Problems with karndean

Can anyone help please?
We have had karndean fitted in our home by very experienced fitter in November 2014 over most of ground floor. It is an old house which had a lot of rising damp so builder dug up old floors and installed damp course and new floor with underfloor heating. The subfloor was poured over underfloor heating pipes and heating left on for 4-6 weeks before fitter was happy that moisture levels had come down to acceptable level. He came over every week to measure with a hand held device. He then painted a green coloured primer over subfloor and then latex before gluing karndean on. The job looked great until we noticed karndean lifting, initially under 4 doors between rooms. When tiles lifted, latex had stuck to tile but had lifted from the subfloor. There was a crack in the subfloor under 3 of the doors and installer thought this was cause of karndean lifting as there was no dampness. However, it has now lifted in two more places :the hall ( away from any door) and again latex stuck on karndean but has come off the floor. it is also lfiting at one edge but here the tile has lifted from the latex and the latex is stuck to the floor. He has checked moisture levels again with hand held device and they are just about ok. There is no visible dampness on tiles or subfloor and no damp smell. he says he will use another more sophisticated device now to measure the moisture which has to be left for two days to take a reading. We are all baffled....any suggestions welcome.
Thank you

 

Find out what screed the builder put over the underfloor heating pipes.

 

Was it a liquid cement? How deep was it poured?

 

Anhydrite sceed came ready mixed and applied from hose

 

did he grind it?

 

What screed/primer did he use over the Anhydrite as in make and manufacturer. Can only use certain screeds over Anhydrite.

 

I know but be interesting to found out what materials were used.

 

Not grinder used just painted a green primer on then latex but don't know what type.

 

Check with the builder what type of screed was pumped in. This is essential information.

If we don't know then we're just guessing. Most of us suspect what the problem is and the cause but we have to know what screed was pumped in. Otherwise we could give advice that is incorrect.

 

They said anhydrite trimmer

 

Anhydrate mr Trimmer or are you wanting specific manufacturers? A surface scanning moisture meter is useless on these

 

Needs to be grinded to remove the lattice which happens during drying
The lattice should also be removed to aid drying

 

P131 has been used unless anybody else knows of another green primer, id also bet top dollar that he has used a cement based screed too, could be/probably the case that the fitter didn't realise what he was up against!

 

Oops. Just reread thread.

P131 is a common green primer. Not compatible with anhydrite though.

 

Sorry to say it sounds like the latince hasn't been removed.
Anhydrire is fairly new to the domestic building trade and unfortunately some tilers and flooring men are being caught out with this.
Some are saying it upto the builder to remove the latince, either way the flooring contractor should have checked before fitting.

 

Time to get the whole lot dug up and start from scratch...
Wonder who is going to fork out for this one

 

Anhydrite takes ages to dry out too!! It dries patchy and from the top down. I'm sure the heating would of helped dry it but from my experience it's a long wait untill fully dry

 

will fall up mostly, grind the top check its dry and try again