I'm just finishing my new shop 40 X 50. I used pallet racks for the framing, walls then screwed the tin to the cross bars. five bars high 8 ft long 12 feet tall, with 3ft of clear on the 50 ft sides at the top ( plenty of light ) The roof is 1 in 12 pitch standard metal building. I have 1 30x70 walk door, 1pair 10x11ft door on the north end and 1 pair 12ft wide x 11 ft door at the south end. I made the doors out of 2in sq tubing and hung them on 5 standard commerchial 5in but hinges. This seams to work ok with weather striping gives a good seal. To do is wiring and plumbing. I have pic but will have to get info on how to send them.