Abstract: A vapor-air humidifier for air climatizing or conditioning installations is disclosed which comprises a double-wall vapor distributor pipe defining vapor exhaust pipe means. By means of a jacket chamber or space, heated by the vapor or steam, the internal space or chamber of the vapor-air humidifier remains free of condensate due to cooling of the air current. The vapor transfered to the air current is thus removed from the internal space which is free of condensate and there is prevented any spraying of water of condensation. Since vapor exhaust elements are arranged along the exhaust pipe means and are distributed over the entire channel cross-section of the humidifier, there is avoided the formation of vapor layers.