NEW YORK - Since environmentalism and sustainability are important parts of its curriculum, New York City private school, Ethical Culture Fieldston School (ECFS) practiced what it has preached when it built its new $75 million campus expansion.

Green ideas including roofs with vegetation that are accessible to classes, waterless urinals, cisterns that capture rainwater for irrigation and maintenance, low-e glass glazing to reduce energy consumption, plus many recycled construction materials were used for the 47,000-square-foot middle school, 38,000-square-foot gym, 14,000-square-foot swimming pool, and another 34,000 square feet of renovation. The green focus could lead to a silver-level Leadership in Energy and Environmental Design (LEED) certification the school has applied for, according to New York-based Levien & Co., the school’s construction representative.

Architect, Cooper Robertson & Partners, New York; construction manager, Tishman Construction, New York; and many of the contractors were chosen for the project because of prior experience with green building.

While there are many types of conservation in the project, one of the major contributions to energy saving and heat recovery is the HVAC equipment. Ambrosino, DePinto & Schmieder, Consulting Engineers (ADS), New York, which specified the equipment, is an engineering firm specializing in green design and is a U.S. Green Building Council member with several LEED accredited professionals on staff.

One energy recycling example comes from the swimming pool’s comprehensive HVAC system, a DRY-O-TRON® model RS-162 manufactured by Dectron Inc. The 22,000-cfm dehumidifier not only keeps the 7,200-square-foot swimming and 115-spectator spaces in a constant 50 percent relative humidity, but it also recovers energy to provide free pool water heating for the school. If 100 percent pool water heating can’t be accomplished on extremely cold winter days, the dehumidifier has an on-board 540,000-Btu high-efficiency back-up boiler, according to Robert Senia, president of HVAC manufacturer’s representative SRS Enterprises, Brooklyn, N.Y.

While some schools attempt to save construction costs with a basic make-up air and exhaust system, ECFS officials opted for a commercial dehumidification system designed expressly for indoor pools, which requires higher upfront equipment costs, but significantly lower long-term operating costs. “Once we explained the indoor air quality (IAQ), energy saving, and short payback benefits of a state-of-the-art mechanical dehumidifier, other methods were never considered during the planning stages,” said Michael Ambrosino, principal, ADS.

The dehumidifier also uses another energy recovery method, Smart Saver, which preheats the unit’s 6,000-cfm outside air minimum requirement with hot exhaust air. Smart Saver is estimated to save the school $5,600 annually based on natural gas prices of $1/therm.

ADS’s attention to sustainability didn’t restrict the architect’s aesthetics, which includes a high 20-foot ceiling to give the pool a feeling of spaciousness. The airflow design within the space still provides indoor air comfort regardless of the high ceiling. From the rooftop dehumidifier, supply air is brought in high on the natatorium’s wall into a plenum that spans the entire width of the pool. Aesthetically, the plenum is recessed behind the grandstands and only the six spiral metal duct runs emerge visibly into the space along the ceiling.

Other HVAC equipment on the project also recovers heat. Installed by ASM Mechanical Systems, Brooklyn, N.Y., 100-percent outdoor air systems totaling 20,000 cfm for the new project’s middle school area and gymnasium utilize heat pipes to recover energy from the exhaust systems that save both heating and cooling energy.

Other equipment on the project includes an Andover Controls, Andover, Mass., building automation system, which will soon be retrofitted to also encompass the campus’ older buildings.

The ECFS is just another example of the emerging trend of schools functioning as environmental role models for their young impressionable school body. “Sustainability is becoming a resonant topic for many private schools that are seeking to expand and improve facilities,” according to Myra McGovern, spokesperson for the National Association of Independent Schools. “At the intersection of these two trends you see a huge growth in the number of green schools being built,” McGovern said.

Publication date: 11/19/2007