Board For Under Tile

Tile is hard and will break or dislodge if the surface bends under the load and many wood surfaces can expand or contract negatively impacting their ability to stay level and support the weight.

Board for under tile.

If you must install over such surfaces it is best to install a backer board over the old surface and install the tile on the backer board. The primary benefit of cement board is that it doesn t break down or expand or warp if it gets wet. Whenever you re laying tile on a wood subfloor you need to first install cement backerboard to prevent leaks and water damage. Tile needs to be installed on a backer board to keep the assembly stiff otherwise the assembly will flex at the grout joints allowing water to seep behind the tile and rot the substructure.

If you use a too thin cement board it won t successfully support the tile s weight. Cement board is an easily installed diy tile underlayment providing a stable dependable tile setting substrate while eliminating the complicated lath and mortar floating process. Never install new tiles over existing tiles or onto an unprotected wood or plywood floor. The polymer modified thin set provides additional strength and helps eliminate any movement between the backer board and the subfloor.

Unlike wood or drywall sub surfaces cement backerboard will not rot warp or grow mold and mildew when exposed to water. Do it yourselfers can use either 1 2 or 1 4 inch cement board in certain applications while other scenarios mandate 1 2 inch board. This is not true. Plywood alone cannot be used as a substrate under tile in showers.

Lay the tile in thin set set the tiles using the same latex modified thin set and techniques used for the cement board. Doesn t deteriorate when wet. Some homeowners believe that painting or priming plywood will render it suitable to use as shower tub backer board. Use a polymer modified thin set a type of mortar to attach the backer board to the subfloor.

Cement board also provides an additional layer over a plywood or particleboard subfloor adding stiffness to the tile. But with many non organic shower backer boards available as alternatives there is little reason to use greenboard. This is a distinct advantage over plywood and drywall. Thickness offers strength cement boards generally come in 1 4 inch 1 2 inch and 5 8 inch thicknesses.

This provides a solid surface under the tile that prevents flexing that could lead to cracking. Here s how to choose the best tile backer board for your project. Only mix as much thin set as you can use in a half hour and be sure to have solid support under each tile.