Product Product Performance Performance

TestingTestingMarch 16, 2015Roger A. Wallace, CSI, AIAAlliance Steel, Inc.Architectural Products Division

Learning ObjectivesLearning Objectives

Section 1: Thermal MovementSection 2: Paint Finish TestingSection 3: Air, Water And Impact TestingSection 4: Wind Uplift TestingSection 5: Fire Resistance TestingSection 6: Common Metal Roof Problems

Section 1: Thermal Movement

Thermal MovementThermal MovementExpansion 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)

Thermal MovementThermal Movement

Thermal MovementThermal Movement

Thermal Movement FormulaThermal Movement Formula

IceDam

AISI Thermal Expansion ChartAISI Thermal Expansion Chart

Is Thermal Design Important?Is Thermal Design Important?

Low Eave Over Expansion Oilcanning

Penetrations

Thermal Movement In Other RoofingThermal Movement In Other Roofing

Modified Bitumen Roofing Asphalt Shingles

Section 2: Paint Finish Testing

Florida 45-Degree Paint Finish Test BedFlorida 45-Degree Paint Finish Test Bed

Paint Finish Paint Finish HunterHunter Fade Units Fade Units

Kynar Vs. SMP Fade RatesKynar SMP (WeatherXL)

So does having a good fade rate matter?

This was a BLACK roof 5 years ago

Paint Finish Delamination

Paint Finish Chalking

Section 3: Air, Water And Impact Testing

• 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

Suction

Usually 6.24 or 12.0 psf

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

The Cool Impact Resistance TestUL 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

Section 4: Wind Uplift Testing

Does Wind Uplift Really Effect Roofing?

The Uplift Failure That Started It All

RICOWI was formed to investigate the wind uplift failures from Hurricane Katrina.

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.

What Came Out Of The RICOWI InvestigationsIt 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:

What Came Out Of The RICOWI InvestigationsIt was also determined that different geographical locations experience different nominal (average) wind speeds. A new wind zone design map was created:

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

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.

UL 580 (cont’d)UL 580 (cont’d)

Quote from AISI (American Iron and Steel Institute) Design Guide:

“UL 580 doesn’t 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”

UL 580 Class 90 Test ChamberUL 580 Class 90 Test Chamber

Pressure is applied to the top and bottom of the panels

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

Quiz Answer

What does the “90” in UL-90 stand for?

Nothing … it’s just their test number.

It could just as easily have been A9JX3

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.

ASTM E-1592 Test PictureASTM E-1592 Test Picture

Factory Mutual (FM)Factory Mutual (FM)

• FM Global is world’s 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?

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

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.

Factory Mutual Test To FailureFactory Mutual Test To Failure

ALokType Panel

Section 5: Fire Resistance Testing

UL-790 Fire Resistance TestingUL-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.

UL-790 Test Classifications

UL-790 Flaming Brand Test Material

UL-790 Flaming Brand Test

UL-790 Fire Resistance Proof (flying embers do make a difference)

Section 6: Common Metal Roof Problems

Galvanic Corrosion/Dissimilar Metals

The most protective metal will sacrifice itself first – note the copper is still new.

Wet Stack Staining

Swarf – Rusting Metal Filings

Swarf are rusting metal filings that have landed on and melted into the paint system.

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.

Uneven Substrate - Oilcanning

Improper Storage

Don’t Step On The Flashings

Fire Station # 4North Richland Hills, TX

Improper Design: More Pookie Didn’t Help

Mechanical SeamerMechanical Seamer

Ice And Snow Is Heavy

Proper “Avalanche” Valley Design

Why Snow Design Is Important

Before After

Why We Stock Masterflash Pipe Boots

How Does The Water Get Around?

Solution To A Dilemma

Use Touch-Up Paint Sparingly

Most Air-Dry Touch-Up Paints Fade Within Six Months.That’s Why They Come With Little Tiny Brushes!

Thank you for your attention

Any Questions?