Volume 6 Issue 6 July 2005
Standards Must Evolve
A Need to Address Changing Applications and Market Demands
by Dean Lewis
If it is to be effective in addressing the performance concerns of architects, specifiers, contractors and manufacturers, product certification (and the performance standards upon which it is based) must go beyond basic testing of completed window units. It must also recognize that a window is a complex system of components—extrusions, as well as finishes, glass, screening, weatherstrip, sealants and hardware—that must perform properly and interact continuously in a completed window unit.
Accordingly, the latest omnibus window and door, AAMA/WDMA/ CSA 101/I.S.2/A440-05, as well as its predecessors (AAMA/NWWDA 101/I.S.2-97 and AAMA/WDMA 101/I.S. 2/NAFS-02), include specific performance requirements that apply to vinyl extrusions and cladding, aluminum extrusions and cladding, and to wood framing members and parts. That’s the first level of verification.
It’s More than the Frame
But it doesn’t stop with framing material. Other applicable industry standards and test methods apply to components. To establish a total quality management system tying together the network of manufacturers of these components and window system fabricators, key component suppliers must assure window manufacturers that their products meet the requisite standards.
Under the AAMA Certification Program’s Component Verification requirements, if a component supplier cannot demonstrate that its product complies with the applicable AAMA standards via testing at an accredited laboratory, the component may not be used in products approved to bear the AAMA certification label.
Setting the performance bar at a high level has the added benefit of helping filter substandard product out of the marketplace.
Hardware is Critical
Hardware is a relatively unsung but nevertheless critical aspect of the product and a good example of the continuous behind-the-scenes effort required to keep the entire window or door system up to modern performance demands.
Performance standards have existed for some time for the operation of hardware components such as sash balances for hung windows, multi-bar hinges for windows, rotary operators for casement, awning and jalousie windows and roller assemblies for sliding glass.
But time marches on, and so does evolving market expectations. As an example, AAMA 906, “Voluntary Specification for Sliding Glass Door Roller Assemblies,” has been revised recently from its 1996 edition and released as the 2005 edition. Both require cycle testing of sliding glass doors by opening and closing the door within a test fixture (simulated track) at a speed of at least 12 inches per second but not more than 36 inches per second (try it–that’s pretty aggressive treatment of a sliding glass door).
Manufacturers should note that there is a significant upgrade between the 1996 and 2005 versions. The cycle testing has been made more rigorous by increasing the number of open/close cycles from 2,500 to 10,000.
Why the increase? Look at the evolution of the product. Sliding doors have changed from the light-weight, single-pane affairs of yesteryear to much heftier products with double-pane insulating glass, thermally-broken and reinforced frames, forced-entry resistant construction and new features. The added weight increases the required performance level of the rollers. If the rollers fail, it can be more than just an inconvenience–it can have safety implications for the building’s occupants.
Similarly, task groups are beginning work on upgrading AAMA 901-96, “Voluntary Specification for Rotary Operators in Window Applications,” and AAMA 902-99, “Voluntary Specification for Sash Balances.” Others are working on developing a new standard for locking mechanisms on swinging patio doors (a.k.a., terrace doors).
This is just a snapshot of a relatively small segment of the continuing effort to improve window and door performance standards and thereby improve the product as a whole. Its real impact comes when model codes reference those standards and building officials begin looking for evidence of compliance–be it a certification label or test reports. At that point, meeting every component performance specification is as much a requirement as passing structural load tests for the entire product.
Dean Lewis serves as manager, product certification for the American Architectural Manufacturers Association in Schaumburg, Ill.
© Copyright Key Communications Inc. All rights reserved. No reproduction of any type without expressed written permission.