Hardwood Flooring Vapor Retarders
Hi all-given this crowd tends to be very knowledgeable about vapor retarders and such, I’d love to hear your thoughts on the NWFA (National Wood Flooring Association) requirements to put a vapor retarder between the subfloor and the hardwood floor. I understand if this was below grade, or sitting on top of a crawlspace. But for standard main floor install over a full basement that is conditioned where humidity is controlled, what is the point?
The two most common products on the market aside from 15lb felt (which I’m not sure I want to use-health reasons??-not even entirely sure) which I am aware of are Silicone Vapor Shield and Aquabar. Both have perm ratings of approximately 0.7 or thereabouts once nailed. That is pretty tight, and makes me nervous putting that type of retarder between two layers of wood.
I’d love to know your guys thoughts on this. I’m obviously concerned if I don’t follow the NWFA retarder guidelines, it possible my void the warranty of my floor. At the same time, I don’t want to cause any subfloor moisture issue (which shouldn’t occur I wouldn’t think, as humidity is controlled and I’m above a conditioned basement). Thoughts?
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