How to build a tile hearth for a fireplace
A tile hearth protects the flooring surrounding the fireplace from heat and ashes and provides a functional accent to any room. Tile makes an excellent material for a hearth because both the tile and the thinset mortar adhesive tend to hold up well to the heat from the fireplace.
Many types of tile do well in high heat, but it is important to talk to a tile professional when purchasing your tile. Raised tile hearths provide a place for homeowners to sit around the fire and help to keep things away from the fire itself. On the other hand, tiling a flat hearth is easier and may be more practical if your fireplace does not already have a raised hearth.
Determine how large the tile hearth is going to be. It should be large enough to catch any hot embers that may "jump" out of the fireplace, but not too large for the room. Measure the space for hearth with a measuring tape. Transfer the measurements to the floor by outlining the space with masking tape.
Remove carpet or laminate flooring from the area surrounding your fireplace with a hammer and pry bar. You should try to get down to the wood sub floor for proper installation of your tile hearth. If you have wood floors you may be able to build the flat hearth directly on top of the flooring. Remove all of the carpet padding, tack strips, and staples from the floor with a hammer.
Measure the area of the hearth and transfer the measurements to a sheet of cement backer board. Use a utility knife to cut the backer board to size.
Apply construction adhesive with a caulk gun to the back of the cement backer board in an "s" shape. Glue the backer board down and screw it into place on the subfloor.
Lay out the tiles on top of the hearth in a pleasing arrangement using tile spacers as needed. Use a tile saw to cut any edge tiles that need to be cut. Mark a starting point for the layout and remove the tiles and tile spacers from the backer board.
Mix the thin set mortar, following the label directions. Use a notched trowel to lay the mortar into place on the backer board.
Press the tiles into place on the cement backer board, beginning at your marked starting point and aligned with tile spacers. The thinset mortar should be allowed to dry for 24 hours.
Mix the grout according to the label directions. Apply the grout to the tile joints. Use a rubber grout float to squish the grout between the tiles. Wipe away the extra grout from the tiles with a sponge. Allow grout to dry 48 hours before use.