An improved vent apparatus that is usable with an electrical enclosure includes a vent flap that is movable between a closed position overlying an opening formed in a wall of the electrical enclosure and an open position wherein at least a portion of the vent flap is spaced from the wall. The vent flap may be held in place in the closed position via gravity or through the use of a retainer such as a spring or a frangible structure. The vent flap is a part of a flap apparatus that is formed as a unitary single piece element that may be stamped from sheet metal, for example, and the flap apparatus includes a number of hinge elements that are rollably disposed on an edge of the wall adjacent the opening.