Title 24, Part 6 is California's Building Energy Efficiency Standards — among the most stringent commercial energy codes in the United States. If you're building, expanding, or significantly renovating a commercial building in California, you'll need a compliant energy design before the building department issues a permit.
What Is Title 24, Part 6?
Title 24 is the California Code of Regulations governing building standards. Part 6 covers energy efficiency for both residential and nonresidential buildings. The California Energy Commission (CEC) updates the standards on an approximately three-year cycle. The 2022 Standards (effective January 2023) are currently enforced and include expanded requirements for solar-ready construction, heat pump readiness, and EV charging infrastructure.
When Does Title 24 Apply?
Title 24 energy compliance is required for: new construction (all new nonresidential buildings), additions (new conditioned floor area), alterations (work that modifies HVAC, lighting, or envelope systems beyond prescriptive thresholds), and change of occupancy when more restrictive energy requirements are triggered.
Prescriptive vs. Performance Compliance
Prescriptive Path
The prescriptive path requires that each building system (envelope, lighting, HVAC) individually meet minimum efficiency requirements listed in the standards. It is straightforward but inflexible — you can't trade efficiency gains in one system against deficiencies in another.
Performance Path
The performance path uses CEC-approved energy modeling software (typically EnergyPro or CBECC-Com) to demonstrate that the proposed building's total energy use is equal to or less than a code-compliant reference building. This path allows trade-offs and is used by most large or complex projects.
Key Systems Covered
Building Envelope
Roof insulation, wall insulation, fenestration (windows and skylights), and air sealing are all regulated. Climate zone determines the minimum R-values and maximum U-factors and solar heat gain coefficients (SHGC) for glazing.
Lighting
Indoor and outdoor lighting must meet power density limits (watts per square foot by space type) and include occupancy controls, daylight controls, and demand response capability in many applications.
HVAC
Equipment efficiency (EER, COP, IEER) must meet minimum values. Controls including economizers, demand-controlled ventilation (DCV), and setback thermostats are often required. The 2022 Standards push harder toward heat pump technology and refrigerant transition.
What the Compliance Package Includes
- CF-1N forms (project overview and compliance summary)
- Envelope compliance forms (roof, walls, fenestration schedules)
- Lighting compliance forms (indoor and outdoor power allowance calculations)
- Mechanical compliance forms (equipment schedules and controls)
- Energy model output if using the performance path
- Certificate of Compliance posted at the job site
Climate Zone Impact
California has 16 climate zones, and Title 24 requirements vary significantly by zone. Zone 6 (coastal Los Angeles) has very different envelope and HVAC requirements than Zone 14 (high desert). Your energy engineer must use the correct climate zone data — misidentification is a common error that causes plan check rejections.
Common Compliance Pitfalls
- Starting too late — energy analysis informs architectural decisions; beginning after design is finalized often forces expensive redesigns
- Wrong climate zone — building location must be assigned to the correct CEC climate zone
- Missing mandatory measures — some requirements apply regardless of compliance path and cannot be traded away
- Outdated software — compliance software must match the active code cycle
Title 24 and LEED
Title 24 compliance is a prerequisite for all California projects, not a substitute for LEED. LEED's energy credit measures improvement above a baseline that must already meet Title 24. In high-performance projects, the Title 24 performance compliance path and the LEED energy model are often run in parallel by the MEP engineer.
Next Steps
Engage your MEP engineer as early as schematic design. Compliance analysis that begins at design development or later limits your options and increases the risk of plan check delays.