3458 Washington St, Jamaica Plain, MA
New mixed-use development | Passive House certification | High-efficiency MEP system | Energy recovery mechanical system
This five-story, approximately 35,000 sq. ft. mixed-use building is designed in accordance with Passive House principles. The project features a well-planned architectural layout with ground-level duplex apartments and upper floors offering studio to three-bedroom units. Retail and business spaces are integrated alongside residential amenities such as a fitness area and shared workspaces.
The building includes two staircases and one elevator for vertical circulation. Its massing and layout are carefully designed to balance functionality, natural light, and urban context. Rear open parking with EV-ready infrastructure further enhances the modern and sustainable design approach.
The mechanical system includes a VRF system for commercial spaces, allowing simultaneous heating and cooling with energy recovery. Residential units are served by multi-zone split systems for optimal comfort. A high-efficiency energy recovery ventilation system, with over 77% efficiency, supports Passive House performance goals.
Complete plumbing systems were designed, including domestic cold and hot water, stormwater (primary and secondary), and sanitary waste and vent systems. High-efficiency electric water heaters are used for both residential units and commercial spaces.
The fire protection system is designed in accordance with NFPA 13 standards and includes dry sprinkler systems in garage areas exposed to freezing conditions. The system is carefully coordinated with the building’s mixed-use occupancy to ensure full compliance and effective coverage.
Electrical systems include power distribution, submetering for residential and commercial units, interior lighting, emergency and egress lighting, and fire alarm systems. The lighting design emphasizes energy efficiency using LED fixtures and daylight controls in compliance with applicable codes.
Our engineering team collaborated closely with all disciplines to coordinate equipment clearances, soffit requirements, and overall system integration. Coordination with the Passive House consultant and architect improved the energy model’s compliance margin, resulting in a balanced design that achieves high performance while maintaining cost efficiency and architectural intent.