1/2″ splash of closed cell air and vapor barrier?
tupchurch
| Posted in Energy Efficiency and Durability on
Local builder I know in Memphis (zone 3) uses 1/2″ splash of closed cell insulation for air sealing plus fiberglass batts in a 2×4 wall. All the guidance I have found for ratios of splash and batt are zone 4 and up and I also can’t find a perm rating for less than 1″ of foam. I am trying to figure out if this is a problematic combo or not. Thoughts?
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Replies
1/2" of closed-cell foam would be somewhere around 2 perms, higher than the OSB they are probably using for sheathing.
It's called a flash coat, not a splash coat. Though I have seen some foam installations that were messy enough to be called a splash coat.