At the southern tip of Manhattan, SoMA at 25 Water Street is now home to 1,320 rental apartments inside a 1.1 million-square-foot building that was originally designed as a bank operations center for computing equipment.
For contractors, one of the most relevant parts of the conversion is what happened at the exterior. The original building had a masonry facade with limited windows at the lower levels. Instead of stripping the whole exterior, the team leaned into selective demolition, installed new insulated window-wall units where needed, and refinished remaining brick in a new white color. The approach helped keep the existing building largely intact while improving views, daylight, and thermal performance.
Daylight was a driving constraint. To bring light deeper into the floorplates, the project carved two lightwells through the building core. Creating those openings required systematic disassembly of floor slab sections across 22 stories, with material removed through slots cut into the facade. The space “given back” to the lightwells was offset by a 10-story overbuild that brought the structure to 32 stories.
Supporting the overbuild, lightwells, and new vertical circulation meant extensive structural reinforcement. To avoid foundation upgrades, the team developed a lateral reinforcement system that threaded steel truss braces through the building to support existing and new elements. That kind of solution only works when structural and facade work are sequenced tightly, since exterior openings, temporary conditions, and interior demo all collide fast on a conversion job.
Pavarini McGovern broke the facade scope into phases. Levels 2 through 15 used unitized ribbon windows. Levels 16 through 22 involved removal and replacement of punch windows. The overbuild added new unitized window wall and metal panel, plus storefront work at the ground level. The two-year schedule depended on running multiple subcontractors at once, with up to 800 workers on site for almost a year, and daily onboarding and training to keep crews moving.
Resilience and conservation also shaped the work in a coastal flood risk area. Residential uses were placed more than 14 feet above the floodplain, with a tiered lobby strategy and multiple flood protection systems, including a flood-proof barrier, marine storefront glazing, and dry flood-proofing walls. By retaining more than 90% of the building’s structural elements, the team estimated it avoided 26,000 to 35,000 metric tons of embodied carbon. The building achieved LEED v4 BD+C Silver certification.
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