Can this even be done? 24x40, Half of our basement is going to be a finished walkout. (The other half is garage)
I had been planning on doing a slab in both halves because that's how basements are done. But it's occurred to me of late that I might be able to do a wood floor of some sort. Kind of like a REALLY short deck, at the height of just-above the footers.
I'd still do gravel and a vapor barrier beneath, I just would do a wood floor instead of a slab over top...
I think my biggest concern would be termites.
Yes you can. The permanent wood foundation folks have details. My pdf is from southernpine.com and is a 2.07mb download titled "Permanent Wood Foundations".
Here it is, bottom right of this page;
http://southernpine.com/publications.asp
Do remember that part of the job that a slab does is keeping the outside soil pressure from pushing the foundation walls in. The floor needs to brace the walls.
We built for a gentleman near Lex, NE and asked about termites... "what's a termite?" was his response. Are they a problem where you are? The wood is treated and you can soil treat.
Yes, they're a problem, but not the extent of say, Texas...
Lex is about 100 miles north of us. They're have less of an issue than we do, but my folks, who live in north eastern Nebraska had a couple of their basement door jambs that had termites, so yeah, they're around...
Our local firebarn (a pole shed on a slab) had to have the bathroom re-finished because termites had destroyed the finished walls.
So far as soil pressure, that's why I'm picturing the floor sitting above the tops of the footers, so as to brace the bottoms of the walls.