a security grate is disposed intermediate a conventional multi - apertured vent on the front of a garage door panel to prevent intrusion through the juxtaposed aperture in the panel . straps or washers serving as a backing plate may be located on the interior of the panel to further hinder unwanted removal of the vent and the security grate from the panel to obtain access to the aperture in the panel . alternatively , the security grate may be disposed adjacent the interior of the panel and then any backing plate variants may be omitted . a cover of insulating material is attachable adjacent the rear of the panel to prevent airflow through the panel aperture and to provide insulation . a transparent or translucent cover may be substituted for the insulating cover to provide illumination when the garage door is closed . a closeable opening may be provided in the cover to permit airflow therethrough on a selected basis . the openings in the security grate may be multi - apertured and rectangular , circular , or other configuration as a function of manufacturing criteria and airflow considerations .