Palo Alto Municipal Code Ch. 16.17 California Energy Code, California Code of Regulations, Title 24, Part 6

Sections:

* Editor’s Note: Prior ordinance history: Ordinance 4980, 5064, 5222, 5326, 5345, 5383, 5485, 5571, and 5627.

The California Energy Code, 2025 Edition, Title 24, Part 6 of the California Code of Regulations together with those omissions, amendments, exceptions and additions thereto, is adopted and hereby incorporated in this chapter by reference and made a part hereof the same as if fully set forth herein. Except as amended herein, all requirements of the California Energy Code, 2025 Edition, Title 24, Part 6 of the California Code of Regulations shall apply.

Unless superseded and expressly repealed, references in City of Palo Alto forms, documents and regulations to the chapters and sections of the former editions of the California Code of Regulations, Title 24, shall be construed to apply to the corresponding provisions contained within the California Code of Regulations, Title 24, 2025. Ordinance No. 5627 of the City of Palo Alto and all other ordinances or parts of ordinances in conflict herewith are hereby suspended and expressly repealed.

One copy of the California Energy Code, 2025 Edition, has been filed for use and examination of the public in the Office of the Chief Building Official of the City of Palo Alto.

(Ord. 5665 § 2 (part), 2025)

The provisions of this chapter contain cross-references to the provisions of the California Energy Code, 2025 Edition, in order to facilitate reference and comparison to those provisions.

(Ord. 5665 § 2 (part), 2025)

The provisions of this chapter shall constitute local amendments to the cross-referenced provisions of the California Energy Code, 2025 Edition, and shall be deemed to replace the cross-referenced sections of said Code with the respective provisions set forth in this chapter.

(Ord. 5665 § 2 (part), 2025)

Administration and enforcement of this code shall be governed by Chapter 1, Division II of the 2025 California Building Code as amended by Palo Alto Municipal Code Chapter 16.04.

(Ord. 5665 § 2 (part), 2025)

It is unlawful for any person to violate any provision or to fail to comply with any of the requirements of this chapter or any permits, conditions, or variances granted under this chapter. Violators shall be subject to any penalty or penalties authorized by law, including but not limited to: administrative enforcement pursuant to Chapters 1.12 and 1.16 of the Palo Alto Municipal Code; and criminal enforcement pursuant to Chapter 1.08 of the Palo Alto Municipal Code. Each separate day or any portion thereof during which any violation of this chapter occurs or continues shall be deemed to constitute a separate offense.

When the chief building official determines that a violation of this chapter has occurred, the chief building official may record a notice of pendency of code violation with the Office of the County Recorder stating the address and owner of the property involved. When the violation has been corrected, the chief building official shall issue and record a release of the notice of pendency of code violation.

(Ord. 5665 § 2 (part), 2025)

(i) Single Family Building Remodel Energy Reach Code - Purpose and Intent. In addition to all requirements of the California Energy Code applicable to single-family building additions and alterations, the energy efficiency, renewable energy, and electric readiness measures specified in Sections 150.0(w) and 150.0(x) shall be required for certain single-family additions and alterations.

(j) Substantial Remodel (or “50-50-50” Rule). Any project that affects the removal or replacement of 50% or more linear length of the existing exterior walls of the building, 50% or more linear length of the existing exterior wall where the plate height is raised, or 50% or more of the existing roof framing area is removed or replaced, over a 3-year period is considered a substantial remodel.

a. Any permit(s) applied for will trigger a review of a 3-year history of the project. This review will result in determining if a substantial remodel has occurred.

b. The Chief Building Official or designee shall make the final determination regarding the application if a conflict occurs.

Section 100.1(b) of Subchapter 1 of the California Energy Code is amended by adding the following definitions:

COVERED SINGLE-FAMILY PROJECT shall mean any project in a single-family residential building originally permitted for construction before 2011 that meets any of the following criteria:

1. All residential building additions and/or alterations exceeding 1,000 square feet, as amended by this chapter and as applicable to the scope of work.

For covered single-family projects, the area of alterations will include any construction or renovation to an existing structure other than repair or addition. Alterations include raising the plate height, historic restoration, changes or rearrangements of the structural parts or elements, and changes or rearrangement of bearing walls and full height partitions.

Normal maintenance, reroofing, painting or wall papering, floor finishes, replacement-in-kind of mechanical, plumbing and electrical systems, or replacing or adding new kitchen counter and similar furniture, plumbing fixture to the building are excluded for the purposes of establishing scope of covered single-family projects.

The area of alteration should be limited to the footprint of element(s) being altered.

