On Fri, 20 Aug 2004 19:09:49 +0100, "IMM" wrote:


"Ian Stirling" wrote in message
...
Rick Dipper wrote:

I have worked out the U values of the insulation I intend to use in my
cavity walls, I have 2 solutions

1) Blocks -celotex-rockwall = 0.224 W/m2K
2) Blocks -2 * rockwall = 0.255 W/m2K

0.255 is poor. You should be aiming for 0.1ish


Sir IMM

Even at 2.55 the insulation is costing more than the
blocks/sand/cement. My outside wall has a lean on it, I intend to fill
the whole space with insulation, giving some 8 - 10 inches of the
stuff at the top of the wall. 8-10 inches of celotex is mind blowingly
expensive.

200mm Rockwall at 0.037 = 5.54
+ blocks .6666

Comes out at 0.16, getting down to 0.1 is gonna make for some very
expensive walls.

The idea of more insulation at the top of the walls feels good, heat
rises, so the tempertaure difference is bigger at the top. My room
will be 3 meters high of walls, with 2 more meters to the top of the
pointed roof.

Thanks
Rick