Easy Drywall Patch for Beginners: Plywood Backing and Mesh Tape

Can someone who has never cut drywall patch a hole in a wall? The Vancouver Carpenter says yes, with a method he calls the easiest and simplest, though not the fastest or most professional. It suits holes from fist size to foot size.

Cutting and backing

The new piece is scored lightly on the paper with a knife, pushing a little harder on each pass, then snapped. Scoring a slightly bigger outline than the piece avoids cutting the hole too small. Loose paper is cleared until solid drywall surrounds the hole.

Plywood backing goes behind the hole, overlapping it by about an inch to an inch and a half. He prefers plywood because it doesn't split when screwed. 3/4 in. ply is used, though 1/2 in. is best because it takes the least space in the wall. He uses 1 1/4 in. coarse-thread drywall screws. Each should sink just far enough that you can't hear it, without tearing the paper, since a torn paper screw doesn't hold and could blister. A patch of about 6 by 6 or 5 by 5 needs only four screws.

Tape and first coat

He checks that all the drywall is solid with no loose chunks or blisters. For a small patch, fiberglass mesh tape works, though he calls paper tape the best. Overlap is kept minimal for beginners to limit build-out. The first coat of all-purpose mud is a thin skim that just embeds the tape, with edges feathered by pressing down on the blade, and it dries overnight.

Second coat and sanding

The second coat uses a 10 inch knife; the first used a 5 inch, and he says 5, 6 or 8 inch all work for that stage. Mud can be thinned with a little water in a pan. He starts about 6 inches above the patch and aims for roughly a 1/16 in. layer over the tape, feathering both sides. The tape should be totally buried. After drying overnight he sands with a sanding sponge rather than a pole sander, holding the pan against the wall to catch dust, and wearing a mask.

Painted walls and touch-ups

On a previously painted wall, everything except the new drywall tends to bubble, so he skims twice: he loads mud on, pulls it off hard to fill pinholes, then does another skim leaving some material as a sanding coat. He avoids touching up after sanding because the sanded patch ends up at a different consistency and leaves a ridge. He does touch-ups before sanding instead, without compressing the mud, and uses a fan to dry it.

Final sanding and primer

With a light shining directly down the wall, he sands slowly with an angled sponge, in flat, often circular motions, blending the edges. Leaving the edge heavy is, he says, one of the biggest beginner mistakes. A coat of primer sealer dried in about five minutes with a fan. His only visible defect was an edge he could have sanded a little more.