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Quest to Capture Door Performance
Spurs Standards Development
by Dean Lewis
AAMA certification goes beyond basic performance assurance
for completed door and window units by recognizing that a door or window
is a complex, interacting system of components that must perform properly
over a long service life. For this reason, as a pre-requisite for their
use in fenestration products that bear the AAMA Certification Gold Label
(extrusions or pultrusions, finishes, glass, insect screening, weatherstrip,
sealants and hardware), must be qualified through separate, independent
testing per the most current versions of the standards and test methods
referenced in the North American Fenestration Standard (NAFS) AAMA/WDMA/CSA
101/I.S.2/A440.
Side-Hinged Doors
For some time, however, the side-hinged door (SHD) has presented a special
and somewhat elusive case for component verification and product certification,
owing to unique properties of both the product and its marketplace.
In terms of the marketplace, the primary issue is that of accommodating
in-field substitution of components—a common practice for doors—and stay
within a meaningful certification protocol for the finished product. While
various groups work to resolve this problem, AAMA has, since 2004, offered
interim certification of side-hinged doors to satisfy mandatory International
Building Code (IBC), International Residential Code (IRC) and Florida
Building Code (FBC) requirements for structural loading and (optional)
impact resistance.
In terms of the product and its operating environment, the 2005 edition
of NAFS was a milestone, being the first door and window performance standard
to establish unique specifications for side-hinged doors. This was made
possible by an innovative performance rating concept and the development
of specialized performance standards and test methods that accounted for
the distinct functional differences and application realities of side-hinged
doors. These differences stem primarily from accessibility requirements,
water penetration and operating frequency.
"In terms of the
product and its operating environment, the 2005 edition of NAFS was a
milestone, being the first door and window performance standard to establish
unique specifications for side-hinged doors."
For example, in terms of operating frequency, while a window
may be operated once or twice a week, a side-hinged door may be opened
and closed a half dozen or more times a day. Doors designed for these
different environments must remain intact and operable under the expected
conditions if they are to maintain resistance to environmental conditions.
AAMA Updates Standard Regard SHD
To address this aspect, AAMA 920-11, Specification for Operating Cycle
Performance of Side-Hinged Exterior Door Systems, recently was updated
for cycle testing of side-hinged door systems and their associated hardware
under accelerated operating conditions. The new edition clarifies the
rate of application of open/close cycles prescribed by the test method,
permitting a range of 12 to 24 cycles per minute at the test lab and/or
manufacturer’s discretion. Each cycle consists of opening the door by
60 ± 5 degrees using a pneumatic/hydraulic piston and then closing
it after a minimal dwell time in no more than 2.5 seconds using a similar
piston or counterweight-and-pulley arrangement (or a self-closing device
if applicable). This is performed on a sample product inclusive of all
components (e.g., frame, threshold, door panel, hinges, weatherstripping
and glass lite, if applicable). Locking hardware may be omitted for the
test, but simulated by an added equivalent weight. The total number of
cycles applied in the test increases with the Performance Class for which
the door is intended, ranging from 25,000 for R Class doors up to 500,000
for AW Class doors—thus simulating operation over a long service life.
The final test report is to include the cycle timing used in the test
within the range of 12-24 cycles per minute.
Dean Lewis serves as chief engineer, certification programs, for
the American Architectural Manufacturers Association in Schaumburg, Ill.
He may be reached at dlewis@aamanet.org.
His opinions are solely his own and do not necessarily reflect those of
this magazine.
DWM
© Copyright 2011 Key Communications Inc. All rights reserved.
No reproduction of any type without expressed written permission.
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