Direct Strike: Protecting modern buildings from 300 million volts

Shutterstock / Armand Rochas
Shutterstock / Armand Rochas
Published On
May 14, 2021

When lightning strikes a building, facility owners are either grateful for their lightning protection system, or wish they had one. That is more true today than ever—as weather gets more extreme, lightning strikes more common and buildings more sophisticated, so too must the lightning protection and grounding systems designed to protect them.

The adage that lightning doesn’t strike the same spot twice is proven wrong by Mother Nature, again and again. In fact, said Jennifer Morgan, director and secretary/treasurer of East Coast Lightning Equipment (ECLE), Winsted, Conn., some buildings sustain multiple strikes a year. For example, the Empire State Building is struck nearly two dozen times each year. At the heart of each lightning protection system (LPS) installation is the prevention of disasters—the kind that appear on the news.

“Every time a storm hits and the news reports a high-rise being hit, the LPS company knows its work is providing protection,” Morgan said.

Addressing storm risks for a century, the lightning protection industry is a highly specialized field that has grown in demand and complexity. Most of the lightning protection contractor specialists in the country provide their work as subs for electrical contractors, and some ECs are beginning to offer lightning protection as part of their grounding and electrical services.

Consider where it started—LPSs used to be installed mostly on bare, flat rooftops and high-profile buildings, and the installation was relatively straightforward. The system often had the roof to itself, with the exception of a fan or generator. Today, rooftops are used for gardens, pools, solar panels and even fitness areas, meaning lightning protection must share the real estate while also being aesthetically pleasing.

Absorbing lightning in the Windy City

HLP Systems Inc. is a lightning protection specialty contractor in Libertyville, Ill., that has seen the business evolve over the past few decades. It offers lightning protection and grounding systems, mostly in high-rise and commercial construction, and, in some cases, for renovations of buildings dating back to the early 20th century in the Chicago area, said Jeffrey Harger, HLP’s president.

The company, which started in the 1960s, is in its third generation of family management.

“The business has changed quite a bit,” Harger said, adding that the basic technology is the same, but with advancement in electronics and changing codes and standards. “The work has become more complex.”

In the past, lightning rods were installed on rooftops after construction was finished. Older buildings undergoing renovation often need to put in new lightning protection to meet current codes and standards. Historical buildings often didn’t benefit from grounding systems at the time the original lightning protection was installed. To serve new and renovated projects, HLP employs a team of lightning protection technicians through its own apprenticeship program.

“It’s a specialty trade,” Harger said, adding that roughly 95% of the company’s customers are electrical contractors.

In most cases, lightning protection specialty contractors are working around balconies and a variety of roof-level amenities.

“We work closely in early design stages with architects and engineers to help conceal the cables and lightning rods as much as possible,” Harger said, adding that this was never a concern in earlier decades. But, he said, today, “we get called by [engineers or architects] before projects even hit the street to help design the system.”

The company’s systems are being deployed in such high-profile buildings as One Chicago Square, which consists of several towers in the city’s River North neighborhood. HLP was involved in the building plans at least a year before construction began.

“With new materials and techniques, it’s a lot more about design than running wire,” Harger said.

HLP is also deploying a system at Wolf Point East apartment towers and installed the lightning protection at Trump International Hotel and Tower.

The systems are no longer confined to skyscrapers. Whether in a city or at a rural distribution center, when lightning discharges, it feels its way through the air to connect to the ground, jumping in “steps” from the sky to ground at a mind-boggling speed of 220,000 miles per hour, or 61 miles per second. It may strike the side rather than the top of a building or right next to a tall building.

Being proactive is helpful, but often lightning protection is installed after a storm, rather than before. So a project may take place on the roof of a 15-story building next to an 80-story skyscraper, for instance, Harger said. Those smaller buildings are still susceptible to lightning, despite the skyscrapers towering around them. Because a smaller building’s roof is fully visible from the upper levels of those taller buildings, aesthetics are also key.

“A lot of the time, what’s on top of these buildings is almost as important as what’s at the front door,” Harger said.

If a building is being reroofed, a certified lightning protection specialist may need to step in as the protection system is removed and then re-installed. Mistakes can be critical; for example, installing the system more than two feet from the roof edge leaves eaves unprotected.

