Choosing The Best Type Of Steel Roofing: The Difference Between Galvanized And Galvalume Steel Roofing

In the past 10 years, the roofing market and industry has changed substantially with the introduction of steel roofing. Metal roofing has a market share of 10% for reroofing projects, and metal roofing now accounts for 5.5% of all roofing. What's more astounding is that various market studies have shown that 47% of all households are interested in switching over to metal roofing due to the many benefits that can be obtained. You can choose between aluminum and steel for metal roofing; however, steel has always been the more sought after option, and is offered in either the galvanized or Galvalume form. Most consumers are often confused about the differences between the two, and it is definitely worthwhile to explain.

What Is Galvanized Steel?

Galvanized steel roofing shingles are one of the most popular options on the market. The underlying steel is coated with either a single layer of zinc or aluminum. The protective coating is superficial and will wear off. Due to this reason, galvanized steel roofing require more maintenance, and additional layers of coating may be applied after decades to protect the condition of the shingles. It can offer several unique advantages including: 

  • cost efficiency. In comparison to Galvalume steel, galvanized steel may be cheaper.
  • high strength. 
  • comes in more styles and designs than Galvalume steel, and will be more aesthetically pleasing.

Galvanized steel is less resistant to corrosion, and is not recommended for coastal regions where humidity is inevitable. 

What Is Galvalume Steel?

Invented by Belthehem Steel in 1972, Galvalume steel consists of a steel coil that has been coated with a metal alloy that is made from 45% zinc and 55% aluminum. Galvalume steel has a smoother appearance in comparison to galvanized steel. It can be used in a variety of environments, but not in or around concrete or mortar, both of which are extremely alkaline. The durability of Galvalume steel will be dependent on the thickness of the alloy coating that has been applied. Regardless, Galvalume offers can offer several unique advantages over galvanized steel including:

  • corrosion resistance and heat resistance from the increased concentration of aluminum in the alloy.
  • rust resistance, as the steel cannot be easily reached due to enhanced protection by the aluminum.
  • enhanced barriers that will prevent the underlying layer of steel to be exposed to the environment and to the elements.
  • ease of installation in comparison to galvanized steel. 

There are several different types of Galvalume steel roofing shingles available on the market. The differences mainly lie in the type of alloy that is placed over top.

What Are Advantages That Both Offer?

Regardless of whether you go for galvanized or Galvalume steel, you will be able to reap several benefits which include:

  • increased energy efficiency within the home, as the steel roofing will act as insulation and prevent energy from leaking out.
  • less need for roofing support. Steel roofing is extremely light, and will not require additional supports to be added into the attic to prevent the roofing from collapsing.
  • value retention. Even if you are to replace your roofing at a later date, the metal from the steel shingles can be scrapped and resold on the market. In short, your roofing will be able to retain some value in comparison to other materials, like slate and asphalt, which cannot be resold.

Both types of steel also contain about 35% recycled material, which makes it extremely environmentally friendly. Steel roofing is great for those who are conscious about their carbon footprint on this planet.

While both galvanized and Galvalume steel roofing are able to offer similar benefits, they are generally recommended for different environments and elemental conditions. If you are unsure of which option may be best, you should consider consulting with a roofing professional in order to receive some professional advice that may help you make a better decision.