Ask the Architect

On the dangers of lightning

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Q. We’re concerned about lightning and our new house. Should we have lightning rods, and what are the dangers of different roofs, like regular shingles, slate or metal? What about solar collectors? Do they pose more attraction or danger? Also, do you know the safest place to be in the house in a bad storm? Is it safe to be in our car, and is it true that we should stay away from windows or plumbing when lightning is flashing around us? Can a person survive being struck by lightning?

A. Lightning is an electrifying topic. Did you know that at any given time there are an average of 1,800 lightning storms somewhere in the earth’s atmosphere? Some 150,000 homes are struck by lightning every year, yet you rarely hear about them. Why? Because most homes following the National Electric Code and National Plumbing Code or some derivative are properly grounded, and in the event of a lightning strike, the ¼- to 1-second strike is directed into the ground and dissipated harmlessly. Unless the wiring or grounding isn’t correctly installed, you may never even know that lightning has struck.

As for what types of roof material to use and whether one material attracts lightning more than another, studies have shown that it makes little difference. You shouldn’t avoid using metal roofing, for example, since, again, if your home is properly grounded, you may never even know about a strike. The same goes for solar collectors and cupolas. The key is proper grounding. This isn’t to say that installing a lightning rod system couldn’t hurt, but considering the grounding of an average home and the likelihood and expense, you may not want to go to such effort.

I know firsthand about being struck by lightning. While hiking the Appalachian Trail when I was 16, my two older brothers and I were at the top of a mountain when a storm rapidly blew through the valley below. It was upon us so fast that we had nowhere to go, carrying heavy backpacks. Lightning struck the tree we ran under, just a few yards away, and we felt the jolt and dizzying surge through the water we were standing in. I later learned that the pain of the jolt and the temporary loss of speech were due to our hearts stopping. Forty people a year die from lightning, and 1 out of 10 who survive are badly hurt. My brothers and I were lucky. My parents could have lost three sons in one flash.

A car is one of the two safest places you can be, other than a grounded building. The body of the car, referred to as a “Faraday cage,” dissipates the electricity, though in certain instances, a tire may blow from the heat of the charge going from an axle to the ground. Stay away from windows, plumbing fixtures or taking a shower and, to be safe, don’t touch electrical appliances.

© 2017 Monte Leeper. Readers are encouraged to send questions to yourhousedr@aol.com, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.