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re: reflectix duct insulation
21 feb 2006
m ransley wrote:
>it is not r 6, it says it is " like r6" and it gives different r values
>for different aplications for the same product, id say it is bs.
that's because you are ignorant :-) different conditions give different
r-values, but they are predictable. for instance, table 2 on page 22.2 of
the 1993 ashrae hof says a horizontal foil with a 3.5" air gap and a 50 f
mean temp with a 30 f temp diff and emissivity e = 0.05 will have r2.01
for upward heatflow and r8.17 for downward heatflow (with no convection.)
the energy savings are quite real.
nick
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