Self Levelling lifting

[wayne huson]

Interesting!
I'm having various issues with the bostik cempolay deep. The first issue was an area began to lift and created a large bulge of about a square meter. it actually raised 34mm away from the existing screed it was laid on. I used a PVA and water mix as a primer and made sure the floor way clean and dust free before laying the slc. On inspection i removed the offending area and relayed new slc unable to ascertain a reason for it lifting. My customer was happy to leave the floor for a couple of weeks before he had his floor laid, so we could be sure the problem didn't reoccur.
Since having his floor laid and over a few months the problem is back and in different places and worse. It seems to be expanding! to the extreme where it has actually pushed in and cracked the walls it was laid up to. This expansion would explain the bulging and de-laminating! Has any one else had this problem and could it be due to expansion?

 

[vinn]

wayne huson,
its usually better if you open a separate thread?
FWIW: post photos and short paragraphs might get more responders?

 

[L95]

For starters PVA is not suitable for tiling applications. Use acrylic or SBR. If it's bitumen or anhydrite then you will be in up to your neck as it will probably fracture throughout.

If bitumen then remove about 90 percent of it.

And walls cracking? Did you leave a 10mm expansion joint and then silicone the movement joint? Or dis you but it up to the wall?