I do the traditional joist thing using rough sawn hemlock on lofts.
The main floor is either concrete slab or processed stone.
I helped out on a drive under barn once where the main floor was framed 12 inches oc, then topped with a t&g 2x floor and a 4 inch concrete slab on top of that.
Last edited by RCBerry; 04/01/07 01:21 PM.