How to Lay a Cement Board Tile Floor
- 1). Set a sheet of cement board in corner of the floor. Use your pencil to trace around the perimeter. Pick up the board. Lay a layer of thinset mortar inside the lines you drew, using a notched trowel.
- 2). Press the board back down into the mortar. Secure it by driving in screws every six inches over the whole board with your screw gun.
- 3). Repeat for additional sheets of cement board, laying them end to end in staggered rows (so there are no four-way intersections). Use a jig saw to cut the pieces at the ends to fit.
- 4). Press mesh drywall tape over the seams between the boards. Spread thinset mortar on the tape with a drywall knife, smooth and flatten. Let set for a day.
- 5). Use your chalk snap-line to lay two intersecting lines over the middle of the floor, from wall to wall in both directions, so the floor is divided into four squares.
- 6). Use your notched trowel to spread thinset mortar over the center of the floor, covering the intersection of the two chalk lines in a wide enough area to encompass four tiles. Put tile spacers between them as you lay them.
- 7). Spread additional mortar and press more tiles into place, working your way out along the lines toward the walls. Tile the whole floor in a grid pattern, cutting the tiles by the walls as necessary, on your score-and-snap tile cutter.
- 8). Let the mortar set overnight, then pull out the spacers. Grout the floor, pressing the grout into the joints with your grout trowel and wiping of the excess with a damp sponge.
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