How to Hang a Mantel on a Dry Stack Fierplace Facade

Sand the non-assembled mantel pieces using medium-grit sandpaper to smooth their surfaces. If the mantel is only one piece, then sand its surfaces. Either apply one coat of primer and paint to the mantel or rub stain on it with a cloth.

Assemble the mantel, if necessary, according to the mantel manufacturer's instructions. Some mantels have leg pieces, and a mantel's dowels on the top of the legs must be slotted into the holes on the bottom of the mantel.

Place the mantel against the dry-stack fireplace facade, and reposition the mantel until it is centered around the firebox. Set a 3-foot long level on top of the mantel to ensure that it is level horizontally. If the mantel has legs, tap shims underneath each leg, if necessary, to make the mantel level.

Trace the outline of the mantel on the fireplace facade with a pencil.

Place the mantel flat on the floor or a work surface.

Measure the horizontal length of the mantel. Cut a piece of 2-by-4-inch wood to make it the same horizontal length as the mantel. The cut piece of wood will be the top cleat.

Place the top cleat just under the mantel shelf to ensure it is the same horizontal length or slightly shorter. It can't be longer than the mantel.

Position the top cleat horizontally on the back of the mantel, and then measure from the bottom of the top cleat to the bottom of each leg. Cut 2-by-4-inch wood to make two leg cleats that measurement.

Place the top cleat horizontally against the fireplace facade. Position it within the outline of the mantel you drew and in the exact location underneath the mantel shelf as it was positioned on the back of the mantel in the previous step. Use the level to ensure the mantel is level, or plumb.

Drive 1/2-inch deep pilot holes into the top cleat with a hammer drill that has a carbide drill bit. Fasten the top cleat to the facade by driving 3-inch long deck screws through the pilot holes and into stones in the dry stack. The deck screws must go into stones and not between two stones; the space between stones cannot hold the mantel.

Fasten the leg cleats to the facade in the same way you attached the top cleat.

Drive 2-inch long finish screws every 16 inches along the back of the mantel shelf into the top cleat with an electric drill. Also drive 2-inch long finish screws every 16 inches along the sides of the mantel legs into the leg cleats. Set the head of each screw below the surface of the mantel.

Smooth wood putty over the screw heads if you painted the mantel. Wipe away excess putty with a moist cloth, and then paint over the putty.