Flexable grout on wooden floor

[daveturnbull]

I am tiling my bathroom floor, i put 5.5mm plywood down but thought it was thick enough so put more 5.5mm plywood on top of the other plywood. Anyway i have since tiled my floor using flexable adhersive, however i cant find flexable white grout anywhere. Can i therefore use normal grout on the floor? I am worried as there is still so movement when walking on the floor.

 

[jefoss]

there are flexi grouts available dude, if you really cant find any you can also use a flexi additive, adflex being one. all good tile shops and the site ones should have some.

 

[daveturnbull]

Thanks for your help, i found flexible grout but just not white, i will try other shops etc as i dont want to end up re grouting because it starts cracking.

Thanks again

 

[lancenotalot]

Even a flexible grout may crack if there is too much movement in the floor,getting the floor as rigid as possible before tiling is the key to a long lasting job.
What size are your grout joints?

 

[daveturnbull]

They are 5mm, I am starting to think i should have screwwd the plywood down in more places. i screwed it every 6 inches around the edge but only in the middle i places if i felt some bounce.

 

[lancenotalot]

Screwing down at 200mm centres is normally advised so where you have done it at 6inches should be fine (about 150mm)
The fact that you have only used 5.5mm ply is more of a problem,12mm is advised (15mm by some adhesive manufacturers)

Not really sure where you can go from here,suppose the best advice would be change the ply for 12mm.
You could go ahead and put down the grout but the chances are it will crack.

 

[daveturnbull]

I was advised by a tiler 5.5mm ply would be fine, when i put it down i did not think it was good enough so i put more 5.5mm on top. Therefore the total is 11mm, or will it now be as good having 2 separate sheets of ply.

I surpose I have to give it a go a grout it.