[GSBN] blowin heat below the slab

[contact at lamaisonenpaille.com]

Pascal Thepaut, a french SB builder of the first hour just called me to 
share some details on system that uses the heat from the roof to heat 
the slab. Pascal used this in his own recently build SB home and is 
happy with the result. He put in probes to mesure what goes on and in 
about half a year he should be able to read the data over the timelap 
that is necesary for the system to be fully operational. He expects the 
floor temperature to stabalize arround 16°C as this is what has been the 
result of previous projects where this system has been used. Pascal's 
house is in Brittany. This is west point of France that sticks out in 
the ocean, it has a mild and somewhat rainy climate. As they jokingly 
say over there: "In Britanny they have nice weather several times a day".

Here is a description of Pascal's setup:
The vented airspace below the roof alows the hot air to come into a box 
at the top. From there, when the temperature attains 22°C 2 fans blow 
the air in the 2 loops at about 90cm deep.
Soil was escavated to 1m
10 cm sand
PVC pipes (2 loops)
Base walls of insulative clay bricks + cork insulation on the inside
Rubble and earth infil, compacted in layers of 10 cm. A total of about 70m3
Lime-crete (reinforced with bamboo)
tiles (white)

If I get more data I will gladly pass it on.

André - may recyled heat warm our hearts - de Bouter

PS. Thanks Martin Oehlmann for getting Pascal to call me.