Are Metal Roofs Dangerous in a Lightning Storm?
Storm season is in full swing in Colorado. As metal roofs become more popular and sophisticated, questions have arisen as to their safety during a lightning storm. Metal is, after all, an excellent conductor of electricity. Is it possible that a metal roof can attract lightning strikes during a storm?
The Science of Lightning
Lightning develops inside a storm cloud. Initially, air acts as an insulator between positive and negative charges within the cloud and between the cloud and the ground. However, as a difference in charge builds up, the air is no longer able to provide this barrier. This results in a rapid discharge of electricity, aka lightning.
The electric discharge may be between opposite charges within the cloud (Intra Cloud Lightning), or it may occur between opposite charges in the cloud and on the ground (Cloud to Ground Lightning).
Lightning Facts
- Lightning generates heat that can be as much as five times hotter than the surface of the sun.
- On average, lightning strikes the US about 25 million times per year.
- About 50 people per year are killed by lightning strikes
- Lake Maracaibo in Venezuela has the highest rate of lightning strikes in the world. Storms may last for ten hours and the lake can receive up to 40,000 strikes in one night.
- Lightning can be up to 90 miles long.
Are Metal Roofs Hit More Often?
Metal roofs are no more likely to be struck by lightning than any other home in your neighborhood. Contrary to popular belief, lightning is not attracted to certain materials. When it is ready to strike, it will, regardless of what happens to be in the way. The electrical current will, however, be greater in paths with less resistance.
Trees and buildings are better conductors than air, so lightning tends to strike these objects if they are in the general area of the storm. In other words, the object that is struck depends on its size and location, not what it is made of.
Metal Roofs May Actually Be Safer
All homes are a relatively safe place to be during a lightning storm*. You may be relieved to know, however, that your metal roof may actually be even safer than traditional shingles.
Due to the superconducting nature of metal, lightning has a quick and clear way to the ground. In addition, metal roofs are non-combustible, so your home may also suffer less damage if struck.
*There is a risk of injury in your home during a storm if you are in contact with any of your electrical appliances (especially landline phones) or metal plumbing. Switch off appliances before the storm hits and avoid using the bathroom/shower until the storm has completely passed and you are certain your home is safe.
J&K Roofing is certified and experienced in all types of metal roofing, and we partner with only the highest quality vendors. If you are in the Denver Metro, Front Range, Colorado Springs, or Northern Colorado areas, contact us to get started!