Last Updated on April 11, 2023 by Dave Farquhar
If you cut a drywall outlet hole too big, don’t fret. It’s easier to fix than it seems. You even have a couple of different options.
Fix a too-big drywall outlet hole with tape and mud
You can fix a too-big drywall outlet hole with just some drywall mud and some tape. I use pre-mixed mud for this. If you mix up your own mud from powder, you want to mix it up nice and stiff. Closer to the consistency of mashed potatoes than to pancake batter.
Turn off the power to the outlet to be on the safe side. Then, using a 1-inch putty knife, glom some of that stiff drywall mud into the opening, starting from the edge and working your way down toward the outlet. The mud sticks pretty readily to itself and to the drywall, so the main thing to concern yourself with is getting a generous amount into the gap you need to fill. Then come back with a 2-inch knife and smooth it flush with the wall.
What you do next depends on how brave you are. You can apply tape now, and probably get a nicer result, but at the risk of messing it up. Or you can let it dry overnight. The next day, apply a bit of drywall tape over the wall for strength.
Apply one more coat of mud the next day over the tape and feather it out. You may need follow up by sanding it and applying additional coats of mud to get it to look good.
Patch a too-big outlet hole with more drywall
If you don’t want to mess with mud, you can patch the hole with more drywall. Cut a right-sized opening in a scrap of drywall a couple of inches bigger in all directions than your oversized hole. Then flip the piece over and trace an outline about an inch from the edge. Score along the lines with a utility knife. Then break along the line you scored and break off that inch or so of drywall from the edge. Now you should have a piece of drywall with about an inch of paper backing all around it.
Trace your patch over the hole with a pencil, then cut it out with a drywall saw. Insert your patch, then trace the paper backing around the area. Cut along your line with a utility knife, then peel away the paper. Now you can place your patch in the hole and secure it with carpenter’s wood glue. Glue both the gypsum wallboard and the paper.
Once the patch dries, fill in any small gaps that remain with a small quantity of drywall mud or spackle. Using this method, you can get a nearly invisible repair once you paint.
A trick if the outlet hole in your drywall is only slightly too big
What if you did a better job of cutting the outlet hole than I did in the example in the photo above, and your outlet hole is just slightly bigger than it needs to be? There’s a quick fix available if you’re willing to use a different outlet and don’t mind it being tamper resistant. The main selling point of the Leviton Decora Edge outlet, which costs around $3.50, is its push-in connectors with levers to secure the wires that make it possible to wire in about a minute. But the other feature it has is an oversized plastic strap with break-off fins that give you some extra leeway with the size of the outlet hole. Leave the fins and use a midway or jumbo size wallplate, rather than a standard wallplate, and you may be able to get the outlet to fit securely into the oversized drywall hole without doing any drywall work.
David Farquhar is a computer security professional, entrepreneur, and author. He started his career as a part-time computer technician in 1994, worked his way up to system administrator by 1997, and has specialized in vulnerability management since 2013. He invests in real estate on the side and his hobbies include O gauge trains, baseball cards, and retro computers and video games. A University of Missouri graduate, he holds CISSP and Security+ certifications. He lives in St. Louis with his family.