Andy Champ wrote:
The Natural Philosopher wrote:
Tim: the heatloss down to heat loss up ratio is entirely dependent on
the ratio of insulation underneath to isnualation above `(flooring,
carpets dogs/cats sofas etc)

Seems improbable.

If the floor's at 25, and the room at 20, but the ground underneath at 5
I'd expect a *lot* more loss downwards that if the ground underneath
was at 15.

You run UFH at around 45C water.

At that temp the differential between heat lost down to up, is much less
dependent on outside temp: inside temp.


And I suspect the "U" value of several metres of dry soil could be quite
high - whereas wet soil, with water trickling through it, could steal
enormous amounts of heat.


3 meters of wet soil is about the same as 50mm of polystyrene.

Bur the thermal 'mass' is vast.

takes days of heating to get it up to temp..


Andy