How to Make a Raised Brick Hearth

Nail together a frame in the shape of the hearth. Use sturdy, flame-retardant decking lumber for this project. The boards for the frame should be 2 inches thick and either 4 or 6 inches wide. Nail a grid of lumber inside the frame, placing the studs 16 inches apart. This will prevent the hearth from sagging later.

Cover the frame with a 2-inch plywood sheet cut to fit on top of the hearth. Apply adhesive caulk to the studs in the frame, then attach the plywood to the frame by screwing it into the frame.

Cut the cement board to fit on the top and sides of the frame. Glue down the cement boards with construction adhesive, then screw it into the frame. Countersink the screws, then fill any holes in the cement board with mortar so that the surface is level.

Lay your bricks over the surface of the hearth so you know ahead of time what the layout will be. There should be a 1/2-inch space in between bricks. As you remove the bricks from the hearth, number them with chalk on the back so you will know where they go.

Spread a layer of thin set over the hearth in the location of the first five or six bricks you plan to lay. Use a trowel to spread the thin set, then use the notched side of the trowel to cut grooves in the thin set.

Lay the first bricks on the thin set. Wiggle them a little and press them into the thin set so the thin set will seep into the pores of the brick. Leave a 1/2-inch space in between bricks, as you did in Step 4.

Apply more thin set to the hearth, then apply the next bricks on the hearth. Repeat this until the top of the hearth has been entirely covered by veneer.

Spread an area of thin set on the side of the hearth large enough for approximately five or six bricks, just as you did on the top. Use the notched side of the trowel to scrape grooves in the thin set, then attach bricks to the thin set. Repeat this until the entire side of the hearth has been covered with bricks. Wait for the thin set to cure.

Grout the joints between the bricks with mortar. Use a tuck point trowel.

Scrape off the excess mortar from the bricks, then press a jointer into the mortar to create a concave joint between the bricks.