Kern Business Journal October/November 2012

Page 23

OCT/NOV 2012

KERN BUSINESS JOURNAL

23

Courthouse features energy-saving innovations By Steve McConnell and Matthew Somerton

From small towns to urban centers, the nation’s courts serve the pursuit of justice across the land. As architects, we believe federal courthouses reflect societal values and are a vital part of the built environment. This summer, we welcomed a new U.S. Courthouse to Bakersfield. Designed under the federal General Services Administration Design Excellence Program, the building provides Kern County with a modern justice facility that invites public access through a distinct portico and reflects civic values of quality and stewardship. The building also addresses energy conservation and is expected to achieve LEED Gold Certification from the United States Green Building Council. The sustainability strategy developed for the courthouse marries modern technology and lessons from pre-modern “best practices” for buildings in hot climates. This high-tech/low-tech approach allows for public spaces and workspaces that maximize human comfort while dramatically reducing the amount of resources required to operate the building. In the end, this design approach enables the building to reduce energy consumption by 45 percent relative to a comparable new building. The low-tech, or “passive,” performance aspects of the design arise from simple goals: stop solar heat gain from entering the building to minimize mechanical cooling, provide ample daylight to reduce the need for electric lighting, and do all this through spaces and forms that elevate comfort and experience. A key innovation in this effort is a pro-

Photo courtesy of NBBJ

Lights from the new U.S. Courthouse in downtown Bakersfield reflect on the water of the city’s Central Park at Mill Creek.

gressive use of tilt-up concrete, a relatively low-tech construction method adapted and crafted through a collaborative design-build process. The articulated white concrete provides a well-refined finish, a robust structural frame and deep recesses, protecting it from direct sunlight. Furthermore, this construction method helped enable the project’s completion in half the typical time for such a project—just 30 months, instead of the usual 60 for typical federal courthouse projects. High-tech solutions boost energy efficiency and provide comfortable interior environments. For example, the courtroom is the first in the GSA’s portfolio to use 100 percent LED lighting, and the entire building is wired with daylight sensors that optimize light levels

and avoid unnecessary use of electric lights. Within office areas, the design team introduced active chilled beams, another first for a GSA courthouse, which circulates cold or hot water throughout the building to cool or warm air wherever needed. In the tall lobby space, a radiant floor heating system is used in winter months, and a displacement ventilation system delivers cool air through low wall registers. Both of these energy-efficient systems are designed to provide conditioning only where useful, and avoid the common pitfall of trying to warm or cool all of the air in a tall space. Finally, a rooftop solar hot water system provides 30 percent of the building’s demand, and a photovoltaic array of solar panels supplies 13 percent of the building’s electrical

needs. While new technologies enable great leaps in energy efficiency, the use of passive design strategies in the new U.S. Courthouse in Bakersfield is critical to achieving significant energy conservation. The ultimate goal of this project is to contribute to the evolving American standard for civic landmarks, which is rapidly expanding to include measures of performance, value and conservation. — Design partner Steve McConnell and project designer Matthew Somerton work at NBBJ, a global architecture and design firm with 10 offices around the world, including locations in Los Angeles and San Francisco.