Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 121A, § 13

Any such corporation may apply to the housing board for leave to change the type and character of the buildings on a project. The housing board may approve such application, unless in its opinion the proposed change is a fundamental one, in which case the provisions of section five, so far as apt, shall apply to an application for such change. The housing board shall in such case transmit the application to the mayor of the city or the selectmen of the town in which the project is located, and the provisions of section six shall be applicable to their actions thereon. The housing board, if it receives a certificate evidencing the approval of the application by the mayor or the selectmen, and if it finds that the proposed change will be in the interest of the health, safety or general welfare of the city or town and that the proposed use is authorized by section three, may approve such application, and the corporation may act in accordance with such approval.