Grade Series (Part 2)
Updated: May 6, 2022
Continuing the discussion on door hardware grade from the previous post.
Very brief recap: “grade” indicates the minimum tested mechanical performance of a hardware product, measured in cycles. It is an indicator of durability and cost.
Some points to note about door hardware grade:
Grade is tested differently for different types of hardware (i.e., the test and failure criteria used for hinges is different than that used for closers).
Grades indicate the tested MINIMUM number of cycles that a hardware item can withstand. In some cases, a hardware item may have passed the test for grade 1, and then continued to withstand many more cycles after that. Often in these cases, the manufacturer will include a footnote in the product data indicating the number of cycles that the item actually withstood (rounded to the nearest 100,000 or so).
Not all types of hardware are tested and assigned grades. Generally "grade" is only applicable to hardware items with moving parts (for example, hinges can have a grade, but kickplates do not).
In the context of door hardware, "grade" is NOT a measure of durability in terms of resistance to weather exposure, chemical exposure, etc. It is only a measure of the durability of the mechanism as it performs its intended function under weather-protected conditions.
Grade has nothing to do with fire rating. The tests performed to determine grade are completely different from the tests performed to determine fire rating.
Grade is important to indicate for all applicable types of hardware items in a performance spec. This establishes a baseline level of quality and cost for the bidding contractors.
Generally, grade does not need to be indicated in a prescriptive spec. Since the spec identifies specific model numbers of hardware products, that model number (or numbers, in the case of a three-manufacturer nonproprietary spec) is the requirement, whatever grade it is.
This is the second entry in a multi-part series on door hardware grade. Check back again as the Grade Series continues.
Don't be afraid to ask questions either in the comments section or by contacting me directly. Also if you think I got something wrong, let me know and if appropriate I will make sure to issue a correction.
Architects, do you have a project with door hardware questions? Check out my website www.rshoopconsulting.com. There you can find my contact info, and reach out to set up a call. Let's discuss how I can save you time and money while helping to ensure high quality results for your clients.