Commercial Electrical Services · Pillar Guide

Commercial lighting that pays back the install in energy savings.

LED retrofits, new commercial lighting installs, occupancy sensors, daylight harvesting — Title 24 compliant and engineered for measurable energy ROI.

Written bySteven Lockhart

Reviewed byAlex Towery · C-10 #989290

Updated: June 2026 · Read: 7 min

11 yrsMarin electrical work

C-10CSLB licensed contractor

1st passInspection rate

48 hrTypical estimate turnaround

Key Takeaways

California Title 24 Part 6 requires LED or equivalent efficacy lighting in all new commercial construction and most retrofit work — fluorescent T8 replacement is the most common Marin scope.
LED retrofit ROI typically lands in 18-36 months for commercial spaces — labor cost is the largest variable, not fixture cost.
Occupancy sensors and daylight harvesting are required by Title 24 in most commercial occupancy types — not optional add-ons.
Restaurant and retail lighting has color rendering requirements (CRI 90+ for food/merchandise display) that warehouse and office lighting don't.
PG&E and BayREN commercial energy rebates can offset 15-40% of LED retrofit costs — we coordinate the rebate paperwork.

Towery Electric — Commercial Lighting Installation.

01 — OverviewWhat Commercial Lighting Installation actually covers in Marin.

Commercial lighting work in Marin breaks into retrofit (replacing existing fluorescent or HID lighting with LED) and new install (lighting designed for new buildouts or substantial remodels). Retrofit drives most of our commercial lighting volume because the energy-savings ROI is straightforward — LED retrofits typically pay back the install in 18-36 months through reduced electricity consumption, with the post-payback energy savings continuing for the LED life (typically 50,000-80,000 hours).

What sets commercial lighting apart from residential is the regulatory framework. California Title 24 Part 6 (Building Energy Efficiency Standards) sets minimum lighting power density, requires occupancy sensors in most occupied spaces, and requires daylight harvesting in spaces near windows. CALGreen adds further requirements. Compliance isn't optional — it's gating for certificate of occupancy on new construction and for permit signoff on retrofits.

Definition

Commercial lighting work covers the design, installation, and retrofit of lighting systems in business properties — meeting California Title 24 Part 6 energy efficiency standards and CALGreen requirements for occupancy sensors and daylight harvesting.

Title 24 Part 6 essentials

Lighting power density caps (watts per square foot, varies by occupancy). Mandatory occupancy sensors in most spaces (auto-off after 20 minutes vacancy). Daylight harvesting in spaces with significant natural light (dimming based on ambient light).

Rebate coordination

PG&E commercial rebates and BayREN commercial programs offset 15-40% of qualifying LED retrofit costs. The paperwork is meaningful (pre-install audit, equipment specifications, post-install verification) and we handle it as part of project scope.

For the broader context this guide supports, see our Commercial Electrical Services overview.

Explore the Full Guide

Commercial lighting work clusters by scope (retrofit vs new), occupancy type, and rebate eligibility. This pillar links to the specific guides.

Three guides to read first

Cornerstone

LED Commercial Retrofit Process

How a typical Marin commercial LED retrofit goes — audit through rebate paperwork.

Explore the guide →

Compliance

Title 24 Part 6 Commercial Lighting

The current Title 24 requirements for commercial lighting and how to design compliant systems.

Explore → Rebate

PG&E & BayREN Commercial Rebates

How to qualify and apply for the rebates that offset LED retrofit costs.

Explore →

Browse the Full Library

By occupancy type

Technology

Controls & sensors

Compliance & rebates

02LED retrofit ROI by occupancy type.

LED retrofit payback periods vary by use pattern. High-use spaces (24/7 warehouses, long-hours retail) pay back fastest; low-use spaces (intermittent office) pay back slowest.

Occupancy type	Typical payback	Drives variance
24/7 warehouse (high bay)	12 to 24 months	Operating hours, T5HO replacement
Retail (extended hours)	18 to 30 months	Display lighting density
Restaurant	24 to 36 months	Kitchen vs dining mix
Office (standard hours)	30 to 48 months	Occupancy sensor savings
Medical office	36 to 54 months	Operating room exclusions
Hospitality	18 to 30 months	Common area continuous use

03What a Title 24 compliant lighting design includes.

Compliance with California Title 24 Part 6 isn't optional for new commercial construction or substantial retrofits. Three elements drive most of the compliance work.

Lighting power density limits

Title 24 Part 6 sets watts-per-square-foot maximums by occupancy type. Office: 0.75 W/sqft typical. Retail: 1.4 W/sqft. Restaurant: 1.6 W/sqft. Compliance requires LED-equivalent efficacy on essentially all fixtures.

Occupancy sensors (auto-off)

Most occupied spaces require occupancy sensors with auto-off after 20 minutes of vacancy. Conference rooms, offices, restrooms, storage are the most common — and the most commonly missed at design stage.

Daylight harvesting (auto-dim)

Spaces within 15 feet of windows must have lighting that auto-dims based on ambient daylight. The savings are real (20-40% lighting reduction during daylight hours) but the install adds complexity.

04PG&E and BayREN commercial rebates.

