What's Required in Los Angeles
- Residential heating and cooling installations under 500,000 Btu/h, same-size AC replacements, added AC of 5 tons or less, furnaces and duct alterations are express permits with no plan check
- Fee schedule items: $24 AC compressor (25 HP or less), $19 gas furnace, $24 air handling unit, $24 add/alter/repair, $12 bathroom or kitchen vent
- Calculator totals: $65.95 for a single item, $107.91 for two or more items, with 3% and 6% surcharges included
- Homeowner mechanical permits require 12 months of residence; otherwise a CSLB C-20 HVAC contractor pulls the permit
- New circuits or service upgrades for the equipment need a separate express electrical permit
- Gas water heaters need a plumbing permit, not an HVAC permit
- Inspection requested a day ahead before 2 PM; ducts inspected before covering
- Seismic or excess-flow gas shutoff valve required on permits of $10,000 or more where the building has gas piping
- Permit expires if work has not started within six months
Do You Need a Permit to Replace an AC or Furnace in Los Angeles?
Yes. The Department of Building and Safety (LADBS) requires an HVAC permit for installing or replacing comfort heating and cooling equipment, and a like-for-like swap is not exempt. What makes it painless is that nearly every residential job is an Express Permit with no plan check: the express list covers heating and air-conditioning installations under 500,000 Btu/h, replacing A/C units with the same size and type, relocating units within the same building, adding air conditioning of 5 tons or less, gas furnaces and wall heaters under 500,000 Btu/h, duct alterations or additions in buildings without smoke control, exhaust fans of 2,000 cfm or less, and prefabricated fireplace replacements. You buy it online through PermitLA or at a counter by appointment. Repairs that replace a capacitor, motor or thermostat on an existing system are not on the permit list, and the building code's $2,500 exemption does not apply to mechanical permits. A gas water heater needs its own plumbing permit, not an HVAC permit.
Los Angeles HVAC Permits by Scenario
| What you are doing | City filing | Rule |
|---|---|---|
| Replacing the AC condenser with the same size and type | Express HVAC permit | Express item 6; $24 AC item, $65.95 total |
| Replacing the gas furnace only | Express HVAC permit | Express item 5; $19 furnace item, $65.95 total |
| Replacing furnace and AC together | Express HVAC permit | $24 + $19 items; $107.91 total |
| New heat pump split system with air handler and duct changes | Express HVAC permit | $24 AC + $24 air handler + $24 alteration; $107.91 total |
| Adding central AC to a furnace-only house (5 tons or less) | Express HVAC permit plus electrical permit for the circuit | Express HVAC item 10; electrical item 1 |
| Ductwork only | Express HVAC permit | Express item 7; $24 add/alter/repair item, $65.95 total |
| Replacing a thermostat or blower motor | None listed | Not an installation on the express list; confirm with LADBS for control changes |
How Much Does an HVAC Permit Cost in Los Angeles?
LADBS prices HVAC permits per item. The Mechanical HVAC fee schedule lists $24 for an air-conditioning compressor of 25 horsepower or less, $19 for a gas furnace, $24 for an air handling unit, $24 for an add/alter/repair item and $12 for a residential kitchen or bathroom exhaust vent, with a minimum charge when a single item is under the threshold, an issuing fee once the subtotal passes $90, and Development Services and system surcharges of 3 and 6 percent. The city's Permit Fee Calculator, which runs on the current ordinance, returns a $60.50 subtotal and $65.95 total for an AC change-out alone, the same $65.95 for a furnace alone or ductwork alone, and a $99 subtotal and $107.91 total for a furnace plus AC or for a split system with an air handler and duct alteration. There is no plan check line on an express HVAC permit. Card payments add 2.7 percent. The equipment itself is not counted at valuation the way a building permit would be; only the items are.
Who Can Pull an HVAC Permit in Los Angeles?
A C-20 HVAC contractor licensed by the CSLB, or the homeowner. LADBS allows homeowners to apply for all single-family e-permit types, including mechanical, but the owner-builder declaration you initial at issuance requires that you have lived in the home for at least 12 months before taking a mechanical permit in your own name, limits you to two structures in three years, and requires the work to be done before any sale. If the new system needs a dedicated circuit or a larger service, that is a separate express electrical permit under a C-10 license or the same homeowner rule.
Inspection
Request the inspection a day ahead, before 2 PM; regular inspections run weekdays 7 AM to 3:30 PM, and a job the inspector cannot access costs an extra trip. Keep the permit on site. Duct work is inspected before it is covered, and the final covers equipment placement, gas connection and venting. Where a permit valuation of $10,000 or more is involved, LADBS bulletin P/GI 2026-002 also requires a seismic or excess-flow gas shutoff valve on any building with fuel gas piping. Permits expire if work has not started within six months.
How to Get a HVAC Permit in Los Angeles
Match the job to the express list
Same-size AC replacement, furnace, added AC up to 5 tons, duct changes and exhaust fans are all express; nothing residential needs plan check unless it exceeds the list.
Decide who signs
Your C-20 contractor, or you as owner-builder if you have lived in the home 12 months and initial the declaration.
Buy the permit online
Apply through PermitLA listing each item: $65.95 for one item, $107.91 for furnace plus AC; 2.7 percent more by card. Add an electrical permit for any new circuit.
Install and call for inspection
Request a day ahead before 2 PM; have ducts visible before insulation or drywall covers them.
Final inspection
Equipment, gas connection, venting and any required gas shutoff valve are checked; keep the permit on site.