Lightning Protection at the Highest Levels: A mountaintop resort is protected from lightning strikes

by Jonathan McGaha | February 1, 2015 12:00 am

The Broadmoor Resort[1]‘s newest luxury Cloud Camp[2] property was built at the top of Cheyenne Mountain in Colorado at an altitude of 9,200 feet. Project planners recognized that the location left the property particularly vulnerable to damage from lightning strikes. To address this risk all of the structures on the site were equipped with lightning protection systems during their construction. This included the 8,000-square-foot main lodge and 11 adjacent guest cabins. The structures feature timber-and-stone construction in keeping with the style of grand western lodges. Each structure is topped off with pre-aged, corrugated metal roofing to complete the required historic look.

Mr. Lightning[3], a UL Listed, LPI Certified lightning protection design and installation firm based in Colorado Springs, Colo., was contracted to provide the engineering and labor to install the systems. Winsted, Conn.-based East Coast Lightning Equipment Inc.[4], a full-service manufacturer of UL-listed lightning protection system components, provided the specialty materials required for the project. Upon completion, the systems met all nationally recognized standards for lightning protection. Mr. Lightning routed the lightning protection system making it inconspicuous to the untrained eye. This common practice allows the system to remain both unobtrusive and relatively maintenance free.

Lightning strikes and the associated destruction they cause are a common weather dilemma across the United States. Each year, lightning strikes cause more than $1 billion in property damage in the U.S., according to the Insurance Information Institute[5]. The National Oceanic and Atmospheric Association[6] (NOAA) cites lightning as responsible for more property damage nationally than tornadoes and hurricanes combined. In spite of these dramatic statistics demonstrating the significant safety and economic concerns associated with lightning, there is good news. Unlike hurricanes and tornadoes, lightning is a force of nature for which affordable and reliable protection is readily available.

Changes in architectural design trends, increased use of conductive building components like copper flashing, metal roof systems and framing, and the integration of sensitive electronic components into critical building systems have greatly increased the safety and economic risks from lightning. Every structure should have a lightning protection system installed to protect the building, its contents and occupants from damage caused by lightning strikes.

A properly installed lightning protection system performs a simple, yet invaluable task. The system provides a specified path on which lightning can travel. When a structure is equipped with a lightning protection system, the lightning strike is directed safely into the ground, leaving the structure, personnel and building systems unharmed.

While the concept behind lightning protection is relatively simple, the requirements for proper installation are specific and often complex. The single best way to ensure proper system design and installation is to specify compliance with the nationally recognized standards for lightning protection maintained by National Fire Protection Association[7] (NFPA780), Underwriters Laboratories[8] (UL96A) and Lightning Protection Institute[9] (LPI175). Strict compliance with these requirements is essential to proper system performance. As is true with any safety system, ensuring correct installation the first time is a must, since waiting for nature to send down a bolt of lightning to test the system can have catastrophic results.

A lightning protection system that complies with national standards must include all of the following elements:

• A network of rooftop air terminals (lightning rods)
• A network of ground terminations
• A network of conductors interconnecting the air terminals and grounds
• Interconnections with metallic bodies
• Surge protection devices on all incoming power and communication lines

The first three elements serve to intercept, conduct and dissipate the main lightning discharge. The fourth element addresses the secondary effects of a lightning strike by limiting the dangers of lightning side-flashing or arcing within the structure. The last element protects power lines and connected equipment from lightning current travelling on utility lines. Each of these elements is essential to proper system performance. Failure to make proper provisions for any of these five elements can result in inadequate protection, leaving the building, building systems and occupants vulnerable to lightning’s dangerous effects.

It should be recognized that electrical system fittings and lightning protection system components are not interchangeable. Material requirements established by UL and NFPA take into account the extremely large currents that a lightning protection system is expected to carry. In addition to ensuring that the required specialty materials are used in a lightning protection system, it is equally important to make certain that all work is performed by a contractor that specializes in lightning protection.

Lightning protection expertise is typically not within the scope of knowledge held by electrical contractors, general contractors or roofers. Experienced lightning protection installers are familiar with the provisions of lightning protection standards and are skilled at designing systems that are aesthetically pleasing, safe and effective.

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Jennifer Morgan is director at East Coast Lightning Equipment Inc., Winsted, Conn., and
Lindsay Markham is technical coordinator at Mr. Lightning in Colorado Springs, Colo. For more information, visit www.ecle.biz and www.mrlightning.com.

Source URL: https://www.metalarchitecture.com/articles/lightning-protection-at-the-highest-levels/

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