Seeing the other question got me to thinking about the shed I plan to build this summer.
My land is shale with 0-10 inches of dirt on top. I don't know, but it seems to me that shale isn't going to go anywhere, so a minimal foundation will be adequate, perhaps even less than the 4" of gravel and 4" of concrete the other guy was talking about?
My county has a policy; if you leave them alone, they leave you alone. I don't know what code requires, and I bet the building inspector doesn't either. In a neighboring county I went through a new house that had significantly less insulation than the state requirement. I called the building inspector, he looked it up and said it was news to him. I mean, geez, insulation is about as basic as it gets.