Tiles coming away from Adhesive, Timber Floor with UFH - TilersForums.com

[clipboard2008]

Hi

I have a clients floor I laid in December 2013 that has tiles coming away from the adhesive.

The job was 100m2 of White Polished Porcelain (600x600) to be laid on 18mm ply which was biscuit jointed all over on 300mm joists. Across a Kitchen, Utility, Study, WC, Hallway, Lounge and Dining Room. The floor was pretty sound only one area slightly concerned me (where there has been no issue at all) There is wet underfloor heating across the entire floor underneath the ply.

I laid ditra mat across all the floors, this was filled and then the floor was laid. We used BAL Rapid Set Flexible in the Hallway and a couple of other areas. The rest of the floor was laid in BAL Single Part Flexible. Grout was BAL Micromax 2.

In every doorway I put in an expansion joint in between each room and every room apart from 1 wall in the lounge had at least a 3mm joint between it and the tiles

In March time the customer contacted me to say they had a clicking noise coming from the tiles which they suspected I hadn't put enough adhesive under the tiles. I went over and found that the noise was coming from 6/7 tiles by the front door and upon inspection it looked like the floor had dropped 2-3mm by the front door as you could see my grouting had 'split' (pic 1 & 2) I assumed it to be an issue with the sub floor and the customer didn't want to remove all the tiles so we decided to leave it and see what happened.

Earlier this month the customer had called me again to say that more tiles across a couple of other rooms had also started 'clicking' so I went to see the customer this week and the same clicking is happening in different areas across the floors.

I don't know why this is happening? There is no grout cracking, no tiles are cracking.

The only thing that doesn't quite make sense is that in areas where I have grouted up to something it looks like the floor has dropped 2-3mm please see pics. In the WC which we fully tiled it the wall tiles have come away from the floor tiles by 3-4mm??

The customer did a lot of research in to the sub floor and was sure it was sound. For example in the study the joists were resting on a concrete base so there should be no movement but there is?

Sorry for the essay but there's no easy way to explain it

What do you think?

 

[White Room]

To be honest the only way to find if the joists has dropped for some reason is to lift a few tiles to see, the only thing I can think of is when the ufh was switched on it dried out the timber.

The house isn't new looking at some of the woodwork.

 

[Chalker]

Probably he weight of everything on the timber joists, or shrinkage.Not a tiling fault.

 

[One Day]

I had a very similar problem last year. Thought I was going mad too until I noticed the amount of movement - small kitchen splashback upstand had moved about 8mm from the worktop!
Also noticed massive cracks in door casings and on the stair strings.

The house wasn't a new build but had stood empty for 2yrs with no heating.
Nobody told me that! I'll try and dig up some pics later.

Your problem is definitely movement. Not a fault of your tiling.

 

[Stef]

The only thing i can see is that you said you filled the Ditra then tiled, did you fill one day & tile the next or was it done in one hit?
It's defo a joist or 2 that's dropped though.

 

[Turkish tiler]

Timber dried and shrinked

 

[Rookery]

Am I seeing the perimeter movement joints grouted?

 

[One Day]

Am I seeing the perimeter movement joints grouted?

Please don't lets start that thread again!

 

[One Day]

I spent two days lifting tiles and "proving" it wasn't me!
The last pic shows an area highlighted in orange where the joists were not touching the brickwork. I cut a hole in the floor and took a video using my phone. It showed the cardboard packers! Yes - cardboard.
Floor construction was 10mm Wedi bonded and screwed onto 22mm chipboard.
Just WAY too much movement after I had done my bit - not before.

 

[Spud]

how thick was your adhesive bed ?

 

[TJ Smiler]

If it was a problem caused by your tiling then surely your tiles and grout would be cracking as the floor moves?? The fact that they aint tells me that you aint suggests to me that you have done everything right.

 

[clipboard2008]

The only thing i can see is that you said you filled the Ditra then tiled, did you fill one day & tile the next or was it done in one hit?
It's defo a joist or 2 that's dropped though.

On the first day it was done in one hit but that was in the lounge where we're not having a problem, the rest was dried then laid

 

[clipboard2008]

Am I seeing the perimeter movement joints grouted?

1 wall was grouted in lounge at customers request
front door was grouted up to and also rear bi folds, rest of the floor had at least 3mm between tiles and wall

 

[Stef]

On the first day it was done in one hit but that was in the lounge where we're not having a problem, the rest was dried then laid

If you fill the Ditra let it dry then tile to it you are basically doing away with what the mats designed to do, de couple.
It should be done in one hit so the adhesive is locked into the mat & is able to move separate from the mat.

 

[John Benton]

Had exactly the same this week, went back to to a customers where the floor has dropped about 5mm and broken the silicon seal. You can physically see the floor dropped and 3 tiles cracked. Never had this before but is it low grade timber being used for joists? He is willing to pay me to repair which is a relief.