Jim, when we bought our bus in 1998 we put up a pole barn by Cleary. We went with a 30 X 50 X 14.
It has a 13H X 15W sliding door. We have no heat in the building.
The Bus's wabasto is left on and the exhaust is ran out the building by a 5' piece of 1 1/2" steel flex tube.
My thermostats (2) are set at 35 degrees in the water bay.
I have thought of using electric heat for the water bay, but if our electricity go off, which it does, (we live out in the country. I would
have to remember to turn the wabasto on.
PS... Our bus says 12' 7" on the dash.