a 75mm screed has been laid over a subfloor containing insulation and underground heating-pipes.
some areas of the screed have been levelled using a floor levelling compound. the heting was then introduced to the premises and it was noted, in areas, that some shrinkage cracks appeared.
the floor was then covered using marble tiles. over time some of these tiles, around the perimeter of the premises showed signs of cracking patterns. upon tapping the surface of the tiles some hollow sounds were noted, suggesting that the amount of adhesive used was inadequate.
the cracks were monitored over time and the movement now appears to have ceased.
upon lifting some of the damaged tiles we noted that the patterns of cracks on the tiles were mirrored by cracking patterns in the screed.
these screed cracks are between 1mm and 3mm wide and do not appear to have travelled through the depth of the screed.
i am wondering if it is safe to relay new tiles on the screed as it now appears or will we need to remove some undamaged tiles and follow the cracking patterns in the screed.
the pipes have been tested for leaks and they are all intact.