Why Contractors Skip HVAC Permits (and Why It Matters to You)

Most homeowners who replace an air conditioner or furnace never find out a permit was required, because the contractor never mentioned it. That silence is common, and it is rarely an accident.

I have spent more than 20 years in HVAC, on both the installation side and the inspection side. I have seen what a permitted job looks like and what an unpermitted one looks like three years later, when a buyer’s inspector or an insurance adjuster asks to see the paperwork. This post explains why so many contractors skip the permit, why they stay quiet about it, and what that costs you.

Yes, your HVAC job needs a permit

In most California jurisdictions, replacing a furnace, air conditioner, heat pump, or air handler requires a mechanical permit. So does adding or replacing ductwork, and so does installing a new ductless system. The permit is not a formality. It is what triggers an inspection by someone who does not work for the contractor.

California’s energy code (Title 24, Part 6) adds requirements on top of the local permit. When you replace equipment or ducts in an existing home, the code can call for duct leakage testing, airflow and refrigerant charge verification, and third-party field verification. Since January 1, 2026, that verification runs through the state’s Energy Code Compliance (ECC) Program, which replaced HERS for projects under the 2025 code. Those steps are tied to the permit. No permit usually means no testing and no verification.

Rules and fees vary by city and county, so the first call should be to your local building department. In Los Angeles, that means LADBS or the building department of the city you live in. A good contractor will already know the answer. For which jobs need a permit and how the process works across Los Angeles County, see our HVAC permit requirements guide.

Why contractors skip the permit, and stay quiet about it

There is no single villain here. A handful of pressures push in the same direction.

• Price competition. The permit fee, the testing, and the inspection wait all cost money. A contractor who skips them can underbid one who includes them, and the homeowner comparing two quotes rarely sees the difference.
• Speed. An unpermitted changeout can happen the day after the sale closes. A permitted job means scheduling an inspection and sometimes waiting for it.
• Fear of the inspector. An inspection exposes shortcuts: undersized ducts, a poorly sealed plenum, a wrong refrigerant charge, an improperly vented furnace. A contractor who cuts corners has a reason to avoid the person who checks.
• Paperwork and testing. Title 24 compliance takes training, equipment, and time. Some contractors would rather not do it.
• Habit. In some markets, skipping permits became normal. Contractors who learned the trade that way may never have questioned it.
• Fear of losing the sale. Some contractors worry that raising the permit adds cost and gives the customer a reason to shop around. So they say nothing and hope the homeowner never asks.

The last point is the one homeowners should notice. A contractor who does not mention the permit is making a decision for you, and it is a decision that mostly protects the contractor.

What an unpermitted job costs you

The contractor saves money. The risk lands on the homeowner, and it tends to show up later.

• Safety. Gas furnaces involve combustion, venting, and carbon monoxide. Electrical connections and refrigerant work also carry real risk. The inspection is a second set of eyes on all of it.
• Performance. Without duct testing and charge verification, an expensive new system can run poorly for years. You pay for efficiency you never get, and you may not know why your rooms are uncomfortable.
• Selling the home. California sellers must disclose known unpermitted work. Buyers’ inspectors and agents often catch it anyway. It can stall a sale, force a price cut, or require you to open up finished work to bring it into compliance.
• Insurance. If a fire or water loss is traced to unpermitted work, a claim can be disputed. Check your own policy and talk to your agent.
• Rebates and warranties. Utility rebates and some manufacturer warranties can require proof of a permit or proper commissioning. Without it, you may lose both.
• Legal exposure. The permit puts the work on the public record. Without it, you have less leverage if the contractor disappears or the work fails. In California, contractors can face licensing action for ignoring building codes, but that only helps you if someone reports it.

One point that surprises people: in many jurisdictions the homeowner, not only the contractor, is responsible for unpermitted work on their property. You can end up paying to fix a problem you did not create.

How to protect yourself before you sign

You do not need to be an expert. You need to ask a few direct questions and write down the answers.

1. “Is a permit required for this job, and who pulls it?” The contractor should pull it in their own name. Be cautious if you are asked to pull it as an “owner-builder.”
2. “Is the permit fee in the quote?” It should be a line item or clearly included.
3. “Will the work be tested and inspected?” Ask about duct leakage testing, airflow, refrigerant charge, and the final inspection.
4. “Can I have a copy of the permit and the final sign-off?” Keep both with your home records.
5. “Is your license active?” You can check any California contractor’s license on the CSLB website in about a minute.
6. Compare quotes line by line. If one bid is far below the others, find out what it leaves out.

You can also call your city or county building department yourself. Ask whether the address has an open permit and whether the job is inspected. Many departments let you search permit records online.

Already had work done and unsure whether it was permitted? A third-party inspection can tell you what was installed, how it is performing, and what, if anything, needs correcting. It is far cheaper to find out now than in the middle of a home sale, where a cost-to-cure report may be needed to price the fix.

The bottom line

A permit is not red tape added to your project. It is the one step that puts an independent inspector between you and a poorly installed system. Contractors who skip it are usually protecting their margins, not your home.

The contractors worth hiring bring up the permit before you do, include it in the price, and hand you the final sign-off when the job is done. If the person quoting your project cannot explain how the permit works, keep looking.