Another garage conversion in the Northwest
Hello all. I am in the process of planning my garage conversion. I haven’t used it as a garage for years, and since I finally got my crawl space finished, heating and plumbing systems fininished, it is time to tackle the garage conversion.
FYI, garage space is about 460 sq ft.
I have a couple of questions about how to accomplish this.
1) My garage does not have a stem wall around the perimeter. The garage walls are finished with insulation and drywall. When laying the floor insulation, do I just but it upto the drywall on the existing wall? Even with 5” of foam? See below.
2)I believe I will need to take the drywall off the walls and add furing strips to make the wall a 2×6 (currently 2×4) and insulate.
3) I plan on raising the garage floor to be equal with the house floor about 6 and 3/4” above. My thoughts were to put a vapor barrier down, add about 5” of foam board, then two 1/2” sheets of plywood in a floating floor configuration.
4) Given the space, I would like to run my HVAC ducts in that space. I was thinking two runs of wall duct (3.25” x 10.5”) from main trunk line in crawl space (furnace and duct system already designed for added load) would work. With 5” of foam board, and the duct space, this would leave only 1.75” of space under the duct for insulation. Is this sufficient?
5) How big of an issue is the duct contacting the uninsulated part of the foundation for a little bit? The delta between the crawl space ceiling and the garage floor means the ducts enter really tight to the floor.
6) The HVAC installers used 6” round to the crawl space wall (from the main trunk) then converted to 6” oval. Going to wall duct should flow more for the long run to then end of the garage, but is it overkill?
Thanks for any and all help. I have read most of the guides, but I think this situation is a little unique.
I have a bunch of pictures for your viewing pleasure.
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