Will Water Re-Vaporize?
We are having a very difficult time figuring out a WRB for our home in Massachusetts. After reading a great deal about house wraps and learning that condensed vapor trapped behind Tyvek rotted sheathing, we became afraid to use anything but 30-lb asphalt felt, feeling that it was "smart" and "forgiving".
But as we were shopping for Siga tape we learned about Majvest house wrap. We were told that its high permeability would let out trapped water (condensed vapor) because the water would vaporize and escape. Is this so?
We are fixing up a tiny cottage on a very limited budget, trying to get the most energy efficient value for our money. The 1 x 4 wall assembly is to be fiberglass siding (with built-in rain plane), WRB, air-sealed plywood, dense-packed cellulose, air-tight drywall with 2 coats of latex paint (maybe vapor retardant paint because the building inspector demands a vapor retarder.)
This is a DIY project for everything except the cellulose and we are in our 60's so things move s-l-o-w-l-y and Majvest might hold up better waiting for the siding to be installed, but not if we are risking wet cellulose.
Regards, Deb Davis
Posted Oct 2, 2012 12:38 PM ET
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