Meeting standards

As the use and design of buildings change, understanding how to safely protect them must change as well. In addition, the advances in research on lightning physics now make it possible to predict where lightning will likely strike on a structure, find the vulnerabilities in a building and engineer the correct protection system around that information.

NFPA 780 is the standard for lightning protection installations and is updated every three years. The current edition is 2020. The document covers installation requirements for ordinary structures, special occupancies and structures that contain flammable vapors, gases or liquids. Companies that don’t follow the standards or don’t gain certification pose the risk of installing a system that’s ineffective.

The same safety standards need to be followed for the people on-site.

“We’re no different than any commercial tradesman; we have to have all the OSHA and safety training and all the same fall protection,” Harger said.

The company typically has 130 projects going at once, from northern Wisconsin to southern Illinois, Indiana and Iowa.

ECLE has served the industry as it has changed and grown as well. The company provides the hardware needed for these installations, for companies that have the right certification, Morgan said.

“We’ve seen over the years that, if a company doesn’t take the time to learn what NFPA 780 says, or go through the process with Underwriters Laboratories, they can make some mistakes,” she said.

There’s no room for errors when thunderstorms pass through.

Protecting living buildings

The advancement of electronics also makes lightning protection more imperative than it was a few decades ago. Today, ECLE’s materials are being deployed at sites such as automated warehouse and distribution facilities. These highly active buildings have no tolerance for downtime and they have gigantic roofs, requiring large material, she said. When it comes to distribution centers, for example, the buildings teem with robots, elevators and building intelligence, which could be affected by a lightning strike. HVAC systems are also more sensitive and more expensive to repair.

“The whole thing is a piece of machinery, so the lightning protection system is just understood as not being something you want to skip,” Morgan said.

Additionally, the bigger the building’s footprint, the more likely it will be hit by lightning.

iStock / Best Content Production Group
iStock / Best Content Production Group
 

Each project means multiple visits for the lightning protection provider. Even on a simple job, the lightning protection provider’s presence is required when the foundation is going into the ground, when the walls go up—often coinciding with the electrical contractor—and when the network is completed on the roof.

Morgan finds that sometimes lightning protection contractors only do the roof installation while the ECs help with the grounding and wall deployment. Meanwhile, data centers have very elaborate grounding systems, and electrical contractors often work closely with the lightning protection provider to install that grounding.

“It’s easy to sell products after a building has been struck by lightning,” Morgan said. “That’s not our preferred way to go about sales, but many people don’t think about it until they see the problem.”

Finding the ground

The Lightning Protection Institute (LPI), Libertyville, Ill., identifies key trends leading to industry growth—medical facilities and data centers that can’t afford to lose power.

“We’re an industry with generations of experience,” said Tim Harger, LPI’s executive director and program manager for the LPI Inspection Program. “Lightning protection and grounding systems are the final component systems in best-practiced, electrical construction and structure envelope design.”

While the industry still sees a lot of the traditional work with the military, schools and government, as well as high-rises, as building industry grows, the percentage of buildings that have lightning protection on them also is growing, he said.

LPI committed to elevating the quality of work in the industry by ensuring that systems are inspected and certified, LPI’s Harger said.

“There are about 120 lightning protection contractors across the country,” he said. “It’s a unique industry, it falls in the electrical arena, but you need to know what you’re doing to install the system properly.”

While some electrical contractors are providing lightning protection, more commonly it is two separate activities.

Weather has also affected the business.

“We’re seeing an increase in lightning in storms. People are realizing now there is something you can do to protect yourself, mitigate property risk and reduce downtime to your business or daily lives,” Tim Harger said.

“I see more and more electrical people creeping into the business too,” said Kelley Collins, membership and communications liaison for LPI. “In areas with really strong [lightning protection] contractors, they tend to hire that out. It would be great to have a background knowledge of electric, but when you look at lightning protection, there are certain heights to rods, materials. Those rooftop angles and dimensions change the way the rods are installed in the roof. It’s a unique process to understand how to adapt the system to the changing building. Through NFPA, the way we calculate the zone and protection used to be straight lines and angles; now 3D CAD systems are used to design the system to 3D installation.”

One trend in the post-COVID business world may be more work occurring on residential sites, typically the larger ones. Collins said that homes are becoming data centers in some cases. With the advent of mobile workers and remote work locations, these buildings need to be protected.

“We’ve seen high-rises struck multiple times in major cities,” she said. “The outcome you want to have is nothing exciting happened.”

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