If you are building a home or an addition in the Sacramento area, the HVAC design decisions you make early affect comfort and cost for decades. California’s energy code now shapes much of that design. This guide explains which code applies, what it asks of the heating and cooling system, and how to choose a contractor.
Which energy code applies
California’s 2025 Energy Code took effect on January 1, 2026, and applies to permit applications filed on or after that date. Cities confirm their own cutoff. Elk Grove, for example, says applications filed after 5 p.m. on December 30, 2025 must meet the 2025 codes. A permit filed in late 2026 will therefore follow the 2025 code, with a few exceptions the Energy Commission lists for wildfire rebuilds elsewhere in the state.
What the code asks of HVAC in a new single-family home
The California Energy Commission’s 2025 single-family compliance manual includes these items:
- Heat pump space heating. A heat pump is required for space heating in the prescriptive path in all climate zones. A builder can use the performance path instead, which balances features against each other.
- Ventilation. Mandatory mechanical ventilation, with airflow verified by a rater where the compliance path requires it.
- Duct sealing and testing. Ducts must be sealed and leakage tested, with a limit of 10 percent of airflow in total or 7 percent to the outside, or a smoke test and visual inspection as an alternative.
- Refrigerant charge verification in most climate zones.
The 2022 code, which applied to earlier permits, made a heat pump prescriptive in climate zones 3, 4, 13 and 14 and allowed other zones to choose a heat pump or gas heating. Solar panels are also required on most new homes. The solar and battery sizing rules changed in 2025, so ask your designer to confirm them for your plans.
Design comes first
ACCA sets the standards that most designers follow:
- Manual J for the heating and cooling load of the building
- Manual S for selecting equipment
- Manual D for duct design
A design done before framing is finished is much cheaper to change than ducts in a completed ceiling. Ask who is doing it and see the load calculation before equipment is ordered.
Cost benchmarks
New construction cost depends on the plans, but cost guides give a rough scale. Fixr lists about $5,800 to $14,400 for a new central air conditioner install and a wide range of $1,400 to $17,100 for ductwork, averaging near $9,300. Both guides were last updated in August 2025. For a replacement, see our new HVAC system cost guide.
Permits and inspections
The building department issues the permit and inspects the work in stages. Ask your contractor which inspections apply and who schedules them. A third-party rater must verify duct leakage, airflow and charge where the code requires it. See HVAC permits in the Sacramento area for what each city says.
Choosing the contractor
- Verify the C-20 license, bond and workers compensation on the CSLB website.
- Ask for references on similar new builds.
- Get the design, equipment models and warranty in writing.
- Ask who coordinates with the electrician and the energy rater.
Our guide on how to choose an HVAC contractor covers the license check and contract rules.
Heating and cooling options
With the 2025 code, a heat pump is the baseline for heating in the prescriptive path. Ductless systems also suit additions and accessory dwelling units. See mini-split installation in Roseville, heat pump vs furnace in Sacramento and SMUD heat pump rebates if your home is in SMUD territory.
We work with homeowners across Roseville, Rocklin, Folsom and Elk Grove. See our installation services or contact us.
Frequently asked questions
Which energy code applies to a new home permit in late 2026?
California’s 2025 Energy Code took effect on January 1, 2026 and applies to permit applications filed on or after that date. Some cities, including Elk Grove, state the cutoff in their own notices, so confirm it with your building department.
Does the 2025 code require a heat pump in new homes?
The California Energy Commission’s 2025 single-family compliance manual lists a heat pump for space heating in the prescriptive path in all climate zones. A builder can choose the performance path instead, which trades features against each other. Ask your designer which path the plans use.
Do new homes need duct testing?
Yes. The 2025 single-family compliance manual calls for ducts to be sealed and leakage tested, with a limit of 10 percent of airflow total or 7 percent to the outside, or a smoke test and visual inspection as the alternative. A third-party rater verifies it.
What should I ask an HVAC contractor on a new build?
Ask for their CSLB license number, who designs the system and does the load calculation, how the ducts will be routed and tested, which equipment they plan to use, and who handles the permit and inspections.
Is HVAC for new construction cheaper than replacement?
Not necessarily. Fixr lists about $5,800 to $14,400 for a new central air conditioner install and $1,400 to $17,100 for ductwork, with an average near $9,300, based on guides last updated in August 2025. Your cost depends on the plan, size and efficiency.