Door closers come in a variety of types: in-floor closers, overhead concealed closers, surface mount, power operators, etc. This article will focus on the most common; the surface-mounted door closer.
Door closers perform an important function in the scheme of door operations. The proper opening and closing of doors is related to safety, security and economy. If a door closer is too difficult to push open or slams into a person coming through the door, that person’s safety may be in jeopardy. Also a marked fire exit that has a poorly adjusted closer can cause fire to spread more rapidly or to other areas of a building.
When a door does not fully close and latch after each use, the security of a building can be compromised, allowing unauthorized entry. Finally, if a door stands fully or partially open the heating, ventilation or air conditioning costs will rise.
For any door closer to be effective, the door and frame must be fully functional and in proper operating condition. If the door sags, drags or binds, the closer will not operate properly. Adjustment or replacement of hinges, pivots, lock latches and thresholds must be considered before installing or adjusting a door closer. Only when the door opens and closes smoothly and effortlessly will the closer be able to do its job.
Door closers are rated in sizes from 1 through 6. This rating relates to the spring size, resulting in the power produced by the closer. The type and size of the door and the swing mechanism determine the size of the door closer. A hollow core 32” door will usually require a light duty closer. As another consideration, an interior door will usually require a smaller size door closer than a comparable size exterior door.
Lighter duty closers work in the 1 and 2 range; medium range is 3 and 4, while heavy duty is 5 and 6. Some closers are designed with a fixed rating and can only be used for the purpose at which they are rated. Other closers feature an adjustable rating. These can be set at the closer power required for any given application.
Suggestion: Keep an adjustable size door closer in your service vehicle. This provides the opportunity to make a sale and installation without requiring a second visit or having to take the time to obtain a closer.
Door closer bodies may be of cast or machined aluminum or cast iron construction. Aluminum bodies offer a cost effective closer with normal operation in the light to medium duty applications. Cast iron is generally considered to be more compatible with steel components and resistant to wear over repeated cycling in heavy duty use.
Many units use a rack and pinion operation to provide a smooth operation through the opening and closing cycle. Heat-treated steel pinions create increased strength of the shaft.
Door closer covers may be made from molded plastic painted to complement standard hardware finishes or may be made of metal and powder-coated or plated in standard architectural finishes.
Closers have a rating that determines how far they will open in normal operation. Door opening degrees range from 85 degrees to a full 180 degrees. The specific type of door, frame and application will determine the proper closer.
On doors that need to close every time the door is opened, a Non Hold-Open closer can be used. Hold-Open units will use a friction or detent to hold the door in the open position when the door is fully opened. Hold Open arms are not permitted on fire door openings.
ADA listings for barrier free applications require that a maximum force of 5 pounds of pressure be exerted to open a non-fire-rated interior hinged door. Hand held measuring tools are available that will track the force exerted during installation and adjustment.