.
Tip #3 - Fixing Popped Nail or Screw Heads
Nails or screw heads may pop out because of shrinking studs. Cut out any bunched drywall around the screw or nailhead. Screw or tap the head until it no longer protrudes from the ceiling. It will be slightly indented. Fill in the indentation with mud and smooth it with sandpaper or a damp sponge.
Tip #4 - Fixing Small Holes in Drywall
Small holes (less than 3-inches) can be fixed quickly by adding a self-adhesive drywall patch that can be purchased at most hardware stores. After pressing on the patch, cover with mud compound and allow to dry for 24 hours.
Use a knife that is several inches larger than the hole you are patching. Add another coat with a knife a few inches larger than the first, feathering out several inches past the patch and smoothing off excess mud with a knife. Smooth by sanding or wiping with a damp sponge.
Tip #5 - Fixing Large Holes in Drywall
Holes that are larger than 3-inches should be replaced with a patch cut from a sheet of drywall. Measure the area of damage and cut out a square or rectangular hole from the old drywall. Use the same measurements to cut out a piece from the new drywall to replace it. If there are no studs behind your drywall to which you can attach the patch, screw wooden boards to either end of the square hole that is a few inches longer than the length of the hole.
Screw the drywall patch into these added supports. Cover the joints with fiberglass mesh tape and spread a layer of mud over the tape and screw holes. Allow drying before adding two more coats in the same fashion as described for the small holes. Sand or smooth with a damp sponge before priming and painting.