In With The New: Renovations Present Fire Alarm System Challenges


As we all know, building renovations can take many forms. In each case, the building owner will inevitably need to upgrade or replace the fire alarm system. As a professional contractor, you must know and understand the jurisdiction’s building code, fire code and NFPA 72 2016 (National Fire Alarm and Signaling Code) requirements that apply to any type of renovation.


The first step in any renovation scenario involves auditing the existing fire alarm system. Inventory the equipment and the wiring to all devices and notification appliances. This audit will help confirm whether the existing fire alarm system meets the current code requirements enforced by the authority having jurisdiction (AHJ) for the building’s location.


The audit uncovers the upgrades and changes that can be incorporated into the building structure during renovation. It may also disclose that the existing system has become obsolete or that replacement parts will be too difficult to obtain.


The audit may reveal that the original installation used the incorrect cable, making the wiring classification not compliant with the current jurisdictional requirements. You may even discover the initial fire alarm system installation never complied with the code at the time of installation.


Before you plan any system upgrades, determine if the local fire marshal or fire-prevention officer knows of any issues related to the existing system—for example, whether it has generated regular false alarms. In addition, consult the building owner to determine fire protection goals and objectives. Seek advice from every stakeholder with an interest in the facility’s protection, including the fire insurance provider and representatives of the occupants.


With all of this information at hand following the audit and the consultation with the AHJ, you can develop a comprehensive plan to upgrade or replace the fire alarm system.


You will likely need to perform a complete test of the existing system as part of the audit. This becomes particularly important when the owner intends to upgrade appliances in the renovation area only. In anything less than a complete system upgrade, it should be obvious that adding equipment without knowing if the existing system performs as required can be a costly mistake. Even if you only added a few devices or notification appliances, you are now responsible for the entire system’s future operation. Put another way, the last person to “touch” the fire alarm system essentially “owns” it.


Section 23.6.3.4 of NFPA 72 requires a responsible party—normally the designer or contractor—to generate a change-control plan for all system configuration upgrades and system updates. The plan determines the policy and change procedure and ensures all system documentation is correspondingly updated.


As stated in Annex A-23.6.1.5: “Designers providing documents for upgrades to an existing building where the control units and all fire alarm system devices are being replaced but some portion of the existing circuits are being reused might, because of constructability reasons, opt for combining zones and the associated risk of the loss of those devices due to a single SLC short or open. The intent of 23.6.1.5 is not to impose an unnecessary burden on building owners with existing systems undergoing renovations, upgrades, or replacements. In these scenarios as well as others, the designer would be required to provide a documented, performance-based design approach to justify why the loss of more than one zone is acceptable. Documentation must be composed in accordance with 23.6.2.2 and be submitted in accordance with 7.3.7.4.”


In other words, treat the upgrade as a total system design. By adding or subtracting from an existing system, you change the system’s operational characteristics. Unless you carefully consider appropriate power supply improvements, you may also add to the system’s electrical load and cause a failure during an alarm. This neccessitates looking at the existing load on the system and how changes or upgrades affect voltage drops and notification appliance limitations on each circuit. Also, the system may control fire safety functions, such as shutting down air handlers or unlocking doors. These features must continue to function as intended.


Finally, any system changes must include a planned impairment process. This will control how the changes are managed, while notifying occupants that you have impaired the system’s normal operation and how you will notify the occupants should a fire or other supervisory initiation take place while it remains inoperable. In some cases, you may find that stakeholders require the existing system to be fully operational during the time it takes to install the new upgrades or new system.

About the Author

Wayne D. Moore

Fire/Life Safety Columnist

Wayne D. Moore, a licensed fire protection engineer, frequent speaker, writer and expert in the life safety field, has been a principal member and chair of NFPA 72, Chapter 24, as well as a former principal member of NFPA 909 and NFPA 914. He is the...

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