The invention provides a green flat pitched roof
system and a construction method. The roof
system comprises a structure layer, and the structure layer comprises a root stopping layer (100), a drainage layer (200), a water filtering layer (300) and a planting layer (400) from bottom to top. The root stopping layer (100) is used for preventing the
plant root system from entering a building structure, and an anti-seepage function is achieved. The drainage layer (200) is used for bearing
irrigation water passing through the water filtering layer (300), a drainage
pipe (630) is laid on the drainage layer (200), and therefore the
irrigation water is drained out of the roof
system. The water filtering layer (300) is used for filtering the
irrigation water passing through the planting layer (400). The plating layer (400) is used for supporting
plant growth, and constructing a
green environment for a roof. Multiple planting rows (500) capable of being interconnected are arranged on the drainage layer (200), and roof system modularization is implemented. According to the flat pitched roof system and the construction method, the problems of hard drainage, water and
soil loss, pipeline blockage, high
plant management cost, hard restoration and the like can be effectively solved, a positive effect is achieved, and use and popularization are benefited.