The Inspector Who™ Probably Prevented Damage From A Lightening Strike

A lightning strike to a house can blow out portions of walls and wiring, set fires, and destroy expensive electrical equipment such as computers and televisions. Even thunderstorms that drop less than an inch of rain can herald significant property damage, or even danger to inhabitants and pets.

Protection against lightening strikes is often overlooked because only about 2 percent of people actually die from lightening strikes, and damage is usually contained to one property. However, lightning can be very damaging because it can reach 50,000 degrees Fahrenheit and can carry up to a billion volts.

About 100,000 thunderstorms occur in the U.S. each year, and though it affects all parts of the country, Florida, Michigan, Pennsylvania, North Carolina, New York, Ohio, Texas, Tennessee, Georgia, and Colorado report more deaths and injuries from lightning than other areas.

Here are some very interesting financial facts offered by the insurance industry about the cost of lightning damage:

  • In 2008 there were 246,200 paid insurance claims with insured losses of $1.065 billion due to lightning strikes. The average cost per claim was $4,324. Source: Insurance Information Institute, NY, press release, 6/22/09.
  • Each year 3 to 4 percent of all insurance claims are due to lightning.

With statistics like these, it makes sense that home inspectors check to make sure that property isn’t exposed to unnecessary lightening damage. Helping to protect against lightening means they need to understand the changing technology behind these protection systems. Lightning protection needs to encompass not only the building, but also the electrical system and appliances in that building. The lightning protection system does not prevent lightning from striking; it channels the electricity through non-conducting parts of a building discharging it into the ground.

Home inspectors check structures and their lightning protection systems to ensure that the following criteria are met:

  • A whole-building surge protector is installed and connected to incoming utility lines like cable, electrical and phone, and is working properly. The incoming lines should all be bonded to the same grounding point.
  • A surge arrester is properly installed.
  • The structure’s electrical system is properly grounded.
  • All electrical circuits have arc fault circuit interrupters installed.

Home inspectors also check for signs of lightning damage that has occurred in the past. Since lightning is unpredictable there is no set rules about the damage that can occur. Damage from each lightning strike is different, some with minor damage and some with drastic damage.

The first thing the inspector who suspects lightning damage does is to determine where the strike entered the electrical system and then try to follow the paths it took through the structure. To do this the inspector must understand the normal wiring of the residence. In many cases appliances like microwave ovens, stoves, dishwashers and phones were exposed to damage even if they were not in use at the time of the lightning strike.

Inspectors also check the main service and grounding systems, and recommend replacement of all damaged equipment and also “all equipment” that was exposed during the strike. To accomplish this, the inspector must go through each room and list everything that was plugged into the receptacles, then have the homeowner operate each item.

Inspectors also check the attic, basement and surrounding property for damage. For instance, inspectors may find the following clues that lightning has damaged a property:

  • Electrical Issues – Especially an overload caused by lightening, including flickering lights, blown circuits, electrical equipment failure, and melted outlets.
  • Visual inspection of the electrical box and appliances – showing blown circuits, and carbon marks on the walls.
  • Visual signs of electrical strikes- such as ripped up ground next to metal, charred nearby trees, blown out windows, dislodged tiles, and cracked ceiling, etc.

If all the safety conditions are met and lightning has not previously damaged the home, the home inspector who diligently checked has probably prevented thousands of dollars of damage from a potential lightening strike, or repairs from a previous lightning strike.