The 2025 California Energy Code took effect on January 1, 2026. Every project permitted on or after that date is under the new rules. If you're used to the 2022 cycle, the 2025 cycle isn't a radical rewrite. But several things have shifted in ways that will change how you design and how your CF1R reads.
What follows is the practical list. Not an exhaustive code summary. Just the ones architects and builders have to actually account for on real projects.
Heat pumps are the prescriptive baseline
The 2025 code assumes a heat pump for both space heating and water heating in all sixteen climate zones. This is the single biggest shift from the 2022 cycle, which was heat-pump-preferred but not heat-pump-prescribed for most zones.
In practice:
- A prescriptive new-construction CF1R in any climate zone now includes a heat-pump space conditioning system and a heat-pump water heater.
- A gas furnace or a tankless gas water heater is still allowed. It is not prescriptively compliant, so it requires the performance method and a trade-off somewhere else in the model.
- Mini-split and ducted heat-pump options both work. Selection is a design decision, not a compliance decision.
If the project brief includes gas cooking or gas water heating, the performance path is mandatory. Budget time for the modeling.
Battery storage gets real compliance credit
The 2025 code is the first cycle where residential battery storage is treated as a first-class compliance measure rather than a bonus. The model can now take meaningful credit for a properly sized and controlled battery when it is paired with photovoltaic.
Two caveats worth knowing:
- The battery has to meet specific control and commissioning requirements to earn the credit. A battery wired to a generic inverter without time-of-use control does not qualify.
- The credit is visible only in performance runs. Prescriptive paths treat the battery as a nice-to-have.
For projects where the photovoltaic array can't be sized to cover the full baseline load (older roofs, shaded lots, historic districts), a battery now gives designers a legitimate compliance lever they didn't have in 2022.
Peak Cooling is a new metric
On new construction, the 2025 code introduces a Peak Cooling compliance metric. The model evaluates the house's peak summer cooling load against the baseline's peak, and the design has to meet or beat it.
Peak Cooling applies only to new construction. It does not apply to additions or alterations, which now use the LSCe-only compliance framework described below.
Why it matters: the Peak Cooling metric rewards shading, orientation, and high-performance glazing. A design with very tall south-facing glass will pass total-energy compliance but might struggle on Peak Cooling unless the glazing is specified carefully. We flag this early in our modeling if it is going to be an issue.
LSCe replaces EDR for scoring
The 2022 code used two Energy Design Rating scores (EDR1 and EDR2) that measured different things and confused almost everyone. The 2025 code consolidates them into a single metric called LSCe, Long-term System Cost efficiency.
LSCe represents the total long-term source-energy cost of operating the house, baseline-normalized. Lower numbers are better. A compliant design has an LSCe less than or equal to the baseline LSCe.
Three practical consequences:
- Alterations and additions now use an LSCe-only compliance framework. Peak Cooling is not evaluated for these projects; LSCe is the sole score.
- The old EDR-based conversations between architect and energy consultant ("what is our EDR1?") get replaced with a single LSCe number that's easier to reason about.
- Reports from the 2022 code and reports from the 2025 code are not directly comparable. An EDR of 0 is not the same as an LSCe of 0.
EnergyPro 2025 is required
The modeling software had to be updated to reflect the 2025 code. EnergyPro 2025 is the approved software for new projects permitted under the 2025 cycle. EnergyPro 2022 and earlier versions cannot produce compliant CF1Rs for 2025 projects.
A few notes:
- Old project files can be imported and re-run under the 2025 ruleset. The geometry and assemblies carry forward; the compliance calculations are re-evaluated.
- Plan-check reviewers will reject a CF1R run under the wrong software version for the permit date. This catches people doing revisions: if a project was permitted in December 2025 and revised in March 2026, the revision stays under the 2022 ruleset unless the scope change triggers re-permit.
Quality insulation installation is more widely required
QII (the field-verified insulation installation protocol) was an optional measure with compliance credit in the 2022 code. In the 2025 code, QII is required more often, especially in climate zones where the prescriptive wall assembly is thin enough that installation quality materially affects performance.
For most new construction in CZ11 through CZ16, plan on QII being required and on the rater's visit happening during rough-in, before drywall closes up the walls.
Practical advice
A few things that will make a 2025 project easier to run through compliance:
- Decide on fuel choice at schematic design. If the house wants gas cooking or gas water heating, say so early. The performance model builds around that decision, and catching it late forces re-work.
- Size the photovoltaic array against the real roof. The prescriptive PV sizing in the 2025 code is aggressive. Dialing in real available roof area, orientation, and shading at schematic keeps the compliance path from surprising you at permit.
- Budget for the rater's QII visit. If QII is in the compliance path, the insulation subcontractor needs to know it is being inspected, and the build schedule needs to hold the walls open for the rater.
- Run the CF1R against the drawings before submitting. The number-one source of plan-check corrections is a mismatch between the energy model and the drawing set. We run the check before submitting. If you are submitting your own report, do the same.
The 2025 code is aggressive in the right places. Heat pumps everywhere, meaningful battery credit, a cleaner scoring metric. It is a real code cycle, not a rename. Budget a little more time for the modeling, particularly on anything custom, and the permits go through.