How to Repair a Cracked Drywall Ceiling
This Old House general contractor Tom Silva shows how to permanently patch a damaged ceiling
In this video, This Old House general contractor Tom Silva shows how to repair drywall cracks in a ceiling.
1. Climb into the attic and remove the insulation from between the ceiling joists directly above the damaged drywall.
2. Drill a 3/16-inch-diameter hole down into the 1x3 strapping and through the drywall ceiling. Be sure to center the hole between two joists.
3. Now go down into the room below and locate the hole in the ceiling.
4. Make a screwing template by first cutting and screwing together two pieces of ⅝-inch plywood; make them slightly larger than the damaged area on the ceiling.
5. Bore a series of 1-inch-diameter holes through the template, spacing the holes about 3 inches apart. Space the rows of holes 16 inches on center.
6. Hold the screwing template against the ceiling, directly over the damage area. Use the 3/16-inch-diamter hole to align the rows of holes with the 1x3 strapping above.
7. Set a small square of plywood on the floor, then wedge a 2x4 brace into place between the plywood square and screwing template.
8. Use a drill/driver fitted with a drywall tip to drive 1¼-inch drywall screws through the holes in the template, through the drywall ceiling, and into the strapping above.
9. Cut ⅝-inch-plywood backer boards to fit between the ceiling joists and the 1x3 strapping.
10. Climb back into the attic and apply construction adhesive to the top surface of the drywall ceiling.
11. Press the plywood backer boards down into the adhesive.
12. Slide shims beneath the ceiling joists to force down the backer boards.
13. Go back down into the room and run drywall screws up through the remaining holes in the template and into the plywood backer boards.
14. If the ceiling crack extends beyond the template, drive in a few screws on each side of the crack.
15. Tap out the temporary 2x4 brace and remove the screwing template.
16. Use a hammer to lightly tap along the ceiling crack to break free any loose debris.
17. Apply a strip of painter's tape to the very top of the wall to protect it from joint compound.
18. Cover the ceiling crack with adhesive-backed fiberglass mesh tape.
19. Use a flat trowel to spread a thin layer of joint compound over the entire repaired area, including the mesh tape and all the screw heads.
20. To create a skip-textured finish apply more joint compound with very light pressure, allowing the trowel to skip over the surface.
21. Let the compound dry overnight, then apply a coat of primer, followed by two paint topcoats.