if the adhesive has parted company with the screed and not the tile then it was never properly bonded in the first place. This could be caused by many things or a combination of those things so you need to work systematically. Firstly you need to establish if the floor was a concrete floor or a screeded floor. It cannot be both... then you need to establish what type of concrete or screed it was, then the fun begins...
1. Was the screed tested and confirmed dry using an accurate and appropriate test
2. Was the screed mechanically abraded in line with standard industry guidelines (e.g. CFA and TTA)
3. Cleanliness - Was the screed clean, free from dust and contamination likely to cause a failure of adhesion
4. Was the underfloor heating commissioned correctly and fully
5. Was the screed properly primed using an appropriate primer.
6. Was the adhesive correct and appropriately applied
7. Was the adhesive allowed to properly set before stressing the tiles e.g. trafficking
8. Was the underfloor heating recomissioned correctly and properly after tiling was complete.
Any one or a combination of any of these could lead to this type of issue.
Thank you very much for the detailed reply.
I can confirm the following:
1. The solum was backfilled and compressed before being certified for the concrete.
2. The screed was supplied by a recognised supplier and certified and the dealt with it's application which included giving the screed a sand as they knew the finished flooring was tiles. This is marked on their invoice.
3. The tiler supplied all materials excluding the tiles and the job looked perfect hence why we paid the tiler.
4. The heating was left off for three weeks and was then slowly applied.
5. A number of months later the grout started breaking and we called the original tiler whom basically avoided coming back.
6. Two other tilers were recommended and a number of the tiles were tapped and you heard they were bose and once one or two were lifted the rest lifted using your fingers only.
7. It was noted in areas that the adhesive was 15mm and the tiler said that was not correct.
8. It was then and only then discovered there was no detra matting laid.
9. Upon speaking to the initial tiler he said the detra was not a requirement albeit we were led to believe the matting was down. He then said the problem was the heating being applied too quickly which once disproved he changed his position to saying a water leak had caused it as he noticed water on top of the tiles when he came back to finish another job.
We have spoken to the screed company and they said this is a common problem if the tiler does not make sure to test before applying any tiles as the screed can appear dry on top but still damp below.