The sum of the footprint of the elements being altered with respect to Covered Single Family Projects, shall be calculated using the following methodology:

1. Raising the plate height: The calculation with respect to raising of the plate height will be based on the area of the footprint in which the plate height is being increased. Plate height means the vertical distance measured from the top of the finished floor to the top of the plates.

2. Historic restoration: The calculation with respect to historic restoration will be based on the area of work covered in the California Historical Building Code (Title 24, Part 8).

3. Structural parts or elements: The calculation with respect to changes or rearrangements of the structural parts or elements will be based on the sum of the individual footprints of each structural change or rearrangement. The footprint shall be calculated based on the proposed design and inclusive of any demolished structural parts or elements.

4. Bearing walls and full height partition: The calculation with respect to changes or rearrangement of walls and full height partitions will be based on the footprint of any demolished wall or full height partition and any new wall or new full height partition.

Exception: Attached and detached Accessory Dwelling Units, ADU conversions of existing structures shall meet the California Energy Code Mandatory measures only.

CERTIFIED ENERGY ANALYST is a person registered as a Certified Energy Analyst with the California Association of Building Energy Consultants as of the date of submission of a Certificate of Compliance as required under Section 10-103 of Building Energy Efficiency Standards for residential and nonresidential buildings.

ELECTRIC EQUIPMENT OR APPLIANCE means one or more devices that use electric energy to serve the needs for heating and cooling, water heating, cooking, and electric vehicle charging. In addition, ancillary equipment such as an electric panel, photovoltaic equipment, and energy storage systems that are deployed to support such devices shall be considered Electric Equipment or Appliance.

ELECTRIC HEATING APPLIANCE is a device that produces heat energy to create a warm environment by the application of electric power to resistance elements, refrigerant compressors, or dissimilar material junctions, as defined in the California Mechanical Code.

SUBSTANTIAL REMODEL (or “50-50-50”RULE). Any project that affects the removal or replacement of 50% or more linear length of the existing exterior walls of the building, 50% or more linear length of the existing exterior wall where the plate height is raised, or 50% or more of the existing roof framing area is removed or replaced, over a 3-year period is considered a substantial remodel. (Refer to Section 100.0(j)).

(Ord. 5665 § 2 (part), 2025)

Section 110.10 of Subchapter 2 of the California Energy Code is amended by adding Section 110.10 (f) to read:

(f) Existing tree canopies. In the event of a conflict between the provisions of this Code, the Solar Shade Act of 2009, and the Palo Alto Tree Ordinance (Chapter 8.10), the most protective of existing tree canopies shall prevail.

(Ord. 5681 § 2, 2025)

SECTION 120.0 NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES - MANDATORY REQUIREMENTS - GENERAL.

Section 120.0 of Subchapter 3 of the California Energy Code is amended to read:

Sections 120.1 through 120.10 establish requirements for the design and installation of building envelopes, ventilation, space-conditioning and service water-heating systems and equipment in nonresidential and hotel/motel buildings as well as covered processes that are within the scope of Section 100.0(a).

Note: The requirements of Sections 120.1 through 120.10 apply to newly constructed buildings. Section 141.0 specifies which requirements of Sections 120.1 through 120.10 also apply to additions or alterations to existing buildings. The electric readiness requirements specified in Section 120.6 (k) and Section 120.6(l) apply to substantial remodels.

(Ord. 5681 § 3, 2025)

Subchapter 3 of the California Energy Code is amended to add Section 120.6(I) to be numbered, entitled, and to read:

120.6(I) ELECTRIC READINESS REQUIREMENTS FOR SYSTEMS USING GAS OR PROPANE. Where nonresidential systems using gas or propane are installed, the construction drawings shall indicate electrical infrastructure and physical space accommodating the future installation of an electric appliance in the following ways, as certified by a registered design professional or licensed electrical contractor.

a) Branch circuit wiring, electrically isolated and designed to serve all electric heating appliances in accordance with manufacturer requirements and the California Electrical Code, including the appropriate voltage, phase, minimum amperage, and an electrical receptacle or junction box within five feet of the appliance that is accessible with no obstructions. Appropriately sized conduit may be installed in lieu of conductors; and

b) Labeling of both ends of the unused conductors or conduit shall be with “For Future Electrical Appliance”; and

c) Reserved circuit breakers in the electrical panel for each branch circuit, appropriately labeled (e.g. “Reserved for Future Electrical Appliance”), and positioned on the opposite end of the panel supply conductor connection; and

d) Connected subpanels, panelboards, switchboards, busbars, and transformers shall be sized to serve the future electric heating appliances. The electrical capacity requirements shall be adjusted for demand factors in accordance with the California Electrical Code; and

e) Physical space for future electric appliances, including equipment footprint, and if needed a pathway reserved for routing of ductwork to heat pump evaporator(s), shall be depicted on the construction drawings. The footprint necessary for future electric appliances may overlap with nonstructural partitions and with the location of currently designed combustion equipment.

