The invention is a roof system having panels attached by battens and adjustable hangers. The hangers have a leg, a tail and a hook. The hanger is supported by a batten strip material, typically made of metal with slots. These hangers are permanently secured within the battens and are non removable once the batten is fastened to a roof deck. The hangers themselves are adjustable to different lengths by sliding them within the slot with a predetermined amount of force to accommodate staggered panel edges. This dramatically reduces the labor and costs required to install roofing panels.