Abstract: An awning having a V-shaped cross section is supported by a cantilever which projects from a vertical support. The vertical support is positioned such that one of the surfaces of the awning faces a prevailing wind while another surface is sheltered from the prevailing wind The latter upper surface has an elongated opening through which the wind may flow. The opening is opened and closed by a means of a flap which pivots from an open position for allowing the wind to pass through the opening to a closed position for preventing the wind and rain from doing so. The flap opens at such time as the force of the wind is sufficient to cause it to do so and closes under the force of gravity at other times.