When you plug something in and pull it back out, does it feel like the whole outlet box is going to come with you? Most likely the outlet boxes are loose because the ‘thin’ sheetrock has cracked or broken away. Here’s how to snug-up those outlet boxes for good.
Your box may look a bit different than this box, but most of them have the same concept. First, shut off the electricity and remove the cover. The cover will either have a screw or just snap off. Then completely loosen the box from the wall by unscrewing the top right and bottom left screws. Only turn these screws about 5 to 6 turns.
Carefully pull the outlet box out of the wall. Hopefully, you shouldn’t have to disconnect any wiring. Notice the little blue tab on the upper right. This is a built-in clamp that holds the box to the wall when the screw is tightened. You also have a clamp on the lower left. The sheetrock has probably broken away from this tab, so it has nothing to grab therefore making the box loose. Continue reversing the screw until the tab is situated at the very back of the screw. Do not unscrew so much that the tab falls off.
The trick to fixing the outlet is to put some support pieces behind the wall for the clamp on the outlet to snug-up too. Wooden shims work good for support pieces. Notice the layout of the shims in the picture. This is the layout you want, but the shims will be behind the wall.
Stick the shims thru the opening and position on the top and bottom edge of the opening. To make them stay until you can get the electrical box repositioned and tightened, I like to tape the bottom shim in place. The top shim is a bit more tricky. One trick is to put a dab of caulk on each end of the shim and stick up in place. If your electrical box has several wires coming in and out, positioning the shims may prove difficult. You may have to disconnect some of the wiring to get the shims in place.
Once snug and tight (don’t over tighten), screw or snap the cover back on. Notice on this picture that you can still see where the sheetrock was broken. To hide that, purchase an oversize outlet cover.