Backer board on slab

[Christoph]

Currently there is vinyl tile in my bathroom. I just bought the house and some things were not done right by the previous owners. I want to put down ceramic tile and a backsplash in the bathroom. I don't think there is a subfloor/backer board under the vinyl tile as there's a gap between the tile and the vanity and it feels like that's the slab. What backer board would you all recommend and what's the process of installing one? My stepdad and I are new to this but he's done numerous other home repairs. So we feel we can do this. I've got about 1.5 in. from the current tile now up to the bottom of the door and about 1/4 in. from the tile up to the carpet in the hallway.

[HayZee518]

you'll need to take up a few tiles to see what is underneath. if the vinyl was glued directly to the concrete, ALL the tile will have to be removed and ALL the glue removed either by a solvent or grinding it off. once that is done you'll need to find "level" in all directions on the floor. low spots will need to be filled in with a concrete based floor leveler and concrete bonding agent. once this done, think about putting down an electric radiant heating coil as I'll almost bet the slab wasn't poured on a styrofoam base, so it'll be COLD! After that use your thinset directly over the coils or slab.

[pushkins]

I agree, all the old tile and glue will need to be removed (entirely) then the concrete cleaned and prepped with Bondcrete or the like before filling the lows with floor leveler. You cannot lay cement backer board over the top of the tile as you have no way to secure it to the concrete slab.
When removing the existing tiles get yourself a tile scrapper from Lowe's/Home Depot (they are in the flooring section) it will cost you $15 but will make the job 100% easier and much easier on your backs.

[Christoph]

It looks like there is some kind of backer board already under the vinyl. In the gap between the tile and the vanity, we can see a little bit of something. We're not sure if its wood or cement backer board. Right now we're putting ceramic tile on the wall and then do the floor. This is a first for both of us doing any kind of tile.

[pushkins]

Normally you do all the demo first then tile the floor then the walls, the wall tile should come down over the floor tile.

[ceramictilepro]

backer board is used for wood sub-floors. schluter ditra works way better imo

ceramictilepro