(Ord. 5681 § 4, 2025)

Section 150.0 MANDATORY FEATURES AND DEVICES

Section 150.0 of Subchapter 7 of the California Energy Code is amended to read as follows (additions underlined, deletions, struck through):

Single-family residential buildings shall comply with the applicable requirements of Sections 150(a) through 150.0(vx).

NOTE: The requirements of Sections 150.0 (a) through (v) apply to newly constructed buildings and substantial remodels. Sections 150.2(a) and 150.2(b) specify which requirements of Sections 150.0(a) through 150.0(rv) also apply to additions or alterations. The electric readiness requirements of Sections 150.0 (n), (t), (u) and (v) apply to residential remodels or additions when the applicable system is included in the remodel. In addition, covered single-family projects shall also be required to comply with Section 150.0(w) and certain additions and alterations shall also be required to comply with Section 150.0(x).

Subsections 150.0 (a) - (s) are adopted without modification.

(t) Heat pump space heater ready. Systems using gas or propane furnace to serve individual dwelling units shall include the following:

1. A dedicated 240 volt branch circuit wiring shall be installed within three feet from the furnace and accessible to the furnace with no obstructions. The branch circuit conductors shall be rated at 30 amps minimum. The blank cover shall be identified as "240V ready." All electrical components shall be installed in accordance with the California Electrical Code.

2. The main electrical service panel shall have a reserved space to allow for the installation of a double pole circuit breaker for a future heat pump space heater installation. The reserved space shall be permanently marked as "For Future 240V use."

3. A designated exterior location for a future heat pump compressor unit.

Subsections 150.0 (u) - (v) are adopted without modification.

A new Subsection, (w), is added to Section 150.0 as follows:

(w) A covered single-family project shall install a set of measures based on the building vintage from the Measure Menu Table, Table 150.0-J, to achieve a total measure point score that is equal to or greater than the target score in Table 150.0-I. In addition, all mandatory measures listed in Table 150.0-J shall be installed. Measure verification shall be explicitly included as an addendum to the Certificate of Compliance to be filed pursuant to 2025 Title 24, Part 6, Section 10-103.

Installed measures shall meet the specifications in Table 150.0-K. Building vintage is the year in which the original construction permit for the building was submitted, as documented by building department records, or the permit issue date of an addition or alteration that satisfied the Performance Standards (California Energy Code, Title 24, Part 6, Section 150.1(b)) that were in effect at that time. Unless otherwise specified, the requirements shall apply to the entire dwelling unit, not just the additional or altered portion. Measures from the Measure Menu table that are to be installed to satisfy requirements under the California Energy Code, Title 24, Part 6, may not count towards compliance with these requirements. Where these requirements conflict with other California Energy Code requirements, the stricter requirements shall prevail.

Exception 1 to Section 150.0(w): Creation of a new accessory dwelling unit or junior accessory dwelling unit that is within the existing space of a single-family dwelling or accessory structure and include an expansion of not more than 150 square feet beyond the same physical dimensions as the existing accessory structure. An expansion beyond the physical dimensions of the existing accessory structure shall be limited to accommodating ingress and egress. Or, if the project would not otherwise be a covered single-family project were it not for the inclusion of an accessory dwelling unit or junior accessory dwelling unit that meets the criteria above.

Exception 2 to Section 150.0(w): Mobile homes, manufactured housing, or factory-built housing as defined in Division 13 of the California Health and Safety 12 Code (commencing with Section 17000 of the Health and Safety Code).

Exception 3 to Section 150.0(w): Emergency Housing pursuant to Appendix P of the California Building Code.

Exception 4 to Section 150.0(w): An alteration that consists solely of roof and/or fenestration projects.

Exception 5 to Section 150.0(w): If the project includes circumstances which constitute hardship or infeasibility, the applicant may request an exemption. In applying for an exemption, the burden is on the applicant to show hardship or infeasibility. Circumstances that constitute hardship or infeasibility shall include one or more of the following:

(a) That the cost of achieving compliance exceeds 20% of the valuation of cost of the project;

(b) That it is technically infeasible to achieve compliance through all packages due to conditions specific to the project;

(c) That strict compliance with these standards would create or maintain a hazardous condition(s) and present a life safety risk to the occupants.

