What is a lightning protection system and how does it work?
The highly conductive copper and aluminum materials used in a lightning protection system provide a low resistance path to safely ground lightning’s dangerous electricity. These materials and components are UL-listed and specially manufactured for lightning protection. When a lightning protection grounding network is in place, the strike is intercepted and directed to ground without impact to the structure, occupants or contents. A lightning protection system that meets national safety Standards of NFPA 780 and UL 96, UL96A includes strike termination devices, down conductors, bonding, and surge protection. Failure to follow the Standards or use of non-listed materials or methods can result in inadequate protection.
Aren’t lightning rods a thing of the past?
Lightning protection systems are installed more today than ever before. According to U.L., lightning accounts for more than one billion dollars annually in structural damage to buildings in the U.S. This statistic doesn’t include costs due to loss of business, downtime and repairs. Since today’s homes and buildings are equipped with a variety of sensitive electronic systems, lightning protection systems serve an important purpose. Protecting occupants, structures and critical building systems is an important part of the building design phase, which is why construction planners are specifying more lightning protection today, than ever before.
Doesn’t lightning protection attract lightning?
No. This is a common misconception about lightning protection. Lightning protection systems and strike termination devices (rods) simply intercept a lightning strike and provide a safe and effective path that takes lightning’s harmful electricity to ground. Lightning will strike a location whether there is lightning protection in place or not. When a system is in place it provides a preferential low resistance path for lightning from its intercept location to a ground destination. A lightning protection system directs lightning’s harmful current to ground, instead of it traveling through a building’s plumbing or electrical system.
Is lightning protection expensive?
Lightning protection is an affordable amenity that offers protection against a leading cause of property damage. While pricing generally runs less than 1% of the value of the structure, costs for protection vary depending on the size of the structure, location, construction, roof type and grounding conditions. As a rule of thumb, lightning protection is typically less expensive than other building systems and amenities like security, plumbing, generators and specialty lighting fixtures. A LPI-certified specialist can provide helpful pricing information for your project and region.
Can I install my own lightning protection?
Lightning protection is not a do-it-yourself project. Only experienced and reputable UL-listed and LPI-certified lightning protection contractors should install lightning protection systems. Qualified specialists use UL-listed materials and ensure that methods of installation comply with nationally recognized Safety Standards of LPI, NFPA and UL.
Do trees protect a structure against lightning?
No. And unfortunately, lightning can side-flash from a tree and hit a nearby structure. In addition, lightning traveling along tree roots can enter a structure by jumping onto nearby telephone, cable and electrical lines, introducing harmful surges. Lightning can also injure a tree from a direct strike that can cause heavy limbs to split and fall onto a nearby structure. Lightning damages and kills more trees than we can account for in the U.S., so unless a tree is equipped with a lightning protection system, it can be extremely vulnerable to damage by lightning—and a nearby structure can be vulnerable, as well.
Isn’t a whole-house surge arrester enough protection?
No. Surge protection is only one element of a complete lightning protection system. Lightning is the rapid discharge of atmospheric electricity that can pack up to 200 kA of electric energy (100 million volts of power). A lightning strike to an unprotected structure can be disastrous and a single incident can cost thousands of dollars, with losses ranging from damage to expensive electronics to fires that destroy entire buildings. No surge protection device or “whole-house” arrester alone can protect a structure from a direct strike packing mega electricity. A grounding network for lightning (lightning protection system) must be implemented to provide structural protection. A complete system includes: strike termination devices, conductors, ground terminals, interconnecting bonding to minimize side-flashing AND surge protection devices for incoming power, data and communication lines to prevent harmful electrical surges. Surge protection + the grounding network = a complete lightning protection system.
Don’t grounded weather vanes or antennas provide enough protection against lightning?
No. In order for a structure to be protected from lightning, a full system that complies with Safety Standards of NFPA 780 and UL 96A needs to be installed. Installing partial lightning protection as provided by a grounded weathervane, antenna, cupola and even a church steeple can be more dangerous than providing no protection at all. A single path to ground is not adequate to conduct the current involved with a lightning discharge. Lightning is a unique form of electricity. When the lightning strikes a partial system, side-flash to other conductive components on or in a structure can occur. This side-flashing can also damage building wiring, computer systems, and electronics and result in structural damage or even fire. There is no way to provide “some” protection from lightning. A full system with all the elements (strike termination devices, conductors, bonds, grounding and surge protection) are essential for safe and effective protection.
Will my insurance company provide a discount for my home lightning protection?
