Massachusetts building code

Codes in force in Massachusetts

Each code family with the edition and the date it took effect, as the adopting agency or statute states them.

Scope, amendments and transition rules

International Residential Code (IRC)

Scope

Statewide; applies everywhere¹

Applies to

Detached one- and two-family dwellings and townhouses up to three stories, with accessory structures⁴

Local amendments allowed?

Only through M.G.L. c. 143, § 98¹

Transition period

June 30, 2025²

International Building Code (IBC)

Scope

Statewide; applies everywhere¹

Applies to

All towns, cities, state agencies or authorities¹

Local amendments allowed?

Only through M.G.L. c. 143, § 98¹

Transition period

June 30, 2025²

International Existing Building Code (IEBC)

Scope

Statewide; applies everywhere¹

Applies to

All towns, cities, state agencies or authorities¹

Local amendments allowed?

Only through M.G.L. c. 143, § 98¹

Transition period

June 30, 2025²

Energy code, residential

Scope

Statewide; applies everywhere¹

Applies to

All towns, cities, state agencies or authorities¹

Local amendments allowed?

Only through M.G.L. c. 143, § 98¹

Transition period

June 30, 2025²

Energy code, commercial

Scope

Statewide; applies everywhere¹

Applies to

All towns, cities, state agencies or authorities¹

Local amendments allowed?

Only through M.G.L. c. 143, § 98¹

Transition period

June 30, 2025²

International Mechanical Code (IMC)

Scope

Statewide; applies everywhere¹

Applies to

All towns, cities, state agencies or authorities¹

Local amendments allowed?

Only through M.G.L. c. 143, § 98¹

Transition period

June 30, 2025²

Swimming Pool and Spa Code (ISPSC)

Scope

Statewide; applies everywhere¹

Applies to

All towns, cities, state agencies or authorities¹

Local amendments allowed?

Only through M.G.L. c. 143, § 98¹

Transition period

June 30, 2025²

State code: Stretch energy code and Specialized opt-in energy code (225 CMR 22.00 and 23.00)

Scope

Adopted locally¹

Applies to

Municipalities that adopted the Stretch or Specialized code¹

Property Maintenance Code (IPMC)

Scope

No statewide code¹

How Massachusetts adopts building codes

M.G.L. c. 143, §§ 93-100; 780 CMR

• Two volumes: residential and base. The MSBC is separated into two distinct volumes: The Residential volume regulates all one- and two-family structures and townhouses that are three stories or less, as well as their accessory structures; The Base volume regulates all structures that are not covered by the Residential regulations.³
• Posted amendments are unofficial. Please remember that the Massachusetts amendments posted on-line are unofficial versions and are meant for convenience only.²
• Statewide; applies everywhere. 780 CMR applies state-wide.¹
• Effective October 11, 2024. The tenth edition building code became first effective on October 11, 2024 with a concurrency period, during which either the ninth or tenth edition building codes could be utilized.²
• Effective June 30, 2025. This concurrency period, which was thereafter extended, ends June 30, 2025, at which time the tenth edition will be the only building code in effect.²

Applies to

All towns, cities, state agencies or authorities¹

Can local rules be stricter?

Only through M.G.L. c. 143, § 98¹

What local governments may change

M.G.L. c. 143, § 98; 780 CMR 102.2.1

• State code prevails over conflicting bylaws. 102.2.1 Municipal Bylaws or Ordinances. 780 CMR applies state-wide. When municipal bylaws and ordinances conflict with 780 CMR, 780 CMR shall govern unless the bylaws or ordinances were promulgated in accordance with M.G.L. c. 143, § 98.⁴
• Towns may license categories the state does not. 110.R5.1.3.3 Municipal Requirements. No municipality shall be prohibited from requiring a license for those individuals engaged in directly supervising persons engaged in construction, reconstruction, alteration, repair, removal or demolition in those categories of building and structures for which 780 CMR 110.R5 does not require a license.⁵

Can local rules be stricter?

Only through M.G.L. c. 143, § 98¹

Residential code in Massachusetts cities

The edition each city enforces, from the city’s own adoption page or ordinance.

For permits, exemptions and owner-builder rules, see Massachusetts building permits. To compare editions across states, see the code adoption map.