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What is the R-value?

agurkas | Posted in Green Products and Materials on

I found an insulation recycler that has 1.5″ polyiso for the price within my budget.
What I am trying to figure out, since Googling it does not produce results, what R value should I expect out of NRG Barriers 1.5″ polyiso?

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  1. GBA Editor
    Martin Holladay | | #1

    Polyiso has a nominal R-value of about R-6 per inch, which means that 1.5 inch polyiso has an R-value of about R-9.

    Keep in mind, however, that the performance of polyiso is degraded by cold temperatures. For more information on this issue, see In Cold Climates, R-5 Foam Beats R-6.

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