Closed-cell spray foam and fiberglass combination system in exterior wall
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I am building a new home in zone 6 and am considering using 1″ of spray foam insulation on the inside of the wall sheathing, and then filling the remaining area with 6″ fiberglass. Wall framing is 2″x6″.
I am looking for some feedback on using this method. I would appreciate your thoughts.
Thank you.
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Replies
Rocco,
In Climate Zone 6, I wouldn't use less than 1.5 inch of closed-cell foam for this type of flash-and-batt installation, and 2 inches would be better.
Here is an article on the topic:
https://www.greenbuildingadvisor.com/fine-homebuilding/why-flash-and-batt-makes-sense
Thank You!