How to Patch Holes like a Pro

The easiest technique I have ever seen uses a self-adhesive tape made of super-strong plastic. To use it, you peel off the tape’s protective backing, then press the tape in place over the hole.Next, set your clothes iron to 275 degrees (permanent press) and iron the patch down tight. The heat will shrink the plastic tight, and also bond it to the wall.That’s it. You can now paint or paper right over the repair. The plastic is so thin, the patch is virtually invisible. You can make it even better by sanding the edges of the tape lightly after the first coat of paint dries. Then put on a second coat. For the best results, the edges of the hole you are fixing must be smooth before you apply the tape. If bits of plaster or drywall facing paper protrude forward, sand or slice them down before you apply the tape. Any bumps or high spots will telegraph through.

Conventional patching: If you are faced with a hole too big for these iron-on patches, or if you’d just rather have an honest-to-goodness solid patch, there are a couple of ways to get the job done. Both use a piece of ordinary drywall as a patch.With either technique, start by using a keyhole saw to trim the hole to a neat rectangular shape. This will make it easy to fit your patch.

Once you have the hole cut, you have two ways to go:

1. Cut a patch of drywall material about four inches larger overall than the hole. Turn the patch face down, and on the center of its rear surface, draw the outline of the hole. Next, take a razor knife and cut through the backing paper of the patch along the lines you have drawn. Break the patch along all four of these score lines. Then peel away the gypsum board around the edges of your patch, being careful to leave the face paper intact. What you want to do is create a patch with a flange of facing paper two inches wide all around it.

With the patch still face down, sand off any bits of gypsum still clinging to the back of the paper flange. Then slip your patch into position and check it for fit. If it’s too snug, cut off a bit more gypsum. When the patch will fit, take a six-inch putty knife and put a coat of wallboard compound all around the perimeter of the hole. Slip the patch into place and press its flange down all around the hole using your wallboard knife. Then use your knife to apply a thin coat of compound over the paper flange and put into the wall around your patch.

Let this coat dry. Then apply another coat with a 10- or 12-inch knife, feathering it smoothly out into the surrounding wall. Let that coat dry and, if necessary, apply a third. Shine a light at a low angle across the repair. This will reveal any imperfections. Sand them out with 120 paper on a sanding block, or apply another coat of compound.

When you are satisfied, paint it and the job is done.

2. The other solid patching technique requires two pieces of wallboard. One is the patch itself, the other is a backer to support the patch.

Cut the backer of gypsum board, about two inches larger than your rectangular hole. Punch two holes in the center of this backer, and tie a four-inch loop of string through them.Put some glue (I like a fast-setting epoxy) around the edges of the face of this backer. Slip it into the wall through the hole (hold onto that loop of string) and then pull it forward against the back of the wall. Twist it to align properly with the hole. Then slip a stick through the loop and twist the loop around and around, like a tourniquet, until it becomes tight and holds the backer in position.

After the glue sets, remove the stick and the string. Then cut a nice-fitting patch of wallboard. Put some glue on its rear surface, and glue it in place in front of the backer. Apply drywall tape around the edges of the patch. I like the new, self-adhesive fiberglass wallboard tape. It’s easy to apply, strong, and gives a smoother repair than old-fashioned paper tape.

After the tape is in place, trowel on a coat of wallboard compound and finish as described above.Which of these two techniques is best? Well, the second is stronger and a bit easier to feather out. But the first one has advantages, too. Since the patch hangs on the front of the wall, the patch material needn’t be the same thickness as the rest of the wall. If you happen to have a scrap of 3/8-inch wallboard on hand, you can use it to patch 3/8-inch wallboard, half-inch wallboard, or plaster of any thickness. I’d probably use the first technique on a plaster wall, and the second on a wall made with gypsum board.