How to Repair Out-of-Square Cabinets

Open the cabinets and remove anything inside.

Place a level inside the cabinets to determine how far out of square they are. If using a spirit level, use the horizontal guide to check the amount of lean. With an electronic level, simply make a note of the readout.

Repair minor leans of 5 degrees or below by loosening the screws at the back of the cabinet to give yourself a little bit of play. Try removing any shims, if present, to see if that brings the cabinet square. If not, have an assistant gently raise the cabinets until they are even, according to the level. Secure in place by retightening the screws holding the cabinets to the wall.

Remove cabinets that are more than 5 degrees out of plumb by loosening the screws holding them in place. Place the cabinets on the floor. Have an assistant help you if the cabinets are heavy.

Secure the cabinets together to each other, if these are multiple cabinets. Use screws to connect the insides of the cabinets together. Close any gaps between the cabinet faces to give the cabinets a sleek and professional appearance.

Use a stud detector to locate the studs on the wall. Fastening the cabinets into the studs keeps the cabinets secure and square. Make a mark on the wall where the stud is, beneath the level of the cabinets, as a guide.

Lift the cabinets back up and onto the wall. Check that the cabinets are plumb, then drive screws with washers through the cabinet backs and into the studs with a power drill and screwdriver bit.

Make further adjustments by inserting shims under the cabinets. Secure by tightening the screws.