HVAC plays a major role in Title 24 compliance. In Climate Zone 1, the same statewide efficiency standards apply, but the zone's climate influences how heating and cooling are weighted in the energy model.
What Title 24 looks at for HVAC
- Equipment efficiency ratings (e.g., SEER2 / HSPF2)
- Duct sealing and insulation
- Refrigerant charge and airflow (HERS-verified where applicable)
- Heat pumps, which current code favors statewide
Title 24 is a statewide California energy code. Climate Zone 1 does not have its own separate rules — the same statewide standards apply, with the energy budget calibrated to this zone's climate. Your project's exact requirements are determined when your specific address is modeled in CEC-approved compliance software. The 2022 and 2025 standards established heat pumps as a baseline for many space- and water-heating scenarios across California.
Related: do I need a HERS rater?