Smoke & CO Detector Certificate Explained

A Smoke & CO Detector Certificate — formally a Certificate of Compliance issued under M.G.L. c. 148, §§ 26F and 26F½ — is a document your local fire department issues after inspecting a home to confirm that its smoke alarms and carbon monoxide detectors meet Massachusetts law. The seller must obtain it before closing, and it expires 60 days after the fire department signs it.

How It Works in Massachusetts

Two separate statutes govern the certificate, and both apply at every residential sale.

Smoke alarms — M.G.L. c. 148, §26F. The statute formally applies to homes built or last substantially modified before January 1, 1975. For homes permitted after that date, the building code in effect at the time of the permit governs. In practice, most purchase-and-sale agreements and most lenders require the certificate regardless of the home’s age.

Carbon monoxide alarms — M.G.L. c. 148, §26F½ and 527 CMR 1.00 §13.7.6. The CO requirement applies to every residence on sale or transfer, with no age cutoff. Homes with fossil-fuel-burning equipment (gas furnace, oil boiler, wood stove) or an attached enclosed garage have been required to have CO alarms since March 31, 2006 under Nicole’s Law.

The inspection. The seller contacts the local fire department to schedule an appointment. Both inspections — smoke and CO — are typically conducted in the same visit. Fees are set by each city or town; a single-family inspection commonly runs $50–$100. After a passing inspection, the fire department issues the Certificate of Compliance. Per the official MA DFS application form (fp-007c), the certificate expires 60 days after issuance.

What the Fire Department Checks

Smoke alarms

• Required on every habitable level, including finished basements and attics.
• Required at the ceiling at the base of each stairway leading to a floor above.
• Required outside each sleeping area, within 10 feet of each bedroom door.
• Homes permitted after August 1997 also require a detector inside each bedroom.
• All new or replacement alarms must be photoelectric — ionization-only alarms do not satisfy Massachusetts code.
• Alarms must not be more than 10 years old (527 CMR 1.00 §13.10.7.1).

Carbon monoxide alarms

• Required on every habitable level, including basements.
• Must be located within 10 feet of each bedroom door.
• CO alarms must be replaced when the end-of-life signal activates or the manufacturer’s replacement date is reached (527 CMR 1.00 §13.7.6.1.7); combination smoke/CO units must not exceed 10 years from manufacture (§13.7.6.1.8).

House number visibility. M.G.L. c. 148, §59 requires the street number to be clearly visible from the street — checked at the same inspection.

Timing and Responsibility

The certificate is the seller’s responsibility. Schedule the inspection as soon as the home goes under agreement — many fire departments inspect only a few days per week and slots fill quickly. If the home fails — most commonly due to an expired alarm, wrong alarm type, or a missing detector — the seller corrects the deficiencies and schedules a re-inspection, which typically carries an additional fee. The 60-day clock starts on the date of the passing inspection.

FAQ

Does every Massachusetts home sale require this certificate?

Effectively yes. The smoke-alarm statute (§26F) formally applies to homes built before 1975, but industry practice and most purchase-and-sale agreements require the certificate for all residential sales. The CO statute (§26F½) applies to every residence regardless of age.

How long is the certificate valid?

The certificate expires 60 days after the fire department issues it, per the official MA DFS compliance form (fp-007c) under M.G.L. c. 148, §§ 26F and 26F½. If closing is delayed beyond that window, the seller must obtain a new certificate.

What happens if the home fails the inspection?

The fire department notes the deficiencies — typically an expired alarm, wrong technology, or missing detector — and the seller corrects them before scheduling a re-inspection. Most towns charge an additional fee. The 60-day period begins on the date of the passing inspection, not the first attempt.

Can the buyer and seller waive the certificate requirement?

In ordinary circumstances, no — the certificate is required by statute and cannot be waived by private agreement. A COVID-19 emergency deferral order allowed a limited written-agreement exception, but that order was rescinded in July 2020 and normal requirements are fully in effect.