Understanding Title 24 Compliance for California Lighting Projects

The 2025 Title 24, Part 6 California Energy Code brings the most significant updates to lighting requirements in years — focusing on stricter controls, smarter integration, and reduced power density across commercial, institutional, and multi-family projects. For anyone specifying or procuring lighting in California, understanding these changes is critical to avoiding costly redesigns and compliance failures.

At BLS, we've already incorporated these requirements into our specification and compliance workflows. Here's what you need to know.

Key 2025 Title 24 Lighting Updates

1. Demand-Responsive Controls (OpenADR 2.0b)

Non-residential projects with general lighting loads of 4,000W or greater are now required to install demand-responsive controls compliant with the OpenADR 2.0b protocol. This means lighting systems must be able to receive and respond to automated demand-response signals from the utility grid — reducing power during peak demand events without manual intervention.

2. Reduced Lighting Power Densities (LPD)

The 2025 code reduces allowable lighting power densities across most space types, reflecting advancements in LED efficacy. What was compliant under the 2022 code may no longer pass. Offices, retail, and healthcare facilities see the most significant reductions, requiring specifiers to select higher-efficacy fixtures or reduce fixture counts.

For example, open office LPD allowances have dropped from approximately 0.61 W/ft² to lower thresholds that demand careful fixture selection. This is where BLS's value engineering tools become essential — our platform automatically flags specifications that exceed the new LPD limits and suggests compliant alternatives.

3. Enhanced Smart Controls Requirements

The 2025 code places stronger emphasis on intelligent lighting controls across multiple space types:

• Automatic scheduling controls are now required in more space types, ensuring lights turn off during unoccupied hours without relying on manual switches.
• Daylight responsive controls are mandatory in offices, corridors, and classrooms with access to natural light — systems must continuously dim electric lighting in response to available daylight.
• Occupancy and vacancy sensing requirements are expanded, with maximum timeout lengths specified by space type (typically 20 minutes or less).

4. Multi-Family Simplification

One welcome change: the 2025 code simplifies regulations for multi-family dwellings. Previously, projects mixing residential and non-residential spaces faced complex code interpretations about which requirements applied where. The new code clarifies these boundaries, reducing the compliance burden for mixed-use developments like our 1500 Mission project in San Francisco.

5. Outdoor Lighting Motion Sensor Requirements

Outdoor lighting now requires motion sensors that achieve 50–90% power reduction during vacancy periods. This applies to parking structures, building facades, walkways, and site lighting. The specific reduction percentage depends on the outdoor zone classification.

6. Solar and Battery Integration

Non-residential buildings must now demonstrate enhanced solar/battery integration capabilities. Lighting control systems should be designed to work in concert with on-site generation and storage, supporting the grid during peak periods and utilizing stored energy during high-rate periods.

Lighting Control Strategies That Support Compliance

Meeting Title 24 isn't just about selecting the right fixtures — it's about implementing the right control strategies. Based on guidance from the DesignLights Consortium (DLC), here are the key strategies every California project should consider:

Dimming and High-End Trim

Dimming is the foundation of energy-efficient lighting control. Over 99% of fixtures on the DLC's SSL (LED) Qualified Products List support dimming, and every Networked Lighting Control system on the NLC QPL supports it as well. High-end trim (also called task tuning) sets the maximum light output to 70–80% of full capacity — the user still perceives full brightness, but energy consumption drops significantly.

High-end trim is particularly effective in spaces that are routinely over-lit at commissioning. It's a required capability for any system listed on the DLC's NLC QPL and should be standard practice on every commercial project.

Occupancy and Vacancy Sensing

Title 24 mandates occupancy or vacancy sensing in most commercial space types. The two modes operate differently:

• Occupancy sensing (auto-on/auto-off): Lights activate automatically when motion is detected and turn off after a set timeout period.
• Vacancy sensing (manual-on/auto-off): Users must manually switch lights on, but they turn off automatically. This mode saves more energy and is required in certain space types under Title 24.

Sensor technologies include passive infrared (PIR), ultrasonic, dual-technology, microwave, and newer millimeter-wave sensors that can detect multiple occupants and even stationary presence. The choice depends on the space geometry, ceiling height, and partition layout.

Daylight Harvesting

Daylight harvesting uses photosensors to continuously dim electric lighting in response to available natural light. It's mandatory under Title 24 for spaces within 15 feet of windows or skylights. Proper commissioning is critical — poorly calibrated daylight sensors are the number one reason this strategy fails in practice.

2022 Code Requirements Still in Effect

Several 2022 Title 24 requirements remain relevant and are carried forward into the 2025 code:

• High-efficacy standards: All residential indoor and outdoor lighting must be high-efficacy and, in many cases, certified per Joint Appendix JA8.
• Indoor alterations: When 10% or more of lighting in a single space is altered, the entire space generally must comply with current code. One-for-one luminaire swaps have specific exemptions.
• Acceptance testing: Mandatory acceptance testing by certified technicians ensures controls are installed and programmed correctly. This is not optional — projects that skip acceptance testing risk failing final inspection.

How BLS Helps With Title 24 Compliance

Our platform automates Title 24 compliance verification at every stage of the lighting procurement process:

• Automated LPD checking flags any specification that exceeds allowable power density for the space type, with suggestions for compliant alternatives.
• Control strategy validation verifies that the specified control system meets occupancy sensing, daylight harvesting, and demand response requirements for each space.
• One-click compliance reports generate Title 24 documentation packages ready for plan check submission.
• JA8 verification confirms that all residential fixtures are properly certified per Joint Appendix 8 requirements.

Whether you're working on a ground-up commercial project or a tenant improvement in an existing building, BLS ensures your lighting package meets current Title 24 requirements before it goes to procurement — not after it arrives on site.