I am starting my build of a metal clad pole barn. 27’ x 48’ x 14’. The trusses are spaced at 8’ on center. How best to insulate the building. I am planning on radiant barrier on outside of purlins under 26ga roof metal. Possibly fiberglass attached between purlins. Wall will be house wrap or radiant barrier on exterior. 1 long wall is west facing with a large garage door. I will have windows up high on 1 long side and end. May install gable fans. Trying to figure if anything else would work better.