Abstract: A self storage warehouse facility (10) has a plurality of separate insulated self storage rooms (12) each having an exterior foldable door (14) mounted for movement between open and closed positions to permit access to the insulated storage room (12). The foldable door (14) has a plurality of insulated partitions (50, 52, 54) having rollers (66) mounted in guide rails or tracks (42) for movement. In closed position, the lower partition (54) has a lower tubular seal (74) which seals against the foundation (11) and an adjacent ledge (74, FIG. 4). The entire outer perimeter of the door (14) is sealed against a rubber strip (40) along the side edges and upper edge of the door (14). A tubular seal (72) seals along the bottom edge of the door (14). A solenoid operated damper (82, FIG. 7) in a cool air duct (80) is moved to a closed position by energizing of the solenoid (87) upon opening of the door (14). The damper (82) is opened upon return of the door (14) to a closed position.