What paint to use for interior vapor retarder
I’ve been searching for a good paint Sherman Williams is out of that paint completely and not currently making it. Also some of the other paints I’m seeing are being labeled as perms of only 1.0 after paint. So does anyone have any recommendation of paint brands preferably something that exists and easy easy to get my hands on or wil any old latex paint do just as well.
Thanks, Tom
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Can anyone recommend a paint at all? I need a class 3 because I will have 2 1/2” of exterior foam. So primer and then 2 coats of paint but I’m unsure of what paint is acceptable to use for this purpose. Appreciate any help this is the last piece to my puzzle
You should have a quick read of these two articles:
https://www.energyvanguard.com/blog/you-don-t-need-a-vapor-barrier-probably/
https://www.jlconline.com/how-to/exteriors/q-a-vapor-retarder-paints_o
The first one basically says regular ol' latex paint and primer is going to get you to where you need to be. The second lists some specific paints.
Bill
Thank you
Don't trust a random latex over wallboard to be less than the typical code required 10 perm maximum. Sometimes Class III is risky (page x) and the low end of Class III, say 1 to 4 perm range would be safer.
https://www.research-alliance.org/pages/perm.htm
https://rockytopmat.com/product/58FB10-N
I don’t know how to respond to this when drying to the inside you want class three which is above 10 perms. The “ smart” vapor retarders are both at 13 when drying to the inside so in the article you linked the knockdown texture with paint over drywall seems to be exactly correct unless I’m reading something wrong