San Diego's coastal climate keeps summers milder than most of California, but "milder" still means plenty of homeowners replace an aging AC or heat pump every year. Starting January 1, 2026, that replacement runs through a meaningfully updated version of California's energy code, Title 24, and it's worth understanding before you get a quote, not after.
What Changed on January 1, 2026
California's 2025 Energy Code update took effect January 1, 2026, and any permit application submitted on or after that date has to comply with the new standards. For HVAC specifically, the update includes:
- Higher minimum efficiency: new central air conditioners and heat pumps need to meet at least 15.2 SEER2 with 7.7 HSPF2 for heat pump heating, a step up from prior minimums
- Heat pump promotion: the code is written to make heat pumps the default choice for heating and cooling in new and upgraded systems, rather than a gas furnace paired with separate AC
- Duct leakage testing required: any new HVAC installation, or a system with altered ductwork, needs independent third-party duct leakage testing
- Duct insulation minimums: ductwork and plenums need a minimum insulation value of R-8 or R-11 depending on climate zone
- Smart thermostat compatibility: new systems need to work with smart thermostats capable of receiving utility pricing signals, so a home can automatically shift energy use to cheaper rate periods
When This Actually Applies to Your Project
Title 24 isn't limited to brand-new construction. It applies to alterations and additions to existing homes too, and a specific list of remodeling activities triggers it: window replacement, HVAC upgrades, additions, and insulation changes. If your project touches any of these, the city won't issue your permit until the affected systems meet current code, not the code that applied when your house was originally built.
The trigger point is the permit application date, not when construction actually starts. A permit submitted before January 1, 2026 could generally proceed under the prior code. Anything submitted from that date forward follows the new 2025 Energy Code standards.
What Title 24 Compliance Actually Costs
Budgeting an extra $5,000 to $10,000 per single-family HVAC project for full Title 24 compliance is a reasonable starting point, though the exact number depends heavily on your specific scope:
| Compliance Item | Typical Added Cost |
|---|---|
| Heat pump water heater upgrade (net of incentives) | $2,500 to $5,000 |
| Continuous air barrier materials and labor | $1,500 to $2,500 |
| Enhanced HVAC and duct sealing | $500 to $1,000 |
| Electric-ready infrastructure | $500 to $1,000 |
| Title 24 compliance documentation | $500 to $1,000 |
Optional heat or energy recovery ventilation (HRV/ERV) systems add another $2,000 to $6,700 if you choose to include one, though they can pay for themselves over roughly 4 to 10 years through lower energy bills, commonly $1,000 to $1,250 a year, depending on system size and usage.
Testing: What Used to Be Called HERS Is Now ECC
As of January 1, 2026, the state's Home Energy Rating System (HERS) program no longer supports Title 24 compliance demonstration under that name. It's now called ECC Testing, for Energy Code Compliance, and what used to be a "HERS Rater" is now an "ECC-Rater." The actual testing work is the same, just renamed to match the updated code.
Typical costs: a standalone duct leakage test commonly runs $250 to $400 depending on property size, while a fuller ECC testing package covering multiple required inspections can run $700 to $1,500.
Are Gas Furnaces Still an Option?
The 2026 code doesn't ban gas furnaces outright, but it does add restrictions on new gas furnace installations in certain scenarios and continues to push heat pumps as the default recommended system for both heating and cooling. If you specifically want to keep a gas furnace, ask your contractor directly whether your situation qualifies and what the code requires in that case, since the answer depends on your specific project scope.
Does a Heat Pump Actually Make Sense for San Diego?
Heat pumps handle both heating and cooling from one system, which fits San Diego's climate well, mild winters that rarely need aggressive heating, and warm-but-not-extreme summers where a heat pump's cooling performance holds up fine. Since the current code is written to favor heat pumps by default, most new installations in San Diego will end up recommending one regardless, making this less of an open decision than it might be in a colder climate zone.
Getting an Accurate Quote
Title 24 compliance costs vary by home size, existing ductwork condition, and how much of your electrical infrastructure already supports a heat pump versus needing upgrades. Getting bids from more than one licensed HVAC contractor, and asking each one directly how their number accounts for 2026 code compliance, is the most reliable way to compare real numbers for your specific home.
Frequently Asked Questions
What is Title 24, and does it apply to my HVAC project?
Title 24 is California's building energy efficiency code. It applies to new construction and to alterations of existing homes, including HVAC upgrades, window replacement, additions, and insulation changes. If your project involves any of these, your permit has to demonstrate compliance with the current version of the code before it can be issued.
What are the new SEER2 and HSPF2 minimums?
Under the 2025 Energy Code, effective January 1, 2026, new central air conditioners and heat pumps generally need to meet a minimum of 15.2 SEER2 for cooling efficiency and 7.7 HSPF2 for heat pump heating efficiency.
How much extra does Title 24 compliance cost?
A reasonable budget is an additional $5,000 to $10,000 for a typical single-family HVAC project, covering items like enhanced duct sealing, air barrier work, compliance documentation, and testing. Your exact cost depends on your home's existing systems and how much needs to change to meet current code.
What is ECC testing, and how much does it cost?
ECC (Energy Code Compliance) testing is the renamed version of what was previously called HERS testing, verifying that your HVAC installation meets Title 24 requirements like duct leakage limits. A standalone duct leakage test commonly runs $250 to $400, and a fuller testing package can run $700 to $1,500.
Does replacing just my AC condenser trigger full Title 24 compliance?
Generally, yes, if it requires a permit. HVAC upgrades are specifically listed among the remodeling activities that trigger energy code compliance, so even a condenser-only replacement typically needs to meet current efficiency and testing requirements if it's permitted work. Confirm the specifics with your contractor and the local permitting office for your exact scope.
Are gas furnaces still allowed under the 2026 code?
Gas furnaces aren't banned outright, but the 2026 code adds restrictions on new gas furnace installations in certain scenarios and is written to favor heat pumps as the default system. Ask your contractor directly whether a gas furnace is an option for your specific project.
Will a heat pump actually help with San Diego's coastal climate?
Heat pumps handle both heating and cooling from a single system, which suits San Diego's mild winters and moderate summers well. Since the current code favors heat pumps by default, most new San Diego installations end up recommending one regardless of climate preference.
How do I know if my HVAC contractor's quote already includes Title 24 compliance?
Ask directly. Request an itemized bid that separately lists equipment, labor, ECC testing, and any compliance documentation, rather than one bundled number. A bid missing these items outright may look more competitive at first but can turn into a change order once your permit application is reviewed.