How to Lay a Brick Hearth

Check with your building department for specific regulations and codes that govern the requirements relating to fireplace and hearth construction in your area. Contact your insurance company to determine whether it requires any specific techniques or materials during the installation of your new hearth.

Remove the old hearth or the existing flooring to allow for the amount of space required by the building code in your area. Install an approved cement underlayment board over the cleared surface.

Experiment with your brick pattern by laying the bricks over the surface of your cement underlayment. Try running them in lines, crosses or herringbones. Leave about a quarter-inch gap between the bricks. Take a picture of your preferred pattern to help you remember the placement. Remove the bricks and sweep any dust and particles from the cement underlayment board.

Build a temporary frame for your bricks by attaching 2-by-2-inch pieces of lumber into a frame around the perimeter of your cement underlayment board.

Spread a large piece of plastic sheeting over the surrounding flooring to protect it from any mortar dribbles.

Mix your mortar in a 5-gallon bucket according to the package instructions. Spread a three-quarter-inch layer of mortar over the cement underlayment board with the trowel. Press the bottoms of the bricks into the damp mortar, according to your chosen pattern. Wiggle and press firmly to seat the bricks properly in the mortar bed.

Scrape the damp mortar into the joints between the bricks. Use a dowel to press the mortar evenly between the gaps. Smooth the surface over the joints with a concave jointer. Wipe away any excess mortar while it is still damp.

Take off the temporary frame and allow the hearth to dry completely. Finish the bare edges around thecured hearth with a decorative molding or mosaic tile trim.