CALGreen- Its Impact Upon New Construction in California

On January 1, 2011, the 2010 California Green Building Standards Code (also known as CALGreen) went into effect. Its green building measures have been adopted by most cities and counties throughout the state. Because it is so new, its full implications are not clear and may indeed vary from one municipality to another; however, it will certainly have a significant impact on new construction, both residential and nonresidential. Its purpose is to encourage sustainable construction practices which will minimize the negative impact of new buildings upon the environment. The measures are divided into 5 major categories:

1) Planning and design
2) Energy efficiency
3) Water efficiency and conservation
4) Material conservation and resource efficiency
5) Environmental quality

Some of the measures are mandatory, while others are voluntary (at the discretion of the local building agency). Here are some examples of the residential mandatory measures:

1) Planning and design
During construction, the building site must be maintained in such a way as to manage storm water drainage and minimize erosion.

2) Energy efficiency
Buildings must achieve at least a 15 percent reduction in energy usage when compared to the State’s mandatory energy efficiency standards; previously, buildings only had to meet the State’s mandatory energy efficiency standards. Although considered mandatory, it is not clear whether all building agencies will require the additional 15 percent reduction in energy usage.

3) Water efficiency and conservation
Indoor water usage must be reduced by at least 20% compared to what is allowed by the California Building Standards Code. In other words, the maximum allowable flow rate for plumbing fixtures such as showerheads, faucets and toilets is reduced by 20%. Note: where a single shower is served by multiple showerheads (as is popular in many newer bathrooms), the combined flow rate of all the showerheads cannot exceed the maximum flow rate for a single showerhead (2 gallons/minute).
Outdoor water usage must also be reduced. For instance, new irrigation system controllers must be weather-based or soil moisture-based and automatically adjust the amount of water usage in response to changes in plants’ needs or weather conditions.

4) Material conservation and resource efficiency
At least 50 percent of construction waste and demolition debris must be recycled. A construction waste management plan which documents the amount of recycling must be submitted and approved.
At the time of final inspection, documentation must be given to the building occupant that details the maintenance and operation of critical conservation equipment, such as HVAC systems, water heaters, major appliances, irrigation systems, gutters, downspouts, etc.

5) Environmental quality
To minimize air pollution, finish materials (such as adhesives, sealants, paint and carpeting) must comply with statewide VOC (volatile organic compounds) limits. Documentation must be available in the form of manufacturer’s specifications or field verification.
The moisture content of building materials (such as wall and floor framing) prior to enclosure must not exceed 19%, to be verified by use of a moisture meter.
Bathroom exhaust fans must be Energy Star compliant and be controlled by a humidistat.

The onus falls on architects, designers and/or builders to provide the necessary documentation verifying compliance with CALGreen standards. Building product manufacturers will also have to provide certain documentation if they want their products to be used in new buildings.

Voluntary measures, which will not be discussed in this article, establish additional building methods to be implemented in each of the 5 categories discussed above, along with the requisite documentation.

Due to the complexity of the CALGreen standards, homeowners should consult their design professional for additional details.