Abstract: A roof vent comprises a base defining an air outlet/inlet portion, a cover having at least one exterior louvre for air flow, a side wall connecting the base and cover, and an interior louver between the exterior louvre and the air inlet/outlet portion with at least one and preferably two strips having slats configured such that matter passing through the vent must substantially traverse the interior louvre. The interior louvre is preferably perpendicular to the exterior louvre. The interior louvre contacts the base and the cover to provide support along with the side wall. A supporting rib may be added for additional support. The cover preferably has a second exterior louvre. A second interior louvre is located between the second exterior louvre and the air inlet/outlet portion such that matter must substantially traverse the second interior louvre if it is to pass through the vent via the second exterior louvre.