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Metal Roofing from Aluminum to Zinc Part 3: Paint Finishes for Metal

May 15, 2004

WHAT IS “PAINT”?
In liquid form, paint is comprised of
three principal ingredients: resin, pigment,
and solvent. Pigment and resin are blended
in an approximate 50/50 ratio. (The darker
the color, the lower the relative pigment
content.) The pigment’s purpose is to provide
color and to hide the primer and substrate.
The resin binds the coating to the
substrate and provides the weather resistance
and durability properties desirable in
an architectural coating.
Because both pigment and resin materials
are solids, they must be dispersed by
blending with a solvent. The result is a coating
system that can be applied to the metal
in coil form. (A solvent is not necessary for
powder coatings, but the metal claddings
market predominantly uses liquid coatingdelivery
systems.)
The solvent is therefore the vehicle by
which the solids are transported to the
panel surface. It evaporates during the curing
process. The resin becomes a monolithic
film that acts as the “glue,” holding the
pigment particles to the substrate for years
to come, surrounding and protecting them
from environmental pollutants.
WHAT IS “PAINT”?ING
Continuous coil coating is the process
used for factory finishing of aluminum and
steel panels. Coated steel substrates discussed
earlier in this series, including galvanized,
Galvalume, and aluminized, can
all be coated by this method in a wide range
of gauges.
The coil coating method can produce a
superior paint finish under controlled conditions
and at a relatively low cost per
square foot. But the finish must also be
durable and flexible enough to withstand
Editor’s note: This is the third article in a multi-part series about metal roofing in today’s market. The series provides an in-depth
look at materials and their uses, coatings, system designs, and installation techniques. It is reprinted with permission of Metalmag.
The Sycamore Trails Aquatic Center, Miamisburg, Ohio, features a Snap-Clad roof in
Interstate blue with teal colored trim. (Photo courtesy of Petersen Aluminum.)
Awide variety of paint
systems are available
for coated steel and
aluminum roofing. In
this writing, we will look at the
basic coating processes and systems
that represent the majority
of pre-finished applications in
metal claddings.
O C T O B E R 2 0 0 4 IN T E R F A C E •
OBJECTIVES OF COIL COATING
the traumas of forming, fabrication, handling,
and installation. The applied finish
must then meet the numerous demands of
end use, including aging and weathering
appearance criteria, and yet maintain film
adhesion over time.
While it is a misconception that common
paint films offer primary corrosion
resistance, it is generally true that they can
enhance the corrosion performance of the
metallic coating when properly applied.
During coil coating, the flat metal is
pulled through automatic processes that
clean, chemically pre-treat, prime coat,
cure, finish coat, cure, cool, and rewind – all
in a continuous, self-contained, environmentally
safe operation. Such automation,
when compared to other coating methods,
translates into lower costs to the end user.
While line speeds can be as fast as 800 feet
per minute, normal production speeds of
500 fpm for architectural coatings allow up
to 5 acres of metal to be painted each hour!
Because paint does not stick well to
metal, the cleaning and pretreatment
processes are critical. Pretreatment chemically
alters the surface of the metal, making
it more suitable for primer adhesion.
Popular pretreatments for galvanized
steel are traditionally zinc phosphate and,
more recently, complex oxides and dried-inplace
treatments. Zinc phosphate is
thought by most to be more effective as a
corrosion inhibitor at scratches and severe
bends, especially in aggressive environments.
Pretreatments for Galvalume are
chrome and dried-in-place treatments, and
for aluminum, chromium chromate.
Primer application follows the pretreatment
step. Historically, primers have been
epoxy or epoxy-esters. Today, polyester,
polyurethane, and acrylic water-based
primers are being used because they are
more flexible and resistant to ultraviolet
light. The target thickness of the primer is
0.25 mil, and normally ranges from 0.20 to
0.30 mil.
