When shopping for an arch steel building kit or quonset hut, you'll encounter two common steel coatings: Galvalume and galvanized. Both provide corrosion protection, but they perform very differently over a building's lifetime. Understanding the difference helps you make a smarter, longer-lasting investment.
What Is Galvanized Steel?
Galvanized steel is coated with a layer of zinc through a hot-dip process. The zinc acts as a sacrificial coating — it corrodes preferentially in place of the underlying steel, protecting the base metal. Galvanized steel has been used in construction for over 150 years and performs well in most general applications. However, in environments with high humidity, salt air, or acidic conditions, galvanized coatings can deplete faster than expected, leaving the underlying steel vulnerable to rust.
What Is Galvalume Steel and Why Is It Superior?
Galvalume steel is coated with a combination of aluminum (55%), zinc (43.4%), and silicon (1.6%). The aluminum component dramatically improves heat and corrosion resistance compared to pure zinc coatings. In standardized corrosion testing, Galvalume steel consistently outlasts galvanized steel by a significant margin — often two to four times longer in aggressive environments. Duro Span arch steel buildings are manufactured from Galvalume steel, which is why they carry superior longevity and require so little maintenance over their lifetime.
What This Means for Your Building Investment
For a steel building that will sit exposed to weather for 30 to 50 years, the coating on the steel matters enormously. A Galvalume arch steel building kit from Duro Span offers greater long-term protection against the kind of creeping corrosion that can compromise structural integrity over time. This is especially important in coastal regions, the humid Southeast, and agricultural environments where chemical exposure from fertilizers and animal waste can accelerate corrosion on lesser steel products.
Invest in an arch steel building kit built to last. Call 888-848-2011 to learn more about Duro Span's Galvalume steel building kits.