The joists for the attic upstairs run parallel to the door. There is nothing above the door but the plywood floor of the upstairs, which is nothing but a small attic for storage. I would not have to cut or modify anything structural to do what I want to do
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If you have rafters instead of trusses, then you can pull it off. You'd probably need to box out an area/cavity around the door so you can keep the attic insulated around that pocket where the door would open up in to.
Depending on how your floor/ceiling is engineered, you may be able to prop the track up off the ceiling instead of hang it from the rafters, which will make it easier.
You'll also need a high lift track and a torsion spring system. Even if you have one today, you'll need all new track and a new spring (due to the additional opening height) - so you may find it easier to just get a whole new door. (Depending on what you have today.)
The other thing you'll need to worry about is the distance the door moves away from the wall. As the high lift door opens, it pushes back and away from the wall. So, that will require some additional space between your joists. You'll also need to do some geometry to make sure you have enough radius for the track to turn over your joists and for the flat panels to also clear that. (Your radius may need to be a foot or more above the joists.)