Rust on car paint on roof top

Did you try waxing or cleaning it off? The only time rust would appear, is if there was damage and something nicked the clear coat and paint and the metal was exposed to the air. Kind of like a stone chip. How large of an area are we talking? any bubbling? Post a photo below.

It's possible that it's rust stains from the shed roof. Try cleaning it as TDolby suggests. Hope that helps! Jim

Make a warranty claim!