Does this appear to be “tar paper?”
1869farmhouse
| Posted in General Questions on
Found hiding under the EPS. Assuming it’s at least 60-70 years old. And if it is, it would be a vapor barrier correct?
Thank you all.
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Replies
Looks like tar paper to me, which is usually a kraft paper material with a black coating. If it’s thick and tough it might be asphaltic fiberboard.
I think both materials act as smart vapor RETARDERS, not full vapor BARRIERS. These materials aren’t like a sheet of polyethylene, for example.
Bill
Any possible way to determine perm rating on something this old? I sprayed closed cell on the interior knowing that the exterior was only 1/2” of eps... but only just realized this papaer was hiding under the eps.