Applicants shall follow the Infeasibility procedures in PAMC 16.17.170.

Exception 6 to Section 150.0(w): If the applicant demonstrates, using Commission-certified compliance software as specified by Section 10-109(c) and Section 10-116, that the energy budget of the proposed building design would be less than or equal to the energy budget of the building under the project if it included any set of measures that would achieve compliance under this Section 150.0(w).

Certificate of Compliance. The Certificate of Compliance shall be prepared and signed by a Certified Energy Analyst and the energy budget for the proposed design shall be no greater than the standard design building.

Exception 7 to Section 150.0(w): If the dwelling unit has previously installed measures from the Measure Menu, Table 150.0-J, and compliance can be demonstrated to the building official, then these measures shall not be required to be newly installed, and appropriate credit shall be included in the applicable compliance calculations.

Exception 8 to Section 150.0(w): A measure that is necessary for compliance is prohibited because of a covenant or other deed restriction on the property, such as a homeowners association covenant.

Exception 9 to Section 150.0(w): A covered single-family project, other than an addition, that would not otherwise be subject to this Section 150.0(w) but for installation of solar PV, solar water heating, EV charging, electrical upgrades for solar PV or EV charging, or energy storage.

Exception 10 to Section 150.0(w): The project is solely related to a repair, as defined by Title 24 Part 2 Section 202.

Exception 11 to Section 150.0(w) and 150.0(x): A covered single-family project that consists solely of medically necessary improvements or solely of seismic safety improvements.

TABLE 150.0-I: TARGET SCORES.

TABLE 150.0-J: MEASURE MENU, CLIMATE ZONE 4

TABLE 150.0-K: MEASURE SPECIFICATIONS

A new Subsection, (x), is added to Section 150.0 as follows:

(x) Electric Readiness for Alterations.

1. Electric range. Where branch circuits or receptacles are added or altered in a kitchen and the work requires a building permit, install electrical components in accordance with the California Electrical Code. The electrical components shall include either of the following:

A. A 125 volt, 20 amp electrical receptacle that is connected to the electric panel with a 120/240 volt 3 conductor branch circuit rated at 50 amps minimum, within three feet from the appliance and accessible to the appliance with no obstructions. Both ends of the unused conductor shall be labeled with the word “

B. A pathway for a future 240 volt 50 amp minimum branch circuit that shall consist of either conductors or raceway from the main electrical service panel. The main electric panel shall have space reserved to allow for the installation of a double pole circuit breaker for a future electric range installation. The reserved space shall be permanently marked as “For Future 240V use.” The raceway or conductors shall terminate at a junction box within three feet of the appliance. The blank cover shall be identified as “240V ready.”

2. Electric dryer. Where a branch circuit is added or altered within three feet of a gas or propane clothes dryer and the work requires a building permit, install electrical components in accordance with the California Electrical Code. The electrical components shall include either of the following:

A. A dedicated 125 volt, 20 amp electrical receptacle that is connected to the electric panel with a 120/240 volt 3 conductor branch circuit rated at 30 amps minimum, within three feet from the appliance and accessible to the appliance with no obstructions. Both ends of the unused conductor shall be labeled with the word “spare” and be electrically isolated. Space shall be reserved for a single pole circuit breaker in the electrical panel adjacent to the circuit breaker for the branch circuit and labeled with the words “Future Use;” or

B. A pathway for a future 240 volt 30 amp minimum branch circuit that shall consist of either conductors or raceway from the main electrical service panel. The main electric panel shall have space reserved to allow for the installation of a double pole circuit breaker for a future heat pump dryer installation. The reserved space shall be permanently marked as “For Future 240V use.” The raceway or conductors shall terminate at a junction box within three feet of the appliance. The blank cover shall be identified as “240V ready.”

3. Heat pump water heater.

A. If wall framing is removed or replaced within three feet of a gas or propane water heating appliance, space suitable for the future installation of a heat pump water heater (HPWH) shall be provided. The space shall be at least two and one-half feet by two and one-half feet wide and seven feet tall and shall include a condensate drain that is no more than two inches higher than the base of an installed water heater and allows natural draining without pump assistance or installed piping or tubing within three feet of the water heater location to a condensate drain or exterior location. If pump assistance is needed, a receptacle on a 120 volt, minimum 15 amp branch circuit for a condensate pump must be available within three feet of the water heater location.

