Abstract: In highrise residential buildings, venting to remove smoke from corridors is required in case of fire. A method of venting smoke from a multi-floor building by providing a single supply and exhaust venting shaft communicating with each floor, with an air supply and exhaust grille opening into each corridor and communicating with the venting shaft; providing a supply source of pressurized air, and an exhaust source of reduced pressure each communicating with the venting shaft, and damper means for selectively closing or opening the communication of the supply source of pressurized air and exhaust source of reduced pressure to the venting shaft. Under normal conditions where pressure is desired in the corridors, the supply source is operating and the communication of the supply source is open to the venting shaft and the exhaust source communication to the venting shaft is closed.