It also depends on how the wall was designed. If it is a cantilever wall you may be correct. However, if it is a restrained wall and utilizes the slab above for support, I wouldn't recommend backfilling until the upper slab is in place and has reqached specified strength.
While I've never heard of a building department allowing or advising a concrete s.o.g. to bear the weight of the walls without a thickened edge or continuous footing, it doesn't really surprise me either. It seems that you could trench around the perimeter taking care not to damage any vapor...
Another option which would could still provide a slab without owering the load bearing is to create a waffle slab with 4" thick foam. You'd be surprised at the capacity you will get from 4" thick slabs with two-way action spanning to 8" thick ribs. Take advantage of the...
