Abstract: A flood vent access door assembly having a frame assembly defining a fluid entrance aperture; a door pivotally mounted in said frame assembly, where in the door includes at least one ventilation opening formed through the door; and at least one latching/release mechanism for releasably maintaining the door in a fixed position relative to the frame assembly if a level of fluid is not above a determined level and releasing the door to pivot relative to the frame assembly if the level of fluid is above the determined level, wherein the at least one latching/release mechanism comprises a float means coupled to an elongate release arm for determining the level of fluid and releasing a latch of the at least one latching/release mechanism.

Abstract: A crawl space access door assembly having a frame that can be installed while a foundation of a home or other structure and a door is under construction or retrofitted to an existing structure. The crawl space access door frame assembly is sized so as to accept a removable crawl space access door. Sidewall ribs are formed so as to extend from the outer sides of the first sidewall and the second sidewall of the frame and operate in mating relationship with a groove formed in the blocks used to create the frame of the structure to aid in securing the crawl space access door frame assembly to the structure.