Garage wall is 10 feet tall, 44 feet long, studded with 2x6 24" O.C. with 1/2" osb on both sides. Want to build a lean to going out 16'. Questions is what to use for a ledger board, size, type? What to use for the joists, and what spacing? What type, size beam to rest the joists on at the 16' end. What size, type posts and spacing to support this beam at the 16' end. It will have a low slope and I get a lot of snow that even if I put metal roofing on it will not slide off but pile up. At the wall I'd like the top of the joists to be at 9' 6" and at the 16' end have headroom at least 7' but would prefer 8'

You need a drawing by a certified architect or building engineer. They will be able to figure load requirements in your area.This will be required by your building department.

Chuck