Building waterproof rating

The buildings are divided into four categories as follows:
One type of building is particularly important buildings, such as museums, libraries, memorials, exhibition halls, archives, and particularly important laboratories.
Waterproof and durable life limit is 25; waterproof fortification requirements: three or more fortifications.
The second-class buildings are important buildings. Such as terminal buildings, station terminals, star hotels, theaters, hospitals, shopping malls, and warehouses for storing important materials. Waterproof durability is 15 years; waterproof fortification requirements: two fortifications.
The three types of buildings are ordinary industrial and civil buildings. Such as office buildings, residential buildings, industrial plants, school buildings and general warehouses. Waterproof and durable life limit is 10; waterproof fortification requirements: one fortification.
Four types of buildings are mostly buildings that need to be demolished in three to five years or have low waterproof requirements. Such as work sheds, construction parts processing sheds, car bicycle sheds, warehouses, etc. Waterproof durability 5; waterproof fortification requirements: a fortification.
The classification of building waterproofness reflects the difference between important projects and general projects. The difference in durability and waterproof reliability guarantee rate are different, so the fortification level, the performance of the selected materials and the cost are different. The division of waterproof grade makes the design of building waterproof engineering more reasonable, scientific and economical.