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Re: GBlist: Hemp Insulation?
At 02:49 PM 6/13/97 -0000, you wrote:
>First question, can anyone convert the metric thermal conducivity? Is
>there a web site with this conversion. (I've found several sites with the
>typical conversion factors, but none with this one.)
W/m *K X 6.935 = BTU * in/(hr*ft^2*deg F.) ie. k - value, so one inch of
0.048 W/m^2 *K is worth 0.33 BTU * in/hr*ft^2*deg F = thermal conductivity
Inverting this, of course, converts to R-3 per inch. Acceptable.
but one inch of 0.13 W/m^2 *K is worth 0.9 BTU * in/hr*ft^2*deg F or
roughly R 1.1 per inch; could be a good subtitute for opaque single glass.
- my guess is that the 0.13 is actually conductance (not conductivity),
for a thick sample eg. 40 cm (15 in.)
- then the units should be W/m^2 *K and multiplying by 0.176 will yield
.023 BTU/(hr*ft^2*deg F. or R-44
- but it's only a guess
[conversions from ASHRAE Fun-da-mentals, Ch. 35]
Them little numbers and letters is elusive - best left to professionals, who
have little else to recommend them but dogged determination.
See below.
>Second. What's the general impression of this product?
WOW! Far flipped away!
What R they smokin' in that test lab?
Mark E. Kelley III, PE
Building Science Engineering
85 Depot Rd. Harvard MA 01451
508 456 6950
dragon@world.std.com
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