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Basement Insulation: Ideal perm rating?

ARF9VudJeZ | Posted in Energy Efficiency and Durability on

Hello GBA,

What is the ideal perm rating for insulation being installed on basement walls in Zone 5? Is there a strong preference toward either XPS, EPS, or a closed cell spray foam? Lets assume that all basement moisture issues are taken care of.

I believe that controlling the air movement is the most important component of a dry basement assembly, but I also do have concerns about vapor diffusion and condensation at the block.

So many opinions going around out there….



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  1. jklingel | | #1

    "Lets assume that all basement moisture issues are taken care of." Not being a pro, I would wonder if that is a valid assumption. What does say?

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