Over in the Basemwnt thread, several posters posit that a basement is required if the local ground freezes.
I was taught to alwas excavate the FOUNDATION FOOTER to well below the frost line, pour the footer, build the foundation wall (pour or block), then park either the house (raised foundation - house platform built on top of the foundation walls), or pour a slab resting on, and tied into, the walls. Anyone with class would excavate the area inside the walls and pour a slab on the bottom of the hole, thereby creating a basement.
In any event, whenever building on ground subjuct to freezing, a (8"x16" iirc) foundation was POURED below frost line, and the house somehow rested, ultimately, on that foundation.
Warm/hot climates, foundations MIGHT be optional…
Anybody know of simple on-grade (no foundation under perimeter) slab used in cold weather areas?