cracks in new travertine floor: advice needed!

[Rich]

I cant beleive what ive been reading with regards to this floor from start to finish, Ive only been tiling 4 years and not done alot of natural work and am always learning from this site but id also say its a must for UFH and a natural tile to use a decoupler membrane and also correct adhesive and fixing mehod is a good start to. I regularly use keraflex only becase of its thick bed properties as in it can go upto 15mm thick and long pot life meaning im under no pressure.

Dont know if anyone would agree but maybe plying the floor over chipboard for additional strength (provent bounce) may have helped and then applying the membrane ontop of that (for lateral movement)therefore doing away with the cementboard as it provides no strengh properties and is only ther to gce a good tiling surface but you already will have an excellent surface to fix to with the decoupler and by fixing using a full bed method and ensuring 100% coverage, possibly even backbuttering tiles.

I would agree that a decoupler would have been a very good idea but the problem with using a membrane over ply or chipboard is that adhesive really doesnt bond well to these, a cement board is mechanically fixed. In an ideal world a cement board and then a decoupling membrane would be belt and braces but its getting people to pay for it. With regards to the fixing method, you have just raised another point. Trav MUST be back buttered and the voids in the back of the tiles filled with adhesive, I back butter all floor tiles to ensure a good coverage.

Dont think it is worth asking if the builder back filled/buttered the tiles.

 

[bugs183]

I know its going over old ground but it appears that there are two major problems here, the floor is flexing thus causing the straight line cracks, and the method of dot and dab as everyone says is a total no no, and even more so on travertine.
It was never going to work, if the builder becomes troublesome, just call the adhesive manufacturer in, they'll condem it and give you a full spec to fix the new floor with. Everyone has pice of mind then.
Sorry but does look like the kitchen and the floor needs to come up. If the builder plys and retiles from the feet of the kitchen this won't help either as any stress or flexing from under the units could still upset the whole floor, 14m of cracks is alot of movement, something is moving.

 

[KateME13]

Hi all--

First of all--thanks so much to everyone who has contributed to this thread--we really appreciate the advice which has been given. I have been back through the posts, and would like to sum up the advice as to where we go from here. I have highlighted areas where I'm note sure of myself--grateful for any comments--this is what we'll go back to the builder with.

1. The whole floor will need to come up, down to the chipboard.
2. On top of the chipboard--should we lay backer board AND decoupler, or just decoupler? I understand that if we do use backer board, it needs gluing AND screwing to the joists. DavieA suggested doing away with backer board, and replacing with ply (what thickness?), then decoupler. If we did that, I presume the ply should also be glued and screwed. What's best?
3. On top of the decoupler--travertine tiles need 'back-buttering' with the right adhesive--keraflex was mentioned (again by DavieA--thanks very much), and definitely no dotting and dabbing to be used. Adhesive must be pale coloured or it will seep through and look as though the floor has measles.:smilewinkgrin:
4. Grout--any special tips here?
5. Clean and seal the tiles.
6. 2 weeks after the tiles have been laid, the UFH needs testing at 5 degree intervals up to maximum heat.
7. Cross fingers.:lol:

Thanks again for your help so far.

 

[Rich]

Hi Kate, a decoupling membrane and backer boards is belt and braces but not many people will pay for both as it will add a lot of money to the job. I really do not believe that it was a lack of a decoupling membrane that has caused the floor to fail, a combination of not gluing the cement boards down and the dot and dab adhesive is much more likely. If the chipboard was correctly screwed down so there was no deflection, then the cement boards fitted correctly and the tiles fixed with a solid bed of adhesive, I think that the floor would still be intact. This would be my advice, rip the floor up back to the chipboard and carry out each stage as above.

 

[KateME13]

Dear everyone who has contributed/been reading this thread--
I wanted to follow up all your advice etc. with an update: our builder has agreed to pull up the whole floor (including taking out the units), pay for new tiles, and contribute towards the cost of a tiler to redo the floor. He will then put the units back, at no cost to us. So we are really happy with this, and wanted to thank this forum for the advice and support which allowed us to take a constructive approach to dealing with this problem. Now--all we need is a good tiler who knows about water u.floor heating and travertine tiles! Thanks again, everyone.

 

[Del W]

Got your pm Kate.Will be in touch.

 

[Bathfix Bob]

I'm glad he did the right thing and hopefuly learnt by his very expensive mistake.

 

[Del W]

Looked at this floor tonight.A nice couple with a problem that can be sorted.They are so glad of the info/support provided on here. Well done TF.

 

[Ken Bruty]

Great to see a happy ending

 

[kilty55]

minted result