Galvanized vs Galvalume Metal Roofing, Which is Better?

What is Galvalume® and why is it used for metal roofing?

This article takes a look at galvalume vs galvanized roofing. Back in 1972 Bethlehem Steel trademarked the metallic coating Galvalume® that is applied to a steel base sheet used in the forming of metal roofing panels.  Galvalume® is an alloy with both zinc and aluminum in it.  Each metal has a unique characteristic about it that enhances the longevity of the metal roofing panel over time.  It a nutshell, the aluminum provides the corrosion protection and the zinc provides the durability.  This combination makes Galvalume® a very good choice for a metal roofing panel even in its bare state.  This metallic coating protects the steel from rusting and perforating.  Now metal roofing panels obviously come in many different colors and even though the paint provides some protection of the steel, the metallic coating provides the ultimate protection.  If you were to just install a bare steel metal roofing panel on your roof without any metallic coating or paint, the panel would begin to rust immediately.

What is Galvanized and why is it used for metal roofing?

When we looked gavalume vs galvanized roofing, it’s important to note galvanized metal roofing is similar to Galvalume metal roofing in that the Galvanized coating is protecting the steel underneath it from corrosion and rusting.  Galvanized coating accomplishes this with the use of just zinc.  When molten hot zinc is combined with steel, the zinc actually combines with the steel to form layers, with a layer of just zinc forming at the top and a layer of just steel on the bottom layer.  Galvanized metal roofing is very durable and scratch resistant, however, it’s life is reduced when it is regularly exposed to rain or salt water.

 

Which one is better?  Galvanized Metal Roofing or Galvalume® Metal Roofing?

When we compare galvalume vs galvanized roofing, although galvanized metal roofing has been proven to be better in certain applications, especially when it comes to animal confinement, Galvalume® metal roofing is the superior product a majority of the time.  Studies show that when used on a residential house that a Galvalume® metal roof will outlast a galvanized metal roof by almost double.  Most Galvalume® metal roofs come with a 25 year warranty if the metal roofing manufacturer is using Galvalume® with a full AZ55 coating.  Despite the long warranty, a Galvalume® metal roof when properly maintained over its lifetime will last in upwards of 30 – 40+ years.

 

Galvalume® is a trademark of BEIC International.