B. Where branch circuits are altered or added within three feet of an existing gas or propane water heater or within ten feet of the designated future location of a heat pump water heater as required under Section 150.0(x)3.A, and the work requires a building permit, install electrical components in accordance with the California Electrical Code. The electrical components shall include either of the following:

i. A dedicated 125 volt, 20 amp electrical receptacle that is connected to the electric panel with a 120/240 volt 3 conductor, 10 AWG copper branch circuit rated at 30 amps minimum, within three feet from the water heater and accessible to the water heater with no obstructions. Both ends of the unused conductor shall be labeled with the word “spare” and be electrically isolated. Space shall be reserved for a single pole circuit breaker space in the electrical panel adjacent to the circuit breaker for the branch circuit and labeled with the words “Future 240V Use;” or

ii. A pathway for a future 240 volt 30 amp minimum branch circuit that shall consist of either conductors or raceway from the main electrical service panel. The main electric panel shall have space reserved to allow for the installation of a double pole circuit breaker for a future HPWH installation. The reserved space shall be permanently marked as “For Future 240V use.” The pathway shall terminate at a junction box within three feet of the appliance. The blank cover shall be identified as “240V ready”.

Exception 1 to Section 150.0(x): The project is the result of a repair as defined by Title 24 Part 2 Section 202.

Exception 2 to Section 150.0(x): If a building permit, is not otherwise required for the project other than compliance with this section.

Exception 4 to Section 150.0(x): The project is the result of a safety improvement to remove a known hazard.

Exception 5 to Section 150.0(x): Mobile homes, manufactured housing, or factory-built housing as defined in Division 13 of the California Health and Safety 12 Code (commencing with Section 17000 of the Health and Safety Code).

Exception 6 to Section 150.0(x): Emergency housing pursuant to Appendix P of the California Building Code.

Exception 7 to Section 150.0(x): Creation of a new accessory dwelling unit or junior accessory dwelling unit that is within the existing space of a single family dwelling or accessory structure and includes an expansion of not more than 150 square feet beyond the same physical dimensions as the existing accessory structure. An expansion beyond the physical dimensions of the existing accessory structure shall be limited to accommodating ingress and egress. Or, if the project would not otherwise be a covered single-family project were it not for the inclusion of an accessory dwelling unit or junior accessory dwelling unit that meets the criteria above.

(Ord. 5665 § 2 (part), 2025)

The requirements of PAMC 16.17.140 shall apply to building permit applications submitted to the city on or after January 1, 2027 and shall apply to all building permit applications submitted to the city on or after that date.

Residential Buildings – of Subchapter 9 of the 2025 California Energy Code is adopted without amendment, except as follows (additions underlined, deletions struck through):

Section 150.2(b)1C is hereby amended to read:

C. Entirely new or complete replacement space conditioning systems installed as part of an alteration, shall include all the system heating or cooling equipment, including but not limited to: condensing unit cooling or heating coil, and air handler for split systems; or complete replacement of a packaged unit; plus entirely new or replacement duct system (Section 150.2(b)1D.ii.a). Entirely new or complete replacement space-conditioning systems shall meet the requirements of Sections 150.0(h), 150.0(i), 150.0(j)1, 150.0(j)2, 150.0(m)1 through 150.0(m)10; 150.0(m)12; 150.0(m)13, 150.1(c)7, 150.2(b)1F.ii, 150.2(b)1G, and TABLE 150.2-A. Additionally, where an entirely new or complete replacement space conditioning system includes a new or replacement air-cooled air conditioner in Climate Zones 1 through 14 and 16, it shall meet the applicable requirements of Section 150.2(b)1Fiv. Where an entirely new or complete replacement space conditioning system includes a new or replacement heat pump, it shall meet the applicable requirements of Section 150.2(b)1.F.v.

Section 150.2(b)1.F. is hereby amended to read:

F. Altered space conditioning system - mechanical cooling. Alterations which install new or replacement air-cooled air conditioners shall meet the applicable requirements of subsections i and iv. Alterations which install new or replacement heat pumps shall meet the applicable requirements of subsections i, ii, iii, and v. All other alterations to refrigerant containing components such as the compressor, condensing coil, evaporator coil, refrigerant metering device, or refrigerant piping, shall meet the applicable requirements of subsections i, ii, and iii. When a space-conditioning system is an air conditioner or heat pump that is altered by the installation or replacement of refrigerant-containing system components such as the compressor, condensing coil, evaporator coil, refrigerant metering device or refrigerant piping, the altered system shall comply with the following requirements:

i. All thermostats associated with the system shall be replaced with setback thermostats meeting the requirements of Section 110.2(c).

ii. Air-cooled air conditioners in Climate Zones 2 and 8 through 15 and airsource heat pumps in all climate zones, including but not limited to ducted split systems, ducted package systems, small duct high velocity air systems, and mini-split systems, shall comply with subsections a and b, unless the system is of a type that cannot be verified using the specified procedures. Systems that cannot comply with the requirements of 150.2(b)1.F.ii shall comply with Section 150.2(b)1.F.iii.