These first steps – cleaning, pretreatment,
and primer applications – are the
most important to ensure film adhesion and
corrosion protection. Pretreatment makes
the primer stick and enhances corrosion
protection, and the primer makes the topcoat
stick. After oven curing and cooling of
the primer, the topcoat is typically applied
at a target thickness of 0.75 mil. The total
dry-film thickness of both coats is 0.9 to 1.0
mil. This two-coat process is the standard of
the commercial claddings industry and by
far the most common system used in North
America.
PAINT RESINS
Paint is designated by its resin type.
Many different coating systems are on the
market, and they all offer different performance
characteristics at widely varying
costs. When we call paint “acrylic,” “epoxy,”
“polyester,” or “urethane,” we are referring
to the resin. Often resins are blended from
several different materials.
The resin gives the finish its mechanical
characteristics, and some resins are more
flexible than others and will tolerate more
severe bending during product fabrication.
The resin also gives the film its gloss and
gloss-retention characteristics as well as
resistance to abrasion, scratching, and dirt
accumulation.
Polyester resins have enjoyed widespread
use due to the broad spectrum of
colors available, their applicability to a wide
variety of substrates, and their low cost.
There was a time when polyester was “low
grade” paint, used primarily for soffit, signage,
and industrial or agricultural applications.
But polyesters are a broad group of
chemical compounds that have diverse
characteristics, and many developments
within the paint industry have resulted in
very resilient, durable polyester resins.
Some of the newer formulations, when
blended with ceramic pigments, can offer
outstanding weathering properties – still
not equal to PVDF coatings, but much more
impressive than thought possible 20 years
ago.
Of course, low grade polyesters are also
still out there and, when blended with
organic pigments, will have rather poor performance.
Caution should be exercised
when desiring premium performance. It is
not unusual concerning low-grade paint to
see an inexpensive bright red polyester on a
southern exposure fade to a medium pink
within five years, or a deep blue fade to sky
blue within the same time. In addition,
severe fading can be non-uniform and very
unsightly.
Silicone-modified polyester (SMP) paint
systems are a blend of polyester and silicone
intermediates. Silicone acts to improve
the gloss retention and weather resistance
of polyester coatings. As a rule, the higher
the silicone content, the better the performance
of the paint. Originally, silicone contents
ranged from 20% to 50%. Due to
significant advances in polyester chemistry,
however, these percentages are less of a
controlling factor, and 50% SMP (once a
premium resin) has not been marketed for
many years.
For the contractor, the cost of an SMP
finish is about 25 to 35 cents per square
foot, perhaps a bit less for white. SMP formulations
are available in a variety of gloss
levels and will retain the gloss longer than
polyesters. Some SMP formulations come
with 20- to 25-year warranties against
chalk and fade, but these warranties will
Most popular architectural paint finishes are two-coat systems, resulting in a dry film
thickness of about 1.0 mil. (Courtesy of Metal Roof Advisory Group, Ltd.)
3 2 • I N T E R F A C E O C T O B E R 2 0 0 4
PAINT RESINS
sometimes specify lower performance levels
than PVDF coatings.
Fluropolymers, known chemically as
polyvinylidene fluoride or polyvinyl
di-fluoride (PVDF or PVF2) are the current
“state-of-the-art” coatings. This resin was
first developed and manufactured in 1962
and produced and process-patented by
Pennsalt Chemicals (later Pennwalt Corp.).
In 1965, it was marketed under the name
Kynar® or Kynar 500®.
Elf Aquitaine subsequently bought
Pennwalt, but in the process, the U.S.
Federal Trade Commission required a
breakup of this production and technology.
At that time, Ausimont USA Inc. purchased
production rights in Thorofare, N.J. (one of
two production facilities), and subsequently
introduced Hylar 5000® to compete with
Kynar 500. Kynar 500 is now produced and
marketed by ATOFINA Chemicals Inc. (formerly
Elf Atochem). For practical purposes,
the two products are, in a generic sense,
alike. The key to Kynar/Hylar performance
can be found in its basic chemical foundation:
The carbon/fluorine bond is one of the
strongest chemical bonds known. The
resin’s chemical formulation (PVDF) makes
it similar in some respects to Teflon (PTFE),
the popular nonstick coating for pots and
pans. It is a slippery finish that enables
most environmental pollutants to wash off
in the rain. This is also why adhesives do
not stick well to it.
