Where to use s2 adhesive? - Tile Advice

[Macster]

I'm fitting limestone tiles 900x600 using keraquick over UFH with schluter ditra matting and reading the mixing ratio says about potentially using mapei latex to make it s2 when using large format tiles (over 600x600) but from my research I've only come across needing it to be S1. Is that because of the ditra etc where as s2 can be used for wooden floors?

Cheers

 

[Dave]

If its a solid substrate then s1 is fine. S2 is more for timber floors with minimal deflection or tiles that required S2 adhesive.

 

[Macster]

If its a solid substrate then s1 is fine. S2 is more for timber floors with minimal deflection or tiles that required S2 adhesive.

Ah OK mines 22mm caber board with the UFH grooves in with 5mm plywood and then schluter ditra so S1 should be right then? Thanks for the help btw

 

[Dave]

Ah OK mines 22mm caber board with the UFH grooves in with 5mm plywood and then schluter ditra so S1 should be right then? Thanks for the help btw

Why 5mm ply. ?

 

[Macster]

Ah OK mines 22mm caber board with the UFH grooves in with 5mm plywood and then schluter ditra so S1 should be right then? Thanks for the help btw

Think I've sorted it just second guessed myself because it says on the keraquick to use mapei latex if over 600x600. However on research schluter don't recommend s2 because it would be to deformable which is what I was thinking originally. If that's all still the correct information that is.

 

[Macster]

Why 5mm ply. ?

MI's stated I had to do It over the 22mm caber, it has grooves for the UFH so it won't be as strong so I suppose that's to reinforce it.

 

[Ben-gee]

Wouldn’t 6mm hardie be better than 5mm ply?