How to Make a Corbel Mantle

Move a stud finder over the fireplace. Mark the location of each stud with a vertical pencil line.

Lift your hollow-backed mantle to the wall. Center the mantle on the firebox and raise it to the height you want. Most jurisdictions require a mantle be at least 18 inches from the top edge of the firebox. Usually, a mantle is chest height. Mark the height you want.

Place a level on your height mark and draw a level horizontal line. Place your cleat over your horizontal line. A cleat is a board that inserts into the back hollow portion of the mantle. This cleat actually supports the mantle. Center your cleat.

Screw the cleat to the studs using long wood screws. Screw two screws at each stud mark.

Position the mantle over the cleat. Use the fasteners provided with the mantle and screw the top back edge of the mantle to the top of the cleat. Screw the bottom back edge of the mantle to the bottom of the cleat. Space your fasteners 8 to 12 inches apart.

Lift your corbel and place it in position 8 to 12 inches from the outside edge of the mantle. Mark the outline of the corbel on the wall. Center the corbel cleat inside the outlined area. Make sure the corbel will touch the bottom of the mantel when you calculate the height of the cleat. Secure the cleat to a wall stud using at least two screws per cleat. If no stud is available, insert wall anchors and secure the cleat with screws turned into anchors. Some will require more screws. Repeat for the second corbel.

Position the corbel over the cleat so that it is snug to the underside of the mantle. Remove the corbel and add construction adhesive to the top of the corbel. Press the corbel into position. Use the pre-drilled attachment holes to screw the corbel to the cleat. Repeat for the second corbel.