Lightning and water damage

Lightning and water damage

June through August are very active weather months often including intense weather events such as wind and lightning.  During this time period in 2013, wind and lightning damage claims accounted for approximately 37 percent of all 1st party property related losses for Markel child care clients.  While wind damage is difficult to control, damage caused by lightning can be prevented.  Water damage claims were also high during this time.  Frequent causes included weather impacts, ruptured pipes and sewer back up.  Most losses caused by water damage can be prevented if precautions are taken before an event occurs.

Preventing losses from lightning

Power surges are a leading cause of claims for electrical equipment failure. The most obvious culprit is lightning, but surges come from a variety of sources. They enter buildings through phone and cable lines, satellite systems, and network cables.

All electrical equipment, including data line connections, should be plugged into surge protectors. Without them, power surges can damage all of your equipment and create unwanted downtime.  It is important to install surge protectors properly.

  • Keep cable lengths short and straight
  • Push plugs completely into sockets
  • Use surge protectors that have indicators to show the circuit is grounded and operating properly

Buying the right surge protector can save you a lot of money and headache should something happen. Here are some basic specifications to consider when looking for a reliable system that gives the most protection:

  • Outlets to accommodate all of your devices
  • A built-in fuse for added protection
  • Cable and phone outlets
  • Individual on/off switch for each device
  • A UL rating ensuring proper quality control and testing
  • An LED that indicates the unit is working
  • A high rate of total energy dissipation
  • Low clamping voltage
  • A high joule rating (the higher the number the better)
  • Fewer than 10 nanoseconds response time (recommended)
  • A warranty that insures for damages to any connected equipment

Consult with a licensed electrician to ensure that your electrical distribution system is grounded correctly.  This should include an assessment of surge protection for your air conditioning system and security systems as well.  Air conditioner losses due to lightning account for 41 percent of the claims received, and lightning damage to security and alarm panels accounted for 32 percent.

For more information on surge protection, visit

Preventing losses from water damage

To help prevent water damage, take the following precautions:

  • Check plumbing.  Look for leaking fixtures, dripping pipes, including fire sprinkler systems, clogged drains, and defective water-drainage systems.  Consider contacting a sprinkler system contractor to inspect your system for deteriorating pipes that might burst.
  • Inspect foundations and exterior walls.  Look for cracks in walls and gaps in expansion joints, the material between bricks, pipes and other building materials that absorbs movement.  Have a professional building contractor inspect significant gaps or cracks.
  • Check interior walls and ceilings.  Water stains on the ceiling or running down walls may be the sign of a much greater problem behind the drywall.  If left untreated, the ceiling or wall may collapse.
  • Inspect flashing and sealants around windows, roofs and doors.  Check sealants and caulking.  If they are brittle or there are noticeable gaps in spaces, reseal or apply new caulk to the area.
  • Check roof drainage systems and ventilations systems.  Ensure roof drains and gutters are free of debris, and that water drains away from buildings.  If the roof is in poor condition, you may need to replace it.  Make sure ventilation systems have appropriate hoods and are in good condition.  Check heating and air conditioning systems for excessive condensation of leaks in water lines.  You may need to contact a professional contractor to inspect these areas properly.
  • Raise or floodproof HVAC equipment – Floodwaters can extensively damage heating, ventilation, and cooling (HVAC) equipment. The extent of the damage depends upon the depth of flooding and how long the equipment is underwater. A good way to protect the HVAC equipment is to have a contractor move it to an upper floor or build a flood-proof wall around the equipment.
  • Direct water away from building – Make sure your yard’s grading (slope) directs water away from the building.
  • Install sewer backflow valves – Flooding in some areas can cause sewage from sanitary sewer lines to back up through drain pipes. Backflow valves are designed to block drain pipes temporarily and prevent return flow.
  • Don’t forget to protect electronic equipment from water damage too. Keep computer equipment above ground or floor level. Dust covers for computers, telephone switchboards, and other sensitive electronics provide protection should a roof leak or pipe burst; make it a practice to cover equipment before you leave for the night.
  • Never hang things from a fire suppression sprinkler heads.  Doing so might cause a malfunction in the system leading to a discharge of water that can easily deluge a room with water in a matter of seconds.

Replacing equipment or property is not easy or inexpensive—protecting it can provide you with peace of mind to help you focus on your business.

For more information about protecting your business from water damage, visit The Institute for Business & Home Safety at


Lightning and water damage
This document is intended for general information purposes only, and should not be construed as advice or opinions on any specific facts or circumstances. The content of this document is made available on an “as is” basis, without warranty of any kind. This document can’t be assumed to contain every acceptable safety and compliance procedures or that additional procedures might not be appropriate under the circumstances. Markel does not guarantee that this information is or can be relied on for compliance with any law or regulation, assurance against preventable losses, or freedom from legal liability. This publication is not intended to be legal, underwriting, or any other type of professional advice. Persons requiring advice should consult an independent adviser.  Markel does not guarantee any particular outcome and makes no commitment to update any information herein, or remove any items that are no longer accurate or complete. Furthermore, Markel does not assume any liability to any person or organization for loss or damage caused by or resulting from any reliance placed on that content.

*Markel Specialty is a business division of Markel Service, Incorporated, the underwriting  manager for the Markel affiliated insurance companies.
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