For one and two-family houses of any size: A person with a MA construction supervisor license (CSL) is required to provide construction oversight, with few exceptions. For most work on existing one-to-four family owner-occupied dwellings, a contractor must also register with the Office of Consumer Affairs home improvement program. For buildings less than 35,000 cu ft: A person with a MA construction supervisor license (CSL) is required to provide construction oversight including for manufactured buildings. For other buildings greater than 35,000 cu ft: Construction of such larger buildings and structures, commercial and residential, must be done under the control of a registered engineer or architect or their designee and no contractor license is necessary per the building code. See Section 107.6 entitled Construction Control in the MA building code. A few municipalities may have other contractor licensing requirements. Out of state contractors: Licensing is only required as described above. Out of state contractor licenses are not recognized in MA. A few larger municipalities have additional licensing requirements - contact the local building official. The building code applies uniformly to all municipalities in MA and is enforced by the local officials with few exceptions.
