"IMM" wrote in message
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"Ian Stirling" wrote in message
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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

No he shouldn't ! The L regs require 0.35. Of course doing better than
this is a good thing but you are better off spending the money improving
other heat losses - windows and doors for example.