Insulation sheeting around a window
I am replacing a window on a 12 foot long single story wall on my house. I am debating installing 1/2 inch insulation sheets on top of my osb. I am in climate zone 4.
Anyway, somewhere on here I downloaded from the department of energy an information packet on the subject. Under "wall 1" example it showed putting housewrap or tar paper (#15) on top of the osb. Installing window rough opening flashing, then installing the window on top of the osb/tar paper. This serves as the drainage plane.
Insulation sheeting goes on top of this and on top of the window nailing flange I assume. I have a few questions though,
1. If the tar paper is the drainage plane, should the insulation sheeting seams be taped? (And what kind of tape should I use on the tar paper seams?
2. Most vinyl windows used with vinyl siding like I will be using have a built in channel to hide the siding. When I held a piece of insulation sheeting up to the window yesterday, it looks as if the sheets completely fill the channel making it difficult to put the vinyl siding in the channel. The only way I see around this is to somehow sand the thickness of the insulation sheet down so that the ends that go into the channel are a smaller diameter, or to cut away the insulation entirely so that the window nailing flange is exposed. (I assume the vinyl siding will "bend down" some enabeling it to go into the channel) I am not sure if this option will create a water problem or not if the window is flashed correctly.
The only other option I see is purchasing additional vinyl j channel and install it around the window. This seems the best option but my siding has been on the house since 1998 and there is no way to find anything that matches. (And I live in a rural area, my options are limited and I need to get this done this weekend.
So, what do you guys and gals recommend?
Posted Thu, 05/29/2014 - 07:45
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