Ditra for Percelein Tiles on Screed UFH foundations

[Mmark]

I asked my builder to install Ditra, he advised against it, said it wasn't needed and would be a waste of money. He said we will have no movement problems and Mapi flexible adhesive is being used with Porcelein tiles. He said we should only use it with stone or if there was worry of movement.

We have concrete foundations, that he said has no sign of cracking or movement. Ontop of that we have a lot of insulation. A steel grid rebar was placed across the room, which the UFH was attached too. and then 75mm of fibre screed was used.

Should I insist on the ditra, or are we good to go?

 

[tictic]

as long as the screed has cured and you have commisioned your wet ufh before tiling to mfr instructions..i.e.turning temp up daily then down daily,so you dont thermal shock the slab..

and if you have any movement joints in it follow on through up tiles,and put movement joints in any door thresholds,and around perimeter off room when tiling.

dont forget the primer first tho...at 75mm thick it will be a sand/cement screed not a gypsum based one..

so sweep, then primer if your using mapei then their primer G..