Where can an energy storage system be located in a building?

With the prevalence of energy storage systems (ESS), particularly battery energy storage systems (BESS), this question is asked by authorities having jurisdiction (AHJ) across the country.

For one-two family dwelling units, BESS are permitted for installation in detached garages/accessory structures, attached garages separated from the dwelling in accordance with International Residential Code® IRC® R302.6 (occupancy separation), and enclosed utility closets, basements, storage or utility spaces with finished or non-combustible walls. The BESS cannot be installed in habitable spaces of dwelling units including sleeping rooms, spaces opening directly into sleeping rooms and closets. If installed on the exterior of a dwelling unit, the ESS must be located at least 3 feet from doors and windows.

For commercial buildings, BESS are permitted for installation in any indoor area of the building, subject to size limitations, enclosure requirements, separation, ventilation, and fire detection and control. There are separate requirements for rooftop, exterior, and parking garage installations. For systems above 600 kWh storage capacity, a dedicated ESS building is typically required.  NFPA® 855 is another standard for installation of stationary ESS.

Learn More

• View this recorded webinar to hear a discussion between a California Fire Marshal and an advisor to a DOE national lab on energy storage system safety. Recorded webinar.
• Take a mini-course about the basics of energy storage systems.
• Download a guide to multiple codes related to ESS Guide: Energy Storage Systems: Based on the IBC®, IFC®, IRC® and NEC® hear a discussion between a California Fire Marshal and an advisor to a DOE national lab on energy storage system safety.