Selecting the Correct Closer for the Job
BY: John Geukens, Commercial Hardware Product Manager
The first consideration should be if the closer is intended to replace an existing closer, or if it is for a new installation.
If it is a replacement closer, what is your customer asking you to provide? An exact match that meets all the specifications and size of the existing closer or are you expected to upgrade the existing closer with one that will meet their current needs?
If you are simply looking to provide an exact replacement, the easiest solution will be to simply buy the same brand and model closer that is currently on the door. But what if you can't identify the brand, your supplier is not able to provide that particular brand, or the closer is no longer available from the manufacturer?
It is important to note the existing closer brand or markings, if available, the closer spring size, and the physical size of the closer and mounting hole dimensions. You should know the physical size and type of door. Also, how will this closer be mounted, and are all of the necessary accessory items, such as drop plates, door arms or special brackets available, or will they need to be replaced.
To make your job easier, C.R. Laurence can provide you with a comprehensive Closer Cross Reference listed by brand, model, specifications and closer size that will allow you to select a proper replacement that should fit the existing prep without requiring new mounting holes and labor.
If the job requires you to select the proper closer for the installation, you must first consider what type of closer would be best for the entryway. You must consider the following factors before determining the closer type:
Type and Location of Opening
Interior or Exterior Mounting
Traffic Type, Volume and Frequency
Type of Door
Door Swing
Size and Weight of Door
Wind or Building Pressure Conditions
The most common types of closers are Surface Mounted, Overhead Concealed and Floor Mounted.
Surface Mounted Closers are the most common and least expensive to install. They are readily available and take very little time and effort to mount. They are easily replaced, and provide a wide variety of features and options that are sometimes not found on other types of closers.
Overhead Concealed Closers mounted in the header are commonly used with storefront applications using aluminum frames and doors. They offer a non-obtrusive, economical means of controlling a door without the expense and corrosion factors associated with floor mounted closers
Floor Mounted Closers are the most expensive to install and are often subject to premature failure due to corrosion. However, they must be considered when dealing with heavy doors or high traffic applications. They provide the most efficient mechanical means of controlling a door, and are able to sustain the most abuse. They are also an important consideration when aesthetics of the opening are a concern. Seldom will a Surface Closer add a pleasing appearance to an opening. When using patch, rail or all glass doors, a Concealed Overhead or Floor Closer is always the better, if not the only choice.
Now that the proper closer type has been selected, there are some important decisions that need to be made regarding the spring size, grade and desired features. Is the door located on the outside or inside? What type of locking device will be used? What type of weather seals and internal building pressures will the closer need to overcome to close the door?
The wider and heavier the door, the larger the spring size required to control the door. Remember it is called a door "closer," so therefore you are attempting to control and close the door, yet allow for a reasonable force required to open the door. Closers are rated by spring size, commonly expressed as Size 1, Size 2, Size 3 and up through a Size 6. Most closers are of a fixed single size that can not be altered and are made to be used with a specific range of door sizes. More and more common today are closers that allow the spring size to be adjusted. The closer can be adjusted to the precise opening and closing force required to control the door under varying conditions, and cover a wide range of door sizes and applications.
One of the most important factors that you will need to consider is a little piece of federal legislation that was established back in 1991, called the Americans with Disabilities Act (ADA).
This legislation requires that in order to allow unimpeded travel of disabled individuals, outside entry doors shall have no more than 8-1/2 pounds of opening force, while interior doors are limited to 5 pounds.
One disadvantage of a mechanical closer is that the inner workings of the closer, and the resistance created by the opening itself, will create enough friction to reduce the closing power of the closer to no more than 50 to 60% of the opening force. This is called the efficiency of a closer and is expressed as a percentage of closing force to opening force. In other words, although your closer may be rated to provide 8-1/2 pounds of opening force, you will be asking the closer to close and control the door with no more than 4 to 5 pounds of force. This is often not enough to overcome a wind condition or latching resistance created by most locks and exit devices. So, although you may be in compliance with ADA regulations, you may have a problem controlling the door, especially in a high wind or pressure application. You may want to consider using an automatic opener or power assist type of closer for these types of conditions.
Closers are rated by standards developed by the Builders Hardware Manufacturers Association (BHMA), and the American National Standards Institute, or most commonly known as ANSI. The standard contains performance and durability requirements for closers conforming to Grade 1, 2 or 3 performance criteria. Among other performance specifications for each grade, the most familiar is the "cycle count" that the closer series has been tested to:
Grade 1 = 2,000,000 Cycles with a minimum efficiency of 60%
Grade 2 = 1,000,000 Cycles with a minimum efficiency of 60%
Grade 3 = 500,000 Cycles with a minimum efficiency of 50%
If you are faced with a high traffic opening, such as a shopping mall or department store doors, it is generally recommended that you use a closer that has been tested to perform under those conditions. If the entry will experience less frequent usage, and is not subject to high stress or wind conditions, a lower grade closer will work just fine. Remember, your customer is expecting that you will provide them with the best closer for the job. Your customer does not want to pay more than necessary, and you do not want to go back and replace the closer you installed, but failed.
Other features and options that are common to most closers include independent adjustment valves to control closing (sweep) speed, and latching speed (last 15° of closing cycle) to accelerate the door to overcome latching or closing resistance due to locks, panic devices, seals, or internal building pressures.
Backcheck is an important feature that is intended to dampen or brake the opening of the door between 75° - 90°. This prevents the door from swinging violently open due to wind or heavy traffic, and is intended to prevent damage to the closer, opening and adjacent structures. One thing that should always be remembered, a closer should never be used as a doorstop. An auxiliary doorstop is always recommended when a positive doorstop is required to prevent the door from opening beyond a certain point.
Delayed Action is a valuable option for health care facilities such as hospitals, nursing homes and public buildings that require doors to momentarily stay open to facilitate ease of progress through the opening for elderly or disabled individuals.
Regardless of which closer is selected, take the time to review the instructions and learn the proper procedure to mount the closer. One of the most frustrating service calls facing a manufacturer or distributor, is when the installer calls to complain that the closer is not working. After a few basic questions, it is determined that the closer was improperly installed and the instructions were thrown out with the box. Most manufacturers and distributors incur an expense to make certain that all of their products are supplied with easy to follow mounting instructions and templates... please use them.
There are other types of closers and accessories for various applications, but for the most common applications faced by most installers, these are the usual considerations when selecting a closer that will best suit your customer's needs.
To view our Closer Cross Reference Chart click here.
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