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Old 08-05-14, 07:28 PM   #3
AC_Hacker
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Quote:
Originally Posted by Mikesolar View Post
That foil is R 3.5 for over 2" thick. Not too good from where I sit.
OK, my bad my link to the conversion tool was incorrect...

Here is the correct link.

I use this conversion too so often that I have downloaded the SWF file to my computer, and book-marked it (local) in my browser.

So, here is how the conversion sequence goes:

R3.5, when reciprocated is 0.2857142857142857 (The U-value in SI inits)

When you look this up in the calculator, using SI units, you will see that the R-value, in units we are accustomed to, is not R3.5 but is actually R19.8.

My apologies for the bad link, but the correct values are absolutely worth paying attention to (and the real reason I posted the entry).

-AC
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Last edited by AC_Hacker; 08-05-14 at 07:31 PM..
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