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No reproduction of any type without expressed written permission.

6
Door & Window Market www.dwmmag.com
Fiberglass Reaches the Next Level
Updates to Standard Reflect Material’s Growing Stature
BY RICHARD RINKA
W
indow performance is a
complicated concept. The
big picture is not defined
just by U-value or glass type. It is not
discerned by debating the purported
merits of the different framing mate
-
rial. Each framing material offers its
own unique performance character
-
istics and special advantages for deal-
ing with the performance challenges
posed by climate, building design,
buyer preference and/or budget for
various applications. Any controversy
based on the purported generic supe
-
riority of material type is rendered
virtually immaterial when one stops
comparing the basic characteristics
of isolated samples of unsupported
material and concentrates on the per
-
formance of the complete fenestra-
tion unit.
Standards Matter
There are many framing profile
materials in use today. Their com
-
mon denominator is performance in
their role in a finished fenestration
product. Today’s performance-based,
material-neutral window, door and
skylight standard, the North American
Fenestration Standard (NAFS), aka
AAMA/WDMA/CSA 101/IS2/A440-17
or its predecessors, takes into account
the unique properties, strengths and
weaknesses of all material types.
The profile specifications refer
-
enced in NAFS assist the architect,
contractor, manufacturer, designer
and owner in specifying profiles to
provide a target level of structural and
weathering performance over a peri
-
od of many years.
It has been some four decades since
the standard for PVC profiles emerged
on the scene. Today there are seven
specifications referenced in NAFS for
polymeric profiles. Of these, profiles
made of fiberglass reinforced ther
-
moset (FRT) polymer—more com-
monly known as fiberglass—stand out
as a rising star in popularity, taking
an increasingly larger share of the
window market even during the late-
2000s meltdown.
AAMA 305, the first standard gov
-
erning the performance of fiberglass
profiles, was released in 2000. It estab
-
lishes performance requirements and
references test procedures for dimen
-
sional stability, impact resistance, ten-
sile strength, flexural strength, com-
pressive strength, water absorption,
thermal expansion, heat deflection,
and temperature and color weather
-
ability. These parameters must be ver-
ified through the AAMA profile certi-
fication program as a prerequisite for
certification of completed fiberglass
fenestration units.
Staying Ahead of the Curve
One of AAMAs key missions is to
help bring new materials and prod
-
ucts to the marketplace. AAMA does
this by developing the specifications
and test methods necessary to allow
them to be evaluated on a level play
-
ing field. Accordingly, building on the
previous 2015 version, AAMA 305 has
been updated for 2018.
The primary change is the intro
-
duction of two different product
performance levels. Level I perfor
-
mance is adequate for most fenes-
tration applications; however, for
fenestration applications that require
higher flexural strength and stiffness,
an optional Level II has been estab
-
lished. For flexural strength and flex-
ural modulus, the Level I parameters
remain the same as defined in the
2015 edition. For Level II, they are
more stringent, with loading parame-
ters up to seven times those of Level 1.
All other performance requirements
for Level I and Level II are the same.
AAMA 305 references the most cur
-
rent standards for weatherability of
organic coatings—the “good-better-
best” trilogy of AAMA 623-17a, 624-
17a and 625-17a.
305-18 also references the most
current versions of applicable ASTM
test methods for water absorption,
deflection temperature under flexur
-
al load, thermal expansion, flexural
properties and dimensional tolerance.
Laminates must meet stated adhesive
bond requirements (which have not
changed compared to the 2015 ver
-
sion) as well as the requirements of
AAMA 307, Voluntary Specification for
Laminates Intended for Use on AAMA-
Certified Plastic Profiles.
It also continues the distinction
between critical areas, defined as
those areas of the profile that are
exposed to view when the finished
product is completely installed and in
the closed position. “Exposed areas,
which may be critical or non-criti
-
cal areas, are defined as those that
are exposed to direct sunlight when
the finished product is completely
installed.
The ongoing upgrades to underly
-
ing standards and certifications exem-
plified by the development of AAMA
305-18 not only enable end users to
cut through the fog of material-based
claims and counterclaims; they also
provide a reference point for building
codes.
y
Richard Rinka is the technical manager,
standards and industry affairs for the
American Architectural Manufacturers
Association in Schaumburg, Ill.
A A M A A N A L Y S I S
rrinka@aamanet.org

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© 2018 Copyright Key Media and Research All rights reserved. 
No reproduction of any type without expressed written permission.