Not that easy unfortunately: you need to do R/upper and R/lower
calculations. Example on our website at
http://www.sda.co.uk/shuvalpr.htm
No idea what uppers and lowers we are talking about - for doing a whole
room ??
But, it leads me to part L appendix B which has a nice example of studs
/ insulation /
sheathing that I can apply. The sums aren't to bad really, so no need
to buy superheat !
Thanks,
Simon.