Energy codes are changing fast as California pushes toward big decarbonization goals. The 2025 Title 24 update leans heavily on smarter lighting controls and better submetering, treating them as practical, everyday tools for cutting energy use and giving everyone clearer insight into how buildings perform. This post walks through the major updates and highlights what designers, contractors, and facility managers can expect as they put these new requirements into practice.
Lighting the Path: How New 2025 California Title 24 Standards Transform Energy Efficiency and Building Intelligence
Lighting Control Updates
The 2025 update to California’s Title 24 lighting control standards introduces stricter requirements designed to improve energy efficiency, align with national codes, and ensure smarter building operations.
- Lower Lighting Power Densities (LPD): Office spaces reduced to 0.65 W/ft² (down from 0.75)
- Daylight & Occupancy Controls: Strengthened rules requiring automatic dimming and shut off in all daylight zones
- Multi-level or continuous dimming is required in most daylit areas
- Daylighting controls must integrated with occupancy and scheduling systems for improved energy savings
- Automatic shutoff rules are tightened so that lighting must turn off when spaces are unoccupied, time‑switch controls must operate with finer granularity and integrate with occupancy sensors, and override periods are shortened to limit unnecessary after‑hours lighting
- Removal of Tailored Method: Simplifies compliance by eliminating custom calculation pathways
Alignment with IECC/ASHRAE: Harmonization of control strategies for consistency across jurisdictions
Submetering Requirements
- Mandatory Electrical Monitoring: Building owners must track total and circuit-level electrical loads
- Data Management Systems: Required to store and analyze energy use data for compliance verification
Conclusion
2025 Title 24 sends a decisive message: advanced lighting controls and robust submetering are now fundamental to creating buildings that can stand up to future demands. The new standards cut energy waste while delivering the visibility needed for better oversight and performance tuning. Designers, owners, and operators benefit by incorporating these requirements early, positioning their projects for compliance and sustained efficiency improvements.