In a city where the typical asking rent is nearly double the median renter household income, a project that preserves public housing, offers dozens of below-market-rate apartments and protects the environment is something to celebrate.
And celebrate they did. In his State of the City address in February 2025, the city manager of Chelsea, Massachusetts, Fidel Maltez, hailed the grand opening of the DUO apartment building as "transformational."
As the first completed project under the Commonwealth’s Public Housing Innovations Demonstration Program, DUO redeveloped the aging and deteriorated Innes Apartments — a 1950s public housing development plagued by decades of deferred maintenance — into a vibrant, inclusive community of 330 modern homes. The Massachusetts Public Housing Innovations Demonstration Program is a state-funded initiative that awards grants to local housing authorities to modernize, rehabilitate or redevelop public housing using innovative methods. DUO preserved 96 public housing units and introduced 40 middle-income and 194 market-rate apartments.
And those houses are sorely needed.
In this city just north of Boston, renters needed to make nearly $108,000 a year in 2025 to afford the typical rent, but the median tenant household income was just shy of $59,000, according to a report from the Massachusetts Institute for a New Commonwealth think tank. Based on 2023 numbers, the report deemed 72% of the asking rents in the city unaffordable, 24% of renters cost-burdened and 31% severely cost-burdened. To be considered cost-burdened, renters need to spend 30% to 49% of their income on housing.
Sustainability was also integral to DUO’s design and construction, which adopted stricter energy codes than required. The development incorporates numerous green features, including white reflective roofs to reduce heat absorption, electric vehicle charging stations, Energy Star appliances and high-performance acoustic windows.
Access to public transportation was also a component of the eco-conscious design. Chelsea is a transit-oriented community with bus access on the Silver Line, Logan International Airport and commuter rail stops. DUO also has garage parking.
"For too long, the city of Chelsea has been marginalized and ignored — leaving its residents to endure living conditions in relics of a bygone era," Mark Fallon, director of research and strategy at Hunneman and an Impact Award judge, said about the project. "This development proves that both affordability and quality can be offered to all residents of the Commonwealth no matter their ZIP code or income levels."
That kind of innovative approach to affordable housing is why the deal earned a CoStar Impact Award as judged by local real estate professionals who know the market.
About the project: The amenities in the nearly 241,000-square-foot development rival those of premier market-rate properties. They include three roof decks, two sky lounges, fitness centers and co-working spaces. A golf simulator, game room and playground provide recreational opportunities for all ages. Pet-friendly features include an indoor pup tub and outdoor dog run. At street level, 5,000 square feet of retail space is planned, with negotiations underway for a restaurant tenant that will further enliven the streetscape.
What the judges said: “DUO not only revitalizes a long‑distressed site but also elevates the broader neighborhood through robust amenities, improved mobility and economic activation, making it a model for inclusive, future‑focused urban housing,” said Stephanie Donlin, senior director of real estate for Greystar Real Estate Partners.
“What is particularly compelling is the experience offered to residents: The amenities offered within this project (roof decks, fitness centers, communal lounges, golf simulators, outdoor greenspaces) rival that of many developments within Boston proper — ensuring that no corners were cut as a reflection of the locus not being in the Seaport or the Back Bay,” Fallon said.
They made it happen: John M. Corcoran & Co. served as owner, developer and property manager alongside Joseph J. Corcoran Co. as owner and developer. Marcus Partners participated as investment partners. Cube 3 handled architecture and interior design, and Plumb House served as the construction firm.