Paint using this resin is usually offered
in a medium- or low-gloss finish, with excellent
weathering and color-stability (retention)
characteristics. When formulated with
the “full-strength” 70% PVDF resin content,
these coatings are offered with 20-year or
longer warranties featuring high levels of
protection.
The two companies that produce these
resins sell the resin powder, under license,
to various paint companies. The four North
American paint manufacturers trademark
the resulting paints under their own brand
names.
Trinar® (Akzo Nobel)
Fluoroceram® (BASF)
Duranar® (PPG Industries)
Fluropon® (Valspar Corp.)
To confuse matters further, the paint is
sold to panel manufacturers and coil suppliers
who pin their own trade names on
products utilizing that paint type, including:
Butler-Cote® (Butler)
FP 500
ColorKlad® (Integris, [formerly
Vincent Metals])
PAC-CLAD® (Petersen Aluminum)
Signature® 300 (MBCI)
UnaClad (Copper Sales)
Contractors and designers can find this
profusion of trade names very confusing
when reviewing specifications.
Simply specifying Kynar/Hylar, fluorocarbon,
or PVDF will not ensure paint containing
the 70% formulation, but specifying
“Kynar 500” or “Hylar 5000” will. The number
designation ensures, by resin licensing
arrangements, that paint containing 70%
PVDF resin is provided. The remaining 30%
of the resin is a proprietary acrylic, which
varies from one supplier to the next.
The powder particles of PVDF are
expanded by heat during the curing
process; then they become plastic and
meld, forming a homogeneous film.
Standard PVDF is typically not available
in bright colors because of the matte nature
of the resin and the natural colors of the
ceramic pigments. However, it is still widely
used in architectural applications and is
more expensive for the contractor than SMP
– usually 15 or 20 cents more per square
foot.
It is important to note that various
PVDF systems are available, including two-,
A modern coil coating line represents an investment of tens of millions of dollars and is
capable of line speeds up to 800 feet per minute with 72-inch coil widths and material
thickness up to .135 inch. (Courtesy of Metal Roof Advisory Group, Ltd.)
2 n
This shows the molecular structure of fluoropolymer coatings, their respective trade names,
and a comparison to a polyethylene molecule. These polymers all have similar properties
derived from their atomic structure and fluorine bonds. (Courtesy of Metal Roof Advisory
Group, Ltd.)
O C T O B E R 2 0 0 4 IN T E R F A C E •
three-, and even four-coat types. For specification
purposes, two-coat PVDF is the
industry standard. Over the years, this
author has noticed a direct relationship
between coating performance and the 1-mil
dry coating thickness. A coating applied
under spec or in some cases over spec will
not perform as well as the one-mil finish.
More is not necessarily better.
These facts are also pertinent because
of the higher relative cost of these films,
reduced film thickness, and the cost to the
producer is significantly reduced – but at
what cost to the material’s performance?
End users and specifiers should check film
thickness integrity to be sure they get what
they pay for.
METALLIC FINISHES
Much of the research and development
in PVDF coatings has centered around the
production of metallic finishes, such as
Duranar XL (PPG), Fluropon Classic II
(Valspar), Ultraceram (BASF), and Tri-
Escent II (Akzo Nobel). These finishes have
a high-tech look, with a deep luster and
depth of color and the sheen and reflectivity
of a natural metal.
Traditionally, metallics have been
expensive because they generally consist of
one and sometimes two extra coats. These
finishes typically include a primer, a paint
coat containing metal flakes (usually aluminum),
and a clear PVDF topcoat that protects
against ultraviolet light and oxidation
of the metal flakes suspended in the coating.
As might be expected, the extra topcoat
required for this type of finish adds significantly
to the cost. On most paint lines, the
metal must run through the line twice,
increasing handling expenses. In addition,
the reflectivity imparted by the metal flakes
often results in variegation from panel to
panel.
