Repairing plaster walls
1. Mark a rectangle on the wall which includes the hole.
2. With a knife or key hole saw cut out the rectangle being careful not to break it.
3. On a scrap piece of plaster-board, copy the section of the wall.
4. Then mark a frame about 2" wide around the section of wall.
5. After cutting, remove the paper on one side and the plaster from the frame around the patch. The 2" frame of paper will stick out like an ear all around which will hold the patch in place.
6. Spread patching plaster around the edge of the hold and around the edge of the patch. Put the patch in the hole and press the paper ears into the plaster and hold it while it sets.
7. Sand lightly and paint.
1. Cut a piece of metal plaster lath or heavy screen larger than the hole.
2. Fasten one or two wire ties to the lath and insert through the hole.
3. Pull the lath up behind hole and wire to a stick of wood placed across the hole on the front side of the wall.
4. Moisten the edge of the hole and spread a base coat of patching plaster to within 1/8" of the finished surface. Roughen the surface with a stick or nail so the finish coat will stick.
5. After the base layer is dry, remove the stick and clip the wires close to the surface.
6. Trowel on the finish layer being sure it is flush with the wall surface.
7. Let it dry well and then paint.
8. If the patched area is large, apply a coat of sizing before painting.
This article was written by Anne Field, Extension Specialist, Emeritus, with references from Michigan Extension bulletin Wall Repair and Fasteners.
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