Fabricated building outer wall drainage structure

The fabricated building outer wall drainage structure comprises a vertically-arranged main drainage pipe, a plurality of first through holes penetrating through the main drainage pipe in the front-back direction are formed in the rear side of the main drainage pipe, a plurality of horizontally-arranged branch pipes are arranged on the main drainage pipe and communicate with the main drainage pipe, and a plurality of second through holes penetrating through the main drainage pipe in the front-back direction are also formed in the rear sides of the branch pipes; the main drain pipe and the branch pipes are hoses made of polyethylene materials. The structure can smoothly drain gap water in the gap of the fabricated building, and water seepage of the outer wall is prevented. 装配式建筑外墙排水结构，包括竖直布置的主排水管，主排水管后侧设有若干沿前后向贯穿主排水管的第一通孔，主排水管上设有若干水平布置的支管，支管与主排水管相连通，支管后侧也设有若干沿前后向贯穿主排水管的第二通孔，主排水管和支管均为聚乙烯材料制成的软管。本结构可以顺利将装配式建筑缝隙内的间隙水排出，防止外墙渗水。