The Nitty-Gritty on “Green”
Harker’s long-held commitment to environmental issues informed every decision in the current capital expansion project, and environmentally focused features have been incorporated into the design of the new science and technology center also known as Nichols Hall, which is designed to be LEED-certified (Leadership in Energy and Environmental Design).
According to the U.S. Green Building Council’s Web site, “LEED promotes a whole-building approach to sustainability by recognizing performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection, and indoor environmental quality.” LEED certification is based on a point system recognizing performance in the aforementioned five areas. XL Construction Corporation and DES Architects + Engineers, Inc. have designed the building so that it is on target to become LEED silver certified, which ranges from 37 to 43 points.
During production, 95 percent of the construction debris generated by demolition and construction were sent to recycling facilities instead of landfills. Additionally, more than 10 percent of the materials – steel, concrete, carpet, casework – used for construction are manufactured from post-consumer and pre-consumer recycled content. Eighty percent of the steel content itself is recycled. All of the paint, adhesives, sealants, carpet and other products used are low VOC and the wood products used have low urea-formaldehyde, earning the building four points for improving the indoor environmental quality. Air quality was also monitored during construction and before occupancy. All the air handlers were cleaned and capped after each day of work to prevent dust collection and no combustion vehicles were allowed on site during construction. Once the construction was done, there was a flush out period to ensure good air quality.
Since the area where Nichols Hall stands was originally a field and no buildings were demolished for the construction of the new science center, the location selected earns the building one point under sustainable site development. Nichols Hall also earns another point for community development, because the school has pedestrian access to residential neighborhoods and shopping centers. The proximity to bus stops, availability of bike racks and locker rooms, limited parking capacity and preferred parking for carpools and low-emitting and fuel efficient vehicles encourage the community to use alternative transportation, giving the building an additional four LEED points.
The building also has bioswales, turf cell paving and a green roof that provide a storm water management system. The bioswales, located around the building and alongside the parking lot, act as a natural earthen filter for the rainwater before it goes to San Tomas Aquinos Creek on its way to the bay. The turf cell paving effectively absorbs rainwater into the ground and minimizes storm water runoff and also preserves the soil from human activity. The green roof has a two-fold purpose; while the vegetation filters rainwater particulates and reduces storm water runoff, the green roof also acts as a natural insulator, keeping the heat in the building during the winter and out during the summer. The green modules as well as the surrounding reflective white coating on the roof help minimize the heat island effect caused by solar absorption of traditional black rooftops.
Nichols Hall also uses targeted exterior lighting and low-contrast yellow lighting to reduce undesirable light and night sky pollution. The interior lighting is designed to maximize brightness throughout the building while minimizing excessive energy use. For example, the recessed lighting used in the atrium decreases glare and also lights up large areas without taking up a lot of space. XL Construction has also installed occupancy sensors in all the rooms to minimize power consumption, improving the indoor environmental quality.
The use of water efficient features allow the building to use 40 percent less water than a typical building of the same size. These features include low-flow sinks, also included in the labs, as well as dual-flush toilets and ultra-low flush urinals, which use only 0.125 gallons per flush.
Additionally, the building operates 27-33 percent more energy efficiently than a baseline building of the same size due to features like the improved air handling system, heating, lighting, photovoltaic cells and building envelope.
The building envelope includes the low-emissivity glass windows used for the atrium and rotunda and the green roof. The polycrystalline solar panels will generate more than 2.5 percent of the energy used, offsetting a significant amount of greenhouse gases. The efficient HVAC (heating, ventilating and air conditioning) system will help the building consume $30,000 less in electricity annually with the help of features like the directive/indirect evaporative cooling air handlers that use one-tenth the amount of electricity generated by regular air conditioners that use compressors. Instead of using Freons, the air conditioning system uses enhanced refrigerant made entirely of water, so no ozone-depleting chemicals are used within the building. Also, the HVAC system uses air circulated from outside and has more air changes than required by code, ensuring good air quality indoors. To increase thermal comfort, each room has individual temperature controls to maximize energy efficiency and comfort for building occupants.
Additional points will also be considered for educating the community and going above and beyond the requirements in energy efficiency. With a rolling display of the solar panel energy production as well as displays explaining all the LEED-certified features of the building, students can learn just how “green” the building is.
Tags: Green Initiatives