How to Install a Cement Backer Board on the Floor
- 1). Lay a full piece of backer board in one corner of the floor. Run a pencil around the perimeter of the board.
- 2). Remove the backer board. Spread thinset mortar over the floor, within the marked space, using a mortar trowel. Set the board back down, pressing it into the mortar. Shoot galvanized screws into the board with the screw gun, one every square foot.
- 3). Set the next backer board along the end of the first one, with mortar and screws, as before. Repeat for each board, laying them across the floor in courses. Cut the end boards with a jigsaw as needed. Stagger the positions of the boards from course to course so there aren't any four-way intersections.
- 4). Lay mesh drywall tape on all the seams between the backer boards. Spread thinset mortar over the mesh tape, using a wide drywall knife. Get the mortar smooth and flat. Let it set for a day. The floor is ready for tiling.
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