NVIT’s Green Sustainable Campus

NVIT’s Eagles’ Perch campus is an example of a green sustainable building, one that is beneficial to both humans and ecosystems. The 4,519 sq m building includes classrooms, faculty offices, social spaces, labs, a bookstore, a cafeteria, and a library and was built with an integrated design approach to ensure that green building principles and sustainability were incorporated.

Green building principles encourage the integration of buildings and infrastructure with local natural features, limiting environmental impacts on ecosystems and watersheds. Some of the features of the campus that reflect these principles are:

-       The primary materials used were concrete and wood, based on local availability and cultural significance. Floor slabs and shear walls are poured-in-place exposed concrete with 30-50% recycled fly-ash content, readily available from two local batch plants. The structural system is highly innovative in the combined use of wood and concrete. Glulaminated Douglas fir facetted columns were chosen as a design element representing the surrounding forest and the trees replaced by the building they support.

-       Lighting operation – in addition to natural day-lighting the building features 1.15W/sf lighting power density. Daylight sensors and occupancy sensors are provided to maximize energy saving potential.

-       Water conservation – the relatively dry climate requires a strategy for water use and management. The building is located below the elevation of natural water pressure to avoid pumping water uphill. Low flush toilets and fixtures are used to further reduce water consumption. The planted roof and landscaping strategy to maintain the native characteristics of the area minimizes the irrigation typically required for the landscaping of this type of facility.

-       This building was designed to perform 35% below the ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) standards for energy efficiency through:

Thermal mass - the exposed concrete of the suspended floor and roof slabs provides a heat sink during the high temperatures of summer, absorbing heat during the day and releasing it slowly during the night. During the winter, the combination of the earth-covered roof, R-30 insulation and concrete mass retain energy and minimize heat loads.

Efficient envelope - the wood rain screen wall assembly is R-20. The building has 35% glazing with thermally broken frames. Sliding yellow cedar sun screens with blades cutting off sun angles according to solar orientation further reduce cooling loads and glare. The lower section of the roof is planted with Kinnikinic, an indigenous, low-level creeping plant. This planted roof contributes to heating and cooling loads in the building, drawing from the inherent energy efficient qualities of the pit-houses historically on this site.

Natural ventilation and solar control are the primary strategies to achieve energy targets without adding cost. The system designed is a two-pipe fan coil system along the perimeter of the building, utilizing two high efficiency boilers and an air-cooled chiller. Natural ventilation is provided by user controlled operable windows along the perimeter, relief grilles between perimeter rooms and atrium, and sensored motorized operable windows in the ventilation atrium. The thermal chimney that is provided by the ventilation atrium reduces cooling loads during the spring and fall shoulder seasons. The primary energy saving strategies of thermal mass and natural ventilation draw from the pit-house and the extended tepee used in the past by the local native people.