S
Stevoe
Hi everyone, I am in the middle building an extension, the outer shell is up and most of the windows are fitted. I have laid 75mm insulation on the concrete then 300 micron dpm then warm water ufh pipes (holding pressure nicely). I am now ready to flood the place with a self levelling liquid anhydrite screed to a depth of 65mm. The area totals 60 square meters and is four rooms, kitchen (former garage) work room (nearly a new garage) utility room and downstairs loo. The biggest room is 22 square meters and I will be fitting porcelain tiles throughout all 4 areas. My question is should I fit an uncoupling membrane (homelux, Ditri) over the screed before tiling or will flexible grout be enough, my understanding is that the screed expands and contracts at a different rate to the tiles but as it is a water system the movement won't be too much. The UFH manufacturer says the membrane is optional, Topps Tiles salesman says I must fit it and and an independent local tile merchant says flexible grout will be more than good enough. I don't want to spend £400+ on matting + grouts if it isn't needed. Any avice would be appreciated.