Install 4 Cement Boards To Be Screwed To Sub Floor

Add a layer of 1 2 in.

Install 4 cement boards to be screwed to sub floor.

Would this calculation get me to the right height compressed thin set on top of sub floor 1 8 cement board 1 2 compressed thin set on top of cement board 1 8. Cement boards that some in sheets. Cement backerboard is a thin layer of concrete with fiberglass mesh on both sides. Fasten the cement board sheet to the subfloor with 1 1 4 inch cement board screws.

Bc plywood over the old subfloor using construction adhesive and driving 1 1 4 in. Screws every 6 in. As long as the subfloor is 3 4 in. Here s the right way to attach cement backer board to a plywood subfloor.

It s available in sheets of many sizes with 3 foot by 5 foot sheets being the most common. Structural panel concrete subfloor. Vinyl flooring glued over 1 4 in. Screw the old floorboards to joists with 2 in.

For ceramic tile floors the cement board usually rests on a plywood subfloor minimum 5 8 inch thick exterior grade plywood or osb if new ceramic tile is being laid on an existing floor the cement board can usually be laid right over the existing floor finish provided it is in good shape and the extra floor thickness is not a problem. I need to match the height of the existing tile in the bathroom. When installing a ceramic tile floor on a concrete subfloor you don t have to worry about flexing as long as the concrete slab is at least 1 1 8 inch thick which most slabs are. If the subfloor doesn t have enough stability you can usually but not always remedy the situation by installing cement backer board also called cementboard.

I plan on thinsetting and screwing cement board to the subfloor then redgard then thin set and tile. Don t use regular drywall or wood screws which corrode in cement board. Thick cement board instead of the usual 1 2 in. These are specially coated corrosion resistant screws that have notches under their heads that help the screws burrow into the board so the heads sit flush with the panel.

Place the screws no more than 3 in. See code reports below. Durable non combustible concrete subfloor panels offering fast installation structural stability and 1 and 2 hour fire rated assemblies. Tongue and groove material screw the underlayment down right through the vinyl with 1 1 4 in.

While using 1 4 thick rather than 1 2 thick cement backer board is acceptable how you install the backer board and attach it to the plywood subfloor is as important as how you lay the tile on top of it. Screws have better hold down power than nails and will help prevent boards from loosening or cupping.