Second the strength of wood boards isn t always consistent.
Installing backer board on floor for tiling.
Install a cement based backer board following the manufacturer s instructions.
Thick 3 x 5 ft.
Whenever you re laying tile on a wood subfloor you need to first install cement backerboard to prevent leaks and water damage.
First changes in humidity make solid wood shrink swell and cup more than plywood.
Installations for floor tile and other horizontal surfaces like countertops require an extra step of applying thin set tile adhesive to the wood subfloor before laying down the cement board sheets.
How to install tile backer board.
Spread the mortar to about 3 16 thickness.
This provides a solid surface under the tile that prevents flexing that could lead to cracking.
For flooring the backer board should be installed over a 5 8 inch thick osb or plywood base.
Cement board commonly sold under trade names such as durock hardiebacker and wonderboard is now the standard underlayment used for ceramic porcelain or stone tile laid with thinset mortar adhesive cement board is used for most floor tile and has all but replaced plywood and drywall backer materials for wall tile applications in wet areas like showers and tub surrounds.
To install ceramic tile over wood the wood surface must be structurally sound enough to support the weight of the tile.
For countertops use 3 4 inch plywood beneath the backer board.
Half inch cement backer board is ideal for most tiling jobs including walls floors countertops and ceilings.
Unlike wood or drywall sub surfaces cement backerboard will not rot warp or grow mold and mildew when exposed to water.
Installation of cement backerboard is always preceded by application of thinset mortar which fills low spots in the subfloor and anchors the backer board sheets.
Use a polymer modified thin set a type of mortar to attach the backer board to the subfloor.
Add more mortar as necessary to fill sunken areas in.
It s typically available in 1 2 in.
Installing backer board involves three main steps.
Cutting fastening and taping and mudding.
Its made from cement and sand and is reinforced by fiberglass mats on both sides so it s impervious to water.
Never install new tiles over existing tiles or onto an unprotected wood or plywood floor.
Installing over wood.
Chipboard cushioned vinyl flooring particle boards of any type oriented strand board osb interior grade plywood tongue and groove planking and hardwood floors are unsuitable substrates for direct installation of ceramic tile.
Cement board is the most durable trouble free tile backer for tub surrounds showers floors and all other wet areas.
Using a notched trowel apply a leveling bed of thinset mortar over the subfloor and embed the backer board sheets into the adhesive.