Center for the Built Environment (CBE)
University of California at Berkeley
A National Science Foundation Industry/University Cooperative Research Center since 1997
Innovative building technologies will improve the environmental quality, energy efficiency, and workplace productivity of commercial buildings
Center Mission and Rationale
Improving the quality of indoor environments and enhancing the energy performance of commercial buildings could lead to productivity gains and operating cost reductions worth hundreds of billions of dollars in the U.S. alone. Despite this huge potential, building research as a percentage of sales is well below that of other industries. In May 1997, a group of industry and government leaders teamed up with faculty and researchers at the University of California, Berkeley, to address the challenges of creating high-quality buildings. The result was the Center for the Built Environment (CBE), with the mission of providing timely, unbiased information on promising technologies and creating a dynamic, collaborative setting where people can develop ideas for improving the design and operation of commercial buildings.
CBE conducts a variety of building research projects, ranging from the evaluation and development of new building technologies that reduce energy use, improve environmental quality, enhance occupant comfort, and increase productivity, to tools that "take the pulse" of buildings in operation, enabling everyone in the building process to learn how a building actually performs in practice.
Current and recent CBE research includes:
Underfloor air distribution
Individual control of the indoor environment
Web-based occupant surveys of indoor environmental quality
Benchmarks of building energy efficiency
Operable windows in office buildings
Impact of ventilation on workplace productivity
Using occupant feedback to improve building operations
Wireless sensor networks for improved building control
Speech privacy in offices.
Since the building industry involves a mix of disciplines, professions, and physical processes, an interdisciplinary approach is essential. CBE draws upon the expertise of 15 faculty in six departments across the UC-Berkeley campus, as well as staff scientists at Lawrence Berkeley National Laboratory and full-time in-house research specialists. Fourteen students are currently assisting the Center in carrying out its research.
In addition to participating in the Industry/University Cooperative Research Centers Program, CBE researchers are active in the following:
- Modeling Human Comfort: detailed analytical model of human
thermoregulatory physiology, matched to human subjective responses,
capable of evaluating complex thermal environments
- Reducing Building Energy Use: projects ranging from alternatives
to compressor-based air conditioners in housing, to energy rating tools
for windows, to technology reviews for the Federal Energy Management
- Wind Tunnel and Solar Modeling: evaluation of the interaction
of building design with wind, daylight, and other environmental influences
- Revising Thermal Comfort Standards: development of an alternative
field-based standard for naturally ventilated buildings.
Special Center Activities
During the past two years, many of CBE's projects have produced significant results. The following projects have publicly disclosed findings:
- Supply Fan Energy Use in Pressurized Underfloor Air Distribution
Systems: This study explored the impact of various design assumptions
on the supply fan energy consumption of pressurized underfloor plenum
systems, as compared to that of traditional overhead constant air volume
and variable air volume systems.
- Team Spaces and Collaboration: Links to the Physical Environment:
Team workspace is a specific type of alternative office design to support
the activities of highly interactive, multi-disciplinary teams of knowledge
workers. The design normally provides individual workspaces for private
concentrated work, combined with nearby shared open spaces for group
work. The move toward this combination of group and individual spaces
is motivated by new work models that emphasize self-directed, team-based
work processes and projects. CBE conducted a pilot survey of team workspace
with the following objectives: (1) to study the impact of team workspace
design on user satisfaction and group interaction, and (2) to test new
survey methods and metrics for assessing the performance of team workspace.
- Mixed-Mode Office Buildings: Occupant Satisfaction and Control:
Mixed-mode (MM) strategies have the potential to offer the best of all
worlds by using natural ventilation to provide occupant control, high
ventilation rates, and reduced HVAC energy while using air-conditioning
to maintain comfort as necessary. A successful MM design will produce
a cost-effective, comfortable, relatively low-energy building that can
be easily adapted to changing building uses and HVAC load conditions.
This case study project evaluated the successes and failures of three
such buildings in California.
- Responding to Thermal Sensation Complaints in Buildings: This
report describes a new strategy for managing thermal sensation complaints
that occur when the building systems affecting thermal sensation are
operating normally. Thermal sensation complaints of this type account
for more than half of all thermal sensation complaints handled by facility
- Underfloor Air Supply Plenums: This report contains results
of a field test of minimum effective plenum height. This report shows
that very low-height plenums function effectively for underfloor air
- The Impact of Ventilation Control Methods on Productivity, Energy
Use and Health: This report describes an analysis of worker performance
at a hospital call center. The study found significant correlation between
work performance and factors related to indoor environmental quality.
A core strength of CBE is that its membership mirrors the diversity of the building industry. All of CBE's members plan to use advances developed by CBE in their businesses.
Most of CBE's facilities are housed at the UC-Berkeley College of Environmental Design. CBE's equipment and instrumentation includes a Controlled Environment Chamber, designed to resemble a contemporary office while allowing precise control over the temperature, humidity, ventilation, and lighting in the space; a Boundary Layer Wind Tunnel, which simulates the natural wind over models of the built environment in order to predict wind effects at full scale; a unique segmented thermal manikin for studying thermal comfort and environmental control provided by building systems; and an instrumented cart that makes detailed measurements of the physical environment from ankle level to head height. The Center also has a wide array of portable equipment for acquiring and analyzing data from experiments in the field as well as in the laboratory, including infrared thermographs, heat flux meters, flow metering hoods, tracer gas systems, flow visualization systems, electric power meters, instrumentation for measuring the detailed thermal and luminous characteristics of building interiors, and portable weather stations for measuring exterior microclimates. Shared and/or off-site facilities include a full-scale testbed underfloor air facility; sky simulators for modeling daylight in buildings (developed with Lawrence Berkeley National Laboratory with funding from the U.S. Department of Energy); and a large Heliodon with a collimated beam and a miniature point-of-view video camera for analyzing solar access and shading (developed with the Pacific Energy Center, San Francisco).
Center for the Built Environment
University of California-Berkeley
390 Wurster Hall #1839
Berkeley, CA 94720-1839
Tel (510) 642-4950 * Fax (510) 643-5571
Center Director: Dr. Edward A. Arens
Center Evaluator: Dr. Howard Levine
(510) 849-0358 * email@example.com