By substituting powdered mica to the
paint blending process, manufacturers can
now offer two-coat formulations that cost
less to produce and exhibit greatly
improved batch-to-batch and panel-topanel
color consistency. Mica lends the
reflective sheen desirous in a metallic coating
without the reflectivity and weathering
concerns inherent in metal flake. The result
is “metallic” coating that does not possess
the finicky characteristics or high costs of
three- and four-coat metallic systems. And
there is only a slight trade-off in depth of
color and sheen.
Take care when using these products.
Metallic finishes are directional. The
appearance will be different when viewed
from opposite directions. If a piece of flashing
is inadvertently “end-for-ended,” it will
be quite visually distracting. For this reason,
the coater will often code the product
with directional arrows on the backside.
PIGMENTS:
ORGANIC VS. INORGANIC
Pigment – the powder that gives color
and hiding ability to the finish – is either
organic or inorganic in composition.
Sometimes both types must be used to
achieve a certain shade or color. Inorganics,
which are manufactured from complex
metal oxides, have superior color stability
and chemical resistance. They are the same
ceramic pigments that have been used in
the firing of porcelain for hundreds of years.
Metal oxides vary widely in cost, and the
stability of these pigments is not necessarily
the same from one oxide to the next.
In addition, they aren’t available in all
colors, including bright reds and yellows.
On the flip side, white is only available as
an inorganic (titanium-dioxide) pigment;
there is no organic alternative. In general,
paint manufacturers will blend ceramic pigments
with premium resins and organic
pigments with less expensive resins, but
there is no industry mandate to do this.
Perhaps there should be, as cost incentives
to use inferior pigments can be significant.
The higher-cost inorganics include blue,
green, and black. Because black is a component
of almost every applied color, there
is profit to be gained (but performance lost)
by using the less-stable carbon black compound.
By strict definition, carbon black is
organic, but it is a raw element, so it is often
deemed inorganic.
Although PVDF finishes from all producers
consistently use the higher-grade
ceramic pigments, the same cannot be said
of mid- and high-grade alternative resins.
Hence polyester and siliconized polyester
and other resin blends may exhibit wide
variations in color stability from one supplier
to the next. In some cases, a producer
may use a ceramic pigment in one paint
color and an organic pigment in another –
yet label the paint with the same trademark.
Or the product may have a high
organic content with just a smidgeon of
ceramic and be advertised as containing
ceramic pigment.
In general, the “cleaner,” or purer the
color, the more rapidly and drastically the
pigment will fade. Bright red is one of the
worst. When possible, select colors having
muted tones. For instance, if the customer
wants red, suggest a brick red rather than
a fire engine red. A darker shade will not
necessarily fade more than a lighter one, as
long as the color is not pure and it uses
good quality inorganic pigments.
MEASURING AND TESTING
PAINT PERFORMANCE
The primary exposure conditions that
degrade paint over time are sunlight, heat,
and moisture. Certain airborne chemical
pollutants and acid rain can also accelerate
degradation. Because all paints are affected
by this degradation, the only quantification
is how badly and how quickly it takes place.
The components of paint vary in quality,
performance, and cost. If properly applied,
SPECIFICATION REFERENCES —
THE SHORT VERSION
Chalk
ASTM D-659 (Rating scale of 1-10; 10
is best)
Fade
ASTM D-2244 (NBS or DE Hunter
units; 0 is no change)
Weathering
These specifications include many
standards as measured by ASTM procedures
enumerated in the chart on
page 38, with acceptable levels of performance
inherently included.
AAMA 603.8, “Pigmented Organic
Coatings” (conventional paints)
AAMA 605.2 (92), “High-Performance
Organic Coatings” (premium finishes;
includes minimums for chalk and fade)
3 4 • I N T E R F A C E O C T O B E R 2 0 0 4
METALLIC FINISHES
PIGMENTS:
ORGANIC VS. INORGANIC
MEASURING AND TESTIING
PAINT PERFORMANCE
the paint system should last 30 years or
longer in terms of adhesion (resistance to
cracking, blistering, and peeling).
Consequently, when we ask, “How long will
the finish last?” we are really asking, “How
long will it retain its true color and gloss?”
The answer depends on two factors: pigment
stability and resin quality.
