Do Metal Roofs Attract Lightning?

Metal Roof and lightning

How safe are metal roofs?

Both commercial and residential structures in Georgia need the best roofing material to withstand the varying types of weather all year long. Some building owners and homeowners consider going with metal roofing these days because of the many benefits they provide. But that consideration also gives them concerns and questions. 

Are metal roofs safe from lightning?

Because we all learn in 8th-grade science, metal conducts electricity. When it comes to metal roofing though, lighting does not make lighting more likely to strike than any other roofing material. In fact, it can make it less likely for it to strike, and it can keep lightning from striking. 

Lightning has been a topic studied for decades, and to date, there is basic information about how it works. However, how it forms or where it will strike, is still a mystery. We cannot predict that metal roofing on a commercial or residential structure will be struck by lightning any more than we can other roofing materials. 

In a quick, short summary, metal roofing is safe. There are not any additional risks if metal roofing is grounded or not, … in most circumstances. So, do you need to ground metal roofs? No. A full roof will ground out a lightning strike through the structure it is installed on and will not cause any interior damage or harm to the occupants. 

Can metal roofs be damaged by hail?

The preconceived thought that hailstones will beat metal roofing is ill-conceived. Most hailstorms do not have large enough hailstones to damage metal roofing. Many metals used in metal roofing like aluminum, copper, or steel are malleable materials. This means they change shape when under stress. What will determine if a hailstorm damages a metal roofing will depend on the storm’s strength?  Factors that should be considered in metal roofing are: 

The Thickness: The thickness of the metal used on metal roofing is the thickness. Metal is measured in gauge and the higher the gauge (number) the thinner the metal. Hence, a 22-gauge metal is thicker than a 29-gauge metal. 

Roof Slope: Cars dent easily in a hailstorm because of the contour. With metal roofing, the lower the slope of the roof, the more likely it will be dented by hailstones. The sharper the slope, the hailstones will more likely be deflected. 

Will metal roofing rust?

Aluminum, steel, and tin are all types of metal that do have an inherent characteristic of rusting. However, a protective coating will allow the metal used for metal roofing to fight the oxidation and rust forming. 

Aluminum and steel are the most common types used for metal roofing. Other types of metal used are copper, stainless steel, steel, and zinc alloys. There are clear differences between them all that can affect the decision of which metal roofing is best. The appearance, cost, durability, and more are all factors that are considered too. 

Which metal roofing is best?

It will all depend on where the structure is located and the type of environment and weather exposure. The following are the four common types of metal roofing materials used today: 

  • Copper Metal Roofing 

Copper metal roofing is often referred to as the grandfather of all metal roofing. Used for hundreds of years, even centuries, it has proven to be an extremely long-lasting material in an ideal environment. It is 100% recyclable soft material and makes for a quiet roof.  However, as a softer metal, makes for a more hailstone vulnerable metal. 

  • Aluminum Metal Roofing 

Ideal for a coastal environment, aluminum metal roofing is resistant to salt corrosion, contrary to many opinions. Aluminum roofs will typically be painted with a coating that gives it a natural patina, some love it, other dislike it. Aluminum is considered a commodity with a fluctuating price based on the market. The strength-to-weight ratio can be too light for areas where hailstorms and high winds are common. 

  • Zinc Metal Roofing

This is an extremely durable metal, patinas over scratches, and has a lifespan of one hundred years or longer. Because it forms easily and can be easily manipulated by roofing contractors to various shapes of roofs makes it a favorite of contractors. The chalking that is a result of Zinc metal roofing makes it one of the least favorite of homeowners and commercial structure owners.

  • Steel Metal Roofing

There are several elements used to make steel. The most common metal roofing material for commercial structures for years and today is incorporated onto residential structures today. The manufacturing process of steel is an energy-intensive process but is 100% recyclable. Within the steel metal roofing are three types of material: 

  • Galvanized Steel 
  • Galvalume Steel 
  • Weathering Steel 

For residential structures, which is better when comparing metal roofing vs shingles? If cost is the major factor, shingles are the economical choice, hands-down. Metal roofing has a higher upfront cost but has fewer maintenance requirements. If you choose metal roofing, you want a roofing contractor that has experience in metal roofing, including how to seal a metal roof. 

Metal Roofed Cabins with lightning

At The Top Of It All 

Does a metal roof lower your insurance? Your insurance company will likely have a favorable opinion of a metal roofing installation. Consider the premium saving to be a financial saving monthly when considering the upfront cost of installation.