This is an article about surface-mounted hydraulic door closers. Most door closers have degree-of-opening specifications in their sales materials and/or installation instructions. That is to say, they are designed to allow the door to open to a certain degree. See "Degree Of Opening" illustrated below:
Factors that influence the degree of opening requirements include:
- Is there an adjacent wall or other obstruction?
- Does the door need to clear the opening to comply with the minimum 32-inches required by the ADA (American Disabilities Act) or for some other reason?
In any case, degree of opening is an important factor when selecting and installing a door closer to any opening.
Installation: "Regular" or Parallel Arm
For an explanation of regular, parallel arm and top jamb installation, please see my article on Door Closer Basics.
In regular and parallel arm installations, the installer can determine degree of opening by deciding where to place the closer on the door in relation to the hinges according to the installation instructions. Usually the nearer the unit is installed to the hinge side of the door, the farther the door will open. See manufacturers' original instructions for details.
In top jamb installations, the degree of opening is more an issue of the depth of the reveal. The reveal (illustrated below) is the distance between the face of the door and the inner surface of the door frame or header.
Top Jamb Mount Closer
The above is an illustration of an LCN 4020 series top jamb installed door closer. In the above installation, if the reveal is 2–9/16 inches or less, the door closer can be installed to allow the door to be opened to 180 degrees. If the reveal is up to 4–13/16 inches, the door closer can be installed so that the door can be opened to only 140 degrees.
The deeper the reveal, the smaller the possible degree of opening may be. One way to increase the degree of opening is to use a longer closer arm, if available.
Regular Arm Mount Closer
Above is pictured a Norton 9540 door closer mounted "regular arm mount." The closer body is fastened to pull side of the door and the shoe of the arm is attached to the header. Typical reveal on the pull side is 1/8-inch or less, so it is not a factor.
As pictured, this closer can be placed on the door according to the manufacturer's instructions to open to up to 180 degrees.
For regular arm closers, the main factor that limits the degree of swing is the proximity of a wall that is perpendicular to the door as shown by the illustration below.
In the illustration above, the door cannot be opened to more than 85 degrees of opening due to the proximity of the wall to the hinge side of the door. This condition will likely damage the wall and the cover of the door closer.
One remedy for this is to mount the closer on the push side of the door using either the parallel arm or top jamb mounting options.
One can also install a door stop, but to be effective the door stop would need to limit the swing even further.
Parallel Arm Mount Closer
The Sargent 351 series door closer pictured above is installed in the parallel arm configuration which allows up to 180 degree opening. The potential degree of opening for this push side installation can be complicated the unusual circumstance of a pull side reveal greater than 1/8 inch, such as might be encountered with a center hung door.
Track Arm Closer
The above photo shows a Dorma 8916 T series track arm closer mounted on the pull side of the door. This closer in this installation can be templated to allow the door to be opened 180 degrees. Pull side reveal should not exceed 1/8 inch.
Track closers generally speaking exert less closing force than closers with regular or parallel arms. Maximum door width for an exterior door would be 3 feet for the 8916. Specify the 8956 for doors up to 42 inches wide.
Mounting the 8916 T on the push side in the same basic configuration as shown above, the closer can be templated to allow a degree of opening up to 125 degrees.
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.