Metal roof provides increased wind resistance when compared to other roofing materials. This is because metal roofing systems use interlocking panels. The disadvantages of metal roofs include the noise created from rain hitting the roof, and, in snowy areas, the tendency of snow to easily fall off the roof and onto pedestrians or property. Originally, metal roofs were made of corrugated galvanized steel: a wrought iron–steel sheet was coated with zinc and then roll-formed into corrugated sheets. Another approach is to blend zinc, aluminum, and silicon-coated steel. These products are sold under various trade names like "Zincalume" or "Galvalume". The surface may
Aluminium-conductor steel-reinforced cable are normally galvanized, or coated with another material to prevent corrosion. The diameters of the strands used for both the aluminum and steel strands vary for different ACSR conductors. ACSR cable still depends on the tensile strength of the aluminium; it is only "reinforced" by the steel. Because of this, its continuous operating temperature is limited to , the temperature at which aluminium begins to anneal and soften over time. Cable which relies entirely on the steel for strength, and so can be used at temperatures up to , is called aluminium-conductor steel-supported (ACSS). The standard steel core used for