Outtie window details
I believe my windows are an outtie type window. I had initially thought they were innie style but now think otherwise, which is why I have provided the accompanying link.
This link will take you to the window information.
My builder has installed a half inch osb picture frame around the window openings and sealed and nailed down the flanges to this to bring the half inch foam board into the same plane. However my wsb housewrap has already been installed over the osb and the housewrap will be brought up over these small window frames. The foam will be added over the wsb. I’ve read the article on outtie and innie window details and know there is no steadfast rule on other than the recommended locations for the housewrap according to window style. Is my builders method of installation alright and if so, what other details should be made? My only concern is that the housewrap will actually slope down half an inch all the way around the window frame and then the foam will be in top of that up to the half inch window frame. We are not taping the foam board. And we are in zone 4 which adequately allows for half inch foam sheathing over osb.
Thanks
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Replies
Aron,
Q. "Is my builder's method of installation alright and if so, what other details should be made?"
A. It's hard to know without more information.
In general, to properly flash a window opening, it's best to flash the rough opening, not the window. That means that the rough opening needs a sill pan (either site-built or purchased). The sill pan needs a back dam, or it needs to be sloped to the exterior, or both.
The sill pan needs to be watertight, and it needs to direct water to the exterior surface of the WRB.
You need to know what material you have designated to be your WRB. In your case, it would probably be the housewrap.
The jambs of your rough opening also need to be flashed. Your jamb flashing needs to meet your sill pan in a watertight manner, using either laps or peel-and-stick flashing.
At that point, your rough opening is flashed and ready for the window to be installed.
Once the window is installed, you need to be sure that the window has head flashing, and that your WRB laps over your head flashing.
You can view a series of videos on window flashing here on the GBA site. The first video in the series is called Window Sills That Won't Rot.