J
Just Rizzle
laying any tiles on a un protected screed with under floor heating leaves you vunerable if the screed begins to crack under expansion and contraction even if using anhidro addy. think you have been lucky so far. if the floor cracks so do the tiles. been and seen so many insurance jobs were tiles have cracked on new screeds due to ignorance where the tilers have chanced it. makes me my money though love it. been using decoupling membrain for 10 yrs plus mainly ditra but have started using the bal membrain on certain screeds