A crossover could have been constructed for that mess. Looks like the salesman screwed up and this was their solution. That looks hideous, it could have been thought out a bit better. I would hate to service that thing since all of the good stuff is on the building side. That just looks lazy! At least they could have painted the duct with a sealant, wait until it starts to rust. The seams aren't even sealed--water infiltration? Wait...my bad...they used foil tape, they are good to go!!!