HOUSE  .  .  .  .  .  .  .  .  No. 4707

The Commonwealth of Massachusetts

________________________________________

HOUSE OF REPRESENTATIVES, November 6, 2025.

The committee on Housing, to whom was referred the petition (accompanied by bill, House, No. 1493) of David F. DeCoste and others relative to using movable tiny houses as permanent residential dwellings and accessory dwelling units, reports recommending that the accompanying bill (House, No. 4707) ought to pass.

For the committee,

RICHARD M. HAGGERTY.

        FILED ON: 10/31/2025

HOUSE  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  No. 4707

The Commonwealth of Massachusetts

_______________

In the One Hundred and Ninety-Fourth General Court
(2025-2026)

_______________

An Act allowing movable tiny houses as permanent residential dwellings and accessory dwelling units.

Be it enacted by the Senate and House of Representatives in General Court assembled, and by the authority of the same, as follows:
 

SECTION 1. Section 1A of chapter 40A of the General Laws, as amended by chapter 358 of the acts of 2020, is hereby further amended by inserting after the definition of “MBTA Community” the following definition: -

“Movable tiny house", a transportable dwelling unit built on a frame or chassis with not more than 400 square feet, excluding lofts, projections from bay windows, open decks, porches or exterior utility and storage compartments, intended for residential use on an individual house lot where single-family dwellings are allowed or as an accessory dwelling unit.

SECTION 2. Section 3 of said chapter 40A, as so appearing, is hereby amended by adding the following 5 paragraphs: - The Massachusetts Department of Transportation, registry of motor vehicles and the Secretary of the commonwealth shall establish a new category for movable tiny houses. The registry of motor vehicles shall establish a process to allow cities and towns of the Commonwealth to opt-in and apply for, issue and cancel certificates of title for movable tiny houses that meet all additional safety and equipment requirements established by the registry of motor vehicles as well as reasonable local zoning requirements including, but not limited to, septic systems established in 310 CMR 15.000, if applicable, site plan review, regulations concerning dimensional setbacks and the bulk and height of structures; provided, however, that the registration fee for said certificates of titles for movable tiny houses and manufactured movable tiny houses shall be $100.

A “movable tiny house” shall be permanently affixed to a chassis approved by the Massachusetts Department of Transportation capable of carrying the total weight of the structure and the exterior width shall not exceed any dimension prohibited by the Massachusetts Department of Transportation for movement on a public way or highway; provided further, that a “movable tiny house” shall be built in conformance with the regulations and standards of the state building code but shall not be required to have insulation in walls, floors and total ceiling assembly exceeding R13, R19 and R25 respectively.

A movable tiny house may be placed on a lot as defined in section 1A of chapter 40A of the General Laws and lived in for not less than 180 days before an on-site inspection; provided, however, that after 180 days, a movable tiny house shall be required to have an established address, energy and water source and wastewater system; provided further, that after 180 days the authority having jurisdiction of said lot shall provide for the inspection of the moveable tiny house by either the local authority having jurisdiction or a certified member of a third-party inspection agency and if the moveable tiny house meets the standards of the inspection a certificate of occupancy shall be issued.

Notwithstanding any general or special law to the contrary, a city or town may establish less restrictive rules and regulations than are permitted by this section; provided, however, that a city or town shall not establish design criteria having the effect of excluding movable tiny houses.

A city or town may incentivize hosted parking of movable tiny houses with tax abatements or other tax incentives.