Patching Large Drywall Holes: Three Methods That Actually Work

Published December 27, 2024 by Mike Sullivan

Key Takeaways

  • Holes 4-8 inches work well with the California patch method using the drywall edges as backing
  • Holes over 8 inches usually need backer boards or blocking installed before patching
  • Stud-to-stud replacement is best for damage larger than about 12 inches
  • Setting compound is stronger than regular mud for large patches
  • Prime the entire patched area to prevent flashing when painting

The first large hole I ever patched was in my son's bedroom. He was 14, had a disagreement with his closet door, and the door won. Or lost, depending on your perspective. Either way, I had a fist-sized hole in the drywall and a teenager who was very sorry and also grounded.

I stood there looking at that hole with no idea how to fix it. Small patches I could handle. This was different. There was nothing behind it to attach a patch to, just empty wall cavity with electrical wire running past.

Called my uncle, as I do for most home repair questions. He walked me through the California patch method over the phone. Took me about two hours including dry time, and honestly, it looked pretty good. You can still see it if you know where to look, but strangers wouldn't notice.

Since then I've patched probably a dozen large holes in various houses, using different methods depending on the size and location. They're all doable. Just takes the right technique for the situation.

Choosing Your Method

The size of the hole determines the repair method. There's overlap in the ranges, so use your judgment on borderline cases.

Holes 3-6 inches: California patch. Uses the paper facing of the patch drywall as its own backing. Quick and elegant.

Holes 6-12 inches: Backer board method. You install strips of wood or drywall behind the existing wall to give the patch something to screw to.

Holes over 12 inches or multiple holes close together: Stud-to-stud replacement. Cut back to the nearest studs on each side and install a proper piece of drywall.

The methods aren't exclusive. I've done California patches on 8-inch holes and backer boards on 4-inch holes. It depends on the situation, the shape of the hole, and honestly how confident you're feeling that day.

The California Patch

This is my favorite method for medium holes because it's clever. The patch creates its own backing.

Step 1: Square Up the Hole

Use a drywall saw to cut the damaged area into a neat rectangle or square. Doesn't need to be perfectly square, but straight edges make the patch easier. Remove any loose material.

Step 2: Cut the Patch

Cut a piece of drywall about 2 inches larger than the hole in both directions. So for a 4-inch hole, cut a 6-inch square patch.

Flip the patch over. On the back side, score the drywall about 1 inch in from each edge. Score through the paper and into the gypsum, but not through the face paper.

Snap off the outer inch of gypsum on all four sides. What you're left with is a center section that fits the hole, with a 1-inch paper flap extending on all sides. The paper flap becomes your tape.

Step 3: Set the Patch

Apply a thin layer of joint compound around the hole on the existing wall. Press the patch into place, with the gypsum core fitting into the hole and the paper flaps laying flat against the surrounding wall.

Smooth out the paper flaps, pressing them into the compound. Use a 6-inch knife to work out any air bubbles. Add compound over the paper edges and smooth, feathering out a few inches.

Let it dry completely. This takes longer than small patches because there's more compound. Give it at least 4-6 hours or overnight.

Step 4: Second and Third Coats

Apply additional coats, feathering wider each time. Two to three coats is typical. Sand between coats once dry. The goal is a smooth surface with no visible edges from the patch or paper.

The Backer Board Method

For larger holes where the California patch isn't practical, you need to install backing for the patch to screw into.

Step 1: Clean Up the Hole

Cut the damaged area into a rectangle with clean edges. Remove loose material. If there's a stud visible at one edge of the hole, great, that's one side of backing already done.

Step 2: Install Backing

Cut strips of 1x3 or 1x4 lumber about 4-6 inches longer than the hole opening. Slip a strip behind the drywall so it overlaps the hole by at least an inch on each end.

While holding it in position, drive drywall screws through the existing wall into the strip. Put screws about an inch from the edge of the hole, where the patch will overlap. You need at least two screws on each end to hold the strip firmly.

Install strips on the top and bottom of the hole. For very large holes, add a strip or two in the middle as well so the patch isn't spanning too far without support.

Step 3: Install the Patch

Cut a piece of drywall to fit the hole with about 1/8 inch gap on all sides. Hold it in place and drive drywall screws through the patch into the backing strips. Space screws every 6-8 inches.

The small gap around the edges will be filled with compound. Don't try to cut a tight-fitting patch because you'll never get it in cleanly.

Step 4: Tape and Mud

Apply paper tape over all the seams, bedding it in joint compound. Build up with additional coats, feathering out 6-8 inches. A large patch might need 3-4 coats to blend properly.

This is where patience matters. Rushing the coats or not feathering enough will leave you with a visible patch. Take your time and it'll be invisible.

Stud-to-Stud Replacement

For very large holes or areas with multiple holes, it's easier to cut back to the studs and install a proper piece of drywall.

Use a stud finder to locate the studs on either side of the damage. Mark lines down the center of each stud. Cut along these lines with a drywall saw or utility knife.

Cut the top and bottom of the section between studs. Remove the damaged piece. You now have an opening with stud edges on both sides to screw into.

Cut your patch to fit, leaving about 1/8 inch gap. Screw into both studs, spacing screws about 12 inches. Tape all four seams and mud as usual.

I've done this for holes ranging from a foot square to entire 4x8 sheets. The process is the same, just scaled up. For full sheets, you'll want a helper to hold the drywall while you screw.

What About Wires and Pipes

That first hole I patched had an electrical wire running right through the middle of the wall cavity. This is common, especially in interior walls.

Don't panic. Just work around it. When cutting your patch or installing backing, leave space for the wires. The patch doesn't need to fill every inch of the cavity, it just needs to cover the hole in the wall surface.

What you absolutely don't want to do is nick a wire or pipe while cutting. Cut slowly, look into the cavity with a flashlight before each cut, and if you see anything, cut around it carefully.

My neighbor Maria hit a wire while cutting out a damaged section of drywall. Fortunately the circuit was off since she'd killed power while working. But if it hadn't been, that could have been bad. Always kill power to any circuits that might run through the wall you're cutting into. Check with a non-contact voltage tester to be sure.

Making Large Patches Invisible

Large patches are harder to hide than small ones because there's more area to blend. A few tips from patches that worked well and patches that didn't:

Feather way out. The edges of your mud should extend 8-12 inches from the patch, maybe more for really large repairs. Thin compound spread over a large area is less visible than thick compound over a small area.

Match the texture. If your walls have orange peel or knockdown texture, a smooth patch will be obvious. Texture the patched area to match before priming. Practice on cardboard first if you've never textured before.

Prime everything. The entire patched area needs primer, not just the compound but the surrounding wall too if you're repainting. This gives you a uniform base for paint.

Paint the whole wall. Touch-ups on large patches rarely blend perfectly. If you want the repair truly invisible, repaint the entire wall from corner to corner.

The closet door punch in my son's room? I did all of the above, and now I can only find the patch if I look closely in raking light. Everyone else just sees a wall.