Ideal double stud wall?
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What do you think is the best way to go about buidling a double stud wall?
Is it better to use spray foam insulation a couple inches thick, followed up by cellulose and let the exterior sheathing dry out?
My idea for a cost effective way to do this is double 2X4 wall approximately 10 inches apart. 2 inches of closed cell foam on the inside to stop water / vapor. Fill the rest of the cavity with cellulose then drywall it. Outside sheathing will just be normal tyvek housewrap with vinyl siding.
Is there a better more cost effective way to achive a similiar (R40 ish) insulation value?
Denis
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Replies
Denis,
You are double posting. My answer to your question is the same as the last time you asked it. Skip the spray foam and fill your double-stud wall with dense-packed cellulose.