Housewrap over XPS or not?
I’ve read about wrb’s and foam and would appreciate any opinons regarding my situation. I’m enclosing my timber frame with a wrap and strap approach using reclaimed xps. Seams are all caulked and taped with siga wigluv 60. I’m debating how necessary house wrap is in this scenario. Other details that might be worth considering: 1″ straps and 1×8 plank siding with a 6″ reveal, 42″ deep overhangs on a roof with a rake edge elevation of 12′. The house is in the woods and location is western Adirondacks of New York. Thanks
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Daniel,
Building codes require every wall to include a water-resistive barrier (WRB). If you want to use rigid foam as a WRB, you can, but there are limitations and disadvantages to consider. Strictly speaking, I don't think that using recycled foam as a WRB would be code-compliant.
For more information on this issue, see Using Rigid Foam As a Water-Resistive Barrier.
My local codes has seen the installation of the foam and actually left it up me, having expressed approval with the xps as a wrb. I've read the article and have gone back and forth on a final decision.