How to attach larger ledger board to smaller house joist
I've attached an image to this posting that may help show the problem I'm about to describe. (Note: the sketch is not to scale)
So I started removing the vinyl siding from my house today to install the ledger board for a new deck we are building. All the joists, beams and ledgers for the deck are 2x12 PT lumber.
The existing house joists are only 2x10. This wouldn't be a major problem except for the fact that I have to account for a 3" step down (we get lots of snow) and then another 1" for the 5/4 decking.
Taking into account these 4" from the top of the house joist that only leaves about 6" to attach a 12" ledger board. In addition, code in my county requires the top lag screws to be 2" from the top of the ledger board. So that means I'm now putting the top row of screws 4" above the bottom of the floor joist which essentially gives me nothing to attach the bottom lag screws into.
I'm trying to figure out what the best way is to attach the ledger to the house in this situation.
FYI: Local building code PDF available here (its only 3 pages)