Metal roofing refers to the form of roofing that uses metal sheet as the roofing material and combines the structural layer and the waterproof layer into one. There are many types of metal plates, including galvanized plates, aluminum-plated zinc plates, aluminum alloy plates, aluminum-magnesium alloy plates, titanium alloy plates, copper plates, stainless steel plates, etc. The surface of the plates can be painted, mainly PE/PE, SMP/ PE, HDP\PE, PVDF\PE four kinds of baking paint treatment, baking paint can strengthen the service life of the board, respectively 5-8 years, 10-15 years, 15-20 years, 20-25 years or more.
The thickness is generally 0.4-1.5mm, and the surface of the board is generally painted. Due to the difference in material and coating quality, some boards can last for more than 50 years. The shape of the board is varied, some are composite boards, that is, the insulation layer is composited between two layers of metal plates, and some are single boards. During construction, some boards are assembled on site after processing in the factory. The roofing project needs to be processed on site. Some insulation layers are well compounded in the factory or can be produced on site. Therefore, the metal sheet roof has various forms, from large public buildings to factories, warehouses, residences, etc. Therefore, the specification stipulates that the applicable range of metal sheet roofing is roofing with waterproof grade I to III.
