SECTION 1. Section 6 of chapter 44B is hereby amended by inserting after the word “purpose”, in line X, the following words:- “; provided, however, that funds for open space or historic preservation that have not been expended for not less than three consecutive fiscal years may be transferred by the chief executive authority of the municipality for  community housing, waste water infrastructure or water infrastructure by a majority vote of the legislative body”

SECTION 2. Section 1A of chapter 40, as appearing in the 2016 Official Edition, is hereby amended by adding the following definition:-

“Tiny house”, a detached structure containing a dwelling unit with no more than 600 square feet, excluding the area of any floor level located above the main floor, intended for year round occupancy that meets the requirements of chapter 143, and may include single-room structures, and which is built on either a permanent foundation or on a chassis that is suitable for registration for transport on public highways of the state.

SECTION 3. Section 3 of chapter 40A, as appearing in the 2016 Official Edition, is hereby amended by adding the following paragraph:-

“A municipality that permits accessory dwelling units pursuant to this section shall permit a tiny house as a detached accessory dwelling unit; provided, however, that such land or structures may be subject to reasonable regulations concerning dimensional setbacks, screening and the bulk and height of structures; provided, however, that a tiny house used for habitation shall be connected to a public water system or a private well, and to a public sewer system or a subsurface wastewater disposal system that has been approved by the Massachusetts department of environmental protection. A zoning ordinance or by-law may require that the principal dwelling or the accessory dwelling unit be continuously owner-occupied and may limit the total number of accessory dwelling units in the municipality to not less than 5 per cent of the total non-seasonal single-family housing units in the municipality.”

SECTION 4. Chapter 40, as appearing in the 2016 Official Edition, is hereby amended by inserting, after section 60B, the following section:-

60C. A city or town, by vote of its town meeting, town council or city council, with the approval of the mayor where required by law, on its own behalf or in conjunction with one or more cities or towns, may exempt from property taxation, under chapter 59, a dwelling unit that is rented on a yearly basis, and occupied year-round, for an amount not to exceed 150 per cent the fair market rent established by the United States Department of Housing and Urban Development for the metropolitan statistical area. The owner of a dwelling qualifying for exemption under this section shall submit to the municipality or its agent documentation, including but not limited to a signed lease, necessary to confirm the eligibility of the rental.

The amount of the exemption shall be determined by the municipality, but shall not exceed an amount equal to the tax otherwise owed on the property based on the assessed value of the property, including accessory dwelling units, multiplied by the square feet of the living space of all dwelling units on the property that qualify under this section, divided by the total square feet of structures on the property.

SECTION 5. Section 3 of chapter 40A of the General Laws, as appearing in the 2016 Official Edition, is hereby amended by adding the following paragraph:-

No zoning ordinance or by-law shall prohibit or require a special permit for the use of land or structures for an accessory dwelling unit located internally within a single-family dwelling or the rental thereof on a lot not less than 5,000 square feet or on a lot of sufficient area to meet the requirements of title 5 of the state environmental code established by section 13 of chapter 21A, if applicable; provided, however, that such land or structures may be subject to reasonable regulations concerning dimensional setbacks, screening and the bulk and height of structures. The zoning ordinance or by-law may require that the principal dwelling or the accessory dwelling unit be continuously owner-occupied and may limit the total number of accessory dwelling units in the municipality to not less than 5 per cent of the total non-seasonal single-family housing units in the municipality. Not more than 1 additional parking space shall be required for an accessory dwelling unit; provided, however, that, if parking is required for the principal dwelling, that parking shall be retained or replaced. Exterior alterations of the principal dwelling to allow separate primary or emergency access to the accessory dwelling unit shall be allowed without a special permit if such alterations are within applicable dimensional setback requirements. Nothing in this paragraph shall authorize an accessory dwelling unit to violate or avoid compliance with the building, fire, health or sanitary codes, historic or wetlands laws, ordinances or by-laws or title 5 of the state environmental code established by said section 13 of said chapter 21A, if applicable. This section shall not limit a city or town’s authority to prohibit or restrict use of an accessory dwelling unit as a short-term rental.

SECTION 6. Chapter 23B is hereby amended by adding the following section:-

Section 31. (a) For purposes of this section:

“Affordable rental housing” means housing that serves persons with a household income of less than 120 per cent of median income for a municipality; and

“Qualified developer” means a developer that has partnered with a school district or municipality to create affordable rental housing for school district or municipal employees.

(b)The department, or any division within the department, may enter into long-term financing agreements with school districts, municipalities and qualified developers for the creation of affordable rental housing for municipal employees.

(c) Payment on a finance agreement under this section shall be deferred until the affordable rental housing that is financed is put into service and the school district or municipality begins collecting rent from the occupants of that affordable rental housing.

SECTION 7. Chapter 60 of the General Laws is hereby amended by inserting, after section 37B, the following section:-

Section 37C. A property subject to sale under section 37 of this chapter that contains three (3) or less units, the department of housing and community development, shall have a right of first refusal to acquire the tax lien at tax sale, and may assist the owner to discharge the lien or take title and acquire the property in its own name pursuant to regulations to be developed by the corporation, consistent with its purposes. The corporation shall notify the collector of its intention to exercise this right no later than 10 days before the date of sale or any adjournment of the sale. Failure of the corporation to notify the collector as provided herein shall extinguish the right of first refusal under this section.

SECTION 8. Chapter 59 of the General Laws is hereby amended by inserting after section 5N the following section:-

Section 5O. In any city or town which accepts this section, the board of selectmen of a town, or in a municipality having a town council form of government, the town council or the mayor, with the approval of the city council in a city, may establish a property tax exemption for low- or moderate-income households.

For purposes of this section: (a) a low-income shall mean a household income of less than 80 per cent of the median household income in the municipality, as established by the published income guidelines for the United States Department of Housing and Urban Development for the metropolitan statistical area; (b) a moderate-income shall mean an income between 80 per cent and 120 per cent of the median household income, as established by the published income guidelines United States Department of Housing and Urban Development for the metropolitan statistical area.

A municipality shall have the power to create local rules and procedures for implementing this section in a way that is consistent with the intent of this section.

SECTION 9. Notwithstanding any general or special law to the contrary, a special commission is hereby established for the purposes of making an investigation and study relative to the impact of the state building code, fire code, health code, and sanitary code on the availability of affordable housing in the Commonwealth and to whether or not the building code, fire code, health code, or sanitary code may be amended to promote the development of housing that is affordable for a majority of residents. The commission shall consist of: 2 members of the senate to be appointed by the president of the senate; 2 members of the house to be appointed by the speaker of the house; and 6 persons appointed by the governor, 1 of whom shall be a representative of the Home Builders and Remodeler’s Association of Massachusetts, 1 of whom shall be a representative of the Massachusetts Association of Realtors, 1 of whom shall be a representative of MassHousing, 1 of whom shall be a representative of the department of housing and community development, 1 of who shall be a representative of the Building Code Coordinating Council, 1 of whom shall be Massachusetts Association of Community Development Corporations.

All appointments shall be made not later than 30 days after the effective date of this act. Members shall not receive compensation for their services but may receive reimbursement for the reasonable expenses incurred in carrying out their responsibilities as members of the commission.

Not later than July 1, 2021, the commission shall report to the general court the result of its investigation and study and its recommendations, if any, together with drafts of legislation necessary to carry its recommendations into effect by filing the same with the clerk of the house of representatives who shall forward the same to the joint committee on housing and the joint committee on community development and small businesses.