Kingspan factory in Deland, FL, comes this progress photo of our roof panels. Our roof uses KingZip insulated metal panels with a standing-seam joint. We chose 4" thick panels, which will give us an insulating value of R-32 (exceptional by Florida standards). We could have gone up to 6" thick, which yields R-48, but this would be a bit excessive in South Florida.
Each 42" wide panel will hold two solar panels, which adhere directly to the steel surface of the roof panels. The panels have a galvalume finish whose high albedo value (a measure of reflectivity) means they will reflect most of the sunlight that hits them, minimizing the direct heat gain.
The roof panels are cut to length in the factory, which helps eliminate on-site waste and reduce energy wasted in transit (one benefit to prefabrication). The pieces can come in lengths up to 52', the length of a flatbed truck. Our longest pieces are about 32'. We'll write more about the roof when it starts arriving, early next week.