Energy, water, and space savings are three significant benefits that resulted from the modernization of the American Congress of Obstetricians and Gynecologists’ (ACOG) headquarters. The primary focus of the renovation was replacing the building systems, which were near the end of their expected functional life, while allowing the building to stay operational. The results include an approximately 50% annual energy savings and 1,000,000 gallons of annual water savings.
The existing system of floor-by-floor water cooled air conditioning units was replaced with a combination of variable refrigerant volume (VRV) and Dedicated Outdoor Air System (DOAS) infrastructure. The VRV DOAS system is powered by air cooled condensing units located on the roof, a design that was selected based on energy savings, controllability, and space gains in the tight ceiling plenum. A new energy recovery air handling unit on the roof captures and saves energy from the building’s toilet exhaust, and works with the highly efficient VRV DOAS system to improve HVAC energy efficiency by approximately 30% over the previous system. Switching to a refrigerant-based system from a water-based cooling tower also dramatically reduces the amount of water required to operate the building.
The design allowed the reuse of the existing ventilation air shaft as the location for the new outdoor air duct riser, minimizing the need for significant modifications to the existing structure. The new system also allowed ACOG to reclaim the square footage that had been required for mechanical rooms, resulting in a gain of more than 1,000 SF usable space per floor.
The building interiors also underwent a complete redesign. The new space includes a mix of open and private work areas and a conference center on the second floor that offers a board room, training room, teleconference room, and small conference rooms. New systems include LED lighting and VRV Fan Coil Units for cooling.