55% Al-Zn is a metallic coated steel created to give exceptionally long life in roof and wall cladding applications. Around 500,000 new and refurbished buildings a year currently use 55% Al-Zn (estimate based on an average 1000 square metres per building). The metallic coating gives an attractive appearance with a pleasant silvery finish and consistent matt finish. 55% Al-Zn is particularly suitable for use as roof cladding sheets or for roof tiles. Field experience indicates an expected life in excess of 30 years before major maintenance. It also makes an ideal substrate for factory coil-coating (pre-painting) or for post-painting if required. The silvery metallic finish has a better level of solar reflectivity than any other roofing material. Roofs in 55% Al-Zn exceed the solar reflection requirements of the United States Environmental Protection Agency’s ENERGY STAR ® roof products program: they will keep buildings cooler, reducing energy use, utility bills and air pollution in hot climates. It offers excellent resistance to acid rain. Can cut roofing costs by up to 20% compared to pre-painted steel. Tests after 23 years exposure in moderate marine and rural environments show that the 55% Al-Zn coating performs better than aluminium-coated steel with twice the coating thickness.