345 Hudson Street
Transforming a 1930s Manhattan office building into one of New York’s most energy-efficient commercial properties. Winner of NYSERDA’s Empire Building Challenge.
The challenge
345 Hudson Street is a 17-story, nearly one-million-square-foot Art Deco office building owned by Hudson Square Properties. Built in 1931, the property relied on gas-fired steam heating and separate cooling systems that could not recover or exchange energy. Retaining this infrastructure would have left it exposed to increasingly stringent emissions limits and potential penalties under New York City’s Local Law 97. With lease turnover occurring on different timelines across the building, the transition had to be phased accordingly. The project required a strategy that coordinated infrastructure upgrades with tenant turnover, planned renovations and equipment replacement cycles while establishing a clear pathway to full electrification.
The system approach
URBS developed a full-building decarbonization roadmap that established the long-term system direction, implementation timeline and phased transition to all-electric heating and cooling. The roadmap coordinated central infrastructure upgrades with tenant-level improvements, allowing the existing steam system to be retired progressively without requiring a single disruptive overhaul. As part of the strategy, URBS introduced the first ambient-loop design in the New York market. The system allows thermal energy to move between floors through decentralized water-source heat pumps, reducing the need for centralized heating and cooling capacity. URBS also identified the required technologies, assembled the initial technical team and supported the successful application for $5 million in NYSERDA funding.