October 31, 2026
Replacing a Commercial Rooftop AC Unit in Los Angeles: Title 24, Permits and What to Plan For
Short answer: Replacing a commercial rooftop unit (RTU) in Los Angeles usually requires a permit, and California’s Title 24 energy standards can apply to the replacement. Depending on the equipment and building, that can mean efficiency minimums, updated controls and acceptance testing by a qualified technician. Your contractor should confirm exactly what applies to your property before quoting.
Codes and local rules change, so confirm current requirements with the building department for your address. This guide helps business owners and property managers know what to ask.
Why rooftop replacements are not a simple swap
A rooftop unit serves a lot of building: customer comfort, employee productivity, refrigerated or sensitive spaces and sometimes lease obligations. Replacing one involves structural support (the curb), electrical service, gas lines if applicable, ductwork connections, controls, crane or lift access and roof penetrations that must be properly flashed.
Where Title 24 comes in
California’s Title 24, Part 6 sets energy efficiency standards for buildings. The 2025 update took effect on January 1, 2026. When HVAC equipment in a nonresidential building is replaced, the project can trigger requirements that may include:
- Minimum efficiency for the new equipment
- Controls requirements such as thermostats and scheduling
- Economizers or other air-side features, depending on size and climate zone
- Duct sealing or testing where ducts are altered
- Acceptance testing to verify the system works as designed, often performed by a certified technician
Exact requirements depend on the system, its size and the scope of the work, so ask your contractor which apply to your project.
Permits and inspections
In the City of Los Angeles, mechanical work generally needs a permit through the Los Angeles Department of Building and Safety (LADBS), and an inspection follows. Other cities, including Burbank, Calabasas, Thousand Oaks and Pasadena, run their own building departments. For the residential version of this topic, read do you need a permit to replace your AC in Los Angeles.
Repair or replace your rooftop unit?
| Factor | Points toward repair | Points toward replacement |
|---|---|---|
| Age | Under about 10 years | Approaching or past 15 years |
| Failure type | Minor part | Compressor, heat exchanger or repeated failures |
| Refrigerant | Current type, easy to service | Phased-out refrigerant or major leaks |
| Energy bills | Stable | Rising with declining comfort |
| Downtime risk | Low | High: breakdowns affect customers or tenants |
Refrigerant is part of the decision. See new AC refrigerants R-454B and R-32 vs R-410A and the R-22 phase-out.
How to plan the project
- Get a site assessment to confirm load, curb, electrical and access.
- Ask about Title 24 and permits and who handles the paperwork and testing.
- Schedule around your business to limit downtime; after hours or weekends may be possible.
- Confirm the warranty on equipment and labor.
- Set up preventive maintenance after installation to protect your investment.
Use the same vetting questions you would for any HVAC job: 10 questions to ask an HVAC contractor, the red flags to avoid and whether to get multiple quotes. For warranties, read what warranty your HVAC system should have.
Preventive maintenance for commercial systems
Rooftop units live in the sun, wind and dust. Regular service on belts, filters, coils, economizers, refrigerant and electrical connections reduces breakdowns and extends equipment life. TOP AC offers a TOP CARE commercial program for businesses; see our commercial maintenance and tune-up services.
Frequently asked questions
Does replacing a rooftop unit require a permit?
Generally yes. Confirm with the building department for your address, and ask your contractor to handle the permit.
Does Title 24 apply to a like-for-like RTU replacement?
It can. Requirements depend on equipment size, type and scope, so ask your contractor to confirm what applies.
How long does a rooftop replacement take?
Many are done in a day or a few days, depending on size, crane access, curb and electrical work. Your contractor can give a schedule after a site visit.
Can I replace one RTU at a time?
Often yes. Phasing replacements can spread cost and limit disruption, but older units may fail at inconvenient times.
What does a maintenance plan include?
Typically scheduled inspections, filter changes, coil and belt checks and priority service. Ask for the specific scope in writing.
Commercial HVAC in Canoga Park and the Valley
TOP AC serves businesses across the San Fernando Valley and nearby cities. Explore our commercial HVAC services, commercial installation and replacement, and service areas including Canoga Park, Woodland Hills, Chatsworth, Burbank, Pasadena and more.
Planning a rooftop replacement? Request a commercial estimate or call (855) 999-8672, 24/7. TOP AC Inc., 21201 Victory Blvd, Suite 102, Canoga Park, Los Angeles, CA 91303 · CSLB #959168.