"James "Cubby" Culbertson" wrote in message

Thanks folks for the insights. I hadn't really given much thought to the
metal roofing capturing heat/cold. I live in NM and it get's pretty
darned warm in the summer so maybe I should just stick with conventional
building.

How about concrete? It can be easily done yourself with premade insulated
forms. American Polysteel is in Albuquerque www.polysteel.com