Insurance companies in most states offer premium credits for security systems, fire alarms, residential sprinkler systems, permanently installed back-up generators and other protective measures for the entire perimeter of the home. Lightning protection systems are generally recognized as “protection for the entire external perimeter” and as such, are often considered for credits. Homeowners interested in securing an insurance credit or discount for their lightning protection system installation should check with their provider. Policies about lightning protection discounts vary by insurance company. Since some providers don’t have set policies regarding credits or incentives, the homeowner should contact their agent or broker for assistance in determining their eligibility for a discount.
Aren’t steel-frame buildings already safe from lightning?
While a building’s structural steel will conduct lightning, bonding, interconnection and grounding provided by a lightning protection system is needed to dissipate lightning’s harmful electricity safely to ground. Arcing, side-flashing and potential differences can occur without the continuous preferred path to ground provided by the lightning protection system. Without the presence of the system, lightning can fight its way through mechanical, electrical, communication and HVAC systems—none of which are designed to provide a safe path to ground for lightning. A complete lightning protection system is needed to interconnect structural steel and grounded systems at grade level and roof level to equalize potential and keep the lightning on a preferred path to ground.
Since my structure is already grounded, why do I need lightning protection?
The electrical ground installed by your electrician is there to protect the internal workings of the electrical system in your building to accommodate everyday electricity usage. The electrical ground is not designed to handle the mega electricity (100 million + volts of power or 200 kA of electrical energy) that a typical lightning strike can pack.
What does the lightning protection system look like? Will it detract from the aesthetics of the structure?
Entrusting your lightning protection system design and installation to a LPI-certified professional ensures a safe and effective system that won’t compromise aesthetics. In most situations, lightning protection systems are neat and inconspicuous. When properly installed, components such as strike termination devices, conductors and grounding are barely visible to the untrained eye. There are a number of design and installation measures that can be employed to make lightning protection even less noticeable. Contracting with an LPI-certified professional will ensure attention to detail is met for every structure and roof type.
Do lightning protection systems really work?
The science of lightning protection has come a long way since Ben Franklin first invented the lightning rod in 1752. While the principles behind the science of lightning protection remain the same, today’s structures and their amenities have presented several challenges that the lightning protection Standards have needed to address. The NFPA has maintained a Standard for lightning protection for over 100 years. The Standard is routinely updated and edited to incorporate improvements in technology and new scientific findings. The FAA, NASA, Dept of Energy and DoD routinely specify NFPA 780 Safety Standard-compliant lightning protection for their structures. Federal agencies rely heavily on nationally recognized specifications of LPI, NFPA and UL and consider lightning protection systems as critical in protecting our national infrastructure. Today’s lightning protection systems provide practical and tested solutions for the interconnection of grounded building systems, surge suppression, requirements for communication and data lines and their coordinated bonding. This adds up to a total package protection approach which is a lot more involved than the original lightning rod born from Ben Franklin’s genius for invention.
What are the odds of lightning striking a structure? Why do structures need lightning protection?
The earth experiences 100 lightning flashes per second and the U.S. alone has more than 40 million lightning strikes each year. Thunderstorms occur virtually everywhere and that puts just about any type of structure at risk to lightning damage. Lightning routinely strikes in low lying areas of the world, as well as in higher elevations which is why lightning is considered the weather hazard “most commonly experienced by most people in the world.”
Unlike most other weather hazards, lightning is a preventable risk which is why protection systems are part of the structural design of many homes, commercial buildings, and public facilities worldwide. In a climate where risk reduction is so important, systems are routinely specified for industrial parks, manufacturing plans, churches, schools, banking centers, hospitals, military installation, historical landmarks, emergency centers, sporting complexes, correctional facilities, corporate centers, chemical plants, oil refineries, nuclear plants, and many more structures.
Who should install lightning protection? Can’t my roofer, electrician or general contractor take care of the lightning protection?
Lightning protection is a highly specialized trade that is governed by industry safety Standards. Design and installation is typically not within the scope of expertise held by electricians, general contractors or roofers. Only trained experts, like LPI-certified contractors that specialize in lightning protection should install these systems. Design and installation is not a do-it-yourself project. LPI is your trusted resource to put you in touch with qualified lightning protection specialists who can install systems in accordance with LPI, NFPA and UL safety Standards. Strict adherence to national safety Standards is the best way to ensure safe and effective protection.
Does lightning protection prevent lightning from striking?
Nothing can prevent lightning from striking. If lightning is zeroed in on a particular object it will strike regardless of any device or mechanism on the ground. The purpose of a lightning protection system is to intercept the lightning strike and dissipate it safety into the ground. In a system, the strike termination devices (lightning rods) are placed at regular intervals on the highest and most exposed parts of a structure. The strike termination devices become the most likely point of contact for the lightning streamer attachment, as they represent the quickest path to ground. A lightning protection system doesn’t attract, repel or prevent a lightning strike; rather a system provides an efficient grounding network that provides a low-resistance path to ground for lightning’s electricity.
