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Architects: Hennebery Eddy Architects
- Area: 13800 ft²
- Year: 2010
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Photographs:Stephen Miller, Nic Lehoux
Text description provided by the architects. As part of a bond measure to expand classroom space, Portland Community College (PCC), Oregon's largest institution of higher learning, purchased a 15-acre site in Newberg, Oregon, to develop a new educational facility. As the first building on the site, creating a welcoming sense of place was critical to the success of the campus. The large, south-facing roof reaches beyond the building’s shell to create a sheltered entry plaza – the front door to the campus.
The Portland Community College Newberg Center has been designed to be the first Net-Zero higher education building in Oregon and the second in the United States. To achieve Net-Zero (defined as generating as much energy as it consumes over the course of a year), the building was designed to reduce overall energy consumption by 80% compared to standard higher education academic buildings in the United States. The remaining energy needs are met with a 100kW, rooftop-mounted, solar panel array.
To reduce the building’s energy use by over 15%, skylights in the classrooms and administrative area are integrated into a sloped ceiling system designed to provide even and diffused light without the need for electric lights. Skylight louvers track the lighting level in the room and open and close as necessary to maintain comfortable light levels. In the large Commons area, tall glass walls allow daylight deep into the building.
Fresh air is provided through louvers located on the exterior walls of the building. When fresh air is needed, the louvers automatically open. With the help of roof-mounted ventilation turbines, cool outside air is drawn in through the louvers while hot air is released through the five stacks along the building's central spine in what is known as the "Stack Effect" - the tendency for hot air to rise. The ventilation turbines encourage the "Stack Effect" by spinning at very small wind speeds. This motion creates a vacuum on their leading edge that helps pull hot air out of the building.
In addition to creating an efficient building, energy savings has been achieved by expanding the thermal comfort range 1degree in each direction. PCC's standard temperature range is 69 degrees F for heating and 77 degrees F for cooling. At the Newberg Center, the range has been set to 68 degrees F for heating and 78 degrees F for cooling. Fans in the classrooms, offices, and Commons help keep the building comfortable on hot days by making the building feel 3 degrees cooler through air movement.
The louver system, in conjunction with the exposed concrete floor and concrete shear walls, also helps keep the building cool. During the warmer months of the year, the exposed concrete walls and floor act as thermal mass, absorbing heat from the surrounding air during the day to keep the indoor temperature cool. At night, the louver system opens to allow the cool night air to move through the building, expelling hot air out through the stacks and removing the built-up heat from the concrete.
Heat is provided through a radiant slab system - plastic tubing embedded in the concrete floor. Warm water circulating through the tubes warms the concrete floor to provide a consistent even indoor temperature. During colder months, 90 degree water in the tubing will provide an ambient temperature of 68 degrees. Radiant systems are efficient because they heat the people instead of the air while avoiding uncomfortable drafts like forced air.
Through sustainable design, the building uses 55.5% less energy than allowed by the Oregon Energy Code. The remaining energy needs are generated through a 100kW rooftop photovoltaic system – a 25kW bi-facial solar panel array that covers an outdoor courtyard and a 75kW array mounted on the standing seam roof. To be truly "Net-Zero" the building systems and equipment were selected to use only electricity for power – no natural gas.
The building's roof and walls were built using Structurally Insulated Panels (SIPS) - thick sections of foam insulation sandwiched between two layers of oriented strand board. The panels provide high R-values for insulating the building, reduce thermal bridging, and create a tight building to prevent heat loss through air infiltration. The patterning of solid and glass in the building's glass walls help maximize daylight while maintaining appropriate levels of insulation.
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