ALC roof panels are made into single or porous cavities inside the roof panels, and insulation materials are lined inside the cavities or non connected cavities inside the panels are used to improve the cold insulation performance of the roof panels. So ALC roofs do not require additional insulation materials and can achieve insulation and energy-saving effects, and their convenient construction can greatly shorten the construction period. After the roof panels are installed on the sloping beams of the mountain wall on the top floor of the house, the wing panels are overlapped and covered to prevent vertical seams from appearing on multiple individual roof panels, forming a well integrated sloping roof< br /> ALC roof panels can be directly mounted on steel roof trusses or steel beams. Installing roof panels on reinforced concrete structures can be achieved by welding steel bars onto pre embedded iron; When the roof slope is 1:2, supporting iron pieces must be welded between the three plates and rust proof treatment must be carried out.