01An altered-cooling ordinance is not one statewide equipment rule
If you are replacing cooling equipment in an existing California home, first identify the permit’s reviewing agency, recorded application date and actual mechanical scope. Some CEC-approved local ordinances encourage air-source heat pumps while retaining an air-conditioner route with additional efficiency measures. That does not mean California has one universal local heat-pump mandate, that every replacement is treated alike or that the same supporting measures apply everywhere.
This guide uses the CEC’s Local Ordinances Exceeding the 2025 Energy Code list, checked November 6, 2026, as the sole authority for the reach-code facts below. It is a topic summary, not the complete text of every ordinance. Confirm current applicability, implementation and submission expectations with the city before selecting equipment or treating a model as final.
Title 24 contains multiple parts: Part 6 is the California Energy Code; CALGreen is Part 11 and is separate. Current residential field-verification terminology is ECC, Energy Code Compliance. HERS may remain in legacy searches and older-cycle records; changing the label does not change an existing permit’s basis or perform a required test.
CEC approved 2025 local ordinancesCEC 2025 statewide Energy CodeCEC ECC Program
02Read the building category before the equipment language
The listed local topics distinguish existing single-family homes from existing nonresidential buildings. Do not transfer a cooling rule from an office to a house or assume a residential rule applies to every multifamily property. A local addition/alteration area or valuation topic can also be separate from the cooling topic. Keep those questions distinct even when they appear under one ordinance number.
- +Palo Alto — Ordinance 5665, CEC approval January 21, 2026: existing single-family altered-cooling topic with the described heat-pump/air-conditioner alternatives. The entry also lists a separate single-family addition/alteration topic at 1,000 sq ft or more.
- +Mountain View — Ordinance 9.2025, CEC approval November 12, 2025: altered space conditioning in existing single-family homes, encouraging air-source heat pumps while allowing air conditioners with additional efficiency measures.
- +Menlo Park — Ordinance 1127, CEC approval April 27, 2026: the existing single-family altered-cooling topic, plus separate efficiency improvements for certain single-family additions/alterations valued at $100,000 or more.
- +Moreno Valley — Ordinance 1030, CEC approval August 17, 2026: altered space conditioning in existing single-family homes, encouraging air-source heat pumps while allowing air conditioners with additional efficiency measures.
- +Santa Cruz — Ordinance 2025-22, CEC approval May 26, 2026: the altered-cooling topic concerns existing nonresidential buildings. Separate Ordinance 2025-19 concerns single-family additions/alterations at 350 sq ft or more; do not merge their categories.
Palo Alto scope guideMountain View scope guideMenlo Park scope guideMoreno Valley scope guideSanta Cruz: two separate ordinances
03A five-stage decision checklist before ordering equipment
Use this sequence to turn an equipment question into a supported scope decision, without asking the modeler to invent a local interpretation.
- +1. Establish the authority and application record. Confirm which city or county reviews the parcel and obtain the recorded application date. A mailing place name, construction start, drawing date or CEC approval date does not replace that record.
- +2. Describe the existing and proposed work. Identify the building category, equipment, distribution, controls and spaces served. Distinguish a replacement from broader addition/conversion work; the word HVAC alone is not a scope description.
- +3. Confirm the local layer. Give the city that description and ask which adopted provisions apply, what options are available and what evidence is expected. Keep the answer and its date with the plans. Do not infer exemptions or precise measures from the CEC topic summary.
- +4. Compare supported options. The systems designer resolves equipment/design suitability; the energy preparer documents applicable assumptions and option consequences. Identify unresolved measures and inputs, and keep an early study provisional until the basis is confirmed.
- +5. Coordinate final documents and construction handoffs. Reconcile the equipment schedule, drawings and design records to one revision. Identify installers, qualified verification/acceptance participants and required access. A completed report is not proof of installation or a passed field test.
04What the air-conditioner alternative does—and does not—promise
The CEC summaries expressly describe air conditioners being allowed with additional efficiency measures in the listed altered-cooling topics. Do not replace that wording with an unconditional ban. Equally, do not promise that any high-efficiency air conditioner automatically satisfies the local requirement. The exact measures, exceptions and evidence for a particular application must be confirmed with the reviewing agency.
An option comparison should name the equipment input, assumed additional measures, affected drawings and unresolved questions. Do not invent a percentage improvement or energy margin to fill the table. A favorable statewide calculation can still leave a local requirement or mandatory design issue unresolved. A consultant’s report also does not determine electrical capacity, equipment sizing, duct design or installation feasibility.
05Worked scenario A: existing single-family cooling replacement
ILLUSTRATIVE ONLY — not a client case or completed compliance calculation. An owner of a 1,600 sq ft existing single-family home in Mountain View considers replacing cooling equipment. The application packet identifies the existing system, proposed heat-pump option, distribution and areas served. The 1,600 sq ft figure simply describes the fictional home; it is not a local trigger invented by this guide.
The applicant asks the City how the altered-cooling provision applies and what documentation is needed. The mechanical designer confirms supported equipment/design inputs. The energy preparer identifies the applicable design records and any unresolved assumptions. Before submission, schedules and drawings are reconciled. Required installer records and ECC verification remain separate responsibilities; choosing the heat pump is not described as completing every permit obligation.
06Worked scenario B: comparing an air conditioner with additional measures
ILLUSTRATIVE ONLY. A Menlo Park owner wants to retain an air-conditioner option during a substantial remodel. The team makes two scope rows: changed cooling and addition/alteration work with permit valuation information. It asks the City about both listed topics instead of assuming that an answer about equipment settles the valuation-based provisions.
