Door Closer Basics
Types of Door Closers
See also: Door Closer Adjustment
A door closer is a spring-loaded hydraulic device that closes a door automatically. The most common kind of door closer is the surface mounted door closer, so called because it is mounted to the surface of the door or header. Also available are concealed overhead door closers that are mounted inside the header above the door or inside the door itself, and floor closers that are installed beneath the threshold. Pictures of the different types of door closers are shown at right.
Surface Mount Door Closers
Surface mounted door closers are by far the most common kind of door closers. They are relatively inexpensive and easy to install. Unlike concealed door closers for which doors are almost always prepared by the door manufacturer, surface mounted door closers need no special prep.
As shown at right, surface mounted closers can be mounted in standard, top jamb or parallel arm configurations. Standard configuration is used on the pull side of the door whereas parallel arm and top jamb installations are for the push side.
Not shown are surface mounted track closers which use a single arm and a slide track instead of the double lever arm shown in the pictures at right.
Non-track surface mounted doorclosers are available with different kinds of arms that perform different functions. These functions are discussed below in the section called, "Arms."
Concealed Door Closers
Examples of two kinds of concealed door closers are shown in photos at right. There is a third kind, the overhead concealed-in-door door closer, but since it is so rarely used I will not discuss it here.
Concealed door closers are always used when a door is "double acting," that is, it swings both ways, and are often used in high traffic applications, such as the front door of a large office building. As you see above, surface mounted door closers are not about to win any beauty contests. Concealed closers offer designers a cleaner look than surface closers.
Floor closers are almost always used with pivot hinges as opposed to butt hinges. Pivot hinges are stronger and more durable than butt hinges.
What You Need to Know to Order
Here is a list of information that you need to know before you order a door closer:
- Interior or Exterior Door?
- Left Hand or Right Hand swing?
- Door closer to be mounted on the push or pull side?
- Door width?
- Pivot hinges or butt hinges?
- What is the door made of? Wood? Hollow metal? Glass and aluminum?
- If there is glass, what is the size of the piece of material onto which you want to mount the door closer?
When you have this information you are ready to call your hardware professional. If you are unsure what kind of closer will best suit your application, your hardware professional can suggest one based on the information above.
In the pictures of surface mounted door closers at the beginning of this article, the closers all have what is called a standard, double lever arm. This arm is pictured at right. Below it are shown a few examples of optional arms that are available to give surface mounted door closers more functionality.
Hold Open Arm
Most door closer arms are available in a hold open version. Usually they work by friction. Opening the door to a certain degree tightens a nut which causes the arm to stick at a point, holding the door open.
Dedicated Parallel Arm
Called by LCN an Extra Duty Arm and by Norton a Parallel Rigid Arm, this arm is for an extra sturdy, parallel arm only application door closer.
Called a Cush'n'Stop arm by LCN and a Closer Plus arm by Norton, this arm doubles as a stop to keep the door from opening too far and perhaps hitting a wall.
At the bottom of the column of pictures of door closer arms is a picture of an LCN 4041 door closer from the LCN catalog, parallel arm mount, on a plate that is called a "drop plate." It is used to provide a surface to which you can attach the door closer when the surface of the door is too narrow to do so. In the illustration, the 4041 is mounted on an aluminum-and-glass storefront door. The aluminum is too narrow, so the 18PA plate attaches to the aluminum of the door and the 4041 attaches to the plate.
About the Author...
Tom Rubenoff has worked for over 35 years in the door hardware industry, first as a locksmith, then as the owner of a locksmith business, and finally as technical sales representative in hardware distribution.
Questions & Answers
We’ve had 2 Dorma TS72 closers detach from the door and the fitter has blamed it on vandalism when we know that this is not the case. What could possibly cause this? The arm stays attached to the door frame and on one of the doors a screw had snapped in half where the closer had ripped away from the door.
It would be helpful to know whether these closers are installed on the push side or the pull side, but I think - because of the apparent force that is being exerted on the mounting screws - that they are probably mounted on the push side and are therefore in parallel arm configuration. Parallel arm mount would be the only mount that would put direct pull on the mounting screws.
If the closers are mounted parallel arm, when the arm is extended until it stops it will, in effect, pull on the closer body. Dorma's instruction sheet on this install actually has almost no words on it and does not say to what degree the door will open when this closer is mounted according to the instructions. It is unusual for mounting screws to pull out of the door or be sheared off, so I think we can conclude that the door is being opened with sufficient force (by a person or because it is being taken by the wind) to 'bottom out' the arm such that it pulls very hard on the closer body, pulling out or shearing off the screws.
Factors that could be contributing are: is it installed correctly? That is, is the closer installed in the right place on the door according to the instructions? Was the arm installed correctly, or was it installed in such a way as to get more power out of the closer than it was designed to have? These are the things I would check first.
Secondly, if there is this much force being exerted against this door, perhaps you might consider adding an overhead stop that will keep the force away from the closer.
© 2008 Tom Rubenoff