Just built a house with attached garage. 3 big, heavy garage, doors. 2 of them are
16’ high. I too wanted the jackshaft openers. They delivered tee bar units. I was ticked off as I already installed all the wiring for the jackshaft units. They subsequently sent me one jackshaft unit which I installed on one of the smaller doors. The door distributer came out to the building site to discuss the mix up. Now understand, they supplied the doors and openers. The rep took one look at the door that had the jackshaft opener installed and stated that this opener is not rated for the door and in fact a safety issue. I asked him to explain. Since the jackshaft is directly tied to the torsion shaft, if one or both cables break, that doors is coming down. That got my attention, as these doors are in excess of 700lbs! With a tee bar unit, you lose a cable, the tee bar attachment is going to hold the door in place, probably cocked in the track, but not drop to the floor. Needless to say, I installed three tee bar units on these doors. A pain in the but as my garage walls are 19’ tall and I am not a fan of heights.