A preliminary comparison records a heat-pump option and an air-conditioner option, the supported product inputs, any proposed additional measures and questions awaiting City/design confirmation. No invented pass/fail result is assigned. Once the basis is resolved, the owner and designers choose the coordinated scheme and the preparer produces matching output. Buying equipment before that decision can leave documentation describing something different from the plans.
07Worked scenario C: Santa Cruz nonresidential work is a different pathway
ILLUSTRATIVE ONLY. An office applicant alters existing space-conditioning equipment in Santa Cruz. The team reviews the nonresidential topic in Ordinance 2025-22, not the single-family area topic in Ordinance 2025-19. It identifies the tenant/full-building boundary, areas served and any landlord equipment, then asks the City about applicable requirements for the actual application.
The design package uses the applicable nonresidential form family and supported mechanical information. Installation certification, acceptance testing and applicable verification are identified by scope; a residential CF3R is not attached as a universal substitute. Report preparation does not perform those field tasks. The separate building category is why a house-oriented equipment checklist alone is not enough for this office.
Commercial compliance serviceNonresidential form responsibilitiesTenant-improvement checklist
08A useful question to send the reviewing city
Describe the application before asking whether a heat pump is required. For example: “Our application is recorded under this permit identifier and date. The plans show this building category, existing cooling system, equipment change and areas served. Which adopted local provisions apply to this scope, and what documentation should accompany the proposed option?” Attach the relevant plan reference so the question is not based on an equipment name alone.
Ask where to find the current public instructions and whether the response depends on details that are still missing. Keep the answer, date and unresolved items with the design record. This is a preparation template, not a claim that a particular communication establishes legal rights or replaces formal review. If applicability remains uncertain, identify it as an open decision before commissioning final output.
A second calculation cannot resolve a missing application record or an unknown local interpretation. Early modeling can still be useful when its scope and assumptions are explicitly provisional; final documentation needs the supported basis and coordinated selections. That distinction helps the owner purchase the right documentation task rather than repeatedly ordering “another Title 24” without addressing the cause of the uncertainty.
09What to send for a model, report or correction
A useful request includes the open decisions as well as the available drawings:
- +Address, reviewing agency, application history and recorded date; attach any City direction on the local layer rather than paraphrasing an old online discussion.
- +Existing/proposed plans with conditioned boundaries, addition/conversion areas and equipment service areas; identify the building category and dwelling count.
- +Supported existing/proposed equipment efficiencies, controls, distribution and designer information. Include affected window U-factor/SHGC and assemblies where relevant.
- +The prior energy package, reviewed plan set, full numbered correction comments and a change summary if work has already been submitted.
- +The requested deliverable: preliminary alternatives, coordinated permit documentation or a revision. Mark unknown inputs; do not present a product preference as a final design decision.
10Timing, roles and a practical next step
The statewide 2025 Energy Code generally applies to applications on or after January 1, 2026. Confirm the AHJ-recorded date and treatment of amendments, expired permits or refiling. CEC approval dates are not automatically local effective dates. Match software/forms to the confirmed cycle; older valid 2022-cycle records do not become 2025 documents simply because work occurs later.
Where the single-family family applies, CF1R records design compliance, installers complete applicable CF2R and qualified ECC-Raters complete required CF3R verification. Use current ECC terminology while recognizing older HERS records. Do not claim that an energy model prepares every construction-stage signature or includes a field visit.
Review published square-footage pricing and send the plans for scope review. Field testing, acceptance testing, registry fees, CALGreen and AHJ permit fees are separate. Title 24 Lab’s remote report preparation is not mechanical design, legal advice, production acceptance or a permit guarantee. The AHJ decides local applicability and submission requirements.
Application-date guideHERS to ECC terminologyCF1R service and field handoffsPricingGet a Quote and upload plans
11Six altered-cooling reach-code questions
Educational guidance, not a project-specific ordinance interpretation. Recheck official sources and confirm the actual application with the reviewing city.
Does a CEC-listed cooling ordinance ban every air conditioner?
The listed topics described here encourage air-source heat pumps while allowing air conditioners with additional efficiency measures. That is not an unconditional ban or a promise that any air conditioner qualifies. Confirm the applicable route and evidence with the city.
Does the CEC approval date decide my permit’s requirements?
Not by itself. Approval, local implementation and the recorded permit-application date are different records. Supply the application history and actual scope, then ask the AHJ about applicability before relying on an assumed date rule.
Can I use the same rule for single-family and nonresidential work?
No. The listed building categories matter. Santa Cruz Ordinance 2025-22 concerns existing nonresidential altered cooling, while several other listed topics concern existing single-family homes. Do not transfer categories, area topics or valuation provisions between projects.
Does a passing statewide model settle the local layer?
No. The calculation must use supported inputs and the correct edition, but local applicability and additional requirements still need confirmation. A preliminary model cannot waive a mandatory measure or substitute for an agency’s scope interpretation.
Should I book “HERS testing” as soon as I order a report?
First identify the code cycle, selected measures and required records. ECC is current terminology for applicable verification; HERS may remain on older-cycle records. Design preparation, installation certification and required testing are separate roles and do not automatically occur in one order package.
What should I send if equipment changed after the original report?
Send the original reviewed report/plans, proposed equipment data, affected sheets and a change summary, plus full comments if applicable. Identify the local direction being relied upon. The team must reconcile the design rather than certify an obsolete schedule.