Title 24 requirements in Climate Zone 5 cover the same building systems as everywhere in California — what changes between zones is the energy budget, not the underlying standards.
What Title 24 covers
- Building envelope — insulation and air sealing
- Windows — U-factor and Solar Heat Gain Coefficient (SHGC)
- HVAC equipment efficiency and duct performance
- Water heating
- Lighting
- Solar PV (and battery readiness) for applicable new construction
Title 24 is a statewide California energy code. Climate Zone 5 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.
How Zone 5 affects compliance
The zone's climate sets the baseline energy budget your design is measured against, which can shift the emphasis between heating, cooling, and solar gain. The exact targets for your project come from modeling your address — see when a Title 24 report is required.