Energy efficiency is an important consideration for every homeowner. The Home Energy Rating System (HERS) Program is designed to help identify and fix issues, recognize areas for improvement, and compare the energy efficiency of California’s homes.
The HERS Program, also called the Field Verification and Diagnostic Testing Program, is a way to ensure that the various features of a home meet the California Building Energy Efficiency Standards (Energy Code). If work requires HERS testing, a rater will perform field verification and diagnostic testing on the appropriate features. If the system fails, the contractor is required to fix it.
The information below contains resources for homeowners and current or potential providers as well as literature pertaining to the HERS Program. Also included below is an FAQ.
When making a home alteration (for example, changing the HVAC system) or building an accessory dwelling unit, a homeowner can ask their rater (or installer) to see the completed HERS forms. Although many contractors have HERS raters they work with, a homeowner has the right to find and hire a rater who is independent of the contractor.
Depending on the work being done, HERS testing may be mandatory. Properly permitted work will trigger any necessary HERS testing. A contractor should understand and be able to explain permitting requirements to the homeowner. HERS testing should be part of this discussion.
It is the homeowner’s right to hire their HERS rater, but contractors may offer to take that responsibility. The homeowner should be aware of what to expect and ensure that the rater is a HERS provider certified Field Verification and Diagnostic Testing rater.
Approved by the CEC, HERS providers are companies who train, certify, and oversee the performance and behavior of HERS raters. They are also approved to operate data registries. A registry is where project compliance forms (the forms hosting the data on the particular energy efficiency feature) are completed and stored for review by the builder or contractor, building department officials, CEC staff, and the building owner. These registries may be found on the provider’s website and may be accessible to the homeowner.
HERS raters charge a variable fee. Ask for rates from raters or your contractor for more information regarding costs. Many contractors have established relationships with rater companies and have fixed these rates. There may be further costs for added services such as permit processing.
The rater should identify themselves with a photo badge and explain the tests to be performed. A visit will vary in length depending on the features being measured.
The rater will inspect and interact with the home’s various features (HVAC equipment, air ducts and vents, and thermostat). Most visits also require access to the home's circuit breaker panel. The tests could require walking on the roof or going inside an attic or crawlspace. You might be asked to close windows and exterior doors and turn off your clothes dryer or bathroom fan, as these will affect HERS testing. As a rater collects information, they might take photos of their instruments and conditions adjacent to the work.
Raters are also expected to explain that the HERS provider is required to perform quality assurance on the rater's work, and that the provider might contact the homeowner in the following weeks to schedule a quality assurance visit. This is to ensure that the rater is accurately testing and reporting at this home and many more throughout the year.
The presence, or even the suspicion, of asbestos used in duct insulation or sealing can exempt some tests such as duct leakage testing. However, even if no tests are performed, HERS documentation is still required to close the permit. Ask for a written statement from the contractor or rater about any exceptional conditions.
For more information about identification and abatement, review the CSLB's consumers' guide to asbestos - PDF .
If you are concerned about the quality of work, or if you experience problems with the system, first contact the installer. If the issue persists contact the California State Licensing Board (CSLB) who oversees contractor licensing . A consumer can find a licensed contractor, check a license, file a complaint, and more.
If concerned about the work done by a rater, contact that rater’s provider explaining the full circumstances of the issue.
When constructing multifamily homes under the 2019 Building Energy Efficiency Standards (Energy Code ) documentation of continuous supply or continuous exhaust ventilation installations must be accompanied by a compartment leakage (i.e., blower door) test. For many active projects, this test is not listed on the certificate of compliance (CF1R-PRF-01-E), as it is not a measure. However, the test procedure described in RA3.8 is necessary to complete the compartment leakage worksheets (MCH-24) at the installation and verification (CF2R and CF3R) stages.
Projects modeled using compliance software prior to the release of CBECC-Res 2019.2 should be revisited immediately to clarify expectations. Energy Code plans do not need to be revised or re-registered.
C urrent versions of approved compliance software make this expectation clearer. In the HERS feature summary on the CF1R-PRF-01-E form, there is a new detail under building-level verifications: "Enclosure air leakage for each dwelling unit." Note that the HERS data registries will require a user to complete the MCH-24 worksheet once a dwelling unit's MCH-27 worksheet has been started. The MCH-24 must be completed before the MCH-27 can be registered.
Two compliance options are given in Section 150.0(o)1E:
Multifamily attached dwelling units shall have mechanical ventilation airflow provided at rates in accordance with Equation 150.0-B [ASHRAE 62.2:4.1.1], and comply with one of the following subsections i or ii below. When subsection ii below is utilized for compliance, all dwelling units in the multifamily building shall use the same ventilation system type.
More about this topic can be found in the Residential Compliance Manual section 4.6.3. Builders are reminded to coordinate early with installing contractors and HERS raters to plan for field tests and verifications.