Large format popped around edges

[Gary Lee]

Hi guys I wonder if anybody can tell me what's gone wrong. We have laid a load of 1200sq porcelain tiles using the retailers recommend adhesive. The ufh was fired up a week later and temp was raised a couple of degrees per day and every tile has lifted around the edges. They are still stuck firm in the middle. We used the prolevel levelling system to help align the joints. It might be worth noting corex sheets were taped over the top fee a couple of weeks and locked a fair bit of moisture in. Before I approach our public liability company I'd like to know what's caused it. Thanks in advance.

 

[Time's Ran Out]

What was the substrate?
Any decoupling/crack mats used?
Adhesive type?
Adhesive bed depth?
Solid bed fixed or have the levelling clips pulled the edges up?

 

[Tile Shop]

how many square metres is "a load"?
how big are the grout joints?
Have you used expansion joints or left a perimeter joint?

 

[Tile Shop]

also, is the adhesive still stuck to the tiles, or the floor in the affected areas?

 

[Italy]

instead I want to know:
how big are the tiles and the thickness

 

[Gary Lee]

Hi thanks for the replies. They were laid over a flowing 40mm screed that had been down for two months as instructed by the company. No decoupling mats were used, the adhesive was norcros S1 standard set flexible Norcros Standard Set Flexible S1 Grey Tile Adhesive - Norcros Adhesives, trading division of Norcros Group (Holdings) - https://www.ribaproductselector.com/Product.aspx?ci=27063&pr=NorcrosAdhesives-NorcrosStandardSetFlexibleS1GreyTileAdhesive they were laid with a 10mm notched trowel and clips were used, there was a curve along the edges and most corners pulled when the clips were tightened. The room is 8mx8m and joints are 3mm and 10mm around the perimeter. I haven't lifted a tile yet as they are all still fixed in the centers. They are 1200mm X 1200mm x 12mm porcelain

 

[Waluigi]

‘A week later’

Too soon IMHO

 

[Tile Shop]

BS5385, part 3, C.2.4:
"Once the floor tiling is installed, the heating system should not be run for at least 10 days in order to allow the tile bedding to cur/dry thoroughly".

3 days too soon shouldn't make too much difference, but the cold temps we've had recently would drastically slow the curing process.

 

[Dumbo]

Did you back butter the tile , most on here would advocate using at least a 10mm trowel on the floor and a 6mm notch trowel on the tile with the ribs running in the same direction .

 

[Tile Shop]

Hi thanks for the replies. They were laid over a flowing 40mm screed that had been down for two months as instructed by the company. No decoupling mats were used, the adhesive was norcros S1 standard set flexible Norcros Standard Set Flexible S1 Grey Tile Adhesive - Norcros Adhesives, trading division of Norcros Group (Holdings) - https://www.ribaproductselector.com/Product.aspx?ci=27063&pr=NorcrosAdhesives-NorcrosStandardSetFlexibleS1GreyTileAdhesive they were laid with a 10mm notched trowel and clips were used, there was a curve along the edges and most corners pulled when the clips were tightened. The room is 8mx8m and joints are 3mm and 10mm around the perimeter. I haven't lifted a tile yet as they are all still fixed in the centers. They are 1200mm X 1200mm x 12mm porcelain

Laitence removed?
Primer used?

Still no mention of back buttering, so chances are you lifted the tile out of the adhesive. A 10mm serration on its own is insufficient on large format tiles.

 

[Time's Ran Out]

40mm poured screed!
Possibly a gypsum based screed with a standard set s1 adhesive!
Surprised if there is cover on a liability insurance for workmanship.

 

[Dumbo]

BS5385, part 3, C.2.4:
"Once the floor tiling is installed, the heating system should not be run for at least 10 days in order to allow the tile bedding to cur/dry thoroughly".

3 days too soon shouldn't make too much difference, but the cold temps we've had recently would drastically slow the curing process.

Maybe covering with the corded may have slowed the curing time also . So possible accumulation of factors there .

 

[Gary Lee]

The radiators were on in the house and it was fairly warm. The ufh was only opened up very slightly we didn't notice any warmth for the first few days. The backs of the tile were not back buttered which I first thought could be the problem although it wouldn't explain the edges only popping. I can't actually find a datasheet for the adhesive. It's not even listed on their website, I will email. The smaller cuts around the perimeter seem to have stuck well. Thanks for your help guys.

 

[Gary Lee]

Yeah the floor was pretty wet when we lifted the cordex. The tile shop recommended adhesive based on the floor screed spec and tiles they supplied. Could they have issued the wrong stuff. I have a feeling not buttering the back of the tile is possibly the problem here. Apparently my pl covers workmanship so my partner says but we'd rather not make a claim if possible. Willing to hold my hands up though. Laurence was fully removed and primer also recommended by the tile shop was used. I'll have to find out what it was .

 

[J Sid]

as TJ says, 40mm flow screed. Exactly what is this screed?