Patching Holes in Plaster and Drywall

House Doctor | Gary Dymski

January 17, 2002

For the longest time, I dreaded patching holes in drywall. And with five children bouncing around the house, including three hockey players, my walls needed plenty of patching. But my patches ended up looking like sinkholes or lumps. Often I'd put too little compound in the hole, then have to add layers. If I used too much compound, things would get sloppy and the hole would be replaced by a lump. Out came the sanding block.

It was an awful lot of work to patch a hole three or four inches in diameter.

Then I developed my own technique, with a huge assist from nylon mesh drywall tape. This 2-inch tape has a sticky side that adheres to the wall, and when drywall compound is applied, the tape hardens like a plaster cast.

So, here's a foolproof way to patch holes. You'll need a sharp utility knife, a 10-inch drywall knife, nylon tape, some drywall compound and just a little patience.

First, frame the hole by cutting a square area around it. Don't cut too deeply. You want to peel the top paper layer and paint away so the interior brown paper covering remains on the gypsum board. Remove any chips or broken pieces from the hole. If the wall is covered with an enamel or semigloss paint, you might want to use some sandpaper around the remaining painted area. Roughing up the paint helps the drywall compound adhere.

Next, tape over the hole. Cut the nylon tape into strips just a hair shorter than the square frame around the hole. The idea is to tape the opening so the thickness of the tape replaces the paper that was peeled away. Be sure to apply the tape sticky side down.

It's OK to let the strips of tape overlap by a half-inch or so.

Now apply thin coats of drywall compound. I usually keep an inexpensive plastic drywall knife in the toolbox for these repairs. Don't make too many passes over the opening because the mesh tape has a tendency to unravel at the edges. Work an area about 3 to 5 inches around the hole. Get the compound as smooth as possible, then wait 24 hours.

When the compound has dried, the tape will have hardened. You might be able to see through the mesh tape, but it's strong enough so you can add another couple of layers. Wait at least 12 hours before sanding or adding each layer. It usually takes two to three layers to patch most holes.

I use 220 or 400 grit paper before applying a primer. Often, the patch needs just one sanding. In between layers, try wiping away dry, excess compound with a sponge or wet rag. It makes for a lot less dust.

For large holes, you might have to add some backing. For this, cut a scrap piece of drywall that is just a little smaller than the hole in the wall. Dab some adhesive (Liquid Nails works fine) on the scrap piece so it will stick to the inside of the wall. To keep the scrap piece in place, try fastening a drywall screw to the scrap so the screw extends to the middle of the hole. This way, you can grasp the screw to pull the scrap piece toward you. Once the adhesive dries and the scrap piece is secure, remove the screw and proceed with the taping of the opening.

Plaster walls can be repaired with the mesh tape, too. To prep the wall, you might have to use a chisel or putty knife to frame the hole. Wipe away the plaster dust before taping. If the tape still won't stick, try applying a thin layer of compound to the area and then press on the tape.