How To Lay Backer Board For Floor Tile

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.

How to lay backer board for floor tile.

The backer board comes in different sizes and you will pick the right one depending on the type of floor you are installing. First changes in humidity make solid wood shrink swell and cup more than plywood. Lay the backer board according to the manufacturer s instructions. Never install new tiles over existing tiles or onto an unprotected wood or plywood floor.

Spread the mortar to about 3 16 thickness. Whenever you re laying tile on a wood subfloor you need to first install cement backerboard to prevent leaks and water damage. Using a notched trowel apply a leveling bed of thinset mortar over the subfloor and embed the backer board sheets into the adhesive. Can i fill the trench with thinset when i m thinsetting the board on or does it need to be done in advance of that.

I have 3 questions. Add more mortar as necessary to fill sunken areas in. Whichever backing board you decide to go for you ll need to measure it and cut it to size to ensure it fits the floor area you re planning to cover. Floor tiles should be installed over smooth flat surfaces.

Second the strength of wood boards isn t always consistent. Installing backer board involves three main steps. Unlike wood or drywall sub surfaces cement backerboard will not rot warp or grow mold and mildew when exposed to water. I m laying 1 2 cement board over ply and there s 1 5 2 trench around the perimeter of the ply old bathroom in a bar trench depth varies from 1 2 to 1 5 and the cement board will lay over it.

It s best to start in an open corner and work your way across the room cutting the more awkward pieces of board last to fit the opposite wall as you go. 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. According to backer board manufacturers and tile setters installing backer board directly over an old solid wood subfloor is risky for a couple of reasons.