Help please repairing floor

[Dave]

Are there columns or support walls under the joists , that is a large area , is it a single room ?

 

[J Sid]

Not really - the joists and underfloor heating

Could have said at start!

 

[Dumbo]

So is the buildup ply ufh ditra or ply ditra ufh

 

[J Sid]

Or under the ply?

Not all info again 😭

 

[Dave]

So is the buildup ply ufh ditra or ply ditra ufh

Or piped within the joists ??

 

[Joshjupp]

Or piped within the joists ??

Thats what I reckon pipe work in between the joists all sitting on top of insulation I looked at a big floor the other day and it was the same they are having wooden flooring instead of tiles now as I advised

 

[Storrs]

Sorry for not being clear - I’m a novice

bottom up Joist, with celotex between and then aluminium trays with pipes for UFH then ply, then ditra and finally tile. The floor is one big kitchen dinner and is approx 65m2. There is also brick support in the floor for joist etc. Thanks everyone for your help.

 

[Dumbo]

Sorry for not being clear - I’m a novice

bottom up Joist, with celotex between and then aluminium trays with pipes for UFH then ply, then ditra and finally tile. The floor is one big kitchen dinner and is approx 65m2. There is also brick support in the floor for joist etc. Thanks everyone for your help.

So what you described should not fail if done properly . Ply should be fixed securely and all joints supported. So either falling on a joist or a noggin.
Ditra should be stuck securely with coverage completely under the matting, then when installing the tiles all mat cavities should be filled prior to creating a rib bed on top and then tiles should be back skimmed and fixed to ensure full coverage but all of that is no good if you can feel the floor moving prior to tiling .

 

[J Sid]

You need to see if the tiles are stuck to the adhesive.
From what you said it is either fixer error or thermal shock imho
What expansion /movement joints are in the floor?
I take it the ply was fixed correctly, backs and edges sealed and 5mm gaps between boards filled with silicon