The new headquarters of Integrated Design Associates (IDeAs) Inc. is the United State’s first commercial office building designed to meet a net-zero energy/net-zero carbon emissions goal. When IDeAs bought a 7,200-square-foot former bank branch to retrofit for its new headquarters, IDeAs principal David Kaneda saw an opportunity to bring the concept of a net-zero energy building to life. Coined the Z2 building, the combination of energy efficiency and renewable energy solutions makes this building one of a kind.

In addition to an innovative HVAC system, the building takes advantage of useable green spaces and renewable energy from photovoltaics. The electrical system is tied into the grid, so it will draw power at night when there is no sunlight and deliver power back to the grid when more energy is generated than is being used during the day. The result is designed to be “net zero” in overall energy use.

The design of the HVAC system incorporates a geothermal heat pump that produces both chilled and hot water. A radiant floor system with cross-linked counter flow tubing uses the water to convey heating and cooling to the space. Because the system operates at higher efficiency levels, the radiant system can use higher water temperatures to provide effective cooling and lower water temperatures to provide effective heating. This unique HVAC system maximizes performance and indoor air quality, while keeping construction costs comparable to more traditional designs. The building’s energy efficiency is estimated to be 40 percent below 2005 California Title 24 energy requirements.

“All of the technologies we are using are readily available. Some of them are more expensive from a first-cost standpoint, but the reduction in energy use will pay long term dividends,” says Kaneda. “And, it’s the right thing to do from the standpoint of reducing our impact on the environment.”