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About Automatic Door Bottoms

An Automatic Door Bottom (ADB) is a simple, yet effective way to create a strong and reliable seal at the bottom of doors to prevent infiltration of drafts, sound, smoke, flames, light and insects. These door bottoms have heavy duty sealing properties that will adapt to your floor condition, ensuring a tight seal against the floor or saddle, even when inevitable shifting and warping of the door occurs.

We have a large variety of high quality Automatic Door Bottoms to suit your specific needs. Our standard door bottoms are available as a Surface Mounted, Semi-Mortised and Fully Mortised application. ADB can be purchased in many metals and finishes, with different seals and are custom cut to size.

Mounted flush to the front of the door
Mounted into the notch out on face of door.
Mounted into notch out on bottom of door.

How it Works:

As the door is closed, an adjustable "plunger" is compressed against the door frame, activating a concealed flat spring mechanism. This mechanism drops the seal smoothly from the housing in a scissor-like motion as illustrated below. The door seal compresses tightly even on uneven surfaces and retracts automatically when the door is opened.

The concealed spring mechanism causes the insert seal to activate on the hinge side first, see image below.  It prevents the seal from dragging along the floor or threshold while the door is being closed to avoid door hang-up or closing delay.

Our Automatic Door Bottoms seal gaps of .3" - 1", see product details for measurements specific to each product. The seal can be easily adjusted to conform to your gap size

Applied on a Wooden Door:

Specialized Automatic Door Bottoms:

We have many ADBs that can be applied in specialized conditions, such as for Sliding Doors or Light Spring for ADA Access Doors.

More Information:

Click here to view all our Automatic Door Bottoms.