Hi Andrew,

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

Do you have any feeling for how hot the air gets in the inter-joist void,
under the pipes?

Your system would fit *very* well in my house, but I'm wondering how much to
derate the electrical cables by.

I've got the margin to go to about 45C or possibly 50C ambient air temp
absolute max.

I don't imagine the air gets that hot - but as you're heating an entire room
through wood, I'm not certain of that.

Ta muchly in advance.

Tim