Tile backer boards are just as important part of underfloor heating as the heating cables. Tile backer boards are foam insulation sheets with a re-enforced cement fascia to both sides, and their main job is to help block the heat generated from the heating cables from penetrating the sub-floor and reflect it upwards into the room.

Choosing the correct board is very easy. The more you have (the thicker it is) the better it is as you can never have “too much insulation. Tile backer boards are normally installed on top of the existing sub-floor.