Wet UFH over existing concrete and limestone tiling

[farmerben]

Afternoon all!

First post and not a Tiler but am hoping for some advice to prevent problems in the future. I am a farmer by trade so could do with some help on advising our builder on how we wish our floor constructed.

We are renovating and extending a barn that has been converted previous to us and this means that the living room will have half new floor with celotex and screed and half old 4 inch thick conctrete floor. The wet UFH will go fine in the new part of the floor (with ditra and tile over)but the old concrete part will be the highest part of the whole ground floor so wish to keep levels as low as possible. How would we go about getting the UFH on this concrete whilst allowing for a floor that could take limestone tiles?

Builder has spoken about tin foil coated polystyrene which takes the UFH pipes but I am guessing this is not good for a solid tile base, also chipboard with pipes installed has been discussed but I gather this involves connections from board to board which id not too good either.

Help!!

Any advice appreciated as we wish for a tiled floor but this will have to be wood if a strong substructure is not possible for tiles.

Many thanks

Ben

[Ajax123]

Have a look at the max4therm ufh system.it can be laid very thin

[ms.tiles]

poly pipe do a wet system that just has 18mm (i think) insulation boards with runs for the pipes to run in and can be tiled straight on top of, dont know if this is an option for you with your floor levels but it might work.
this system runs off your boiler at a lower temp so not to costly.