55 PALISADE AVENUE YONKERS,NY 10701

A new outpatient rehabilitation building with a hydrotherapy pool hall on the lower level, a therapy gym and treatment rooms on the floors above and a roof with the main plant. A pool hall puts a constant moisture load on the air, so the ventilation and dehumidification have to be sized separately from the clinical floors, and every pipe and duct in the hall must resist chlorine and humidity. Like every New York project, the design also has to satisfy the NYC Construction Codes and the city's energy code requirements.

Mechanical: we scheduled ventilation room by room for about 30,500 ft² of rooms, with the highest outdoor-air rate on pool hall. Heating and cooling come from a VRF heat pump system of 4 outdoor units totalling about 54 tons and 52 indoor units, backed by 2 12.5-ton gas-fired rooftop units and 1 energy-recovery ventilator. A dedicated dehumidifying unit holds the hall at 84°F and 55% relative humidity, with stainless steel ductwork, a separate exhaust and a gas-fired pool heater and filtration plant. Electrical: we scheduled the power connection for every rooftop unit, VRF unit, fan, heater and pump — voltage, phase, minimum circuit ampacity and overcurrent protection — and sized the building service for the connected load. Plumbing: A triplex variable-speed booster set supplies domestic water, two 119-gallon gas-fired heaters supply hot water, the pool has its own make-up, overflow and backwash piping, and a duplex sump drains the lower level. Fire protection: a wet sprinkler system on a 6-inch combined sprinkler and standpipe riser with a fire pump and jockey pump, hydraulically calculated at about 520 gpm against the city hydrant test. We also prepared the COMcheck energy analysis, the backflow prevention applications and the mechanical, plumbing and sprinkler sets for filing.