Since we originally planned to install 2" of foam board over the exterior sheathing with house wrap over that. Our architect specified outie windows mounted on a plywood box extension (2" out from wall).
Now that the Roxul Comfortboard IS is available we would like to use that instead of foam, but it can't be taped and sealed like foam (making window sealing problematic at that layer) and since the compressive strength is less I imagine the window flanges should not be attached through it anyway.
Should we just put foam around the windows for ease of installation and just bend the house wrap to the outside of the foam at that point? I understand it is recommended to put the house wrap under the Roxul. Does anyone have any recommended window details for this kind of situation?
I read the details on GBA about installing windows over exterior foam. The Gienow vinyl windows have been ordered and the rough window openings are there, but not the window boxes yet. You can follow our progress here http://agreenhearth.com/?p=327