There are requirements and guidelines for temporary fire alarm systems for buildings under construction. Regardless of the building code enforced in a jurisdiction, a fire marshal may inform the property owner that certain fire protection measures should be in place to ensure the building under construction will not be a total loss to a fire, and more importantly, the workers in the building will be provided warning of a fire occurrence.

By the numbers

In an October 2023 NFPA report, “Fires in Structures Under Construction” author Richard Campbell found that “from 2017 to 2021, local fire departments responded to an estimated average of 4,440 fires in structures under construction per year. These fires caused an annual average of five civilian deaths, 59 civilian injuries, and $370 million in direct property damage. Only 1 percent of all the reported structure fires were in structures under construction, but these fires accounted for 3 percent of the direct property damage in structure fires.”

According to the report:

• After declining from 2006–2010, the estimated number of fires in structures under construction has increased since 2014.
• 76% of structures under construction that experienced fires were residential.
• The leading cause of fires on construction sites was cooking equipment, though these fires tended to be minor.
• Intentionally set fires comprised fewer than one in 10 fires (8%) but resulted in 45% of the direct property damage.
• Fires in structures under construction occurred most frequently in January and least frequently in October.
• The afternoon and evening were the most common times for fires. However, those that occurred between midnight and 6 a.m. contributed to just over half (51%) of the direct property damage.

The report continues, “The leading factors contributing to the ignition of fires in structures under construction included heat sources being too close to combustible materials, abandoned or discarded materials or products, and electrical failures or malfunctions. Other factors contributing to construction fires included cutting or welding too close to combustible materials, unclassified misuse of materials or products, and mechanical failures or malfunctions. Good worksite practices should include regular maintenance for the equipment. Fire safety procedures for the use of powered equipment and combustible materials should also be established.”

NFPA 241, Standard for Safeguarding Construction, Alteration, and Demolition Operations, covers the installation of fire protection systems in buildings under construction. For starters, Section 4.5.1 states that “Fires shall be immediately reported to the appropriate emergency services organization in accordance with the Fire Prevention Program” (as outlined in Section 4.2 of NFPA 241). 

If a fire detection system, sprinkler system supervision, off-site monitoring using a remote supervising station or building notification appliances are to be installed and required, they must follow the Fire Prevention Program as outlined in NFPA 241 and NFPA 72, National Fire Alarm and Signaling Code.

What can you do?

Obviously, trying to wire a fire alarm system in a building under construction presents many challenges.

There are many wireless devices available in the marketplace for installing a fire alarm system under these conditions. For example, one manufacturer has a wireless device that can be connected to any dry-contact switch, such as manual pull stations or automatic sprinkler system tamper or flow switches, and transmit their status to any fire alarm panel.

There are also wireless transmitters that can signal a remote supervising station. Using this equipment allows installers to comply with NFPA 241 and NFPA 72.

There are currently wireless devices such as manual fire alarm boxes and wireless notification appliances. About the only device that may need to be wired would be the control panel that connects wirelessly to all the devices installed as part of the system. All that said, this could be a system that you “rent” to the owner while installing the hardwired, code-compliant fire alarm system. There are a few manufacturers that will assist with the wireless systems, which were originally developed for historic buildings where installing wire would deface the property. These systems have now become useful in many commercial applications.

The better wireless equipment to use is something that has a wireless mesh system integrated with a control panel to create flexible wired/wireless intelligent fire detection. This type of system offers the flexibility to provide a temporary system while the building is under construction. 

As you finish a floor in the building with the wired installation, you can remove the redundant wireless system. Be creative, and you will continue to be the trusted advisor to the owner and develop a new profit center.

stock.adobe.com / Seventyfour / Odisdca