Thinset Under Hardibacker Floor

Spread thinset over a seam between backer board sheets with the short flat edge of the trowel.

Thinset under hardibacker floor. Ridge the mortar with the notched side of the trowel. The amount of thinset you need is calculated by the square footage of the floor or wall the size of the tile and the size of notched trowel you use to spread it. Thinset mortar is commonly used for setting ceramic tile. Thin set dries slowly allowing you to fix and readjust backerboard sheets as needed.

Different size tile requires that you use a specific size trowel. I also will be tiling the bathroom floor with a 6 24 porcelain over shuluter ditra. Lay alkali resistant fiberglass mesh tape on the thinset and cut the end of the tape with a utility. Thinset under backer board.

A friend is helping us install a small 50 sq ft slate tile floor in a bathroom. I just finished a job where the original installer used a 3 16 v notch trowel to install the thinset under the backboard. Yes it is needed unmodified is fine for this it s there to fill any voids if the floor is out of level this should be fixed after the board is down thinset under the boards won t help there the boards will follow. The floor failed too much cush.

With the smooth side of a 1 4 inch notched trowel spread enough mortar for one sheet. The floor underneath is plywood at least 1 5 inches of it. The reality is that the installation instructions supplied by the manufacturers of hardibacker do require you to apply a supporting bed of mortar or modified thinset to the subfloor underneath the 1 4 sheets. The shower walls are a 4 12 subway tile.

My question is should i use a glass thin set on the pan and a different modified thin set on the walls. I hope to use the allset thin set there if i can find it locally. Typically a 1 4 x 1 4 x 1 4 square notch or u notched trowel is the requirement. You will be taking up the floor down to the floor joists if you ever want to remodel.

If you have ever tried removing thin set installed backer board then you will know why. He cut and screwed down all the hardibacker with no thinset under the hardibacker and no 1 8 joints where the harbibacker seams meet. Just screw down and tape joints like manufacturer recommends. It s a very small shower area 30 60.

It is also used to set porcelain tile and natural stone tile. Use thin set mortar when installing cement backerboard.