How to Repair Cracks Where Two Walls Meet

Wear a dust mask and scrape the crack in the wall where the two walls meet using a paint scraper to remove loose paint and compound.

Insert the tip of a utility knife through the tape in the corner of the wall, 3 inches above where the crack starts. Extend the cut around the crack by 3 inches to score or outline it.

Cut the loose drywall tape within the scored or outlined corner of the wall using the knife. Scrape the surface to completely remove the tape and old compound.

Spread a 1/8-inch layer of drywall compound over the corner of the drywall using a drywall knife. Extend the compound around the crack by 3 inches.

Fold a length of paper tape lengthwise in half and position it over the seam between the two walls, directly above the wet compound. Lower the tape over the compound and press it outward on each side from the center. Apply steady pressure when pressing the tape with the knife so you squeeze out the compound on both sides. Let the tape dry for the time specified on the label, since each brand has a different drying time.

Apply another coat of joint compound using a trowel, but extend it over the edges of the previous coat by 4 inches. Apply it on one wall first and let it dry thoroughly before applying it on the other wall.

Apply a third and final coat of compound over the joint, but taper its edges by 6 inches. Extending the edges further along the crack with each coat helps the transitional edges disappear. Let one side wall dry before applying the compound over the other.

Sand the surface of the compound with 100-grit sandpaper when it dries. Prime the repaired section of the wall before applying the exact shade of paint as the surrounding wall surface.