Are there lightning protection requirements?
While lightning protection is routinely specified, guidelines for requirements vary in different parts of the country. There are many signs that requirements for lightning protection are on the rise. Trends we are seeing in the industry include:
- Insurance companies recommending lightning protection and providing customer incentives for system installations.
- Requirements at local levels, as seen in the State of Florida requiring lighting protection on buildings such as educational facilities, hospitals, extended care homes and healthcare facilities.
- Federal agencies like the FAA, Veterans Administration, Dept of Defense, Federal Bureau of Prisons and others developing customized lightning protection standards and requirements. Requirements here, typically call for lightning protection to meet or exceed NFPA 780, with third-party inspection certification cited for all systems (as provided by UL or LPI-IP).
- Litigation stemming from large-scale lightning losses and OSHA issued citations for failure to provide adequate lightning protection has caused mounting concerns for today’s building planners. Since lightning is often seen as a preventable loss, mitigation guidelines are increasingly calling for construction planners, architects and engineers to include provisions for lightning protection or lightning protection risk assessment in their projects.
- Concerns about CSST gas piping and lightning-related losses have led to increased recommendations for lightning protection, bonding and grounding applications for homes in high-risk regions.
LPI-certified specialists stay appraised of industry requirements and can assist with guidelines specific to your region and project.
When is the best time to have the lightning protection installed?
Lightning protection can be installed for existing structures and new construction, as options are available to incorporate installation at just about any phase of construction. However, lightning protection that is specified during the planning and design phase may provide the most options for concealing components and materials. Early planning can also allow for better coordination of work with other trades. This coordination can be beneficial when making provisions for chases for interior conductor runs, ground locations and use of compatible roofing components and adhesives. LPI-certified specialists can provide design, specification, consultation and installation services to develop a plan that best fits your project needs.
Is maintenance needed for lightning protection?
Once your lightning protection system has been installed, it’s important to take measures to ensure the system remains safe and effective. Industry lightning protection safety Standards of LPI 175, NFPA 780 and UL 96A recommend periodic inspection of lightning protection systems to ensure safety, system continuity and proper maintenance. A maintenance inspection is especially important if modifications to your structure have occurred, including: renovations to roof, electrical system updates, satellite dish installations or HVAC alterations. Maintenance may also be needed if cable T.V. or telephone systems have been serviced in recent years. LPI-certified specialists can advise regarding maintenance plans and industry requirements to ensure the continued performance of your lightning protection system.
Why does the lightning protection system need to be connected to gas and water pipe systems? Doesn’t that pose a safety concern?
Common bonding connections are needed to eliminate safety concerns. Since lightning is traveling through the soil, it can be picked up on service lines in the ground, such as underground conduits, water pipes or gas lines, and feed a portion of the harmful lightning along these systems back into a structure. The lightning protection Standards (LPI 175, NFPA 780 and UL 96A) require the lightning protection system to be commonly connected to all underground piping systems that enter the structure. These include gas piping, water piping, conduits, etc. The bonding does not introduce lightning charges into your gas and water pipes, but rather routes the charges away from the pipes to bring all grounded systems to the same electrical potential as the lightning protection system ground. The gas and water piping are not substituted for the ground, rather the connection is to provide common ground potential, reducing the risk of side-flash or arcing during a lightning event.
What do I need to know about quality assurance for my installation? Why are LPI credentials important for lightning protection?
LPI-certified specialists are dedicated to ensuring that today’s lightning protection systems provide the best possible quality in both materials and installation practices for maximum safety. LPI’s testing and Certification program was created in 1971 by the industry to qualify competence in lightning protection. The program responds to the needs of government agencies, architectural and engineering firms and insurance underwriters to certify excellence in system design, installation and inspection.
Here are reasons why specifying LPI credentials for your project is important:
- LPI-certified installers must successfully pass the industry’s most comprehensive testing requirements to receive certification.
- Yearly recertification is required for Master Installers and Master Installer/Designers.
- Certification assures that national safety Standards of LPI, NFPA and UL are met.
- Certified installers and designers possess up-to-date knowledge of changes in safety standards and scientific findings in the industry.
- Certified installers and designers possess experience in a highly specialized trade to ensure competence in system design, installation, inspection and maintenance.
- Certified installers know the best methods and materials to ensure attention to quality and aesthetics.
- Certification is voluntary within the industry, which means your LPI-certified specialist holds himself/herself to a stringent standard by electing to pursue the highest level of education and excellence in lightning protection.
- Contracting with a LPI-certified specialist saves you time and money.