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2″ Zip R-sheathing 45-degree mitered corners – GreenBuildingAdvisor
olanjide | Posted in Green Building Techniques on
My details for 2″ zip r-sheathing shows foam being notched out of one panel to the receive the other like in the attached image. However, the contractor decided to proceed with a 45-degree mitered corner. The house is in zone 5 with 2×4 existing stud wall, and 3/4″ board sheathing. It will be sprayed with closed-cell spray foam. How concerned should I be about the 45 degree corner and what seems to be an inherently weaker thermal joint? The corners are off course being taped. Does anyone have experience with this detail?
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Replies
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GBA Editor RANDY WILLIAMS | | #1
Your contractor went through extra work mitering the Zip-R. This method will work fine if the corners are tight, if not, canned foam might need to be added if there are voids between the two miters. Huber doesn’t specify how the corners lap, just that they do lap and are taped.
https://www.huberwood.com/uploads/documents/technical/ZIP-System-R-sheathing-Installation-Manual.pdf
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paulmagnuscalabro | | #2
As long as the corners get taped, I wouldn’t worry about it.
I’m sure it’s possible to come up with a measurable performance difference, but I would be pretty surprised if it amounted to more than an ounce of comfort or a few cents of efficiency in a year.
