The primary benefit of cement board is that it doesn t break down or expand or warp if it gets wet.
Board for under tile.
This is not true.
But with many non organic shower backer boards available as alternatives there is little reason to use greenboard.
Use a polymer modified thin set a type of mortar to attach the backer board to the subfloor.
This is the industry standard most preferred by construction pros when installing ceramic or porcelain tile backer board comes in four foot by eight foot and three foot by five.
Here s how to choose the best tile backer board for your project.
Whenever you re laying tile on a wood subfloor you need to first install cement backerboard to prevent leaks and water damage.
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.
Only mix as much thin set as you can use in a half hour and be sure to have solid support under each tile.
Some homeowners believe that painting or priming plywood will render it suitable to use as shower tub backer board.
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.
This provides a solid surface under the tile that prevents flexing that could lead to cracking.
Thickness offers strength cement boards generally come in 1 4 inch 1 2 inch and 5 8 inch thicknesses.
The polymer modified thin set provides additional strength and helps eliminate any movement between the backer board and the subfloor.
Cement board is a type of underlayment that is now standard for most tile installations but particularly for floor tile.
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.
This is a distinct advantage over plywood and drywall.
Plywood alone cannot be used as a substrate under tile in showers.
Cement board also provides an additional layer over a plywood or particleboard subfloor adding stiffness to the tile.
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.
Unlike wood or drywall sub surfaces cement backerboard will not rot warp or grow mold and mildew when exposed to water.
If you use a too thin cement board it won t successfully support the tile s weight.
Never install new tiles over existing tiles or onto an unprotected wood or plywood floor.
If you follow all these steps you ll have a stiff monolithic crack free floor.