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Part 2: The Role of BHMA Door Standards
By James Piper, P.E.
September 2008 -
Doors & Hardware Article Use Policy
The number of door and door hardware options available has increased dramatically in recent years, making the selection process even more difficult. Fortunately, standards have been developed by the Builders Hardware Manufacturers Association (BHMA) using procedures established by the American National Standards Institute (ANSI). The standards rate the durability of a wide range of door hardware, from hinges and locks to power doors.
One of the key elements of the standards is a rating system for grading various hardware components based on the number of cycles that owners can expect the product to withstand under normal operating conditions. BHMA has established three levels: Grade 1, Grade 2 and Grade 3. Grading levels are product-specific. Manufacturers generally will identify the grade level of a product if it has been tested in accordance with the BHMA standards.
Grade 1 is the highest, most durable level of performance, while Grade 3 is the least durable. For example, a key-in-knob door lock that is rated Grade 1 must be able to complete 800,000 cycles and be able to resist an applied force of 300 inch-pounds (about 25 foot-pounds of torque) without failing. A Grade 2 lock must complete 400,000 cycles and resist an applied force of 150 inch-pounds. A Grade 3 lock must complete 200,000 cycles and resist an applied force of 120 inch-pounds.
Most commercial applications require the use of Grade 1 or 2 hardware. Grade 3 is typically restricted to use in residential facilities. In general, the higher the grade, the higher the cost of the hardware. The typical price difference between a Grade 1 and Grade 2 component is between 25 and 50 percent, while the typical price difference between a Grade 2 and a Grade 3 component is 20 to 30 percent. Offsetting this price difference is the extended service life of the higher grade item.
Does that mean that all applications should use Grade 1 components? Not necessarily. Grade 1 hardware should be installed in all applications where security or heavy use requirements are important. Grade 2 hardware is well-suited for commercial applications involving lighter duty doors where security is not as much of a concern, such as in interior passageways or private offices. Unless there are unusual circumstances with a particular application, the additional cost of the Grade 1 hardware in these instances is not justified.
Understanding the demands that the application will place on the door and its hardware will help facility executives understand why it is important to look beyond first costs when selecting these components. Understanding the rating system as it is applied to doors and door hardware will help in matching products selected to the application requirements. But how does one turn this level of understanding into action, particularly if the process involves competitive bidding?
The most effective way of getting the most out of door and door hardware investments is to follow a program of life-cycle cost analysis. Life-cycle cost analysis considers the total cost of ownership of an item over its service life. This is particularly important for door applications where features that provide higher performance, lower maintenance, and longer service lives translate into higher first costs.
For most door applications, the initial door component purchase represents only 10 percent of the total cost of ownership. The other 90 percent of ownership cost is maintenance. If facility executives are to reduce the total cost of ownership, they should focus on life-cycle costs during the design and specification stages of any new construction or renovation project. Factors that should be considered include installation costs, warranty costs, projected service life, maintenance requirements and maintenance intervals.
It is important to perform the analysis early in the design process. Waiting until it is time to install the doors will only result in compromises, compromises that may result in having to accept components that will not perform optimally in the application.
James Piper, PhD, PE, is a writer and consultant who has more than 25 years of experience in facilities management. He is a contributing editor for Building Operating Management.
Part 1: Door and Hardware Selection Factors