Favorite drain wrap?
RobInNorCal
| Posted in Green Building Techniques on
I searched on both WRB and Drain wrap/drainwrap and the most recent product roundup I found was from 2010. Comparing Tyvek Drainwrap to the many alternatives, do any of them stand out as the housewrap layer behind a rain screen gap? Is there any real value to using a drain wrap if the housewrap is covered by 3/4″ furring strips? Appreciate the insights and opinions, as always.
Thanks,
Rob
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Replies
Rob,
I can't see any advantage to using a drain-wrap behind a rain-screen cavity.
I use commercial Tyvek as a WRB. It is a lot stronger than the regular Tyvek, making it easier to use.
Both liquid WRBs and peel & stick ones get a lot of mentions here on GBA. I haven't tried either.
Drainwraps have enough of a "crinkled" surface to promote a surprising amount of bulk water drainage. But that benefit is of course rendered moot with the ventilated rainscreen of furring strips.
Peter
With vertical siding, the furring strips are horizontal - so one needs to either keep them off the wrb or find a way to get any water that enters the rainscreen cavity down the wall and out. I plan to cut 1/4" deep drain channels @ 4' OC into the back of the horizontal furring strips, but the idea of using crinkle-wrap too seems like an idea worth considering. [I looked at various ways to stand the furring strips off the studs but most of the gap goes away when the siding is screwed down.]