Lightning Protection - Understanding Surge Protection Systems

Protecting Your House From Lightning Strikes

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Lightning discharges can generate up to 200,000 amps of electricity in less than a microsecond. Energy bolts have no pattern or reason as to where they strike. It can strike directly underneath the cloud or reach up to 18 miles away. 

Lightning strikes happen less than once in a million times, but Environment Canada (2021) estimates that lightning kills 2 to 3 people each year and injures 80 others.

Everywhere there is lightning, there are strikes. You may experience equipment and system failures in your home if this happens. The good news is that whether you live in a house or rent an apartment, you can take steps to protect your property. 

Lightning Protection - Understanding Surge Protection Systems

Lightning Strike – Facts & Overview

Electric currents, such as lightning, usually occur and stay between clouds. 

Putting that aside, have you ever wondered what thunder has to do with lightning?

When rain, ice, or snow collide within storm clouds, the imbalance between storm clouds and the ground is increased, causing lower storm clouds to be negatively charged. 

Many small ice bits collide with one another as thunderclouds move. Electrical charge builds up as a result of all these collisions. The air’s insulating capacity breaks down when opposite charges build up, resulting in a rapid discharge of electricity we call lightning.

The temperature of lightning is extremely high: a lightning strike can heat the air around it five times more than the surface of the sun. In response to this heat, the surrounding air swells and vibrates rapidly, creating the pealing thunder we hear after seeing lightning.

From the cloud to deep into the ground, lightning searches for the path of least resistance. This is where things get dangerous, as lightning can follow an array of routes inside most houses on its journey.

A typical route may include gas and water lines, power lines, wires, TV and internet lines, drains, downspouts, and metal frames around windows. In fact, everything that is conductive in a house, including metal objects, provides a path for lightning to follow. That’s why tall buildings are especially in danger of being hit.

Why Are Tall Buildings in Danger of Lightning? 

You must remember that lightning can reach the ground without conductive materials. After all, it has just flown through miles of air, which means that electrical items in the house are nothing more than a luxury it will use.

Lightning strikes can exceed 100 million Volt-Amps. The surface of any grounded object that provides a path to the earth will produce upward-facing electrical charges or ‘streamers.’ The huge downward currents created by a lightning strike travel through this channel of plasma air.

That’s why lightning strikes can cause your home to go from perfectly sound to severely damaged in just a matter of seconds. Ultimately, it wants to reach the ground but will take whatever path it pleases.

Lightning Protection - Understanding Surge Protection Systems

Structures that protrude from the surrounding structure are most likely to be hit by lightning. These are some of the most common structures that are susceptible to lightning strikes: 

  • Poles and flags
  • Fireplace chimneys
  • Towers
  • Aerated water tanks;
  • Roof construction;
  • Staircases
  • RF, TV, mobile phone, and microwave antennas.
  • Bridges.

As we mentioned before, there is enough electricity in a single bolt of lightning to create five times more heat than the surface of the sun. The construction of skyscrapers at such high altitudes and with such high cost makes no sense if they are constantly damaged by lightning and residents are at risk of being killed.

So how can the Empire State Building and other buildings withstand hundreds of hits a year without significant damage?

Thankfully, most buildings’ electrical systems are protected by protective measures like lightning rods, conductors, and whole surge protectors to reduce the likelihood of lightning striking them.

What to Do After Lightning Strikes Your Home

Home walls and loft spaces can catch fire when struck by lightning. Your first call should be to the fire department if your house gets hit by a direct lightning strike during a lightning storm.

When you have made your initial assessment for roof damage and fire, be sure to check the following elements to check the extent of the damage:

  • Make sure the circuit breakers, outlets, and light switches are working.
  • Make sure the wiring in the home is not damaged by using a resistance tester.
  • Check whether landline telephones are still working.
  • Make sure there are no leaks in your water supply lines by testing the pressure in them.
  • Visually inspect each plumbing line for leaks.

You can learn more about what you can do after reading the Lightning Facts: What You Should Do During a Lightning Strike blog post.

Protecting the Interior & Exterior Electronic System

If your house is connected to an electrical outlet, lightning can damage electronic equipment, telephones, and other electrical appliances. Unplugging your devices when you hear thunder is the easiest way to protect them, but we have discussed how that could be a challenge for some further below. 

Some large appliances, such as washers, dryers, and stoves, are difficult to unplug before a storm. It is best to avoid using plugged-in appliances during times of severe weather.

Also, avoid using the phone. The National Weather Service reports that 4 to 5 percent of those struck by lightning were talking on wired telephones at the time.

If you’re out during a thunderstorm, you can reduce the chances of being struck by lightning by taking appropriate action early on. The first thing you should do is to seek shelter immediately in an enclosed area as soon as you hear thunder. 

Among the safest places to hide are homes, workplaces, malls, and cars with their windows rolled up. If you can’t find a place like that nearby, you should crouch or get low to the ground to minimize your chances of being struck. However, remember that you are at risk as long as you’re outside.

The National Fire Protection Association recommends that if a lightning storm is at least ten miles away, stay away from plumbing and avoid washing hands, doing laundry, washing the dishes, or showering.

