HELP.........UNDERFLOOR HEATING ADVICE PLEASE

Hi Guys......a bit of a problem which I am sure can be overcome. The buyers of a farm house being renovated have decided, after the 100mm concrete floor has been laid, that they want underfloor heating.

Question is what would be the best system...(there is 100mm of celotex under the concrete floor). Any solution needs to be as thin as possible because of door heights etc, but also to have heat loss integrity. Any ideas would be gratefully received.

Any thoughts guys??

this is just one of a few manufacturers that make overlay ufh,

http://download.polypipe.com/oracstar/48039-Catalogue-67.pdf

you will have to do a bit of research as I dont think its used that much, I have used the polypipe once and it seems ok and adds 18mm to the floor.

Picasso.....that was really useful.....have looked at the site with intest........thanks