The document provides an overview of product performance testing for metal roofing systems. It discusses 6 main sections: 1) thermal movement testing, 2) paint finish testing, 3) air, water, and impact testing, 4) wind uplift testing, 5) fire resistance testing, and 6) common metal roof problems. Various ASTM standards and tests are described, including for thermal expansion, water penetration, impact resistance, and fire resistance. Different wind uplift test methods like UL 580, ASTM E-1592, and FM testing are also summarized. Common metal roof issues such as corrosion, staining, rusting, oilcanning, and improper installation are briefly outlined.
4. Thermal MovementThermal Movement
Expansion and contraction is a factor of:
Material type (steel, aluminum)
Temperature differential
Length of panels
Most specify a default of 150 deg temp. differential,
unless greater is specified (COE up to 220 degrees)
Easy rule of thumb is 1/8 for every 10 ft of panel length !
(Steel panels at a 150-degree temperature change)
19. ASTM E-1680: test for air leakage through panels
ASTM E-1646: tests for water penetration into the
panels, simulates wind-driven rain at the panel ribs.
UL 2281/FM 4473: impact resistance test where steel
balls are dropped to simulate hailstones. Class 4 is the
best rating possible, all Alliance panels meet Class 4.
Air, Water and Impact TestingAir, Water and Impact Testing
21. This procedure tests for water penetration into the
panels, simulates wind-driven rain at the panel ribs.
ASTM E-1646 Water Penetration TestASTM E-1646 Water Penetration Test
Suction
22. The Cool Impact Resistance Test
UL Standard 2218
This test, developed and standardized in
1996, was designed for use in evaluating
resistance to impact by replicating the
impact energy of large hailstones on roof
covering materials. The test involves
dropping a series of varying sized and
weighted steel balls from distances
varying from 12 to 20 feet on test decks,
built to replicate actual roof installations.
Micro-Cracking of the top
Galvalume layer---------->
22 gauge Steel
25. The Uplift Failure That Started It All
RICOWI was formed to investigate the wind uplift
failures from Hurricane Katrina.
26. RICOWI: Roofing Industry Commission On Weather Issues
Established in 1990 as a non-profit organization to identify and
address important technical issues related to the cause of wind
damage which include:
Dynamic testing of roof systems;
Importance of sample size for tests;
Role of wind tunnels and air retarders;
Need for acceptable procedures for ballasted systems;
Field data and response team reports;
General lack of communication within the roofing industry
Main sponsor organization is Oak Ridge National Laboratory.
27. What Came Out Of The RICOWI Investigations
It was determined that roofs experience different wind uplift loads
depending on their size, shape, height, location and wind exposure.
Engineers now have to design for three roof wind exposure zones:
28. What Came Out Of The RICOWI Investigations
It was also determined that different geographical locations
experience different nominal (average) wind speeds. A new wind
zone design map was created:
29. There are three industry recognized wind uplift test
methods:
1. UL 580 Class 90
2. ASTM E-1592
3. Factory Mutual
Wind Uplift Test Methods
30. UL 580 Class 90UL 580 Class 90
A measure of quality assurance only it does not
model real world exposure!
Often incorrectly specified as a UL-90 test; it should be
described as UL 580, Class 90
A 10 x 10 assembly of various substrates are subjected
to incremental positive and negative pressures, both
static and oscillating. Note: the test sample is fastened
around the perimeter!!!
Passing assembly must show no joint disengagement,
clip distress, or buckling.
31. UL 580 (contd)UL 580 (contd)
Quote from AISI (American Iron and Steel Institute)
Design Guide:
UL 580 doesnt give realistic panel strength values for
comparing to design wind pressures that a roof may
experience on an actual building. It is considered a
main field of roof simulation but due to the specimen size
and lack of test restrictions to the perimeter of the test
specimen, the panels behave like a pre-tensioned
membrane that results in un-conservative strength
results
32. UL 580 Class 90 Test ChamberUL 580 Class 90 Test Chamber
Pressure is applied to the top and bottom of the panels
33. Time for a Quiz !Time for a Quiz !
What does the 90 in UL-90 stand for?
90 miles per hour
90 pounds per square foot
The number of jobs Roger will sell
this month
34. Quiz Answer
What does the 90 in UL-90 stand for?
Nothing its just their test number.
It could just as easily have been A9JX3
35. ASTM E-1592 Uplift TestASTM E-1592 Uplift Test
Premier test method for evaluating the uplift capacity of
standing seam roof panels. Best method of evaluating
real world performance.
Specimen size varies- 10 x 25, various end conditions
allowed (fixed, floating and open).
Test is run until failure this establishes the ultimate
load capacity of the panel.
Ultimate load is then reduced by safety factor. (1) test
SF = 2.0, multiple tests SF can be reduced depending on
test repeatability. Allowable panel load is now
determined.
37. Factory Mutual (FM)Factory Mutual (FM)
FM Global is worlds largest commercial and industrial
property insurance organization.
Applicable standard for metal roofing is FM 4471.
Achieving a Class 1 rating involves tests for
Combustibility, Wind Uplift, Foot Traffic, Hail, and
Water Leakage.
An FM rating does not mean the roof complies with the
applicable building code or wind pressures!
If FM is not insuring the building why is this
necessary?
38. FM I-90 ?FM I-90 ?
Many specifiers mistakenly call for an FM I-90 rating. (I-90 is
a highway that runs through Chicago) The rating is actually
designated FM 1-90. Clip spacings example:
UC-6 HD 16" x 24 ga (standard clip)
Rating Field spacing (in) Edge Spacing(in) Corner Spacing(in)
1-60 60 50 20
1-75 60 40 20
1-90 50 25 16
1-105 40 20 13
1-120 30 15 10
39. Factory Mutual ExplainerFactory Mutual Explainer
The FM uplift test is similar to ASTM E-1592, in that it
is run until system failure.
The ultimate failure load determines the classification
(1-90, 1-105, etc.) where the 1-xx number is the ultimate
pressure load (psf).
Ultimate failure for metal roofing panels is typically
around 1-120. For typical 1-90 spec, clip spacings would
be 4 ft. in the field of the roof.
There is a difference between FM listing, FM approved,
and FM loading.
40. Factory Mutual Test To FailureFactory Mutual Test To Failure
ALok
Type
Panel
42. UL-790 Fire Resistance Testing
UL-790 includes three test procedures: Spread of Flame,
Intermittent Flame and the Burning Brand. During all
three tests, there can be no flaming or glowing wood
particles falling off the underside of the test deck, the
roof deck cannot become exposed, and portions of the
deck must not fall or break away in the form of glowing
particles.
Roof assemblies with combustible decks (plywood, plank
or tongue and groove) require two additional fire tests:
(1) an intermittent flame and (2) the burning brand
which measures the ability to resist flaming embers.
50. Swarf Rusting Metal Filings
Swarf are rusting metal
filings that have landed
on and melted into the
paint system.
51. Rusting
Rust is scientifically called oxidation, which occurs when oxygen comes in long-term
contact with iron. Over time, the oxygen combines with the metal at an atomic level,
forming a new compound called an oxide and weakening the bonds of the metal itself -
it is a CORROSION problem. If the base metal is iron or steel, the resulting rust is
properly called iron oxide it is not a sacrificial action of the finish.