Fairfax County, VA Fire Regulations: Smoke Detectors (2026)

Virginia's Uniform Statewide Building Code (USBC, 13 VAC 5-63) governs smoke alarm installation in Fairfax County. New residential construction and substantial renovations require smoke alarms that are hardwired to the building's electrical system with battery backup, interconnected so all alarms sound when one activates, and installed in every sleeping room, outside each sleeping area, and on every story including basements. Alarms must meet UL 217. For existing homes, the Statewide Fire Prevention Code (SFPC) Section 1103.8 requires smoke alarms be maintained in operable condition. Since 2015, Virginia law has required 10-year sealed lithium battery alarms in many replacement scenarios — VA Code §27-97 and §27-97.1 require that any replacement alarm in existing dwellings (not interconnected/hardwired) be a 10-year sealed battery model. Carbon monoxide alarms are required in dwellings with fuel-burning appliances or attached garages under USBC. Landlords must certify working alarms at the start of each tenancy under VA Code §55.1-1227 and test them at tenant request. The Fairfax County Fire Marshal offers free smoke alarms and installation to eligible residents through the Smoke Alarm Program. Tampering with or removing alarms in rental property is a violation. Hotels, short-term rentals, and group homes have enhanced requirements.