The aluminum is for sealing out any water/moisture/etc and yet it gets hotter in the sun than if it's painted white which reflects the sun's rays better than the weathered aluminum color. About 1997, Lance used white painted aluminum on their higher line product's aluminum roofs. Noticeably cooler in the hot sun. If you can, I'd sure paint the roof white and wash it when dirty to keep it white. So cheap and easy to do!
A superb CC LB 4X4, GM HD Diesel, airbags, Rancho's, lots more
Lance Legend TC 11' 4", loaded including 3400 PP generator and my deluxe 2' X 7' rear porch
29 ft Carriage Carri-lite 5'er - a specially built gem
A like new '07 Sunline Solaris 26' TT