Lightning Protection for Multi Family Residences
Special Risk Factors
Yes, the loud crash of a nearby lightning strike will wake all but the heaviest sleeper. But the spark from lightning does not necessarily produce an immediate, detectable blaze. Residents can drift back to sleep unaware that lightning has ignited the building and that a smoldering ember is growing into a life-threatening fire. Waking in a dark and smoke-filled room, a person may be disoriented and have difficulty escaping without injury or death.
Residents can also be exposed to electric shock and injury from structural damage to a building. Personal property can be damaged by lightning, and powerful lightning surges can fry electronic devices and appliances.
Property owners can suffer harm to their real property, including damage to or total destruction to buildings, and the loss of income during repairs or reconstruction. Property insurance does not provide full protection against all the expenses an owner may occur.
Note that multi-family buildings, also known as multi-unit buildings, are generally at increased risk of lightning strikes, compared to single-family residences. This is because their larger roof area enlarges the “strike zone” for lightning. For further information about lightning risk factors, click here:
Design and Installation Considerations
Lightning protection systems require a whole-building approach in accordance with nationally-recognized standards, including LPI 175, NFPA 780, and UL 96A.
The standards require multiple conductive paths to safely carry intense lightning surges between the sky and ground. This includes strategically located air terminals (lightning rods) at high points and on the roof, ground electrodes, and a network of heavy-duty lightning conductors to safely conduct current between them.
To equalize electrical potential, the lightning protection system must also be connected (bonded) to metallic building systems such as plumbing and HVAC as well as to existing grounds for the building’s electrical and other systems.
To complete the system, surge protection devices must be added to telephone, power, and other services entering the building, to provide protection from current traveling on those lines and entering the structure.
During building construction, conductor cables will be concealed inside attics and within walls. If lightning protection is being retrofitted to an existing building, it may be most economical for some conductors to be exposed on the roof or exterior walls. These cables can be aligned with the natural edges and architectural lines of the building and will not detract from its appearance. Rooftop air terminals are slender and inconspicuous when seen from the ground; alternatively, decorative elements like spires or ornamental metal fabrications can be used as strike termination devices to add stylistic accents.
Design and installation should be performed by individuals certified by the Lightning Protection Institute. For added assurance, installations should be certified by the LPI-Inspection Program to assure systems comply with nationally recognized standards and function as required. To make sure your lightning protection system remains in working order, have it inspected by a qualified lightning protection specialist every two to five years.
Does your building require lightning protection?
Multi-Family Apartment BuildingRooftop Terrace | Massachusetts 01 / 04
Rooftop terraces have become a popular amenity of multi-family buildings. The lightning protection system on the roof can be designed so that components do not interfere with the enjoyment of tenants and their guests. (Installation by Boston Lightning Rod Co.)More About Lightning Protection
Dormitory Lightning ProtectionNorth Court Dormitories | Richmond, VA 02 / 04
A lightning protection system was installed during the renovation of the historic North Court dormitories at Richmond University. (Installation by Loehr Lightning Protection Co.)More About Lightning Protection
Senior Living Facility Lightning ProtectionSenior Living Facility 03 / 04
The residents of senior living facilities, like this one, could have difficulty evacuating in the event of a fire. The lightning protection system shown being installed provides the occupants with added safety and security. (Installation by Mr. Lightning.)More About Lightning Protection
Military Housing Lightning ProtectionGrissom Air Force Base | Indiana 04 / 04
Military housing at Grissom Air Force Base has a vital defense against severe weather. (Installation by Guardian Lightning Protection)More About Lightning Protection
“Lightning and Fire Increases at Apartments: Who’s counting the strikes” Lightning Protection Institute, October 32, 2018
“Lightning Protection Systems on Rooftop Terraces,”
Building Enclosure, Winter 2020