Housewrap WRB Left Exposed for Too Long… Add a Layer?
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Hello, I’m finishing up a tiny house in Zone 2A, near Austin. In late May, I wrapped the house with Tyvek Commercial Wrap (9-month UV exposure rating). In mid-July, I installed the windows/doors with Zip flashing and stretch tape (6-month rating).
It might be April before I can install the siding (w/1/2″ plywood rainscreen), and we had a long, sunny, dry, record-hot (103+ many days) summer. So I’m worried about these UV ratings. Can/should I just wrap another layer of Tyvek over everything? I don’t want to staple through the window flashing… so maybe there I could hold the Tyvek in place with a little piece of tape, then hurry to install the rainscreen?
Pretty rough/stressful realization that I just can’t make my deadline, but I don’t want to trade bad for worse…
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Replies
It can't really hurt. But, you could also just use it as temporary protection rather than carefully installing and detailing the second layer.
Well, if I put it up, I don't want to take it down again. I'd have to patch all the holes under it. The detailing of the 2nd layer couldn't be that intense anyway, unless I pull the windows out...
House wrap holds up for a long time, well past its official UV rating. If it is a matter of a couple of months I would not worry about it.