News Brief

California Adopts Nation's First Statewide Green Building Code

In a unanimous January 2010 decision, the California Building Standards Commission approved the Green Building Standards Code—a.k.a. “Calgreen”—the first mandatory statewide green construction code to be adopted in the U.S.

Scheduled to take effect in January 2011, Calgreen will require all new buildings to reduce water consumption by 20%; divert 50% of construction waste from landfills; separately meter indoor and outdoor water use (nonresidential only); and submit to mandatory inspections of mechanical system equipment (nonresidential buildings over 10,000 ft2, 930 m2, only). According to the California Air Resources Board, these provisions should reduce California’s greenhouse gas emissions by 3 million metric tons carbon-equivalent by 2020.

Calgreen was developed from voluntary green building standards enacted across the state in 2008 (see

EBN Sept. 2008), and it does not preclude local jurisdictions from instituting stricter green building regulations, which more than 50 California municipalities already have in place.


Published February 1, 2010

Ward, A. (2010, February 1). California Adopts Nation's First Statewide Green Building Code. Retrieved from

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February 1, 2011 - 7:09 am

We have developed the unofficial "CALGreen Companion Guide for LEED Projects" that aims to reduce the paperwork burden on LEED-NC projects that must now meet CALGreen mandatory provisions. View the report at