How to Replace a Door on a Concrete Slab

Place wood shims between the bottom of the existing door and the concrete slab to support the door.

Remove the screws that attach the hinges to the door with a screwdriver. Remove the existing door.

Measure the distance between the top of the door frame and the concrete slab on both sides of the frame and the distance between the sides of the door frame. Measure the height and width of the new door. The door frame should provide at least a 1/4-inch clearance at the top and bottom of the new door.

Measure the distance between the concrete slab and the latch plate in the door frame.

Trim the top and bottom of the new door as needed with a table saw to provide a 1/4-inch clearance at the top and bottom of the door frame, ensuring that the distance between the bottom of the door and the latch is 1/4 inch shorter than the distance between the slab and the latch plate. If the concrete slab is uneven, you may need to trim the bottom of the door at an angle.

Place 1/4-inch wood shims on the floor in the doorway at 6-inch intervals. Set the new door on top of the wood shims. Mark the screw holes in the hinges on the edge of the door.

Drill pilot holes through the screw holes in the hinges and into the edge of the door.

Mark the edges of the hinge plates that attach to the door on both sides of the pilot holes, and score the marks with a utility knife. Use a hammer and a chisel to cut a mortise deep enough to accommodate the hinge plate. You may need to make several chisel cuts to obtain the proper depth.

Insert and tighten the hinge screws with a screwdriver. Remove the wood shims. Open and close the door to ensure that it functions properly.