Back porch addition problems

Planning to build back porch on the rear of our brick house...lean-to type, 7' x 16'...want to run from post and beam to ledger on the house. Problem is, to match the back door floor I am only 7-11 inches above ground/sidewalk. I can sandwich 2/3 2xs for joists but even at that I am almost on the ground with the plate and ply etc.. I can use ground contact and standard treated but I still have zip for a 'crawl space' insulation and moisture control. Any suggestions on what to be concerned with and what not??
Thanks!

 

If it's not going to be insulated and will be unconditioned thats one thing. Treated 2x8s and treated subfloor would be fine for the floor on 16" centers. Being so close to the ground they will be suceptible to mold. Decks are never a good idea when they are that low. You simply won't be able to get under it, and fiberglass insulation would be unwise that close to the ground.

If that isn't acceptable then you need to excavate the entire perimeter, and put in a footing below frost and pour the walls and pad with concrete, then build off that. Crawlspace optional. Depending on the surrounding drainage and any waterproofing you could be creating a problem if you create a crawlspace.