Alan I saw your post about the forge area. I plan on buiding a forge area, where the peak of the roof is left open about 6 in. each side of the peak, then false rafters about 12 in. above the peak, and overhanging the open space each side of the ridge. You now have natural ventilation. I have seen this design on shelter houses. My pastor built one over his forge. I plan on half walls of native stone with drop-down wooden shutters hinged at the top. The shutters could be closed one side if windy, shut down at night to keep the rain off the equipment, or keep the "critters" out of the shop. Hope I've made this clear. If not clear let me know.