Trying to finalize my foundation plan. Been referencing the 2018 residential code:
IRC 2018
I tweaked my footer more in-line with what the code states for a 1 story home in my soil conditions. I had a 24" x 12" footer, it is now 18" x 8".
I am wondering about wall thickness transitions. I have 9ft walls in the basement, code seems to dictate those should be 10" thick. For the porch and the garage I have the walls 8" thick. I don't care so much about the porch because it is covered with a concrete cap. However, for the garage the top of the garage slab sits below the elevation of the garage foundation walls 2", so the thicker those walls are, the more of a step of concrete I have around the inside perimeter of the garge floor. 8" wall, 2X6 sill plus 5/8" drywall = 1-7/8" step. If I can go down to 6" thick walls for the garage and porch there would be no noticeable step around the perimeter. I am referencing some architectural drawings of my brothers house and all the walls are 10" thick. So he has a 3-1/8" step around the perimeter and his garage foundation walls are 8" above his garage slab.
Wondering if it is a pain in the ass ($$$) for concrete contractors to have varying wall thicknesses and I should just have them all at 10" thick?
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