Shims and/or spray foam around vinyl windows
Windows were installed on our new build while I was out of town. These are Jeld-Wen vinyl casement windows, and the installation instructions say to shim at various locations on the sill and jambs. Well, this wasn’t done at all. I’m insisting that this still needs to be done, thinking that Jeld-Wen probably thinks that some support is required in these areas. Builder says it won’t matter because the window will be foamed all around and it’s not going anywhere. So I’m wondering if he has a good point (ignoring for now the warranty implications of not following manufacturer instructions), at least on the jambs.
On the sills, which are sloped, I understand that we’ll want to limit the foam to a bead along the interior edge of the window, so that the sill drains freely. But I’m wondering if you could go most of the way out to the exterior edge of the window with the foam in a few spots along the sill, in effect creating foam shims. Does cured spray foam have that kind of strength? Reason why I think this might be preferable is that the sloped sill and the bottom of the window are not in parallel planes, and I’m afraid that the shimming might not be careful enough to bring the top surface of the shims up to the plane of the bottom of the window.
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