tile substrate

[garth77]

Hi, i'm looking to tile my bathroom floor with 600mm porcelain tiles. The floor is 16mm T&G. Any advice on what i should lay under the tiles?

I've done a bit of research and was leaning towards one of the cement boards like no more ply, but when i visited a tile shop they recommended schluter ditrs matting straight onto the floor (not sure the floor would be flat enough for this?). To confuse me further, a family member has had his whole ground floor tiled with similar tiles using
9mm multipro board. This stuff is cheaper but seems more for wall tiles? what would be the preferred option for this type of floor?

 

[Sean SML Tiling]

Go for a hardie backer cement board glued amd screwed every 200mm is there any deflection in the floor?

 

[Rich Midge]

If the floor is twisted, my advise would be to make sure the boards are firmly fixed to the joists. Prime with a neat coat, fit an anti fracture membrane (durabase, ditra etc) with an s2 then slc over. Other than that, is it worth taking up the t&g and starting from scratch. Extra noggins, packers on the joists to level the floor etc

 

[garth77]

The floor has a slight spring, but screwing the boards should sort that. It has one or two slight deviations which is why I thought of the boards rather than matting. I'm showing my ignorance here but what is s2 and slc?

 

[Andy Tiler]

If the floor is twisted, my advise would be to make sure the boards are firmly fixed to the joists. Prime with a neat coat, fit an anti fracture membrane (durabase, ditra etc) with an s2 then slc over. Other than that, is it worth taking up the t&g and starting from scratch. Extra noggins, packers on the joists to level the floor etc

I would always apply self levelling compound first then put a de coupling matt on top! Unless your using mosaic?If needed?if your unsure call Schluter uk!

 

[Rich Midge]

S2 is highly deformable flexible adhesive. Slc-self levelling compound. As Andy mentioned above, you could apply slc first then fit the mat. Slc onto t&g boards is not something I'd be keen on doing, they have a tendency to expand, contract and twist. But saying that, if there's a decoupler going on top, that'll take up any lateral movement.