PG&E's commercial energy efficiency rebate programs offset 15-30% of qualifying LED retrofit costs for most occupancy types. BayREN (Bay Area Regional Energy Network) adds Marin-specific programs that can stack with PG&E rebates, sometimes pushing total offset to 35-40% on larger projects. The catch: rebate paperwork requires pre-install audit documentation, qualifying equipment specifications, and post-install verification — all coordinated with the rebate agency.

We handle the rebate paperwork as part of project scope on retrofits where the rebate value justifies the administrative overhead (typically projects above $15,000 in lighting scope). For smaller projects, we document the work in rebate-eligible format so the business owner can submit directly. The rebate program is meaningful for Marin commercial property owners — we've helped Marin businesses recover $4,000-$80,000 in rebates over the past few years.

05Common LED retrofit pitfalls.

Three issues we see on cheap or rushed LED retrofits.

Wrong color temperature

LEDs come in 2700K (warm), 3000K (neutral), 3500K, 4000K (cool), 5000K (daylight). Restaurants and retail want 2700-3000K for food/merchandise rendering; offices want 3500-4000K for productivity; warehouses want 4000-5000K for visibility. Wrong choice produces immediate occupant complaints.

Inadequate CRI (color rendering index)

CRI measures how accurately the light renders colors compared to natural light. Office work needs CRI 80+; food service and retail merchandise need CRI 90+. Bargain LEDs with CRI 70 look harsh and unflattering.

Frequently Asked Questions

How much does a commercial LED retrofit cost in Marin?

Pricing varies by space and fixture type. For a typical office space (10,000 sq ft, T8 fluorescent retrofit to LED), expect $18,000-$28,000 before rebates. For a high-bay warehouse retrofit (T5HO replacement with LED high-bays), expect $14,000-$22,000 per 5,000 sq ft. For restaurant retrofits with display lighting, expect $24,000-$48,000 for a typical full-service restaurant. PG&E and BayREN rebates typically offset 15-40% of these costs, which we coordinate as part of project scope.

How long do LED retrofits last?

Quality commercial LED fixtures are rated for 50,000-80,000 hours of operation, which translates to 12-20 years at typical commercial use patterns (10 hours/day, 6 days/week). After that, the LED output degrades gradually (typically to 70% of original) but doesn't fail catastrophically like fluorescent ballasts. The driver (the electronic component that regulates power to the LED) is usually the first component to need service — typically at 8-12 years for commercial-grade fixtures.

Do you handle the Title 24 compliance documentation?

Yes — Title 24 compliance documentation is included in our commercial lighting scope. For new construction and substantial retrofits, we prepare the Title 24 lighting compliance forms (CF-1R-LTI-01-E and related), coordinate with the AHJ inspector on field verification, and provide the closed-permit documentation for the certificate of occupancy submittal. The compliance documentation isn't optional for new commercial work — it's gating for CO.

Will the rebate offset the cost of better fixtures?

Usually yes — that's actually how the rebate programs are designed. PG&E and BayREN rebates pay more for higher-efficacy fixtures and for fixtures with controls (occupancy sensors, dimming). The economic logic: a $40 fixture with $15 rebate costs effectively $25; a $25 bargain fixture with no rebate costs $25 but performs worse and may not meet Title 24. The 'better fixture with rebate' path almost always wins the value comparison.

Can you do lighting design for a new restaurant?

Yes — restaurant lighting design is one of our higher-volume commercial scopes. The design considerations are specific: customer-area color temperature (2700-3000K for warmth), CRI 90+ for food rendering, kitchen-area higher color temperature (3500-4000K for visibility) with appropriate CRI, dimming control for ambiance management, and integration with the broader TI electrical scope. We work with the restaurant operator and (if applicable) the interior designer on the lighting design before pulling permit.

What's the difference between occupancy sensors and daylight harvesting?

Different functions, both required by Title 24 in most commercial spaces. Occupancy sensors detect human presence and auto-off lighting after 20 minutes of vacancy (saves energy in unoccupied spaces). Daylight harvesting senses ambient natural light and auto-dims artificial lighting when daylight is sufficient (saves energy in daylit spaces during daytime). They're complementary, not redundant — occupancy sensors save in unoccupied spaces; daylight harvesting saves in occupied-but-daylit spaces. Most Marin commercial spaces need both for Title 24 compliance.

How We Reviewed This Page

Reviewed against current California Electrical Code (Title 24, Part 3) and 2023 NFPA 70 (NEC) provisions applicable to the topic.
Pricing ranges reflect actual 2026 Towery Electric quote data from Marin County jobs — not third-party industry averages.
Permit and inspection timing reflects current AHJ practice in Novato, San Rafael, Mill Valley, and unincorporated Marin County as of mid-2026.
Technical review by Alex Towery, founder and C-10 #989290 holder, with 11+ years of California electrical work.
All factual claims about code requirements were verified against primary sources (CSLB, CARB, PG&E, AHJ) at time of publication.

References

This guide reflects Towery Electric's professional standards as a California-licensed C-10 electrical contractor and is for general information. Site conditions, panel configurations, code amendments, and permit-authority requirements vary; final scoping, sizing, and code compliance for your specific address are determined on a paid site assessment. We follow California Electrical Code (Title 24, Part 3) and applicable NFPA 70 (NEC) editions adopted by your AHJ.