In article , Ian
Stirling wrote:
If going from 0.25 to 0.1 costs around 1500 quid extra (and
incidentally knocks 50 cubic meters off the habitable space)
^^^^^^^^^^^^

Given that more than a few buildings are constrained by having to be x
from the boundary or some other limitation, increasing the wall
insulation thickness reduces the internal floor area. This is more
than just 'incidental' IMO.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
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