Exception to Section 150.2(b)1.F.ii: Entirely new or complete replacement packaged systems for which the manufacturer has verified correct system refrigerant charge prior to shipment from the factory are not required to have refrigerant charge confirmed through field verification and diagnostic testing. The installer of these packaged systems shall certify on the Certificate of Installation that the packaged system was pre-charged at the factory and has not been altered in a way that would affect the charge. Ducted systems shall comply with minimum system airflow rate requirement in Section 150.2(b)1.F.ii.a, provided that the system is of a type that can be verified using the procedure specified in RA3.3 or an approved alternative in RA1.

a. Minimum system airflow rate shall comply with the applicable subsection I or II below as confirmed through field verification and diagnostic testing in accordance with the procedures specified in Reference Residential Appendix Section RA3.3 or an approved alternative procedure as specified in Section RA1.

I. Small duct high velocity systems shall demonstrate a minimum system airflow rate greater than or equal to 250 cfm per ton of nominal cooling capacity; or

II. All other air-cooled air conditioner or air-source heat pump systems shall demonstrate a minimum system airflow rate greater than or equal to 300 cfm per ton of nominal cooling capacity.

Exception 1 to Section 150.2(b)1.F.ii.a: Systems unable to comply with the minimum airflow rate requirement shall demonstrate compliance using the procedures in Section RA3.3.3.1.5; and the system's thermostat shall conform to the specifications in Section 110.12.

Exception 2 to Section 150.2(b)1.F.ii.a: Entirely new or complete replacement space conditioning systems, as specified by Section 150.2(b)1C, without zoning dampers may comply with the minimum airflow rate by meeting the applicable requirements in Tables-150.0-B or 150.0-C as confirmed by field verification and diagnostic testing in accordance with the procedures in Reference Residential Appendix Section RA3.1.4.4 and RA3.1.4.5. The design clean-filter pressure drop requirements of Section 150.0(m)12C for the system air filter device(s) shall conform to the requirements given in Tables150.0-B and 150.0-C.

b. The installer shall charge the system according to manufacturer’s specifications. Refrigerant charge shall be verified according to one of the following options, as applicable.

I. The installer and rater shall perform the standard charge verification procedure as specified in Reference Residential Appendix Section RA3.2.2, or an approved alternative procedure as specified in Section RA1; or

II. The installer shall perform the weigh-in charging procedure as specified by Reference Residential Appendix Section RA3.2.3.1 provided the system is of a type that can be verified using the RA3.2.2 standard charge verification procedure and RA3.3 airflow rate verification procedure or approved alternatives in RA1. The ECC-Rater shall verify the charge using RA3.2.2 and RA3.3 or approved alternatives in RA1.

Exception 1 to Section 150.2(b)1.F.ii.b: When the outdoor temperature is less than 55°F and the installer utilizes the weigh-in charging procedure in Reference Residential Appendix Section RA3.2.3.1 to demonstrate compliance, the installer may elect to utilize the verification procedure in Reference Residential Appendix Section RA3.2.3.2. If the verification procedure in Section RA3.2.3.2 is used for compliance, the system's thermostat shall conform to the specifications in Section 110.12. Ducted systems shall comply with the minimum system airflow rate requirements in Section 150.2(b)1.F.ii.a.

iii. Air-cooled air conditioners in Climate Zones 2 and 8 through 15 and air-source heat pumps in all climate zones, including but not limited to ducted split systems, ducted package systems, small duct high velocity, and mini-split systems, which are of a type that cannot comply with the requirements of 150.2(b)1.F.ii.b shall comply with subsections a and b, as applicable.

a. The installer shall confirm the refrigerant charge using the weigh-in charging procedure specified in Reference Residential Appendix Section RA3.2.3.1, as verified by an ECC-Rater according to the procedures specified in Reference Residential Appendix RA3.2.3.2; and

b. Systems that utilize forced air ducts shall comply with the minimum system airflow rate requirement in Section 150.2(b)1.F.ii.a provided the system is of a type that can be verified using the procedures in Section RA3.3 or an approved alternative procedure in Section RA1.

