Underfloor heating issue

TamsinC

Me again - hi! In the house we are buying there isa section of underfloor heating that has tiles laid on it - apparently the builder used the 'wrong' grout and the tiles kept cracking (I believe there should have been another layer between the tiles and the UFH) - apparently taking up the tiles and fixing this is difficult and the owner has overlaid the tiles with a laminate. How easy/difficult is it really to take up the tiles and fix the problem? (and possibly cost) Many thanks.

Warwick_Hunt

Is the underfloor heating electric or part of the heating system?

If it!!!8217;s electric factor in half a day!!!8217;s labour to remove it and the cost of starting from scratch. New heating mat and tiles.

TamsinC

It is wet and part of the heating system - the wrong grout referred to is the tile cement between tile and floor screed which should have been one suitable for use on floors with UFH. The concrete screed below this is a normal mix. Below that is the heating system laid in a polystyrene '' egg crate'', into which the heating pipes are woven, then an insulation layer and then the main reinforced concrete floor slab on damp proof membrane.

MikeEngTech

the floor is probably too hot. Floor surface shouldn!!!8217;t be more than 29 degrees in the middle of the room.

theonlywayisup

It is difficult to say how easy /difficult it would be to lift your tiles, but, I have UFH (wet) throughout our limestone tiled home. We had broken tiles when a fridge freezer was delivered and they were successfully lifted and new ones laid without destroying the screed or UFH.

If the tiles are cracking due to heat then it would seem the tiler/UFH installer didn't use a mat such as Ditra between the screed and the tile. Having been on the end of someone else's UFH barn conversion I can categorically say you need Ditra or a similar matting down before the tile is laid.

If you are happy you can lift the tiles without affecting the screed (which it sounds like they've been laid directly onto) then do it. Then lay a Ditra mat and use flexible adhesive to relay your tiles along with a flexible grout. I am no expert, but this is based solely on hard experience of the wrong way and the right way!