We painted the roof of our Airstream white, and there was a noticeable difference in temps. Friends of ours have an identical Airstream, and we parked them side by side for the test. Our trailer was several degrees cooler inside, and I can tell from pa.inful experience the u painted aluminum skin of our friends' Airstream was a lot hotter in direct sunlight than the white painted aluminum of our roof. I was in shorts on top of both trailers , going from one trailer to the oTher. I can tell you which one I got burns on my legs from, and it was not our white roof.
Meddle not in the affairs of dragons, for you are crunchy, and taste good with ketchup.