Another thought, you may need to check with the builder of the house to see what strength concrete he used in the part you want to use as a garage. I always had 4,000 mix with wire or rebar and fiber both in the garage concrete. Also the place you want to locate a new weight bearing wall may require a new footing under the slab.
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Yes, the S.E. will call-out the headers, beams, hangers, footings, post bases, post caps, etc. for you, all you need to do is the physical labor---Lol. Scroll down the choices (cursor over the letters) just on top-hangers here: http://www.strongtie.com/products/ca...lange_cwp.html
Let us know the outcome....
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