I was a heavy commercial construction inspector for 20 years... You say there's no basement, but from the looks of your exterior picture, is there's still a crawl space under the room? If so, it's no different than a basement since you still have floor joists to be concerned with. If it is a crawl space, is it dirt foor or concrete?
EDIT: just saw the rest of the posts.... how much hangs over the basement? If it's centered over the basement wall, there's a good possibility that nothing would need done.