these are interior doors, but same concept. We built them to separate the cold storage part of our shop.... they are 16' tall. And they swing out like a huge safe door....
they are each 16x6' and are made out of 2x6, OSB and sheet rock.
THe hinges are 1" tube with 3/4" shaft. Three hinges per door.
we also built a latching mechanism to hold the doors shut.