The glass used for greenhouse cover materials is mainly 5mm (domestically produced) and 4mm (imported) thick float glass. 4mm glass is commonly used in Europe, America and other regions, and only the 5mm specification is selected in areas with frequent hail. In China, 5mm thick glass meets the requirements of the civil construction market and has become a commonly used specification for glass greenhouse coverage. With the gradual increase of imported greenhouses and the increasing investment of foreign glass greenhouse manufacturers in China, 4mm glass is gradually being used in China's glass greenhouses. The insulation performance of glass is between that of plastic film and polycarbonate sheets, but it has good transparency. The prices of accessories and sealing materials required for glass greenhouses are relatively high. Due to their high quality, the load on the skeleton increases, and the amount of skeleton used also increases accordingly, resulting in a higher overall cost.