Leakage around windows and doors under housewrap
I am using osb sheathing as my primary air barrier and have caulked all panel edges before install along with taping seams with 8067 all weather flashing tape. Around the window and door openings I am also taping the osb to the framing. Tyvek will be installed and wrapped into window openings using the “inverted wineglass” technique. It seems, however, that unless I seal the tyvek to the rough opening framing, that air can leak through on the back side of the tyvek, even when the flanged window is installed, flashed, and caulked correctly. Should I tape or caulk the tyvek to the rough opening? Any other suggestions on making this critical area air tight?
Thanks,
Brett
Moses Lake, WA
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Replies
Brett,
Technically, you are correct about the potential for air leakage (although the amount of air leakage through that route would likely be minor). It certainly won't hurt to tape the Tyvek to the rough opening.
Some builders cut back the Tyvek in the rough opening so that the rough framing is mostly exposed, with the Tyvek folded in for only about an inch or so. That allows a better surface for your air sealing measures -- because, as I'm sure you know, you need a way to seal the crack between the window frame and the window rough opening.