As of February 2, 2025, Massachusetts has legalized Accessory Dwelling Units (ADUs) by-right statewide through the Affordable Homes Act signed into law in August 2024. This law was put in place to address the housing shortage and provide more affordable housing options. ADUs are seen as flexible supplemental housing that can house family members, generate rental income, or provide aging-in-place options. They are one of the simplest, most cost-effective ways to introduce additional housing units into already established neighborhoods.

At the Boston Society for Architecture (BSA), we support the production of ADUs to increase housing options at the neighborhood scale and strengthen community resilience and diversity (Housing Advocacy Platform 24-25). Earlier this year, the BSA curated an ADU Directory to serve as a resource for homeowners and stakeholders seeking qualified architects and firms to bring ADU projects to life. The directory lists individual architects and firms with expertise in ADU design and offers contact details and project profiles to help homeowners find the right professional partner for their project. The directory was created in response to sustained demand from homeowners, cities, and others for a centralized resource to facilitate connections, reflecting a growing interest in ADUs as a practical housing strategy.

The BSA is excited to see this work expand through the Executive Office of Housing and Livable Communities' ADU Design Challenge, which brings together great design, public purpose, and real impact statewide. By creating ADU designs that are accessible, sustainable, and climate-resilient, we have a chance to lower barriers for homeowners while meaningfully expanding affordable housing options across Massachusetts.

This challenge recognizes that thoughtful design can streamline permitting, enabling lifelong housing options, and help communities grow more equitably. As Massachusetts continues to confront a shortage of affordable housing, the combination of public design resources and professional architectural connections promises a new era of thoughtful, community-driven development that we are excited to continue to advance.

The BSA highly encourages members and practitioners to participate in the ADU Design Challenge, which includes cash prizes totaling $60,000, with awards for overall winners and for designs that exemplify compact, sustainable, accessible, and innovative approaches. Winning entries and other standout submissions will be published on Mass.gov, featured in a design guidebook, and promoted statewide.

Key Dates:

• Competition launch: Dec. 15, 2025

• Submission Deadline: Feb. 27, 2026

  • DEADLINE EXTENDED: Mar. 2, 2026

• Webinar Dates: December 19, 2025 & January 15, 2026

• Jury review: March 2026

• Winners announced: April 2026