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Worth the cost

Minionr | Posted in Energy Efficiency and Durability on

I’ve been stalking this forum for a few years in preparation for building zone 4.  View faces north wind over ocean. Is there value in trying for R 40 wall if I’m putting in nine 4 x 5 foot windows on that wall, even if they are good windows?  How can I calculate that?  Thanks.

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  1. Expert Member
    Michael Maines | | #1

    It would rarely make financial sense to build R-40 walls in CZ4 even if you don't have large windows and an ocean-facing north view, but there are other reasons you might go above code-minimum levels. The only way to know the answer is to model the design and look at various options. I use BEopt for that, a free download from the DOE.

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