The California Energy Commission updates the state’s Building Energy Efficiency Standards on a periodic basis usually every three years. The updates are made in consideration of the new technologies and techniques in energy efficiency for residential and non-residential structures.
The standards have once again been updated for 2016, which will be put into effect on Jan 1 2017; the current standards enforced as of this writing date back to 2008. Of course, the updates will introduce improvements in the current standards for new construction as well as for additions and alterations to buildings.
What are these updates? What are its effect on the environment and on utilities costs? Let’s take a look.
Since glass windows are one of the culprits, so to speak, of energy inefficiency in houses, the 2016 prescriptive measures reduces both the U-factor and the Solar Heat Gain Coefficient (SHGC) – down to 0.32 for U-factor and 0.25 for SHGC.
The U-factor refers to the rating provided to windows based on the amount of heat loss allowed. The rule of thumb: The lower the number, the lesser the heat loss; U-factors range from as low as 0.2 (low heat loss) to as high as 1.2 (high heat loss).
As such, the lower U-factor means higher energy savings for homeowners and lesser carbon footprints.
The SHGC refers to the quantity of heat passing through the glass window and into the interior areas of the building. The general rule: The lower the number, the lesser heat entering the interiors.
Thus, the lower SHGC required for residential structures in California means greater energy efficiency. Keep in mind that, in areas with hot climates like California, low SHGC is desirable but it is the opposite in areas with cold climates.
Note: In mild coastal zones, the SHGC requirements are not applicable (i.e., no minimum requirements)
But as with all rules, there are authorized exceptions. For example, you can install up to:
• 12 square feet of skylights with 0.30 SHGC and 0.55 U-factor
• 3 square feet of door glass at any performance level
• 3 square feet of tubular day lighting device at any performance level
When in doubt, your best course of action is to ask the professionals of NRG Compliance for more information. Keep in mind that violations of the standards can result in penalties ranging from fines to suspensions of licenses for either or both the homeowners and the contractors. Compliance is always better than the cures for non-compliance, to borrow a popular phrase.