Stone Coated Steel Roofing: Benefits and Weather Protection

By Robin Anderson.

Learn why stone coated steel roofing is a durable, lightweight and cost-effective roof system.

Unified Steel™ Stone Coated Roofing by Westlake Royal Roofing Solutions™ is manufactured from Galvalume® steel, then coated with stone granules that are applied with acrylic polymer adhesives. The result is a lightweight (1.5 pounds/square feet), durable and cost-effective roofing system that offers the superior strength of steel and is ideal for new construction, re-roofing and storm-damage applications. Unified Steel is also 100% recyclable at the end of its life on the roof. 

Profiles to match any home’s style 

The natural aesthetic of Unified Steel is ideal for pairing with homes of all architectural styles, from Mediterranean to Contemporary and Transitional. The material is offered in numerous profiles and colors, providing a wide array and variety to satisfy the most discerning of homeowners. Popular options mimic traditional shake, slate, tile and shingle roofing. 

Weather considerations and performance 

When selecting any roof, it’s of paramount importance to consider regional climate and identify the weather conditions most likely to occur where you are installing your roof. Storms, fire, hail, snow and wind are all significant challenges for any roofing material. The good news is that Unified Steel installed with the proper underlayment and attachment process provides safety, comfort and protection from some of the most severe climate conditions. 

Hail 

Stone coated steel roofing is one of the best possible materials for withstanding the devastating hailstorms that impact many regions of the country, providing the highest UL-listed, Class 4 UL impact rating. 

Wind 

Stone coated steel roofing panels are proven to resist wind speeds in excess of 120 miles per hour when fastened properly, making the roofing solution ideal in regions where high winds occur, such as Florida, Hawaii and the Caribbean coastal markets. 

Snow loads, melt and drain 

With its steel composition, Unified Steel can notably carry more weight attributed to snow loads than other roofing options. Additionally, due to the stone coating, snow will not slide off a Unified Steel roof as is common with alternative standing-seam metal roofs. Because the snow melts slowly on a stone coated steel roof into the roof’s gutter system, it creates peace of mind with a safer roof perimeter. 

Ice damming 

Unified Steel offers protection in severely cold climates where ice damming is problematic. These roof systems provide an “above sheathing ventilated” (ASV) space across the entire roof deck. This horizontal and vertical air space provides above-the-deck air flow and insulation that helps mitigate ice damming and icicle formation issues common in heavy snow areas of the country. 

Fire 

As shown by testing results to ASTM-E108, stone coated steel roofing also helps protect structures from fire spread. Unified Steel offers a Class-A fire rating when used with specific underlayment materials, providing extra protection from wind-driven embers, which are common during urban firestorms. 

What the experts have to say 

“I’ve been recommending stone coated steel shingles for over 35 years,” says Steve Davis, sales manager with The Roofing Center, Inc., a roofing solutions provider actively serving the Intermountain West region including the states of Utah, Montana, Idaho, Wyoming and beyond. “With thousands of installations spanning from the Canadian border to Arizona, we have found the shingles to work perfectly in conditions of snow, wind or heat.” 

Jason Mathiesen, president of Smart Roofs for Smart People in South Dakota concurs. “The great plains region of this country, where I am based, has an abundance of extreme weather spanning bitter cold and snow during the winter to wind and hailstorms in the spring and summer. I have discovered that the stone coated steel roofing panels I install hold up to all of it. I consistently have customers with ice damming issues in the winter and hail on their roofs in the summer and their roofs have held up year after year.” 

About the author 

Robin Anderson is the technical and strategy development manager with Westlake Royal Roofing Solutions, the leader in efficient and durable roofing systems and components. Contact Robin at randerson3@westlake.com, visit www.westlakeroyalroofing.com.