On 26 Jan, 18:29, Tim S wrote:
Hi Andrew,

Last Nov 2008, you mentioned a system of UFH done with 10mm copper under the
floorboards.

The relevant BS, BS EN 1264-31998, recommends a maximum floor
temperature of 9 degC above the room temperature, i.e., 29 degC, 33
degC in bathrooms. You could work it out from that.

No-one uses copper for underfloor. PEX is preferable. The Rehau or
Uponor crimp fittings are much preferable to push-fit.

There has been some criticism of 'staple-up' used without radiant
plates in the US trade press; the design heat emissions often aren't
achieved. .