Hi Jason, Got the door installed and ended up installing it directly to the subfloor with, of course flashing underneath and an overhang on the flashing of about 5 inches. Lots of caulk all around the brickmold and on the sublfoor and on the flashing. The bottom of the door is about 1 1/4" above the subfloor which should be OK for the finished 3/4" hardwood floor. Hopefully, this will be fine.
Thanks for the info on where to place the deck height. I've been thinking about that and, being in New England and the deck on the NE side of the house, we'd be better off lowering the deck 7 inches. One more question I have, how do you install the flashing for the deck under the vinyl siding? I understand it needs to be about 2-3 inches under the siding and over the top of the ledger, but how does the siding get secured over it?
By the way, my name is Claudia and I have read many directions on installing a door on-line and also received help at Home Depot. But everyone seems to have their own way of installing one, and, obviously by the posts I've received, I guess it all depends.