BOSTON — Gov. Maura Healey signed the Affordable Homes Act to support the production, preservation, and rehabilitation of more than 65,000 homes statewide over the next five years Tuesday morning. 

The Affordable Homes Act is the largest housing bond bill in the Commonwealth’s history, containing more than triple the spending authorizations of the last housing bill, which was passed in 2018.

“The Affordable Homes Act creates homes for every kind of household, at every stage of life, and unlocks the potential in our neighborhoods. Today we are taking an unprecedented step forward in building a stronger Massachusetts where everyone can afford to live,” Healey said. “What the Affordable Homes Act represents is our ability to come together and address our toughest challenges. I am deeply grateful to our partners in the legislature for their leadership and look forward to the work ahead in implementing this law and making affordable homes a reality for every resident of our state.”

The legislation authorized $5.16 billion in spending throughout the next five years, along with 49 policy initiatives to counter rising housing costs that are a result of high demand and limited supply. 

Sections of the act allow accessory dwelling units (ADUs) by law, invest $2 billion to modernize the state’s public-housing system, boost programs that support first-time homebuyers and homeownership, provide incentives to build more housing for low- to moderate-income residents, support the conversion of vacant commercial space to housing, and support sustainable and green housing initiatives.

“Housing plays a critical role in supporting our local economies and this bill will make a meaningful difference in helping Massachusetts residents to live, work, and stay here in the state that they love,” Lt. Gov. Kim Driscoll said. “We went big with the Affordable Homes Act, and it received incredible support from members of the legislature, advocates, employers, business leaders, and health-care professionals. Together we understand the importance of investing in housing in order to remain a competitive state.”

Lynn Mayor Jared Nicholson said that the AHA will deliver crucial assistance that will help Lynn’s efforts to respond to the housing crisis. 

Nicholson said he is grateful to the Healey-Driscoll administration and the legislature for passing the act.

“Housing is one of the top issues facing the city and we are appreciative to see increased advocacy and involvement at the state level to provide local communities with transformational investments,” Nicholson said.

Charles Gaeta, the executive director of the Lynn Housing Authority and Neighborhood Development, said it was an honor to be there when the act was signed.

“I am grateful, as are our Board of Commissioners, with this legislation by the Healey-Driscoll administration for this massive bill, which includes $2.5 billion in bond authorization for state public housing, doubling of the Affordable Housing Trust Fund, the Housing Innovations Fund, and the Housing Stabilization Fund, among additional funding to increase the creation of all types of housing,” Gaeta said.

He added that the act’s new $10 million Homeownership Production Tax Credit will be an essential tool that will allow first-time buyers to become homeowners.

Gaeta said the signing of the AHA marked a great day for Lynn and the Commonwealth as a whole, and thanked the city’s legislative delegation for “understanding the growing needs for both preserving and upgrading our present housing” and providing the required financial tools to create more housing.

State Sen. Brendan Crighton said that Massachusetts is facing a housing crisis, with some of the most expensive rents and homeownership costs in the country. He said the legislature and the Healey-Driscoll administration worked hard to put as many tools in place as possible to create more housing in the state.

Crighton said that the Commonwealth needs to make sure housing costs come down as quickly as possible in order for Massachusetts to become an affordable place for families to live.

“I think a lot of it has to do with housing production, so I was proud to sponsor a bill to allow for more ADUs to be created, and was very pleased that was part of the bill,” Crighton said.

The act will allow ADUs that are less than 900 square feet on single-family lots. They can be attached to or detached from a single-family home and often take shape as a basement or attic conversion, a backyard cottage, or a bump-out addition.

The new policy replaces a variety of zoning regulations across the state with a single law, allowing homeowners on single-family lots to add small units without the need for a special permit or variance, unless they seek to add more than one ADU. 

Construction of ADUs will still be subject to local building codes. The Healey-Driscoll administration estimated that between 8,000 and 10,000 ADUs will be built across the state over the next five years due to the law’s passage

The act also authorized a record $2 billion for the repair, rehabilitation, and modernization of the state’s public-housing portfolio. Massachusetts has the largest public-housing portfolio in the U.S., with more than 43,000 units.

“Public housing is a vital piece of our housing portfolio here in Massachusetts,” Deputy Secretary of Housing and Livable Communities Jennifer Maddox said. “It provides access to affordable housing for thousands of residents while also serving as one of our best defenses against homelessness. But for too long it has suffered from underinvestment. With the passage of this bill, we say to those residents, you deserve to live with dignity in a community you can be proud of.”

The bill also created additional opportunities to develop vacant or underutilized commercial space into housing with the creation of the Commercial Property Conversion program and the Commercial Property Conversion Tax Credit.