Bathroom tiles lifted - Tile Advice

[Smiler5714]

Defo expansion gap needed but also with any underfloor heating you need a solid bed of adhesive. One reason for needing a solid bed is for thermal transfer of heat up from the mat and through into the tile. Air is a very poor conductor of heat and so if you have air trapped between trowel ridges you have a very uneconomical system. Secondly, if the air pockets are quite large you can also have a problem where the heated air expands and again, it could possibly cause lifting of the tiles, especially if they weren't very well bedded to start with.

When solid bedding it's always better to butter the back of the tile.

 

[al strachan]

ignore

 

[Etherglide]

The trowel marks look like !0mm at the most. I suspect not back buttered. Oh, and the heating was turned on too quick. Dismiss an expansion joint at the walls. Most of us, if were being honest, don't tile tight to the wall anyway.

 

[jobirdster]

The trowel marks look like !0mm at the most. I suspect not back buttered. Oh, and the heating was turned on too quick. Dismiss an expansion joint at the walls. Most of us, if were being honest, don't tile tight to the wall anyway.

It took us over 6weeks to have the electrics for the UFH connected. We were advised 2 weeks was enough but we didn't have a sparky on site for ages.

 

[J Sid]

It took us over 6weeks to have the electrics for the UFH connected. We were advised 2 weeks was enough but we didn't have a sparky on site for ages.

Its the turning on and how the heat is ramped up slowly over the next week which is very important after the tiles and adhesive has set.
Turning the ufh on and taking it high straight away could give thermal shock leading to floor failure, looking like your floor looks now

 

[jobirdster]

Its the turning on and how the heat is ramped up slowly over the next week which is very important after the tiles and adhesive has set.
Turning the ufh on and taking it high straight away could give thermal shock leading to floor failure, looking like your floor looks now

Thank you to all who commented, we had someone independent to come out to assess on Friday and he has concluded that its the prep. Specifically no primer being used, which the tiler has admitted to only using the small bottle of primer that came with the UFH kit.

So now to get it corrected !

 

[J Sid]

From the pic's you posted I can't see it as a primer issue.
The adhesive has stuck to the floor and not stuck to the tile at all. Bad fixing method/no explanation.
Hope you get it sorted and maybe worth asking the next Tiler for commissioning process for ufh

 

[Anthony]

From those pictures posted it’s definitely the ufh getting to hot to quick! When tiles are insufficiently stuck they won’t crack and lift like that they’ll de bond and sit on the surface grout will crack giving that away. When stuck properly the adhesive will shrink and hold under tension (factor in curing time) then when heat is applied to quickly the properties of the adhesive can’t keep up causing lift and cracking. And debonding as tension is lost to quick. Certainly nothing to do with primer !

 

[eddcottee]

Where was this independent person from? I cant understand how primer is the issue, as the adhesive seems to have taken quite nicely to the floor. Albeit the adhesive has been poorly laid. If the issue was primer, the adhesive wouldn't have stuck to the substrate surely?