Dear Mr. Electrician: How do I fix a broken outlet box screw hole?
Answer: To fix a broken outlet box screw hole I usually replace the electrical box with an old work plastic electrical box. However other options have come out that changes the fixing method in some cases. NOTE: Some links below go to applicable products on Amazon and EBay. As an Amazon Associate I earn from qualifying purchases.
Below are photos and details of how I replaced an outlet box with a broken screw hole in a kitchen backsplash with ceramic tile.
BROKEN OUTLET BOX SCREW HOLE REPAIR
There is a product now available that would have made the replacement of the existing electrical box unnecessary. I haven’t used it yet, but it seems to be an easy fix to a broken screw hole. Take a look at the G-Clip for a simple plastic outlet box screw hole repair.
There are not a lot of options for repairing a broken screw hole on a plastic electrical box. My standard choice was to replace the electrical box. The G-Clip gives me an option to repair if possible. Sometimes the electrical box is broken more than just the screw hole so it would need replacing.
REPLACE THE BROKEN BOX

The bottom screw hole on the above outlet box is clearly broken off. Because of the way these plastic boxes are constructed there isn’t any material left behind to screw into.

I usually use a large old flat head screwdriver to pry outlet boxes away from the wall stud. They tend to pop out easily.

I use my Knipex High Leverage Diagonal Pliers to cut the screws on the outlet box in the wall.

The existing opening in the wall was a little too small to remove the old broken outlet box so I just let it drop inside of the wall.

I used my RotoZip rotary power tool with a tile cutting bit to enlarge the outlet box opening enough for me to get the new outlet box in the wall. It was made more difficult because the wood stud in the wall was a little twisted.
I had to make the opening in the tile larger than I normally would have so I could squeeze the new outlet box into the wall. Fortunately I have a collection of tile cutting bits for jobs like this. My RotoZip also has a small circular saw attachment for cutting wood, metal, or tile with the appropriate blade.

I put some electrical tape around the outer jacket of the cable in the wall because the wire clamps in the box would be pushing against the wires.
Above is the newly installed old work plastic outlet box that replaced an outlet box with a broken screw hole. The new old work outlet box is installed with the existing wiring which is a little short.

I spliced the wires together by twisting them with my linesman pliers, and twisted pigtails on the ends. A screwed-on wire connector finishes it.

I folded the wires into the back of the old work outlet box and trimmed back the pigtails for the new GFCI receptacle to be installed. Most electrical receptacles in a home must now be tamper resistant.

A new GFCI electrical receptacle attached to the pigtails.

The ears on the GFCI electrical receptacle have been cut off so that the receptacle fits nicely into the notch on the old work outlet box.

Click here to see more blog posts of mine about switch and outlet boxes.
My blog post about grounding outlets and switches may be of interest to you.
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