GSI grain bin roof ribs are taller, fully double lapped and have four extra reinforcing ledges. The roof ribs, together with corrugated panels and 55,000 PSI high tensile steel, combine to form an exceptionally strong and reliable roof panel system. Each roof panel is manufactured using GSI’s exclusive, fully automated, roll forming line. This insures a precise and consistent fit throughout assembly and helps maintain a tight steel to steel seal between panels. Only GSI offers this level of accuracy in roof panel manufacturing.