Gives exceptionally long life in roof and wall cladding applications, or as roof tiles. Can cut roofing costs by up to 20% compared to pre-painted steel. The high solar reflectivity of the silvery metallic finish means that 55% Al-Zn roofs save energy and make buildings more comfortable and cheaper to run in warm climates. Gives excellent resistance to acid rain. Offers light weight with minimum maintenance. Weatherproof roof systems in 55% Al-Zn can be retro-fitted directly over an old roof, and quickly installed regardless of weather conditions. Because it is particularly suitable for low-pitch roofs, it is a first choice for retro-fitting over an existing non-metallic flat roof. The silvery matt finish is consistent and long-lasting. Available with attractive clear acrylic protection over the silvery finish, to resist surface marking and scuffing. This protection makes construction and maintenance easier. In 23-year exposure tests, sheets in 55% Al-Zn outperform aluminium-coated steels with twice the coating thickness.