Massachusetts launches ADU design challenge, $10M capital assistance and new construction loans to boost housing

Governor Jesse Healy announced a three-part push to expand accessory dwelling units in Massachusetts on a visit to Lexington, unveiling a statewide ADU design challenge, a $10 million capital assistance plan through the Mass Housing Partnership and a new MassHousing construction loan program aimed at moderate- and lower-income homeowners.

The design challenge will invite designers, architects and other professionals to submit replicable, high-quality ADU prototypes that the state will post online for free. "Today, we're announcing an ADU design challenge," Governor Healy said, adding that the administration will make winning and submitted plans available so homeowners can download ready-made designs.

The design challenge sponsors committed $60,000 in prize money, Secretary Ed Augustus said. "The first place award winner will receive 20,000, second place 15,000, third place 10,000, and exceptional submissions will receive 3,000 each," Augustus said, and noted categories including compact, standard, sustainable and accessible ADUs. Submissions open next Monday and will be judged by a panel of design professionals; the secretary said designers will have until February to submit (exact date not specified) and winners will be announced in late April.

To help move projects from plan to permitting, the administration is establishing a $10,000,000 capital assistance initiative through the Mass Housing Partnership to offer technical assistance and incentives to homeowners. "This program is designed to demystify that process, make it easy, make it accessible for everyone to evaluate whether this option makes sense for them and their families," Secretary Augustus said.

On financing, the administration said MassHousing will introduce affordable ADU construction financing for moderate- and lower-income homeowners beginning in 2026. Augustus specified loan limits later in his remarks: "Loans up to $250,000 will be available for detached ADUs and up to a $150,000 for attached ADUs," and said MassHousing would announce more details in January and open applications in March.

Local hosts Mark and Linda Adler, whose property was used to showcase an ADU, described a modular installation approach that took about four months from start to finish. "It's been a real plus for us," Mark Adler said, noting neighbors were supportive and the unit allows closer family support while preserving privacy. Linda Adler added, "It's really been perfect," and described the unit's two bedrooms, two bathrooms and full-size kitchen.

The administration framed the package as part of a broader effort that includes the Affordable Homes Act, which Governor Healy said made ADUs allowable by right and led to more than 1,000 ADU applications in the first six months after the law changed. Officials encouraged homeowners and designers to visit mass.gov/aduchallenge for details and to access plans.

The next steps officials described are the January announcement of further program details and a March opening of applications for financing; the design challenge timeline and prize awards were specified during the announcement.