Experts recommend that you don’t gather in groups whenever there’s a thunderstorm roaring in the sky. This might sound rather pessimistic, but if nearby lightning strikes the ground, this will reduce the number of injuries.

Lightning Protection Measures

You can take a few safety measures to prevent problems and save money in the long run. You may not even realize your house has been struck if you have lightning protection, but without it, you could end up with a hefty repair bill that is not covered by insurance.

The Lightning Protection Institute states that lightning protection systems use copper and aluminum, which are extremely conductive, in order to create a low-resistance path that safely grounds lightning’s electrical charge. 

Remember that lightning protection equipment and cables will need to be replaced over time, depending on their wear and tear. 

There are several types of lightning protection systems, including:

  • lightning rods
  • main conductors
  • grounds
  • bonds
  • surge protectors


Special earthing equipment and lightning conductors ensure that electrical currents are routed to the ground as quickly as possible, protecting the building from damage in the process.

Lightning conductors come in a variety of types. For example, the shape can be hollow or solid, square or round. Despite this, lightning conductors have one thing in common – their materials are all conducive.

A lightning protection system is usually made from conductive materials like copper or aluminum and is installed outside buildings or structures to prevent electrical surges. The most famous type of conductor is the lightning rod.

Lightning Rods

Lightning rods, also known as air terminals, can be used in industrial and residential buildings to redirect currents. When lightning strikes a lightning rod high up on a skyscraper, it passes through cables on the building’s roof well down to earth, where it safely dissipates. 

As a quick overview, here’s how they work: 

  1. Your home’s roof (or a building like the Times Building ) is topped with a metal rod (or several rods). 
  2. Copper wire runs from that rod to the ground, connecting it to another underground metallic rod. 
  3. This path allows the voltage to spread safely into the Earth.

Because lightning follows the path of least resistance, even rods without positive ions are efficient. A lightning rod offers much less resistance to lightning than the air, which is why metal is used in lightning rods and why lightning often strikes it.

In addition, lightning usually travels across the terra firma, so if you’re considering trees for your garden, be sure to keep them a distance away from your home. 

Surge Protectors

You will inevitably run into times when you cannot unplug your electronics in high-risk circumstances, for example, while on vacation. A transient voltage surge protector can ensure that your electronics are always protected from lightning. 

The Allstate company recommends transient voltage surge protectors for computers and other electronic devices. These electrical surge protectors limit voltage to 1.5 times the normal voltage.

These devices allow you to plug in your electrical appliances. Considering that lightning damage may cause hundreds of pounds in damage, these are very reasonable protective measures. 

Lightning surge protectors are most effective when lightning strikes indirectly (for example, powerlines and electricity grids). However, lightning surge protection may not be effective if intense lightning strikes a building directly, a far more dangerous and drastic scenario.

Whole House Lightning Surge Protection

A point-of-use surge protector cannot handle a large, lightning-caused power surge and cannot replace whole-house lightning surge protection.

Having your SPDs installed by a licensed electrician is recommended due to their connection to your house’s electrical panel. Make sure your home’s electrical grounding system is in good working order before the installation.

Make sure you also check Roar Engineering’s Power Surge Protection – 5 Causes of Electrical Surges blog to learn more about the nature of power surges.

Lightning Protection - Understanding Surge Protection Systems

Electrical Engineering Services

The failure of an electrical system can result in serious injuries (and even death), along with blazes and explosions.

It is crucial that you take safety measures to ensure your safety and the efficiency of your business. Whatever your building is, we can help protect it, whether domestic, business-related or even historic. 

Countless years of experience make our electrical experts capable of designing, implementing, upgrading, and maintaining electrical installations. Roar Engineering Electrical Engineering Services cater to both commercial and industrial clients. 

If you need any assistance with your electrical system, please don’t hesitate to give us a call. We would be pleased to discuss your needs and offer you a quote.


Storm clouds generate lightning by creating an electric field between opposite charges, which can be either contained within the cloud or reach the ground.

Lightning strikes generate extremely high electric currents (as high as 200,000A). Buildings are easily damaged by such an enormous current and can easily catch fire or cause direct damage.

Structures with lightning protection systems (LPS) reduce the chances of a structure being damaged by lighting by allowing lightning to follow and disperse a low-resistance path to the ground.

We tried explaining how you can stay safe during thunderstorms and protect your house from lightning damage in this blog. Remember not to wash dishes, bathe, or use plugged-in devices indoors during a thunderstorm. Stay away from windows as well.


When is lightning protection required?

Electrical engineers will assess your building for fire risks. A lightning protection system is required if they identify the building to be at high risk of direct lightning strikes.

Lightning bolts slamming into houses are not something anyone wants to deal with. Nevertheless, lightning will strike somewhere at any time on this planet. So, it’s best to be prepared for when the time comes.

How can you protect your house from lightning?

The dangers of lightning are as diverse as the ways in which it can present itself. Often, lightning hits cause fires, and those fires can start in hard-to-find places that are hard to detect. So, it’s best to have suitable protection devices in place to prevent your house from being damaged by lightning.

Should you put a lightning rod on your house?

Yes. A lightning rod is a home lightning protection system, but hire a qualified technician to install your lightning rod. The purpose of lightning rods is to prevent your house from being struck by lightning if it travels along a safe path. Installing one will protect your home from lightning.