For multifamily projects built in the state of California, one of the typical compliance measures that most developers will encounter at some point is HERS testing. The Home Energy Rating System (HERS) is a set of protocols devised by the California Energy Commission (CEC) in order to verify the indoor air quality and energy efficiency of newly installed heating, ventilation, and cooling (HVAC) equipment. This quality assurance process is designed to bring greater benefits to the occupants and owners of newly constructed residential projects by ensuring that there is a minimal loss in air supply, proper moisture and pollutant control, and lower energy waste from the HVAC system. Although HERS testing is beneficial on its own, it isn’t always required in the state of California.

To know when HERS testing is mandatory, you must first know the classification of building you’re designing. There are two primary types of residential buildings according to the CEC: low-rise, and midrise/high-rise. A low-rise building is any residential structure that is 3 stories or less, a midrise building is 4-7 stories, and a high-rise building is 8 stories or more. It’s important to note that midrise and high-rise buildings follow the same set of laws in this regard, but the CEC still makes the distinction in terminology within the California Energy Code.

Under the 2016 Energy Code, newly constructed low-rise buildings (single family or multifamily) all have four mandatory tests: duct leakage, airflow, fan efficacy (otherwise known as “watt draw”), and IAQ (indoor air quality). These tests are designed to identify potential duct leakage from improper sealing, measure the amount of air being circulated throughout the residential units (as well as the amount of power being used to do so), and the effectiveness of the exhaust fans in the kitchen and/or bathrooms. These four tests will always be required on new low-rise construction projects in California, so this is important to note when developing projects of this nature.

Midrise and high-rise residential buildings do not have any mandatory HERS requirements under the 2016 California Energy Code cycle. This is because, according to the Energy Code, these buildings function in much the same way as nonresidential buildings, therefore the residential spaces do not explicitly require testing of this nature. However, within the energy models of these types of buildings, there is an option to take a credit for duct leakage testing for any amount of air handlers onsite. This will allow you to better comply with Title 24 energy standards by increasing your projected savings under the assumption that these tests will take place and verify proper construction and HVAC installation. (All of this applies to nonresidential buildings/spaces as well.)

VCA Green possesses a highly qualified team of HERS raters to perform these tests, create and analyze energy models for HERS compliance, and more. For energy consultation services such as these, please contact Moe Fakih below.

Moe Fakih, Principal
714-363-4700 x. 501

Contributing Writer: Burke Boydell, LEED AP Homes