Massachusetts owner guide
Smoke and carbon monoxide detector rules for Massachusetts rentals and condos
Massachusetts owners must install and maintain working smoke detectors and carbon monoxide alarms in every rental unit and in common areas, under the State Sanitary Code (105 CMR 410), the state fire code (527 CMR 1.00) and M.G.L. c. 148. The fire department inspects detectors whenever a residential building is sold or transferred and issues a certificate of compliance the closing needs. Tenants may not disable them, and the owner remains responsible for replacing expired units. The rules differ by building age and size, which is why we track them unit by unit.
Smoke detectors
- Required on every level, outside sleeping areas, and in the locations the fire code sets for the building's age and size. Inside the units, larger and newer buildings generally need hard-wired, interconnected alarms. Apartment buildings of six or more units built before 1975 with shared hallways also need a common-area fire alarm system under M.G.L. c. 148, s. 26C.
- In one and two family homes built before 1975, a replacement battery smoke alarm must have a sealed, non-replaceable ten-year battery and a hush feature, and must be photoelectric.
- Smoke alarms have an expiration date, usually ten years from manufacture. An expired alarm fails the sale inspection and is an owner's problem, not the tenant's.
Carbon monoxide alarms
Since 2006, M.G.L. c. 148, s. 26F1/2 requires carbon monoxide alarms in every residence with fossil-fuel burning equipment (a gas or oil boiler, furnace, water heater, stove or fireplace) or an enclosed parking area. Alarms go on every level with living space and near sleeping areas, and larger buildings have their own requirements for common areas and mechanical rooms. CO alarms also expire, typically after five to ten years.
The fire department inspection at sale
Before a residential building is sold or transferred, the local fire department inspects the smoke and CO detectors and issues the certificate (under c. 148, s. 26F) that the closing attorney needs. The inspection applies the rules for the building's age and size, so an owner who has not kept up with replacements usually finds out at the worst time. We schedule these inspections ahead of a sale and fix the list before the fire department arrives.
Owners and tenants
The owner installs and maintains the detectors and replaces expired units. Tenants must not remove or disable them, and leases we write say so. We check detectors at every turnover and every inspection, record the manufacture dates, and replace alarms before they expire rather than after.
Detector questions
Who is responsible for smoke detectors in a Massachusetts rental, the landlord or the tenant?
The owner installs and maintains them under the State Sanitary Code and the fire code. The tenant must not disable them.
Are carbon monoxide alarms required in Massachusetts apartments?
Yes, in any residence with fuel-burning equipment or an enclosed parking area, under M.G.L. c. 148, s. 26F1/2, which is nearly every building we manage.
Do I need a smoke detector certificate to sell a multi-family?
Yes. The local fire department inspects and issues the certificate of compliance required at the sale or transfer of a residential building.
What about condo associations?
The association is responsible for common-area and building systems and unit owners for their units, depending on the condo documents. We track both for the associations we manage and remind owners before expirations.
General information, not legal advice, checked in October 2026. The exact requirements depend on the building's age, size and construction; your local fire department applies them.
Official sources: Mass.gov fire safety: smoke alarm requirements · Mass.gov: M.G.L. c. 148, s. 26C quick reference
Detectors, deposits and lead paint, handled
Every building we manage is inspected on a schedule, with expirations tracked. From 6% of rent or $50 per door.