Lightning advice for churches

11 November 2020

It is common knowledge that tall buildings attract lightning and for centuries, the spires of churches have dominated the skylines making them particularly vulnerable to lightning strikes.

Lightning bolt

What happens when lightning strikes?

A single bolt of lightning can contain up to one billion volts of electricity. This can cause considerable structural damage if the bolt strikes a building.
 
The strike can cause an electrical surge and can trigger malfunctions, shutdowns and burn out the wiring. Telephones, computers, electric organs and alarm systems are all at risk.
 
Damage caused by lightning comes in two main forms:
 
  • Structural damage to the fabric of the church
    This is usually minor but can result in fires or falling masonry. 
  • Electrics
    Indirect damage to electrical systems and equipment following an electrical surge.

How can you prevent lightning damage?

Of course, there is no way to predict or prevent lightning strikes. The traditional defence for most churches has been a lightning conductor – a single Franklin rod (named because it was invented by the Benjamin Franklin) leading from the top of the spire or tower, to an earth stake buried in the ground. 
 
A modern approach to lightning protection is known as a Faraday Cage system, comprising a mesh of conductors laid at intervals over the roof and down the walls of the church, and connected to the ground by earth electrodes.

Does insurance cover lightning strikes?

Ecclesiastical church insurance does provide cover for damage caused by lightning strikes. Our risk management team offer the following advice to churches:
 
  • A lightning conductor is not a condition of cover but Ecclesiastical does advise having one fitted if the risk assessment indicates one is required.
  • Lightning conductor testing should be carried out every two-and-a-half years. 
  • Older lightning protection systems do not have to be upgraded unless the upgrade has been identified during one of Ecclesiastical’s risk assessments of the church.
  • Installing surge protection equipment can prevent damaging electrical power surges.
  • Any work on a church’s lightning protection system should be conducted by a competent specialist firm of lightning engineers.

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