Stone Coated Steel Roofing

Available in daring splashes of color, flaunting classic contours and traditional styles, stone coated steel roofs are becoming more visible on residential and commercial building exteriors. Its strong composition allows it to withstand the elements, but its elegant aesthetic appeal satisfies even the most refined tastes.

Stone coated steel has made its mark in the roofing industry and continues to offer progressive advantages and benefits to homeowners. Well suited for both new construction and renovation, here is what contractors and homeowners should know about stone coated steel.

COMPOSITION

The composition of stone coated steel roofing systems varies by manufacturer.

The panels are made from structural grade steel. To enhance the corrosion resistance of the steel, it is coated with aluminum-zinc alloy or zincalume. The zinc works exceptionally well in protecting exposed areas such as custom cut edges and drilled holes, and extends the corrosion resistance of the underlying steel.

The aluminum-zinc alloy coated steel has an acrylic coating that is applied to both sides. This acrylic priming system provides a uniform substrate that enhances the adhesion of subsequent coatings.

Next the panel is pressed into shape and a base coat of acrylic resin is applied. This specially formulated coating is made in two colors that blend with the various stone granule colors.

The base coat serves two functions. It provides the adhesive to bond the stone granules to the steel substrate, and it also protects the underlying material from moisture and UV light. Pure acrylic resin, the strongest polymer capable of being made into a water-based paint, provides optimum UV resistance.

To add an attractive finish and provide extra protection, ceramic coated stone granules are applied to the panels. These granules improve the resistance to UV light and ensure maximum coverage of the basecoat.

"The stone granules further protect the steel from the elements and make the tiles aesthetically appealing".

Finally, to complete the composition of the stone coated steel roofing, an acrylic overglaze is applied on the granules to give the panels a semi-gloss appearance. This tough, thin, acrylic finish bonds to the granules and encapsulates them with a coating that provides extra protection.

HAIL

This phenomenon causes widespread concern among contractors and homeowners. Large hail stones can penetrate a roof creating golf-ball sized holes, and has the potential of completely destroying a home's exterior.

Each roof system has its strong points, and stone coated steel is a prominent leader for its hail resistance. Available with the highest hail rating, UL 2218 Class 4 impact resistance, stone coated steel has survived some of the worst hailstorms that have swept through the country.

EARTHQUAKES

Although California is notorious for having earthquakes, they have shaken things up in areas you may not think of, such as New Hampshire, Alaska, Alabama and even Minnesota.

A decade ago, a report was conducted by The McMullen Company Inc., which rated the performance of roofing materials after the 1994 Northridge, CA quake. They found that the roofs with the least damage were made of stone coated steel.

Out of the 122 buildings that were analyzed in Northridge, 93 featured concrete or clay tile roofs, 17 featured stone coated steel, eight featured wood shake roofs and four featured asphalt shingles.

Despite the horrific damage the earthquake caused, the stone coated steel roofs had little structural or roof damage, even in areas of significant destruction. Concrete and clay roof systems displayed the most severe damage, followed by wood shake and asphalt roofing systems.

FIRE RESISTANCE

Aside from roofing options such as wood and asphalt, stone coated steel roofing is a UL-Class A fire rated material, the highest fire rating in the industry. With the devastating effects of fire, stone coated steel's strong resistance to fire is an exceptional benefit that could save homes and commercial buildings from destruction.

WIND RESISTANCE

Stone coated steel has the ability to withstand hurricane force winds, making it ideal for coastal areas, as well as other regions that are exposed to harsh weather conditions. Although it works well in coastal areas, high winds can strike almost anywhere.

Wind warranties for stone coated roofs can be as high as 120 mph. Many stone coated steel roofing systems also use interlocking panels and unique horizontal fastening methods that are usually not an option with other roofing materials.

FREEZE/THAW CYCLING

Water often pools on the roof near cracks and fractures. The freeze thaw cycle eventually allows that water to penetrate the roof and then the attic, walls and ceilings. Freeze/thaw and ice damming are major concerns in northern climates, but they can be prevented with the right roof system.

While other tiles are prone to cracking, splitting and breaking from the strain that this natural climatic change causes, stone coated steel has a non-porous surface, allowing it to resist freeze/thaw cycles.

LIGHTWEIGHT ALTERNATIVE

Although durability is typically accompanied by heavy weight characteristics, such as with slate roofing, this is not the case with stone coated metal roofs. This makes it easier for the contractor to install and puts less stress on the roof deck and structure.

Weighing a mere pound and a half per square foot, stone coated steel is lighter than wood shakes, concrete or slate.

CURB APPEAL

If thoughts of corrugated, red, shiny metal roofs come to mind, it's time to embrace the new generation of metal roofing.
The different profiles can emulate contemporary clay tiles, traditional asphalt shingles and even natural cedar shake.

Both residential and commercial steep slope roofing applications have never looked so good in metal. The array of colors that stone coated steel roofing systems offer can add a unique element to your next roofing project.