Introduction
California's Title 24 energy code is one of the most comprehensive building energy standards in the country. For builders and developers working on new construction or major renovations in California, understanding Title 24 is not optional — it is a legal requirement that affects project design, contractor coordination, inspections, and permit close-out.
This guide covers the fundamentals of Title 24 Part 6 (the Building Energy Efficiency Standards), who the key compliance professionals are, what documents are required, and how the compliance process works from permit application to final sign-off.
What Is Title 24?
Title 24 is the California Code of Regulations, Title 24, which covers building standards across multiple parts. When most people in the construction industry refer to "Title 24," they mean Part 6: The Building Energy Efficiency Standards (BEES).
Part 6 is developed and enforced by the California Energy Commission (CEC) and sets minimum energy performance requirements for new buildings and additions and alterations to existing buildings. The standards apply to both residential and nonresidential buildings and cover systems including the building envelope (insulation, windows, air sealing), HVAC systems, water heating, lighting, electrical systems and EV charging readiness, and solar photovoltaic and battery storage (for new residential construction under the 2022 standards).
The CEC updates the Building Energy Efficiency Standards on a roughly three-year cycle. The most recent standards are the 2022 Title 24 Standards, which took effect January 1, 2023. Projects permitted on or after that date must comply with the 2022 standards.
Who Is Involved in Title 24 Compliance?
Title 24 compliance involves multiple professionals, each with a distinct role. Understanding who does what — and when — is critical for keeping a project on track.
The energy consultant (also called an ECC Writer or Title 24 analyst) prepares the compliance calculations before or during the permit application process. They use CEC-approved software to model the building and confirm that it meets the required energy budget. The output is the CF1R — the Certificate of Compliance — which is the foundational compliance document for the project. The energy consultant does not perform field work.
The HERS Rater is a CEC-certified, third-party field verifier who visits the job site after systems are installed to perform diagnostic testing and visual verification. Their work produces the CF3R — the Certificate of Verification — which confirms that HERS-required measures were installed correctly and perform as specified.
Licensed contractors are responsible for completing the CF2R — the Certificate of Installation — for each measure they install. This is a self-certification document attesting that the installation matches the CF1R requirements.
For nonresidential projects and some multifamily buildings, an Acceptance Tester performs functional testing of lighting controls, HVAC controls, and other building systems to confirm they operate as required.
The local building department is the authority having jurisdiction. They review submitted compliance documents at permit application, conduct inspections during construction, and verify that all required certificates are on file before issuing final approval.
Key Title 24 Compliance Documents
The CF1R (Certificate of Compliance) is prepared by the energy consultant and submitted with the building permit application. It lists all required energy measures and identifies which require HERS verification. This document drives everything else.
The CF2R (Certificate of Installation) is completed by each licensed installing contractor after their portion of the work is done. It is self-certified and submitted to the HERS Registry prior to HERS field verification.
The CF3R (Certificate of Verification) is generated by the HERS Rater through the HERS Registry after field testing is complete. It is required for permit final.
Title 24 Compliance: Step by Step
During the design phase, the project architect or designer works with an energy consultant to develop a compliant building design. At permit application, the energy consultant submits the CF1R. During construction, contractors install the systems and complete CF2R forms as their work is completed. For HERS field verification, the HERS Rater visits the site to perform testing — certain tests like insulation verification must occur before work is covered. For nonresidential and some multifamily projects, an Acceptance Tester performs functional testing. At permit final, the builder provides all required CF1R, CF2R, and CF3R documentation.
Special Requirements Under the 2022 Standards
The 2022 Title 24 Standards introduced several requirements builders need to know. The solar PV requirement was expanded significantly — extending the solar mandate to new high-rise multifamily buildings and many nonresidential building types, including offices, retail, schools, grocery stores, and warehouses.
Battery storage was also mandated, making California the first state to require both solar and battery storage for new construction. New single-family homes and other newly constructed residential buildings that require solar PV must also include a battery storage system with a minimum usable capacity of 7.5 kWh.
The 2022 standards also include stronger requirements for EV charging infrastructure, heat pump-ready space and water heating, and significantly increased efficiency requirements for water heating in new residential construction — making heat pump water heaters the most common path to compliance.
Common Title 24 Compliance Mistakes for Builders
Not engaging the energy consultant early enough is one of the most costly mistakes. Title 24 compliance must be designed in from the start. Last-minute compliance fixes are expensive and sometimes impossible without redesigning building systems.
Failing to schedule the HERS Rater at the right construction phase is another frequent problem. Insulation must be verified before drywall is installed. Duct testing must occur before final close-up. Missing these windows requires opening up finished work.
Assuming the energy consultant handles everything leads to gaps in the process. Field compliance — CF2R forms from contractors and CF3R certificates from the HERS Rater — requires coordination across multiple parties on site.
Finally, not verifying that installed products match the CF1R can derail a project. If a contractor substitutes a window or HVAC unit with a different model mid-project, the CF1R may need to be revised before HERS verification can proceed.
Conclusion
Title 24 compliance is a multi-step, multi-party process that runs from design through permit close-out. Understanding who is responsible for each document — the energy consultant's CF1R, the contractor's CF2R, and the HERS Rater's CF3R — is the foundation of managing a California construction project successfully.
Start compliance planning early, coordinate your HERS Rater before construction begins, and keep your compliance document chain organized. Those three habits will prevent the majority of delays builders encounter at permit final.