Galvalume
®
Galvalume Steel Coil & Sheet Metal
Pre-Painted and Acrylic-Coated Aluminum-Zinc Coated Steel
AZ55/AZ50
Galvalume is an aluminum-zinc alloy coated cold-rolled steel ideally suited for metal roofing and metal wall panel applications. At Metal Alliance we stock Galvalume AZ50 and AZ55 in 24ga and 26ga coil and flat sheet in a variety of widths — with additional gauges available upon request. Choose from a wide range of finishes including acrylic-coated for a sleek natural metal look, or elevate your project with advanced protective metal coatings like Fluropon® 70% PVDF with Kynar 500® and WeatherXL™ SMP — available in over 50 vibrant, durable colors.
New! Galvalume AZ60 is now available for coastal applications. Coastalume™ combines AZ60 and Tedlar® PVF film to create North America's first Galvalume solution engineered and warrantied specifically for coastal environments. Learn more about Coastalume.
BENEFITS OF GALVALUME:
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Outstanding protection against rust, even in harsh environments
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High structural strength with less weight than many shingles or
tile roofing -
Self-healing protection provides sacrificial protection at scratches
or cut edges, preventing rust spread -
Good heat resistance & solar reflectivity which helps reduce cooling costs
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Outlasts traditional galvanized steel by up to two to four times, reducing maintenance and replacement costs
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100% recyclable at the end of its lifespan and often made with recycled steel content
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Available in Mill-Finish and over 60 colors
Galvalume Quick Reference
†For limited warranty information, including detailed coverages and exclusions, contact a Metal Alliance representative. Galvalume® is a registered trademark of BIEC International Inc. Coastalume™ is a registered trademark of United States Steel Corporation. Tedlar® is a registered trademark of DuPont de Nemours, Inc. Fluropon® and WeatherXL™ are registered trademarks of The Sherwin Williams Corporation. Kynar 500® is a registered trademark of Arkema Inc.
What is Galvalume?
Introduced by Bethlehem Steel in 1972, Galvalume® quickly gained worldwide recognition for its versatility, durability, and clean metallic appearance — and earning the trust of architects, manufacturers, contractors, and building owners alike. Known for exceptional corrosion and heat resistance and a high strength-to-weight ratio, Galvalume has proven to outlast galvanized steel in diverse environments by as much as nine times¹.
Produced through a precise continuous hot-dip process, Galvalume features a 55% aluminum, 43.4% zinc, and 1.6% silicon alloy coating applied to both sides of a carbon steel substrate. Available in several coating weights for a variety of end uses, Galvalume for architectural applications is typically produced as AZ50 for painted panels and AZ55 for unpainted. This translates to coating weights of 0.50 or 0.55 ounces per square foot. AZ60, often selected for applications demanding maximum longevity in harsh environments, has a nominal coating weight of 0.60 ounces per square foot offering even more protection.
Permanently bonded to the steel, the aluminum provides barrier protection while the zinc offers galvanic defense—delivering the best of both metals. Silicon allows for better adhesion between the steel and the aluminum–zinc coating resulting in a smoother, more uniform coating that maintains excellent formability.
¹Courtesy www.steelroofing.com
Galvalume features an aluminum-zinc alloy coating comprised of 55% aluminum, 43.4% zinc and 1.6% silicon that is applied to carbon steel.
How Does Galvalume Work?
Both zinc and aluminum have inherent physical and mechanical properties that offer their own forms of corrosion protection.
PROTECTIVE BARRIER: Aluminum is naturally inert and resists corrosion and rust. When applied to steel it is a protective barrier from water and pollutants.
SACRIFICIAL BARRIER: Zinc is more reactive than aluminum. When exposed to the atmosphere it starts to deteriorate, or corrode, sacrificing itself to protect underlying steel.
When combined, reactive properties of zinc and aluminum work together providing underlying steel superior protection compared with uncoated or other alloy-coated steels. Compared to 100% zinc-coated steel (galvanized steel), Galvalume has 2-4 times longer corrosion protection thanks to:
Better Corrosion Resistance When exposed to the environment, the zinc reacts first, forming a thin impermeable layer of oxidized zinc. The corrosive action of zinc extends the time the aluminum layer is left to do its work protecting the underlying steel from attack.
Cut-Edge Protection All metal panel products experience some exposed metal at cut edges or scratches. This can quickly lead to rust of underlying steel because it is no longer protected. However, as zinc begins to corrode in Galvalume, the newly formed oxidized zinc compound will spread to cover cut edges or other areas that become exposed, in effect sealing these areas off from exposure to the environment. Over time, this "self-healing” action results in the corrosion-damaged zinc becoming a barrier layer that is sacrificed in favor of the remaining zinc, leading to prolonged protection of the aluminum and underlying steel.
