Extending R-value for cathedral ceiling
bowgus wrote:
... R20 conductance is .050 ... 95% efficient, and R28 conductance
is .036 ... 96.4% efficient or not much of a difference.
But a 2000 ft^2 R20 roof in a 10,000 DD climate will leak
24 million Btu/year, vs 17 million at R28.
Nick
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