Ultraviolet light chemically breaks down
the components of the finish, resulting in
chalk and fade. Moisture exacerbates this
chemical breakdown. Chalk, or the appearance
of a whitish, powdery substance on
the panel surface is the result of a breakdown
of carbon bonds in the finish. It is
rated on a scale of 10 to 1, with 10 being no
measurable degradation. A chalk rating of 9
is not noticeable, while a rating of 7 is quite
conspicuous.
Fade, or color change, is caused by the
gradual breakdown of the pigment and is
measured in N.B.S. (National Bureau of
Standards) or ΔE Hunter units (referring to
the Hunter Colorimeter used to measure
color variation). A lower ΔE rating denotes
higher performance. One unit is the smallest
degree of color change perceivable by
the naked eye. A change of four or five units
is detectable to any observer but generally
not objectionable, provided that the fade is
uniform. Fade, of course is the most common
type of color change, with the color
gradually “bleaching” toward white. But
color change can also occur laterally.
Green, for instance, may become more yellow
or blue.
The rate of both fade and chalk will be
different, depending on the surface’s orientation
to the sun. The consistency of fade is
as important as the rate, but the industry
has not established a unilaterally accepted
standard for this aspect of paint performance.
It may be assumed, however, that
considerable risk is associated with a “bargain-
basement” finish containing poorly
performing resins and
pigments. The resulting
“checkerboard”
effect of inconsistent
fade can be as bad or
worse than accelerated
color change. The
loss of gloss or the
pick-up of dirt can
also pose visual distractions
that contribute
to color
change but are outside
the realm of color
change as normally
measured by the
industry.
The most reliable
test of paint performance
is exposure to
real weathering conditions
over time.
Because of the degrading
effects of
heat, sunlight, and
moisture, the favored
spot on the map for
testing paint performance
is South Florida. Driving around this
area of the country, one may see one of
many “farms” with row after row of fences
containing tens of thousands of metal chips
mounted at 45º to the south sun. Paint
manufacturers use these chips to field test
new products and formulations, and they
closely monitor their performance by measuring
chalk and fade characteristics year
after year.
An industry that is dynamic and inventive
is always impatient to evaluate new
technology. Mother nature takes time, and
time is money – big money. Waiting to market
a new paint technology until it has been
exposed for 20 years is not often done.
But paint performance is not linear with
time, so interpolation from short-term testing
is not reliable in predicting long-term
performance. Because we achieve two units
of fade in five years does not mean we can
expect four units in ten. Therefore, the
industry sometimes relies on accelerated
test methods to evaluate new technology.
One method sometimes used to accelerate
weathering artificially is the QUV chamber,
which applies intense artificial light
(using one of two different ultraviolet bulb
types) along with heat and moisture. A testing
facility outside of Phoenix, called
EMMAQUA (Equatorial Mount with Mirrors
for Acceleration with Water), is a better
method of accelerating weathering because
it magnifies the natural effects of the sun by
using mirrors and sun tracking in an out-
Color change (fade) is measured in NBS Units, or ΔE Hunter
Units. One unit is the smallest degree of fade detectable to a
trained eye. Premium paint warranties usually limit fade to 5
units. (Courtesy of Metal Roof Advisory Group, Ltd.)
O C T O B E R 2 0 0 4 IN T E R F A C E •
door environment, along with induced
moisture. However, both of these accelerated
test methods have been shown to be
inaccurate in some cases when compared
with the real-world exposure tests over real
time.
DO It is appropriate when discussing paint
performance to include some commentary
regarding industry performance warranties.
Unfortunately, it appears that the warranty
wars in paint finishes have begun. A 20-
year warranty used to be the industry standard
for PVDF finishes, and all producers
offered essentially the same warranty.
Claims were rare, and the performance coverage
was oriented to the worst-case scenario:
a 45-degree, south-facing,
medium-blue surface exposed to South
Florida sun and humidity.
Whereas in the past, the warranty might
have been a conservative indicator of
expectable paint performance, this is not
necessarily true today. We are now seeing
25- and even 30-year PVDF warranties, yet
the finish chemistry and technology have
changed little if at all.
