The Whitehall Building - SL Green
17 Battery Place
New York, NY
Adaptive Reuse of Pre-War Office Building

In order to attract tenants to a building constructed in 1902 and to convert the occupancy to one of mixed hotel/residential/commercial use, SL Green opted to upgrade the mechanical and electrical systems to a design standard consistent with year 2000 services. However, strict adherence to an established budget called for a diligent effort of adaptive reuse.

The refrigeration plant was renovated by replacing two aging 1,000-ton electric chillers, which utilized a phased-out-of-production refrigerant, with two new high-efficiency 850-ton electric driven chillers, using an environmentally-friendly refrigerant. New chilled water pumps and new main piping was installed.

Commercial spaces were retrofit with new HVAC systems serving the interior portions of each floor. A multiple of 15-ton water-cooled VAV units were utilized per floor. The units reject their heat to the existing cooling towers that were deemed suitable for adaptive reuse. The perimeter spaces continue to use the existing two-pipe fan-coil unit system. However, new outdoor air systems were incorporated into the interior systems to improve the pre-existing condition of poor ventilation. An electronic building automation and temperature control system was installed to monitor all critical points within the system and to aid in developing preventative maintenance programs.

The electrical design obviously included coordinating the power requirements for the chiller plant upgrade. The electrical service was reconfigured to separate the upper portion of the building (hotel/residential) from the lower portion (commercial). New electrical busduct risers serving the commercial tenant floors to provide 8 watts per square foot for lighting, and equipment were installed. The upgrade work also included designing electrical distribution, circuiting and fire alarm requirements for all common areas such as core toilets, elevator lobbies, etc., on the commercial tenant floors.

The project was constructed and commissioned within a narrow window of opportunity in the winter, when no mechanical refrigeration was anticipated, and when street-closure permits were available. All equipment was pre-purchased and the majority of the piping was prefabricated in order to adhere to the schedule. A major challenge determining a method of delivering equipment into the building through very tight space conditions without the need for dismantling/reassembly.

Despite the engineering and logistical challenges presented, the project was completed on-time and under budget.