CONCEALED DOOR CLOSERS
By Michael Panish
Door Expert Witness
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The overhead or floor mounted concealed door closer is a very common type
of door closer mechanism which is normally unseen and unnoticed. In the
majority of installations, these concealed closers are used on aluminum
glazed storefront doors, hollow metal stand alone, or structural framed
window systems. The concealed door closer design concept was initially
engineered as a self-contained product that featured a center pivot allowing
a variety of door functions with no exterior arm or visible operating
hardware. Other types of concealed door closers have the closer mounted
into either the header or floor area of a door with observable arms that
either exert the force of the closer on the door or limit the door swing
travel. Subsequent development of the concealed closer has led to specifically
functioned products that required advance knowledge of door swing, handing,
and degree of opening prior to purchase and installation. In some concealed
closer products the pivot of the closer interacts with a piece of provided
hardware that allows for limited adjustments of the door travel undetermined
at the time of purchase. But, most devices are specifically limited to
the functions ordered by the contractor or installer. Some concealed closers
only allow single directional control for opening and closing to a fixed
point or door stop. Dual action devices that will swing open and close
in both directions are also common and have specific adjustment limitations.
There are many variations and potential uses that allow special operations
and cycling of doors with these concealed products. Functions such as
hold open, delayed closing, and door swing management are all possible.
With some products, the concealed closer must be specially handed for
either right or left hand installations. Dual action closers where the
door sweeps in either direction are also available with additional hold
open and delay functions. Typically, the choice to use a concealed closer
has to do with the desire to provide a finished clean appearance free
of a piece of hardware positioned on the door or frame of an opening.
In contrast to the box like surface mounted closer commonly found on doors
in hotels, hospitals and other commercial venues, concealed door closers
are completely hidden to most observers.
Depending upon the make and manufacturer of the concealed door closer,
installation of these products places the closer mechanism and attached
hardware in a variety of potential installation locations that require
advance planning during fabrication of the door system. A pocket trough
in the framed door header, top door rail area, or installation into a
channel or floor box or bottom door rail requires advance planning and
fabrication specialties.
Components of a Header Mounted Concealed Door Closer
Includes Closer Body, Installation Brackets, Pivot & Control Arm
Concealed Door Closer for Floor Installation
Includes Hardware & Closer Mechanism
Some concealed closers function with butt hinges for one way traffic, while
others are designed using only pivots to swing the door. The choice of
either type of hinges used limits certain aspects of the door system.
In the case where butt hinges are applied, the door can only open in one
direction as designed. A door stop is usually incorporated into the frame
of the door to prevent damage to the door, hinges and frame. The potential
options that can be associated with a butt hinge installation include
hold open vs. non-hold open functions, delayed closing functions, specific
handing requirements when ordering the concealed closer, and desired opening
swings from 90 to 270 degrees. Where a pivot hinge installation is chosen,
all of the functions mentioned with the butt hinge installations apply
except the travel of the door can be either inward or outward, so no door
stop is installed. Some concealed door closers are generally unhanded
or universally adaptable, but may be limited to a specific opening span
due to the central location of the pivot points.
The use of concealed closers also comes with the same duties and responsibilities
for maintenance that a standard surface mounted closer requires. A common
problem with concealed closers is that owners and property managers frequently
do not understand where the closer is located or what they need to do
to maintain and check the condition of the installed closer. Special installations
may require additional or more frequent service and maintenance. When
concealed door closers are positioned on the bottom of a doorway, and
the pocket for the closer is located in a floor where constant exposure
to moisture from outside weather elements or routine mopping are present,
special added inspections are important.
Dorma Brand Concealed Floor Door Closer
As with any door closer, there are a few different designs that are found
throughout the industry. There are several manufacturers that have merged
over the past few years that provide identical products with different
manufacturer's names and model numbers. Appropriate care must be taken
to replace a defective closer with the proper product. Many of the current
closers look similar to an "inexperienced eye", and may not
be the proper replacement for a defective product.
Four Different Concealed Door Closers
Similar in Appearance / Different in Function
If improper replacement door closers are installed, they can possess functions
that were not present in the originally installed closer and potentially
alter the performance of the door with significant detrimental effects.
An improperly chosen replacement door closer can be over or under powered
creating damage to the door and frame. The closer can have an improper
swing path, allowing the door to over travel and create cosmetic as well
as structural damage to both the door and frame. An improperly handed
replacement closer can cause the door to move in a contrary direction
of travel, and lead to a path of travel or life safety issue. Most good
quality door closers are manufactured to specific standards for ADA and
life safety compliance. Improper or malfunctioning closer mechanisms can
negate the compliance of these standards even though they were originally
in compliance at the time of manufacture. Foreign door closers are often
out of compliance even when purchased new from the manufacturer. It is
essential that appropriate products be used on all installations to avoid
non-compliance that may lead to serious bodily injuries.
Two Similarly Shaped Interchangeable Concealed Door Closers
Each Closer has a Different Function
Most of the concealed door closers I have furnished as a contractor and
observed as an expert during site inspections have been installed in aluminum
storefront or hollow metal door and framed products. Concealed closers
are also used in many other situations. Applications that use wood and
laminated swinging doors in conjunction with specialty wood and synthetic
frame products have also been observed during my expert site visits and
professional installation career. It is essential to note that special
door preparations are needed to properly structure and support the door
closer components in wooden, synthetic, and metal doors and frames alike.
These door pockets and frame recesses are built into the door systems
at the time of the fabrication of the door and frames. Concealed closers
installed into doors and frames made from wood or other products less
resistant to stress and torque than metal products can be problematic.
The fabricator must really understand the potential forces that can be
exerted by a normally functioning concealed door closer and a malfunctioning
concealed door closer. In past personal injury cases where I was retained
as expert, the failure of several fabricators to provide the required
structural integrity has resulted in serious personal injuries.
MAINTENANCE
Many door closer injuries can be attributed to improper maintenance or
lack of proper instruction or awareness that the closer needs attention
on a regular basis. In a commercial environment the volume of traffic
associated with the opening should dictate the intervals for service of
any door closer mechanism. Door closers should be checked daily for proper
attachment, evidence of leaking fluids, force of operation, and wear of
components. The door should be taken out of operation if any problems
are observed. A professional and qualified service provider should repair
or replace the defective door closer or offending door component, and
the problem should be completely corrected prior to allowing further usage
of the doorway.
Article by Michael Panish
www.ConstructionWitness.com