Two different floor sub but same level?

[yarwood]

Hi everone,

I have been a member for a while now, but any questions i have had i've been able to answer by looking through the mass of previous threads. Hope you don't mind!
I have got a floor to tile with limestone tiles, not sure what the customer has got yet. It is a ground floor room roughly 35 m2 without ufh. 2/3rd of the floor is an original concrete slab, the other 1/3 is a wooden floor. The joists are 450mm centres, and the chippy has screwed 18mm plyboard down. The hole floor area is now level.
The question is, where the two floors meet, do you think this will crack. What would be the best approch. Has anyone come across this before?
Any help would be great.

Many Thanks

Tim

 

[White Room]

Hi and welcome.....you will need an expansion joint where the 2 substrates meet....

 

[DHTiling]

Honest answer... 100% of the time it will crack every time.. but others on here have other ideas of using uncoupling membranes.. but these will only cope with so much expansion but will NOT cope with deflection, the smallest amount of downwards movement will eventually crack.

The choice is yours.

 

[peteablard]

Definitely run an expansion joint across it.....

 

[yarwood]

Thanks for quick replys,

This sounds like a conclusive answer. Ta The grout colour will be mapei 130 jasmin, can i get an expansion joint to match this colour?

Do you think that 18mm plyboard will be sufficient to tile ontop of, with limestone, or do i need to double ply?

Forgot to mention, the whole area will have a de-coupling membrane.

Thanks so much for all your help, experiance takes so long a gain.

 

[Spud]

Thanks for quick replys,

This sounds like a conclusive answer. Ta The grout colour will be mapei 130 jasmin, can i get an expansion joint to match this colour?

Do you think that 18mm plyboard will be sufficient to tile ontop of, with limestone, or do i need to double ply?

Forgot to mention, the whole area will have a de-coupling membrane.

Thanks so much for all your help, experiance takes so long a gain.

schluter dilex peach colour is the closest

 

[DHTiling]

Dural make any Mapei grout colour joints

 

[yarwood]

Thanks for your advice all.