Getting a better insulated floor at rim?

[Montana Carpenter]

I am considering framing my basement walkout and daylight walls up to floor framing height, hanging my floor system within the walls with top mount hangers then sheathing over the top w/ 3/4 OSB. Has anyone ever seen this done? Would it pass UBC?
The reason for this is to give me a full 7'' of insulation at the rim (for lack of a rim)
Believe it or not there aren't much for building codes out here when one is outside of the city limits other than plumbing, elec and septic.

Thanks for your advice

[Rich]

It's done quite. Most recently seen it quite a lot with ICF foundations. Most ICF mfg's have a brickledge block that the floor joists can sit on.
And Montana has adopted the 2006 IRC, IBC.
If you really want an insulated rim your best bet is to run insulation at the outside of the rim (this includes your foundation as well). Recently we've been traditionally pouring our foundations and then running R-12 poly iso up the outside and extending it right over the rim joist. We then use a piece of metal flashing to provide a drip edge over the insulation. Then on the inside we spray foam the rim board again with the Dow HandiPack.