Automatic Drop Down Door Seals - The Monday Minute

Monday, February 17, 2020

The Monday Minute

Door Hardware Specification Tips
for better designers and builders.

One minute a week to help you make better choices.

002: automatic door seals

Keep it down!  I'm trying to work in here!

We all need our quiet and private spaces.

To help create them, here's a quick look at one of the sexiest of hardware types:

the automatic drop seal

You might have specified or seen them on exterior doors or on mechanical room doors. 


Ever been to a dinner party where the "powder room" was within earshot of the dining table?

We've been specifying them in high-end residential interior doors as more clients put a premium on quiet in their environment. Other obvious applications:

  • Doctor's/Therapist's Office
  • Master Bedroom Entrance
  • Home Office
  • Home Theatre
  • Guest Bedroom/Bath
  • Dungeon
Although there are dozens of different drop seal types and features, we'll introduce you here to two models from German manufacturer, Athmer, that can cover most of what you might need. One is mortised in the door, the other is surface-mounted.
They both have these features in common: 

Rated to 52db: If you go through the expense of an acoustic door, make sure you don't lose all that sound through the undercut. 
Parallel Actuation: The seal drops evenly across the entire width of the door. (see video above)

(Stopping here to point out, "even drop" means no grit being dragged over your floor. Other seals drop one side then the other, causing scratching of your floors over time.)
• Can cover up to a 3/4" gap under the door.
• Athmer seals can be deployed UP ^ into the head jamb or ceiling. 
They Work. Forever (actually tested well over 1 million cycles)
Field-adjustable without any tools 
Surface-Mounted - Athmer Schall-Ex L-15/30 FS 

  1. Quick and Easy Installation:  See Video
  2. It's pretty handsome for a drop seal. Available in silver anodized, (also powder-coated white, stainless steel look by request)
  3. No visible fasteners. See #2
Surface-mounted Automatic Drop Seal
Mortised in the Door - Athmer SCHALL-EX L-15/30 WS 

If you've got the luxury of planning ahead. 


  1. Only .60 inches wide
  2. UL Listed
  3. Easy Installation:  See Video
Automatic Drop Seal Mortised in the Door Thickness
SEE MORE ATHMER PRODUCTS (rainstop, sliding solutions)

Entertainment (if you've got the extra time)

The kids are alright...and out of earshot. 

Until next week...

If you need any help specifying these or other door hardware, give us a call.


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