Does an interior air barrier attached to the inside of Zip sheathing form a continuous air barrier?
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I’m renovating a townhouse, meaning I have a front and back exterior wall but my side walls are shared with my neighbors. Obviously I cannot do the traditional thing and put Zip on all sides.
I was planning to put Zip on the front and back, and have a different type of airtight membrane on the interior walls. However, the question remains, how do I transition between these two?
The easiest answer is to tape the interior air barrier against the back of the Zip sheathing. However, I don’t know whether this counts as a continuous air barrier — is the OSB itself airtight, or just the green layer on the front? If I tape the interior air barrier to the inside of the OSB, is air going to pass through the side of the OSB into the house?
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