Assembly Row – Block 9 Advances 318 Homes in Somerville

Federal Realty Investment Trust, DiMella Shaffer, and H+O Structural Engineering are advancing Block 9 at Assembly Row: an eight-story, mixed-use development at 375 Harold Cohen Way in Somerville, MA. The project will deliver 318 new homes, 12,900 square feet of retail and daycare space, and a 149-space garage, continuing Federal Realty’s transformation of the Mystic River waterfront into a connected, transit-oriented neighborhood.

Permitting Progress in Somerville

In March 2025, Federal Realty submitted a Special Permit with Site Plan Approval (SPSR-A) to the Somerville Planning Board, moving Block 9 from concept to active review. The proposal replaces a temporary surface parking lot with new mixed-income housing, supporting the city’s inclusionary zoning goals and marking one of the final steps before construction.

Community feedback from the August 2024 neighborhood meeting helped refine the design, ensuring Block 9 integrates seamlessly with Assembly Row’s streetscape and aligns with Somerville’s long-term growth vision.

Design and Structure

Fronting Harold Cohen Way and Foley Street, Block 9 brings new retail and daycare uses to the ground level, adding vitality to the pedestrian realm. Two landscaped courtyards draw daylight and air deep into the plan, enhancing livability for residents.

H+O is providing full structural design services, working closely with DiMella Shaffer to coordinate column grids, spans, and bearing walls with residential layouts. The podium integrates parking, building services, and open space. H+O’s data-driven process minimizes transfer conditions and material waste: reducing cost, simplifying construction, and advancing Federal Realty’s sustainability goals across the Assembly Row portfolio.

A Next Step in Somerville’s Urban Transformation

Following previous phases (Montaje, Miscela, and AVA Somerville), Block 9 occupies one of the final parcels in the 45-acre Assembly Row master plan. The project adds more than 380,000 square feet of housing and retail, strengthens walkability, and improves access to the MBTA Assembly Station. Its 20% affordable housing component supports Somerville’s goal for equitable, transit-oriented growth while reflecting the city’s evolving urban identity.

Looking Ahead

Federal Realty, DiMella Shaffer, and H+O Structural Engineering are shaping Assembly Row into the benchmark for sustainable, high-density development. Early structural alignment with design intent ensures cost certainty, efficient delivery, and long-term value.

In multifamily and mixed-use projects, controlling budget and risk is non-negotiable. Our data-backed structural design gives project teams the clarity and confidence to protect the pro forma and deliver with precision. Ready to elevate your next project? H+O delivers the measurable savings others miss.