And The present invention, more particularly concrete, light-weight steel construction, and the inner wall made of a block or the like, structural to the to the inner wall is a distance away to the outside parallel to the veneer brick outer wall of the uptake of the building outer wall, in the structures made of a heat insulating material interposed between the inner wall and the outer wall, and a protruding to the inside at the top between the brick veneer both sides bent outlet; Communication is possible to connect to said outlet and an inclined position between the connecting brick veneer; And communication can be connected to the connection portion, to be located at the bottom between the opposite side consists of a brick veneer uptake consisting of a bent inlet. The present invention is the penetration of rainwater by folds from the outside formed on the can may, as well as uptake prevented to ensure the smooth ventilation of air between the inner and outer walls of buildings that bleaching occurs between the inner wall and the outer wall It provides that prevents effective.