How to Install a Heavy Wood Mantel Shelf

Lay down a protective tarp to protect your flooring from the heavy wood. Place the mantel shelf top-down onto the tarp, exposing the holes for the legs.

Connect the legs to the mantel shelf. Most mantel kits include shelves and legs with pre-drilled holes and installed dowels. Lock the dowels securely in place.

Lift the mantel and place it against the wallt. Center it around your fireplace in the position in which you will install it.

Run a level against the wall to check for flatness, as well as front to back across the shelf. If necessary, install thin wooden shims between the legs and the floor to bring the surfaces level.

Trace the outline of the mantel's intended position against the wall in pencil. This will help you install the supports for the heavy wood.

Lift the mantel out of place and place it face-down and top-down on the tarp. Measure the width of the shelf from the inside and back with a tape measure and cut a two-by-four-inch piece of wood to this length with a circular saw or table saw. Fit the cleat into place on the inside of the shelf to check the fit.

Measure the length and depth of the legs from behind and cut two-by-four pieces to match these as well. Fit them inside the legs to check the fit. These two-by-four pieces, known as cleats, will provide extra support for the heavy mantel, taking some of the stress off of the wall and the screws that hold the mantel in place.

Hold the shelf cleat against the wall, inside the outline where it corresponds to the actual shelf position. Drill four ½-inch holes through the cleat, spaced evenly apart, with a carbide-tipped masonry drill bit. The holes should extend into the brick or wall of your fireplace.

Install 2½-inch long concrete screws into the pilot holes in the clea, using a drill. This will secure the top cleat to the wall. Repeat the process with the leg cleats as well to install all support pieces.

Lift the mantel and fit it into place over the cleats, lining it up with your outline on the wall. Press the mantel firmly against the wall and install 2-inch finishing screws into the mantel every 16 inches along the shelf. The screws will go into the cleat, securing the shelf in place.

Install finishing screws every 16 inches along the outer edges of the legs to secure the mantel to the leg cleats. This will secure the mantel in place.

Hammer thin pieces of molding and 4d finishing nails into place along the inner edge of the mantel if necessary to hide gaps between the leg pieces and the brick. Use filler putty to cover screw and nail holes.