California's New Energy Standards

Taking just 119 days, the State of California recently passed Assembly Bill 970, which included emergency new standards for energy efficiency in new homes and commercial buildings. According to Don Kazama, the Building Standards Project Manager for the California Energy Commission (CEC), “We worked most holidays and an awful lot of overtime to get this done.” Starting on June 1, 2001, building features such as sealed ducts (or ducts in conditioned space), attic radiant barriers, more efficient windows (particularly lower solar heat gain coefficients), and thermostatic expansion valves on A/C units will be all but required for new buildings. These specific features are still characterized as options in the new standards, but meeting the code without them is very difficult and involves less practical tradeoffs. Kazama confirms that these measures were selected for their relative impact and ease of incorporation and because they were supported by existing data and analyses.

Although the measures have the support of a broad range of constituents—from the California Building Industry Association to the Natural Resources Defense Council—the standards were not achieved without controversy. Of particular note is the duct performance requirement. Builders must certify the duct system’s leakage with diagnostic testing, and 15% of all projects will be double-checked by Home Energy Rating System (HERS) raters for the CEC. There are currently about 60 raters with CEC certification in California, and Kazama expects this number to double or triple in the near future to support the growing demand for diagnostic testing.

The new standards apply to additions but not to remodeling of existing structures, with one exception: if an addition’s duct system ties into the existing structure’s ducting, the whole system must comply with the duct leakage requirement. “The new standards are expected to cut energy use in the State of California by 200 MW, or enough power for 200,000 California homes,” says Kazama.