How to Fix a Crack in a Plaster Wall
- 1). Apply a layer of joint compound made for plaster walls. Be sure to push the joint compound into the crack. Use a spackle knife. The layer should be thin on the wall itself. Joint compound come in premixed and unmixed varieties. Joint compound can be purchased online and at some hardware stores.
- 2). Apply fiberglass tape over the wet joint compound. Use a spackle knife or trowel to press the fiberglass tape into the wet joint compound. Do not use paper tape. Paper tape isn't as strong as fiberglass tape. Paper tape tends to lift and bubble on plaster walls. Fiberglass tape is available at hardware stores and home improvement stores.
- 3). Put another layer of joint compound over the fiberglass tape and some joint compound around the tape.
- 4). Allow the joint compound to dry completely. When it is thoroughly dry, sand the joint compound so that it is flush with the rest of the wall. Vacuum the wall to remove excess dust before painting.
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