Exception to Section 150.2(b)1.F.iii: Entirely new or complete replacement packaged systems for which the manufacturer has verified correct system refrigerant charge prior to shipment from the factory are not required to have refrigerant charge confirmed through field verification and diagnostic testing. The installer of these packaged systems shall certify on the Certificate of Installation that the packaged system was pre-charged at the factory and has not been altered in a way that would affect the charge. Ducted systems shall comply with minimum system airflow rate requirement in Section 150.2(b)1.F.iii.b, provided that the system is of a type that can be verified using the procedure specified in Section RA3.3 or an approved alternative in Section RA1.

iv. New or replacement air-cooled air conditioners in Climate Zones 1 through 14 and 16 shall meet the requirements of Section 150.2(b)1Fiva or 150.2(b)1Fivb.

a. Systems with existing duct distribution systems shall meet the following requirements:

I. In all climate zones, meet the airflow and fan efficacy requirements of Section 150.0(m)13B, 150.0(m)13C, or 150.0(m)13D;

Exception 1 to Section 150.2(b)1F.iv.a.I: Single zone central forced air systems and zonally controlled central forced air systems may demonstrate compliance with an airflow greater than or equal to 300 CFM per ton of nominal cooling capacity.

II. In all climate zones, meet the refrigerant charge verification requirements of Section 150.2(b)1.F.ii; and

III. In all climate zones, vented attics shall have insulation installed to achieve a U-factor of 0.020 or insulation installed at the ceiling level shall result in an insulated thermal resistance of R-49 or greater for the insulation alone; luminaires not rated for insulation contact must be replaced or retrofitted with a fireproof cover that allows for insulation to be installed directly over the cover; and

Exception 1 to Section 150.2(b)1F.iv.a.III: Dwelling units with at least R-38 existing insulation installed at the ceiling level.

Exception 2 to Section 150.2(b)1.F.iv.a.III: Dwelling units where the alteration would directly cause the disturbance of asbestos unless the alteration is made in conjunction with asbestos abatement.

Exception 3 to Section 150.2(b)1.F.iv.a.III: Dwelling units with knob and tube wiring located in the vented attic.

Exception 4 to Section 150.2(b)1F.iv.a.III: Where the accessible space in the attic is not large enough to accommodate the required R-value, the entire accessible space shall be filled with insulation provided such installation does not violate Section 806.3 of Title 24, Part 2.5.

Exception 5 to Section 150.2(b)1F.iv.a.III: Where the attic space above the altered dwelling unit is shared with other dwelling units and the requirements of Section 150.2(b)1.F.iv.a.III are not triggered for the other dwelling units.

IV. In all climate zones, air seal all accessible areas of the ceiling plane between the attic and the conditioned space in accordance with Section 110.7.

Exception 1 to Section 150.2(b)1.F.iv.a.IV: Dwelling units with at least R-38 existing insulation installed at the ceiling level.

Exception 2 to Section 150.2(b)1.F.iv.a.IV: Dwelling units where the alteration would directly cause the disturbance of asbestos unless the alteration is made in conjunction with asbestos abatement.

Exception 3 to Section 150.2(b)1.F.iv.a.IV: Dwelling units with atmospherically vented space heating or water heating combustion appliances located inside the pressure boundary of the dwelling unit.

b. Systems with entirely new or complete replacement duct systems shall meet the following:

I. R-8 duct insulation shall be installed for all new ducts located in unconditioned space.

II. In all climate zones, meet the airflow requirements of Section 150.0(m)13B, 150.0(m)13C, or 150.0(m)13D and demonstrate an air-handling unit fan efficacy of less than or equal to 0.35 W/CFM.

III. In all climate zones, meet the refrigerant charge verification requirements of Section 150.2(b)1.F.ii.

Exception 1 to Section 150.2(b)1.F.iv: Where the capacity of the existing main electrical service panel is insufficient to supply the electrical capacity of a heat pump and where the existing main electrical service panel is sufficient to supply a new or replacement air conditioner, as calculated according to the requirements of California Electrical Code Article 220.83 or Article 220.87, systems shall comply with the applicable requirements of Sections 150.2(b)1.F.i, 150.2(b)1.F.ii, and 150.2(b)1.F.iii. Documentation of electrical load calculations in accordance with Article 220 must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.

Exception 2 to Section 150.2(b)1.F.iv: Where the required capacity of a heat pump to meet the system selection requirements of Section 150.0(h)5 is greater than or equal to 12,000 Btu/h more than the greater of the required capacity of an air conditioner to meet the design cooling load or the capacity of the existing air conditioner, systems shall comply with the applicable requirements of Sections 150.2(b)1.F.i, 150.2(b)1.F.ii, and 150.2(b)1.F.iii. Documentation of heating and cooling load calculations in accordance with 150.0(h) must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.

v. In all climate zones, heat pumps with supplementary heat, including, but not limited to, electric resistance heaters or gas furnace supplementary heating, shall comply with Section 150.0(h)7 and shall lock out supplementary heating above an outdoor air temperature of no greater than 35°F.

