Door bottoms are installed on doors to prevent sound, light, and drafts from getting through a gap under a door. Typically there is a small gap between the door and door frame to prevent rubbing and wear on the doors. Even with proper door thickness you may still feel cold air from the gaps. With proper installation, a door bottom can give you a tight seal against the door threshold. Thresholds are installed underneath the door but will not fully block drafts, smoke, or light. There are a few types of door bottoms including automatic door bottoms, and door sweeps. These, as the name suggests, go on the bottom of a door, sealing the small gap between the floor and the door.
Door bottoms can also be used to prevent smoke from moving from one room to another. This can become an essential function in fire situations, helping to keep your commercial property as safe as it can be. There are special automatic door bottoms for fire rated wooden doors. Automatic door bottom hardware is operated by a movable drop-bar seal that is operated by a plunger. The plunger is attached on the hinge side of the door and is activated and deactivated by pressure from the door frame. This allows the door bottoms to have a tight seal but not rub on the floor or threshold.
A door bottom is an effective way to protect your property from moisture, smoke, and air leaks. There is a wide variety of door bottoms and they can be installed on a variety of doors including entry doors, garage doors, French doors, interior doors, and fire rated doors.