The Fire-Resistant Value Of Metal Roofs

Rick Zand

By Rick Zand, New Tech Machinery

Last year, raging fires destroyed much of Lahaina, a historic resort town located on the island of Maui. An image that quickly went viral showed the burnt remnants of homes once populating the scenic tropical coastline. Each had been reduced to ashes and debris except one—a nearly 100-year-old dwelling that just the year before was fitted with a standing seam metal roof.

The Lahaina couple who owns the surviving home credits two reasons their house didn’t suffer the same fate as those surrounding it: Good luck and a metal roof.

The Miracle House

The Lahaina couple purchased their house in 2021 and finished restoring it the following year, tearing five layers of asphalt off the roof and replacing them with standing seam metal. During the fire, they watched as embers scattered across the sky, landing on and igniting asphalt roofs and engulfing homes in flames. In their case, however, metal acted as a deterrent, protecting their home from the onslaught of the firestorm.

Lahaina before the fires

Since the tragic fire that claimed not only property but many lives, the red-roof home has been dubbed the “Miracle House” by several media outlets who’ve reported on it. Amazingly, wood comprises the rest of the structure and the owners had done nothing to fireproof it. The metal roof was enough to keep the miracle house intact.

In the West, fire hazards have increased due to hotter temperatures and drought conditions. The Netflix documentary Fire in Paradise graphically depicts flames devouring a small California town in 2018, leaving nothing but ashes and casualties in its wake. Any structure comprised of flammable materials didn’t stand a chance.

As these affected areas rebuild, metal should be a top priority for every builder and homeowner. Unlike asphalt and wood, metal is naturally fire-resistant.

As 2023 was the warmest year since global records began in 1850, we can expect more fires, especially in the Western U.S., where California, Colorado, Montana, and other states have experienced rashes of wildfires that have devasted homes and communities. According to the Metal Roofing Alliance, every state in the West has experienced an increase in the number of severe wildfires per year for over a decade.

As the lucky couple from Lahaina can tell you, metal is clearly the best option for homeowners looking to build in fire-risk areas. Likewise, homeowners who share environmental concerns can consider the waste produced by asphalt compared with the eco-friendliness of metal.

Lahaina fires

Metal Roofing: Class A Fire Rating

While no type of roof is completely fireproof, metal roofing carries a Class A fire rating, the highest designation by industry standards, which is why it’s recommended by FEMA in fire-prone areas. Metal deflects heat and prevents the spread of flames. Aluminum and zinc alloy roofs are more fire-resistant than galvanized steel or copper, but all carry Class A ratings.

Asphalt shingles can also receive a Class A fire rating. They must be tested to ASTM E108 or UL 790 standards and have a combustion temperature of over 650 degrees Fahrenheit. While metal is more naturally prone to fire resistance, consumers should confirm that their asphalt roofing has been tested to receive a Class A fire rating. Class B is resistant to at least 575 degrees Fahrenheit, while Class C offers little fire resistance with an ignition temperature of 450 degrees Fahrenheit or greater. In fire-prone areas, however, a Class A fire rating is a must.

Limits Of Fire Resistance

Metal roofing does not need testing as it’s automatically categorized as Class A. However, because metal transfers heat, the framing or deck that is part of the roofing system must also be non-combustible. According to MBCI, if the metal roofing is installed over a combustible deck, the metal needs to be tested using ASTM E108 or UL 790. This rule does not apply to 16 oz./ sq. ft. or thicker copper, which can still be considered Class A without testing even when installed over combustible decks.

While Class A designation isn’t always included in building codes, it may be required in some areas, like parts of California designated as wildfire zones.

Also, standing seam roofs, because they lock together at the seams, are more protective than exposed fastener metal roofs. The Lahaina home had a standing seam metal roof.

Along with metal roofing, other factors that can help prevent the spread of fire include fire-resistant doors, shutters, and siding. Also, landscaping around the perimeter of the home (referred to as zone one) should include rocks and non-flammable materials. Shrubs and smaller plants should be spread out in zone two. Zone three can contain large foliage, such as trees and larger plants. These provide some barrier between the structure and fire. Since flames jump, however, the landscaping can’t protect burning materials from landing on roofs.

Metal roofing is becoming more popular, especially in dry, windy climates where fire hazards exist. In the mountains of Colorado, we’re seeing more luxury homes and condos fitted with metal roofs and siding. As the rebuilding of communities takes place, it should be a wide-open market for those in metal construction and a consideration for anyone building a home or renovating the one they have.

Lahaina home after the fire

The Bottom Line: Rebuilding With Metal

It’s estimated that the rebuilding of homes in Lahaina will take years. There are a limited number of architects on the island, building codes are currently under review and will likely see changes, and permits take time to issue, especially given the high number of submissions. The government is working to lead the way while a group of developers has come up with a plan where homeowners can choose from one of five pre-approved house plan options. Pre-approval could save homeowners planning to rebuild thousands of dollars in design and permit costs.

The plan is similar to that of the Los Angeles Department of Building and Safety’s (LADBS) pre-approved list of homes. Most include metal roofing and siding. While Class A asphalt is an accepted option, it still requires testing. The benefits of metal roofs, such as their de facto Class A rating, long life, durability, and minimal required maintenance, should sway builders and homeowners to choose metal over asphalt.

Metal Roofs And Portable Rollforming

Portable rollformers provide savings to contractors and manufacturers by fabricating panels on-site. This cuts down on wait time, transportation costs, third-party manufacturing costs, and the risks of panel damage. Plus, you have less lost time. If a panel gets damaged or turns out to be the wrong size, you simply run another. No ordering and waiting for a new panel to arrive.

Fabricating panels on-site means that you can provide the highest quality metal roofs that will help protect homes from fire damage, last for over 50 years, and require little maintenance. There are now more color and style varieties in metal than ever before. Metal construction is a booming industry, expected to grow from $11 billion in 2022 to over $16 billion by 2032. Metal roofs should be the go-to solution for anyone building in a fire-prone region.

To view this complete article on New Tech Machinery's website, which includes a wealth of related information including videos, visit https://newtechmachinery.com/learning-center/saving-the-earth-with-metal-roofing-part-1-fire-resistance/.

About the author: Rick Zand taught English in the Middle East for nearly ten years. He has worked as a freelance writer, college professor, and university director of admissions. He’s currently the content specialist for marketing at New Tech Machinery, manufacturer of portable rollforming machines. He resides in Denver, Colorado.

About New Tech Machinery

Since 1991, New Tech Machinery (NTM) has helped contractors worldwide gain more control of their projects and profits by manufacturing the world’s finest portable rollforming machines used to form a wide range of metal roof and wall panel profiles, as well as a variety of seamless gutter profiles. To date, NTM has sold machines in more than 40 countries throughout the world.

NTM's seamless gutter machines and metal roof panel machines have revolutionized the metal construction industry by bringing versatile, easy-to-use rollforming products directly to the job site. New Tech Machinery is a proud member of MCA (Metal Construction Association), NRCA (National Roofing Contractors Association) and CRA (Colorado Roofing Association). For more information, visit https://newtechmachinery.com.