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Sustainability Pays Off As a result, a review by the design team revealed that the project was within striking distance of being LEED certified, says project architect Rohit Saxena. Although construction had begun, the team was able to modify the design and, without much effort, add a few more sustainable design features. Green Planning Redeveloping a previously occupied campus site increased local density and preserved existing green space. To continue its efforts to minimize automotive traffic on campus, Emory built a shared parking garage a few miles away. Vehicles fueled by compressed gas and electricity shuttle people back and forth. "Getting the cars off the street sooner obviously cuts down on campus emissions," says John Fields, Emory's director of project management and construction. In lieu of cars and concrete, Emory has green spaces and walkways. HOK designed open-plan modules for both office and research spaces. They made the modules interchangeable and arranged them along outside walls. The abundant open space allows Emory to easily accommodate changes while improving interaction among researchers. Ninety percent of the building's lab and office spaces are on the edges, with windows to the outside. "Daylighting is an important criterion for LEED," says Saxena, "but we had already designed for daylight just because it makes sense to have natural light where people spend their time." Already, one prominent researcher has changed his mind about leaving the university because of the improved quality of the building's indoor environment. Each lab module has its own controls for lighting, piping, and heating, ventilation, and air-conditioning (HVAC). Access to these services is located outside each lab unit. The flexibility offered by this modular approach allows Emory to modify labs, at a lower cost, without affecting adjacent modules. The designers chose building materials low in emissions of volatile organic compounds (VOCs). The materials also have a high recycled content and are from renewable, local sources. Laboratory counters are from Trespa, a manufacturer of durable, fused composite material made from post-consumer and post-industrial waste and that uses no epoxy. Also, before Emory's faculty and staff moved in, office areas were flushed with 100 percent outside air to drive out any built-up VOCs. Energy Savings The Whitehead Research Building's energy recovery system includes four enthalpy wheels in the mechanical penthouse. These 20-foot (6-meter) diameter wheels use air exhausted from the facility to preheat outside air in the winter and to precool it in the summer. This system cost Emory about $450,000 to install but is expected to cut heating and cooling costs by $106,000 annually. "The simple payback of 4.2 years," says Fields, "will save us about $1 million in the decade that follows. We probably will have to replace the wheels, but we can do that much more inexpensively because that initial investment covered the construction of all the systems necessary to use the wheels." Laboratory buildings typically use 100 percent "one-pass" air, which is not recirculated but cleaned of contaminants and exhausted to the outside. Whitehead's system is more efficient. Return air from "clean" zones like offices is mixed back into the supply air, yielding about 75 percent one-pass air to all zones. Other energy-efficient measures include: • Glazing that reduces solar heat gain while admitting beneficial daylight • Occupancy sensors and photosensors that turn off electric lights when no one is in the room and that adapt to daylight levels • A robotic washing system that uses less water and energy and fewer chemicals than typical washers Emory's standard approach is to commission all new buildings before they open. This entails testing the building systems to make sure they operate as intended. This improves the efficiency of most buildings, but is especially important with laboratories, which use huge amounts of energy, have sophisticated control systems like fumehoods, and have special safety requirements. The commissioning should prevent Emory from spending time performing unexpected maintenance on equipment that isn't operating at an optimal level. Water Recovery Systems The building's stormwater harvesting system captures water from the roof and outdoor plaza and moves it to a large retention vault beneath the plaza. The water then is filtered and reused for on-site irrigation. Emory project manager Laura Case explains that the solution was simple and cost-effective. "We were already required by the county to build a detention vault to slow stormwater runoff from the roof and site. When we decided to go for LEED certification, it didn't take much additional effort to make the size of this underground detention vault three feet (one meter) deeper so it would hold about 70,000 gallons (265 kiloliters) of water." Case continues: "We also added a filter, a pump, and a bit of piping to hook this catchment area into the site's irrigation system." In addition, the site is planted with indigenous flora that requires less irrigation. The team recognized that the air-conditioning system would create a tremendous amount of condensate water, so this condensate is piped from air-handling units and chilled-water coils back into nearby cooling towers for use as makeup water. This system conserves water and diverts an estimated 2.5 million gallons (9,500 kiloliters) of water a year from the county's sanitary sewer system. This savings would satisfy the water needs of 100 people for 125 days. Good Business Sense The team fully expects the project, which came in below budget and ahead of schedule, to be LEED-certified when the performance results are measured in late 2002. The project has become a standard for all new Emory facilities. "I believe what we have done makes good business sense because it reduces building operating costs," explains Fields. "And it creates a healthy, attractive environment for our employees and students." The total cost of the LEED initiatives — about $990,000 — represents about 1.5 percent of the building's $66 million total construction cost. The savings in energy costs alone over the first decade will exceed the total initial cost of all the green-building features. Michael Miller, AIA, is managing principal at the Atlanta office of Hellmuth, Obata + Kassabaum, Inc. (HOK).
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