I'm planning on putting up a storage loft in my garage. It will be over the garage door and then run down the side of the garage in an "L" shape. Well that is the desire anyway. I'm on a crawl space so I'd like to utilize the wasted space above the garage door for storage. I already use some for my Jeep Hard Top that I have on an electric winch.
Have seen several designs on the internet and intend to draw from different ones.
Am staying away from attaching to the ceiling joists as I don't want to add to the load that the roof already has on them. (Have been reading some of the posts on here)

and on the net.
This is similar to what I have planned, but I will have to modify it some do to the fact that the right side of my garage door track is bolted to the wall so I can't use a post at the front edge.
The dimentions are roughly 4 or 5 ft deep over the garage door and 18 ft wide. The leg that comes back from there is another 10 feet or so, need to get measurements on that. Have not desided on how wide that portion is going to be, could utilize a full sheet of plywood and stick it out to 8 ft.
http://www.loftysolutions.biz/Garage%20lofts.htm
So thinking of a 6x6 at the two corners on the left and the front right and then again on the very back "L" leg.
Ledger boards along all three walls, not sure if a 2x4 will work for this or if I need to go with a 2x6 laged to the studs. (yes sheet rocked in the garage)
I don't want to be worried about putting weight up here, but there is no more than 4 ft of height up there.
The issue is how to attach the beam on the right side? I had planned to put it on a 6x6 until I took a closer look in the garage and realized the track issue. Don't think putting it on the ledger will work, then I lose another 6".
I'll come back to this issue with a picture or two.
If I could put it on a 6x6, could say 2 2x10's work as a truss? Or do I need to go with something stronger? Not my area at all so I'm looking some help here. Ask away and I'll try to answer your questions.
Thanks!
Mike