My attic was recently insulated with spray foam insulation, and now it is an unvented attic. Are there any concerns regarding this type of system? Do the benefits outweigh any potential risks? What are the pitfalls? Will there be any issues with moisture accumulation? Is there a risk of excessive heat build up in the summers?What about off gassing?
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Where is the insulation installed? Is it on the underside of the roof or on the topside of the ceiling? And, where do you live? Are you in a heating or cooling climate?
attic spray foam insulation
The insulation was sprayed on the celing, walls, and windows of the attic. I live in climate zone 5 with hot summers and cold winters.
Do you have a damp foundation? A wood shingle roof? Absent these issues, odds are, you'll be fine.
spray foam insulation
The crawl space has a dirt foundation. A vapor barrier was placed and then the foam was sprayed. I do not have a shingle roof.
In your other thread, you mentioned that it's open cell foam. That changes my eariler comments. Open cell foam could be a problem in the attic as it might allow moisture vapor to reach the cold underside of the roof sheathing where the moisture can condense. I'd be considering an air barrier on the underside of the roof.
Edited to change "closed" to "open" in the third sentence.
I think you just contradicted yourself.
How did I contradict myself? I corrected myself when I found out the foam was open cell.
How does closed-cell foam allow moisture to reach the cold underside of the roof?
Thank you. Fixed that.
I hear oo many stories of open celled foam acting like a sponge to such up and store vapors as water and lead to rot. There are way too many variables in each house, climate, and lifestyle to be able to give a single right generic answer to this Q