“Picture frame” method for outie windows
i am installing outie windows in a house with 4” of exterior rigid insulation. the windows are all triple pane in the following sizes: 24” x 24”; 30” x 30”; and 32” x 64”. the method that i would like to use to install the windows is mentioned in the article http://www.greenbuildingadvisor.com/articles/dept/musings/installing-windows-foam-sheathed-wall :
“Install a picture frame of 1×4 lumber, installed on the flat, on the exterior surface of the rigid foam. The 1×4 picture frame is screwed through the rigid foam to the sheathing and framing.”
i haven’t been able to find much else in the way of information on this method. the information i have found is either for a picture frame used in conjunction with a window buck or a picture frame installed directly over the sheathing with the insulation butting up to it.
i am planning on using structural screws from grk (https://www.grkfasteners.com/products/structural/rss ) that are long enough to penetrate the framing by 1.5”.
based on the relatively low weight of the windows and the use of structural screws, can this method be used without a window buck and installed overtop of 4” of foam? also, is there any detailed information available regarding this method that i could present to the building inspector to ensure that he will approve it and to the window supplier to ensure that it will meet their requirements for warranty purposes?
any information greatly appreciated. thanks!