Zip-R sheathing in the Pacific Northwest

joenorm | Posted in General Questions on February 12, 2019 10:06am

I have read many concerns about Zip-R sheathing having the insulation on the “wrong” side of the sheathing.

Is this a concern in a more temperate 4c climate zone? I’m not sure of the cost of zip-R, but to get everything done at once seems pretty cool.

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MALCOLM TAYLOR | Feb 12, 2019 01:21pm | #1
Joe,

Was long as y0u provide a rain-screen cavity to allow the outside of the Zip-R to dry it will be fine. Depending on where in the PNW you are it may not meet seismic requirements for shear though.
Peter Yost | Feb 13, 2019 08:19am | #2
Hi Joe -

Ideally, yes, you want the structural sheathing warmed by the exterior insulation. BUT, I believe that the combined, continuous, and rigid water and air barrier the ZIP provides is well worth the ZIP overall configuration.

Matthew_M | Feb 13, 2019 03:15pm | #4
I'm not Peter, but I'm currently building my own house with Zip R-9. As far as I'm concerned, this is default sheathing I'll use for other houses I'll be building.
The R-9 version works nicely with 2x lumber ripped to block out around window openings, since the insulation is also 1.5".
The labor savings vs. continuous exterior foam board is considerable.