John, Cumberland Mountain/The Cumberland Plateau is mostly a huge pile of sedimentary rock (sandstone and conglomerate). The footers are approximately 12 inches down and sitting, mostly, on ledge. We'd need to blast through rock to go any deeper there there, which may make a septic system ... challenging. Yes, the base at the corners and all along the tall wall are 12-inch block. Some rebar and the block is partially gravel filled and will have more rebar and concrete added when the slab gets poured.
Inside the foundation, it took about 50 yards of 67 gravel to fill. I'll run the plate tamper over it one more time and then we should be ready for the plumber and then the concrete.
