Abstract: A ventilation system for a building, or other structure includes a roof and an airfoil mounted on the roof. The airfoil includes a tubular member having a longitudinal axis, an inside, an outside, and an elongated opening extending parallel to the longitudinal axis. The air foil includes a leading edge positioned with respect to the longitudinal opening on the outside of the tubular member to create a pressure differential between the tubular member and the leading edge when wind blows past the airfoil. An air duct in communication with the interior of the tubular member extends into the building to enable the airfoil to draw air out from the building in response to the wind.