Air and vapour barriers
Interior sheathing as an air and vapor barrier
...OSB as an air barrier is that it is solid. A polyethylene or foil air barrier can be easily pierced by the slightest touch with a sharp tool, without even realizing it. In contrast, it is unlikely you will put a hole in an OSB air barrier that was not intentional, or at least unnoticed.
Blower door tests to measure air...
