"Rick Dipper" wrote in message
...

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

......
Another problem that can arise with very high levels of insulation and a
well sealed house, is large amounts of condensation.
In Scandinavian new builds I've seen this has been specially catered for.