Patching a Plaster Wall

Fix a hole in the wall with a few common tools and some drywall supplies. Practice your technique!

When the only thing wrong with an old plaster wall is isolated damage, you can patch-plaster it- which requires familiarity with three-coat plastering techniques-or you can make a drywall patch as described here. The hardest part will be taping the joint between the drywall (e.g., Sheetrock) and the original plaster so that the patch is undetectable. Do it right and you can avoid most of the dusty sanding between coats and at the end.

MAKING THE PATCH

Remove any crumbling plaster around the area to be patched. Cut the hole opening to a regular shape, preferably back to the nearest stud. A regular shape makes the drywall patch easier to cut; exposing studs lets you nail the patch directly to the studs.

Secure edges of the old plaster with wood screws. If the plaster is sound but the plaster keys holding it to lath have broken, use screws along with plaster washers to stabilize the plaster. Cut a drywall patch to fit neatly in the opening. The gap between patch and plaster should be minimal so that the tape will span the joint. Shim the drywall patch as needed to bring it flush with the surface of the plaster. Nail or screw the drywall in place, with fastener heads set slightly below the surface (dimpled), but without breaking the paper face.

If the hole to be patched is small and misses nearby studs, the drywall may be screwed into the wood lath. (Nails won't hold.)

TAPING TECHNIQUE

You'll need a 6" flexible taping knife, a 12" flexible taping knife or a float, a hawk, and a sanding sponge, as well as remnant drywall, joint compound, and either paper or fiberglass-mesh tape (used to bridge drywall joints).