Since I had to dig down to put in footings and a foundation across the old garage door's opening (there was neither), the new foundation blockwork that I built is actually what created the bottom of the U shaped wall opening to begin with. I had built the block wall up to approximately 18" above the garage floor level, so that there would be some foundation showing under the bottom of the finished siding, which I kept 8" above grade to match the rest of the house. Having the 18" high block wall also creates a very wide and somewhat deep window sill aspect inside the house (once the interior framing of the room is finished), which my wife really wanted.
I framed the wall to hold the actual window flush with the exterior of the blockwork, using pressure-treated materials (with foam sill sealers) against the block itself, and non-pt materials around the window. Once I sheathed the exterior with 3/4" plywood and installed the window, everything was flush with the remaining wall and ready for siding (which I finished installing yesterday). I still need to do some finish trim at the top of the wall (on the roof eave and fascia).
Everything worked out very easily, and it looks very nice (if I do say so myself). Thanks to everyone for the input and opinions. It's good to know that my thoughts on how this was to be done were right all along.
Last edited by designerdale; 06-18-2012 at 09:02 AM.
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