To repair a basement wall crack, cut along the edges of the crack and fill the widened space with drywall compound. If the crack is deep, cut out the old section of paper tape, fill the hole with compound, apply new tape over the crack and coat the tape with compound.
To fix a crack in basement drywall, run through the following steps.
- Widen the crack
- Fill in the crack
- Add new drywall tape
- Cover the tape with compound
Cut along the edges of the crack with a utility knife. If the crack extends into the drywall paper tape, remove the area around the tape.
Fill in shallow cracks with drywall compound, let the mixture dry and then sand and repaint the wall. For deeper cracks that run into the paper tape, fill in the area with drywall compound and move on to the next step.
Cover the wet compound in the crack with a piece of fiberglass tape. Smooth the tape into the wall with a putty knife.
Cover the new strip of tape with drywall compound. Add a thin layer and let the mixture dry. Add a third thin layer to the wall if the tape is still visible. Sand down the wall between coats to smooth out bumps.