While it is true that paint films will perform
much better in most climates and
environments than they do on maximumexposure
test sites, some of these claims
just go too far – with the warrantor perhaps
banking on the warranty documents being
misplaced and forgotten over time. The fact
that a longer warranty is offered is not
always evidence that the product is superior.
Expected performance and conservative
warranty coverage for a PVDF finish is as
follows:
• Color change: 5 or fewer ΔE Hunter
units over 20 years.
• Chalking: A rating of 8 or higher
over 20 years.
In both cases, expected performance
depends on the environment and orientation
of the surface to the sun.
Warranties will normally cover film
adhesion and maximum levels of chalk and
fade within the warranty period. Vertical
surfaces will perform better than horizontal
ones, and warranty language may also
reflect this. Warranties exclude certain conditions,
such as under-film corrosion. There
is a common misconception concerning this
latter point. Many seem to think that if the
metal corrodes, it is a covered failure under
the paint warranty, but this is not true.
These paint films are permeable,
absorbing and releasing moisture cyclically
with exposure and temperature change. If
that moisture is chemically aggressive, it is
possible for the metal to corrode from
beneath the paint film, especially at film
breaches such as cut edges and scratches.
Such a failure is not covered. This is why
the metallic coating is still important, even
when the material is pre-painted. Be sure to
scrutinize warranties when selecting products.
In particular, look for acceptable levels
of chalk and fade in terms of NBS or Hunter
units. We have seen long-term warranties
cleverly written using units that permit a
red roof to turn pink and be covered with
white powder well within the warranty period
and limitations. Read all the fine print to
find any warranty limitations. And be sure
to keep track of the warranty documents for
the full term of the warranty.
Don’t be fooled into thinking that 70%
PVDF from company A will outperform the
same material from company B just
because the warranty offered is longer term.
Likewise, don’t think that SMP performance
will equal PVDF just because warranty language
is similar. Put more faith in timeproven
products than in warranties.
INNOVATION CONTINUES
The paint finish industry is a dynamic
one, and the technology is continually
improving. For example, clear coats are now
available that give depth and sheen to coatings
that were once only available in lowergloss
finishes. Recent innovations in resin
technology have included the development
of thermoset coatings such as Megaflon®,
which uses a 100% FEVE (fluorinated ethylene
vinyl ether) resin called Lumiflon®.
This and other recent resin technologies
have broadened the color spectrum and
gloss levels of fluoropolymer coatings to
include bright, plastic-like colors that previously
would have been available only in
polyester formulations. Also in the works
are new generation polyesters that may
approach the performance levels of PVDF
finishes.
All of these paint systems have their
place. Even low-cost alternatives can be
used successfully in soffit applications or as
architectural accents to shopping mall interiors
and other non-critical applications
where use of 70% PVDF may be considered
over specification. On the other side of the
coin, using a bargain-basement paint system
in an exposed architectural application
for the sake of saving 20 cents a foot is a
3 6 • I N T E R F A C E O C T O B E R 2 0 0 4
Real world exposure testing is the only infallible way to prove paint performance over time.
South Florida is the favored test geography because of high heat, ultraviolet, and moisture
conditions. (Courtesy of Atlas Weathering Services Group, Miami.)
WHAT WARRANTIES COVER?
INNOVATION CONTINUES
disastrous error, shackling the end user to
costly field painting every few years or total
replacement with the material that should
have been used originally. Often, this is a
mistake resulting from specifier and/or
contractor ignorance or haste.
Other resins also have their place.
Plastisol is sometimes used in very aggressive
environments. Unlike most resins, this
vinyl plastic is less permeable because it is
used in “thick film” applications of 4 mils or
more, thus providing “barrier” corrosion
protection as well as pigmentation. Be careful
of vivid colors when using this material,
as its color change characteristic is often
somewhat inferior.
Another recent trend is a result of the
focus on “cool roof” issues. Some pigment
manufacturers have introduced heat reflective
pigments that allow formulation of certain
dark colors to boast increased
reflectivity and emissivity to remain cool. At
least one panel manufacturer is even using
forming methods that preheat the coil to
make the coating more flexible in fabrication.
