Automatic Door Bottom


Technical Information

The 36″ Automatic Door Bottom offers positive lock to smooth floors. Rubber sealing bar is automatically deployed a maximum drop of 3/4″ when door is closed. Can be trimmed up to 2″ for narrower door. The design combines low operating force with an adjustable sealing bar. We recommend you use in conjunction with our Door Jamb Seal.

Automatic Door Bottom Features

  • Aluminum Finish
  • Sponge Neoprene Sealing Bar
  • Fully Adjustable
  • Multiple Track Contour provides better seal to floor
  • Can be installed as surface mounted, half-mortised and fully-mortised

Automatic Door Bottom Specification

  • Height: 2 1/2″
  • Depth: 7/8″
  • Length: 36″ and 32″ (Can be trimmed up to 2″)
  • Finish: Brushed Aluminum
  • Sealing Bar: Premium Sponge Neoprene

UL Classification

Meets UL10B, UL10C and UBC 7-2 (1997) Category J 17L5. Positive Pressure Tested Gasket Material for Fire Doors. Intended for Application to/with listed steel frames and /or classified steel covered composite, hollow metal type fire doors rated up to 3 hours, wood and plastic covered composite type fire doors rated up to 1 1/2 hours , and wood core type fire doors rated up to 20 minutes.

Measuring or an Automatic Door Bottom

  1. Cut the door bottom to the length as follows.
  2. Determine distance between door stops. Door bottom should be cut 3/32” shorter than this distance.
  3. There is a 1/2” block in part when shipped opposite the activating screws. This holds sealing bar in the lowered position as when the “door is closed”.
  4. Note: Only the end opposite the activating screw may be trimmed.
  5. Turn adjusting screws on top of door bottom so the mechanism is withdrawn into the case as far as possible.
  6. Slide neoprene in sealing bar towards the activating screw and cut the door bottom. It is best to apply pressure against the neoprene sealing bar and the 1/2” block to prevent vibration of the mechanism while cutting. Trim the neoprene to about 1/4” longer than sealing bar at each end.

Installing an Automatic Door Bottom Seal on door

  1. To develop full sealing pressure it is necessary for the sealing bar to drop a full 1/2”. These instructions must be carefully followed to ensure this drop is obtained.
  2. With 1/2” block still installed in door bottom, close door and lay door bottom in place on floor. Slide activating screw against stop and transfer attachment screw holes.
  3. Remove door bottom, drill holes, remove 1/2” block and attach part to door.
  4. Open and close door a few times and then adjust door bottom with adjustment screws on the top of case for even pressure across width of door bottom.
  5. Operate the door several times to ensure that the gasketing material is properly adjusted so as not to inhibit the door from self-closing and latching properly.