Section 150.2(b)2 is hereby amended to read:

2. Performance approach.

The energy budget for alterations is expressed in terms of Long-term System Cost (LSC), and the altered component(s) and any newly installed equipment serving the alteration shall meet the applicable requirements of subsections A, B, and C below.

A. The altered components shall meet the applicable requirements of Sections 110.0 through 110.9, Sections 150.0(a) through (l), Sections 150.0(m)1 through 150.0 (m)10, and Sections 150.0(p) through (q). Entirely new or complete replacement mechanical ventilation systems as these terms are used in Section 150.2(b)1L, shall comply with the requirements in Section 150.2(b)1L. Altered mechanical ventilation systems shall comply with the requirements of Section 150.2(b)1M. Entirely new or complete replacement space-conditioning systems, and entirely new or complete replacement duct systems, as these terms are used in Sections 150.2(b)1C and 150.2(b)1D.ii.a, shall comply with the requirements of Sections 150.0(m)12 and 150.0(m)13. New or replacement air-cooled air conditioners in Climate Zones 1 through 14 and 16 shall meet the applicable requirements of Section 150.2(b)1Fiv.

B. The standard design for an altered component shall be the higher efficiency of existing conditions or the requirements stated in Table 150.2-G. For components not being altered, the standard design shall be based on the existing conditions. When the third party verification option is specified as a requirement, all components proposed for alteration for which the additional credit is taken, must be verified by a certified ECC-rater.

Table 150.2-G is hereby amended to read:

Table 150.2-G Standard Design for an Altered Component

C. The proposed design shall be based on the actual values of the altered components.

(Ord. 5665 § 2 (part), 2025)

Section 160.9 of Subchapter 10 of the California Energy Code is amended to read:

Mandatory requirements for electric-ready buildings apply to newly constructed buildings and substantial remodels.

Section 160.9 Sections (a) - (f) are adopted without amendments.

(Ord. 5681 § 5, 2025)

(a) Exemption. If an applicant for a covered project believes that circumstances exist that makes it infeasible to meet the requirements of this chapter, the applicant may request an exemption as set forth below. In applying for an exemption, the burden is on the applicant to show infeasibility.

(b) Application. If an applicant for a covered project believes such circumstances exist, the applicant may apply for an exemption at the time of application submittal in accordance with the Planning and Development Services administrative guidelines. The applicant shall indicate the maximum threshold of compliance the energy compliance design professional believes is feasible for the covered project and the circumstances that make it infeasible to fully comply with this chapter. Circumstances that constitute infeasibility include, but are not limited to the following:

(1) There is conflict with the compatibility of the currently adopted California Building Standards Code;

(2) There is a lack of commercially available materials and technologies to comply with the requirements of this chapter;

(3) Applying the requirements of this chapter would effectuate an unconstitutional taking of property or otherwise have an unconstitutional application to the property.

(c) Granting of Exemption. If the Director of Planning and Development Services, or designee, determines that it is infeasible for the applicant to fully meet the requirements of this chapter based on the information provided, the Director, or designee, shall determine the maximum feasible threshold of compliance reasonably achievable for the project. The decision of the Director, or designee, shall be provided to the applicant in writing. If an exemption is granted, the applicant shall be required to comply with this chapter in all other respects and shall be required to achieve, in accordance with this chapter, the threshold of compliance determined to be achievable by the Director or designee.

(d) Denial of Exemption. If the Director of Planning and Development Services or designee determines that it is reasonably possible for the applicant to fully meet the requirements of this chapter, the request shall be denied, and the Director or designee shall so notify the applicant in writing. The project and compliance documentation shall be modified to comply with this chapter prior to further review of any pending planning or building application.

(e) Council Review of Exemption. For any covered project that requires review and action by the City Council, the Council shall act to grant or deny the exemption, based on the criteria outlined above, after recommendation by the Director of Planning and Development Services.

(Ord. 5665 § 2 (part), 2025)

(a) Any aggrieved applicant may appeal the determination of the Director of Planning and Development Services or designee regarding the granting or denial of an exemption pursuant to Section 16.17.170.

(b) Any appeal must be filed in writing with the Planning and Development Services Department not later than 14 days after the date of the determination by the Director. The appeal shall state the alleged error or reason for the appeal.

(c) The appeal shall be processed and considered by the City Council in accordance with the provisions of Section 18.77.070(f) of the City of Palo Alto Municipal Code.

(Ord. 5665 § 2 (part), 2025)