California On the Green Cutting Edge Again

This new house cuts cooling loads by using deep overhangs, porches, and high-performance windows, and by keeping existing trees where possible. Credit: Florida Solar Energy Center.

The eyes of the nation are once again upon California for making bold steps in the water efficiency, energy efficiency, and global climate change arenas. The California Department of Housing and Community Development has issued mandatory green building codes—the first statewide green building codes in the nation—effective beginning in 2011.

The California Green Building Standards (CALGreen) Code, a part of the Title 24 building codes, is so new that I can’t even find a copy of the code that doesn’t have “draft” next to the title. Most of us will not notice a difference right away. But builders will. Unfortunately, because of the downturn in the new housing market, new home builders will have plenty of time to bone-up on the new code.

Here are some highlights for residential builders:

New homes must be built to use 20% less water inside than a baseline established in the code. “Prescriptive” approach: 1.28 gallon/flush toilets, 2 gallon/minute showerheads (total for multiple showerheads), and low-flow faucets. “Performance” approach: demonstrated water use reductions based on all potable water uses.

Each house has to have a water controller for landscaping that is weather sensitive or sensitive to soil moisture content.

All openings in the building envelope—for electric, gas, and plumbing lines for example—between conditioned and unconditioned space to be sealed.

50% of construction waste to be recycled.

Each new house should come with an Operations and Maintenance Manual.

Paints, coatings, carpets, carpet backings and adhesives, floor coverings, and composite wood products should not off-gas volatile organic compounds, such as formaldehyde, above an amount that is safe for the health of occupants.

Bathroom exhaust fans should be Energy Star-labeled and exhaust moist air to the outside of the house.

Heating, air conditioning, and ventilation systems should be designed and sized according to standards that ensure efficiency and comfort.

If you are a builder and want some help understanding and complying with the new CALGreen code, contact your local home builders association, or contact Build It Green California, which offers training and materials that will help you comply with the new code.