More discussion on “Where does the housewrap go?”
Hi all,
We are getting ready to frame our “Pretty Good House” and I have a question about the housewrap. We are going with or 3″ of exterior rigid foam and “outie” windows. The house will be brick, (if that matters).
In reading the article about “Where does the Housewrap Go?”, I see that outie windows need housewrap at the level of the windows, which means the Housewrap needs to go outside of the foam insulation. I have communicated that to the builder and he is fine with that strategy.
However, my builder mentioned that he usually puts the walls up with the housewrap already attached (directly on the sheathing). He does this as a labor-saving technique. He also noted that wrapping outside the foam would be harder due to the thickness.
So, here is my question: Would it be OK to install the housewrap like he normally does (before the foam) and then put housewrap around the window, sealing that to the outside of the foam?
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Replies
Clay,
You can put the housewrap almost anywhere you want, as long as you follow basic principles. It's even possible to have two layers of housewrap: one between the sheathing and the foam, and another between the foam and the furring strips.
Here's the important principle, however: You need to know which layer is your water-resistive barrier (WRB), because all of your window flashing, door flashing, and penetration flashing has to be integrated with your WRB.
If you install housewrap between your sheathing and the rigid foam, that layer can be your WRB. Just make sure that your window flashings are integrated with that layer.
If you want to use rigid foam as your WRB, you can do that instead. Again, all of your window flashings would need to be integrated with the rigid foam layer.
Finally, if you want to install a layer of housewrap on the exterior side of your rigid foam, it is certainly acceptable to use that housewrap as your WRB -- as long as you have developed details that allow you to integrate your wall flashing with that layer.
Thanks for the reply, Martin. Sounds like there is no preference, as long as it is done right? It seemed like the preference in that article was that the housewrap needed to go outside the foam. Is there one that is best? One that is easiest/less labor-intensive?
Clay, I believe the standard method is to put your WRB between your foam and sheathing if you are using "innie" windows and between foam and furring if you are using "outie" windows. It makes flashing at openings easier since everything is on the same plane.