In this age, any new construction design
requirement asking for field painting or
other air-dried painting of coated sheet
steel and aluminum product is obsolete and
a customer disservice. Field-applied and
other air-dried paints will generally disappoint,
not only from a quality standpoint,
but also from an economic one. Field painting
is far more expensive than coil coating!
Although color matching is made easy
by computer technology, the match of airdried
paint is temporary, and the rates of
fade are much different; hence, after several
years, the detriment to aesthetics can be
quite alarming. Remember this when using
touch-up paint and when using painted
rooftop accessories. In the field, substrate
O C T O B E R 2 0 0 4 IN T E R F A C E •
A Megaflon (100% FEVE) blue, 70% PVDF blue, and a 70% PVDF silver metallic finish.
(Color chips courtesy of PPG Industries.)
preparation is highly critical to paint adhesion
and very difficult to control.
Film thickness is also at the mercy of
the applicator. In the end, even the highest
quality preparation and application methods
cannot be expected to render the service
life of factory-applied premium
finishes.
Pre-painted coil or flat sheet is readily
available for related flashings and guttering
and should be used in tandem with prepainted
roofing sheet. When use of mill steel
shapes in exposed application is unavoidable,
the appropriate solution is a pre-finished
sheet metal shroud as opposed to
attempts to match field-applied paints,
which inherently pose a continual maintenance
problem.
The author thanks Jack Williams, ATOFINA
and Mike Peterson, Petersen Aluminum, for
their assistance in preparing this article.
Rob Haddock, director of the Metal Roof Advisory Group Ltd.,
is a well-known expert and educator in the field of metal roofing
technologies. He is an international metal roofing consultant
and innovator, holding numerous U.S. and foreign
patents. He is a contributing editor for several trade publications,
a member of the National Roofing Contractors
Association, ASTM, the Metal Building Contractors and
Erectors Association, and the Metal Construction
Association. He is also a course author and presenter for RCI,
NRCA, and the University of Wisconsin School of Engineering. Haddock is a past recipient
of RCI’s prestigious Horowitz Award for contributions to Interface journal.
Rob Haddock
3 8 • I N T E R F A C E O C T O B E R 2 0 0 4
SPECIFICATION REFERENCES — THE REST OF THE STORY
Most of these ASTM procedures are not pass-fail, but quantitative in nature, hence
the specifier must know and state the level of performance desired and include the
same as part of a performance specification.
PERFORMANCE ASPECT ASTM PROCEDURE
FILM THICKNESS D-1005
SPECULAR GLOSS D-523
IR REFLECTIVITY D-3363
FLEXIBILITY D-4145
ADHESION D-3359
REVERSE IMPACT D-2794
ABRASION, FALLING SAND D-968
MORTAR RESISTANCE C-267
DETERGENT RESISTANCE D-2248
ACID POLLUTANTS D-1308
SALT SPRAY RESISTANCE B-117
HUMIDITY RESISTANCE D-2247
SOUTH FLORIDA COLOR CHANGE D-2244
CHALK RESISTANCE D-4214
QUVB G-53
ACID RAIN (KESTERNICH)
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AWCI Rewrites EIFS Seminar Content
The Association of the Wall and Ceiling Industries (AWCI) has announced the completion of its revised EIFS seminar
content. The new content, launched in September 2004, came after more than a year of planning and development.
“EIFS – Doing it Right” is a handbook for the course, which leads to national certification for mechanics,
industry professionals, and EIFS inspectors. The latest revision will be the basis for ongoing winter programs offered
around the country.
Since 1918, AWCI has been serving wall and ceiling contractors, manufacturers, suppliers/distributors and others
allied to the field of acoustics, drywall, EIFS, fireproofing, insulation, plaster, steel framing, stucco, and many
other interior and exterior applications. The EIFS education and certificate program was developed in 1998 and has
educated more than 2,300 individuals according to industry standards since then.
For more information, visit www.awci.org.
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