Its durability and cost-effectiveness make these the favored sheet for construction and roofing. In the galvanizing process, one coats steel with zinc that provides a shiny protection against corrosion. This can make materials last much longer than would otherwise have been expected. In particular, when sheltered environments were subject to rust oxidationand sea water attack, this advantage means that higher quality sheeting is desirable even though it may be less attractive financially or take more work by conventional standards.