Abstract: A dry vent is provided that permits ventilation of motor homes, travel trailers, or the like, while blocking entrance of rain and small animals through the ventilation duct. The dry vent hereof is especially designed for installation on existing ceiling ports, without modification of the port or the port cover. The dry vent includes a pair of opposed water-blocking sidewalls interconnected by a front structure comprising a pair of spaced apart louvres that define an inwardly, upwardly directed air passing channel.