Patent ID: 8375664

Claim:
A flood vent for mounting in a building structure subject to flooding, comprising: a frame having an external surface configured to be inserted into an opening in the building structure and having an upper wall and a lower wall longitudinally displaced from the upper wall and a pair of displaced sidewalls extending between the upper wall and lower wall on respective ends thereof; and a buoyant door pivotally mounted between the sidewalls proximate the upper wall of the frame, the door further being mounted to be longitudinally movable a float distance between a first position and a second position, closer to the upper wall than the first position, wherein when the door is in the first position it is not substantially rotatable and when the door is in the second position it is free to pivot, wherein the door pivots within the frame about a rotation axis where the door is mounted to the frame and wherein the rotation axis is longitudinally moved closer to the upper wall when the door is longitudinally moved from the first position to the second position.