I've started construction on my tractor coop, based on the plans for the Garden Ark. I live in Utah, where it's sunny most of the time, can get hot in the summer, and cold and snowy in the winter. My coop will have a little bit, but not full, shade. I like the look and natural light aspect of the white polycarbonate roofing (I've already decided I don't want clear, like the plans suggest), but I wonder if a solid corrugated metal roof would be better. It would provide more shade, but it would also get hotter. There is quite a bit of ventilation through the "ceiling" and the roofing material is suspended above. Does anyone have experience with both materials, preferably in a hot, sunny, climate? Do the white panels still raise the temperature too much (like a greenhouse) in sunny conditions? Or does the heat radiating off the metal raise the temp just as much?