WRB choice: Pro Clima Solitex Mento 1000 vs. Fortifiber Weathersmart drainable
I am in Portland, OR. and we have a 1927 built house that we are re-siding with 1/2″ beveled cedar boards. The house has a combination of new plywood and old ship lap on the exterior. We have a combination of R13/R15 fiberglass batts, net & fill fiberglass with 1″ XPS foam (cut and cobbled with spay foam on ship lap areas. I tried to make my air barrier the drywall but was only able to seal the top plates with acoustical sealant and some EPDM gaskets and caulk on the drywall to floor intersection.
It sounds like it was not the best choice to put XPS in the wall, but my goal is to have the wall able to dry to the exterior. I have vapor barrier primed and regular latex paint on walls now.
So, trying to decide on type of WRB to use to get the best drying ability. I would like to do a rain screen but the cost is out of our budget. I have a bid for new siding using Fortifiber Weathersmart Drainable and I am also considering Pro Clima Soltex Mento 1000. It seems this type of WRB is best with a rain screen but I am told it can be done without. Does anyone have any experience using this type of Vapor open but Air closed type of house wrap ? That’s it best selling feature, but the second selling point I was told is that this WRB is not chemically treated to be water repellent it resists the tannins from the wood underlayment and siding which supposedly degrades the chemically treated plastic house wraps. Looking to all your feedback.
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You're right that Solitex Mento is vapor-permeable while also acting as an air barrier. But the same can be said about virtually every other housewrap on the market, including Weathersmart Drainable. They are all air barriers (as long as you pay attention to penetrations and sealing the seams), and they are almost all vapor-permeable.
If you are not going to include furring strips to create a rainscreen gap, I would vote in favor of a wrinkled wrap like Weathersmart Drainable. There are several other similar brands out there, including DuPont StuccoWrap, Pactiv GreenGuard RainDrop, Barricade Drainage Wrap, Barricade WeatherTrek, Valeron Vortec, Fortifiber Hydro Tex, and Benjamin Obdyke HydroGap.
For more on this topic, see All About Rainscreens.