Reimagined Mills

When the Essex Company Machine Shop was constructed in the late 1840s, it represented the height of innovation and progress. It was not only one of the first industrial buildings erected in what would be become Lawrence, Massachusetts, but was an engine and symbol of the Industrial Revolution, harnessing electricity generated by the Merrimack River and propelling Lawrence into a global powerhouse of industry. 

Now, after sitting nearly vacant for years, Essex Company Machine Shop is once again at the forefront of innovation and an electric-powered future thanks to Stone Mill Lofts, which turned the almost 200-year-old mill building into an energy-efficient, all-electric, affordable apartment community.

“Even in the 1850s, they were thinking about sustainable energy,” says Scott Maenpaa, who worked on the Stone Mill Lofts as its lead designer and project manager for the Chelsea, Massachusetts-based firm, The Architectural Team. “It’s great to be able to preserve that history.”

The $39.2 million adaptive reuse project was an ambitious one, with its developer, Boston-based WinnDevelopment, aiming to combine energy efficiency with comfortable, modern living and careful historic preservation. Since the project would be receiving state and federal historic tax credits, the team also worked closely with the National Park Service to meet its preservation goals.

First came ensuring that the exterior of the building, which is a local landmark, retained its original look and character. 

“We wanted the building to look almost as it looked when it was first constructed. We didn’t want to make it perfect,” Maenpaa says. “We wanted to bring out the natural beauty in it without having to add too many things.” 

The building’s signature granite fieldstone exterior was in great shape, requiring only gentle cleaning that brought out the stone’s natural pinkish-ochre hue. The team also replaced the historic slate roofing with new tiles from a quarry in Vermont that matched the original and restored more than 400 windows, retaining their look while making them more energy efficient.

Inside, the team needed to strike a thoughtful balance between energy efficiency, livability, and preservation. For instance, the desire to retain some of the exposed stone walls posed a challenge when it came to properly insulating the building, so the team made a clever compromise. Since the rear of the building is backfilled and below grade, the ground on that side offered some natural insulation. Putting the building’s amenity space in the back allowed for exposed stone walls in those areas and insulated the walls in the resident units. Polished slate floors, elevated ceilings with original wood beams, shiplap, and historic wood trim add to the building’s industrial aesthetic.

Another touch that Maenpaa calls his “favorite moment in the building” is a window cut into the lobby’s stone wall that reveals 1840s-era pipes that once powered electricity-generating turbines. 

“You’re looking back at what the height of technology was when the mill was constructed,” he says. “It gives you that connection to the past, which is what we’re trying to do when we do these adaptive reuse projects.” 

After several years of construction, Stone Mill Lofts started welcoming residents in September 2024. The 149,220-square-foot building has now been transformed into 86 mixed-income rental apartments, including just 17 market-rate units.

“That’s the great thing about working with Winn,” Maenpaa says. “They’re an affordable housing developer and manager, first and foremost. It’s near and dear to them. They feel like everyone deserves a place to live.”

In addition to the one-, two-, and three-bedroom apartments, the building offers a range of amenities, including a shared lounge with a catering kitchen and billiard table; work-from-home spaces; a children’s playroom; a fitness center; laundry on every floor; an outdoor terrace with a seating area; and landscaped outdoor areas. The building is also completely handicap accessible and has designated handicap units, Maenpaa says.

Its sustainability features are impressive as well, with a performance that’s competitive with passive house development. It’s also completely free of fossil fuels; uses ultra-efficient heat pumps for heating, cooling, and hot water; and is projected to use 46% less energy and emit 33% fewer greenhouse gases than a typical gas-powered multifamily structure, according to The Architectural Team. 

The project is a testament to the city of Lawrence, its history, and its resilience, too. WinnDevelopment received $2.8 million from a rebuilding fund established after the 2018 Columbia Gas explosion caused widespread destruction in the region. Other funding came from sources like MassHousing, an independent, semi-public agency that funds affordable housing in Massachusetts; the Massachusetts Executive Office of Housing & Livable Communities; and from the city itself. 

Maenpaa says adaptive reuse projects like Stone Mill Lofts show the skill, craftsmanship, and ingenuity of the past.

“I think it’s just a nod to the tradespeople and the contractors, the people that built these buildings back in the day that they’re still standing and able to give us a palette to bring them into the 21st century and give them new life and a new a new identity within a changing world,” he says. TB