City Council
Staff Report
From: City Manager
Report Type: CONSENT CALENDAR
Lead Department: Planning and Development Services
Meeting Date: September 8, 2025
Report #:2508-5048
TITLE
Adoption of an Emergency Ordinance Amending Palo Alto Municipal Code Chapters 16.04 (California Building Code, California Code of Regulations, Title 24, Part 2, Volumes 1 & 2), 16.05 (California Mechanical Code, California Code of Regulations, Title 24, Part 4), and 16.14 (California Green Building Standards Code, California Code of Regulations, Title 24, Part 11) to Make Non-Substantive Changes Addressing Comments from the California Building Standards Commission. CEQA Status: Exempt Pursuant to CEQA Guidelines Sections 15061(b)(3) and 15308.
RECOMMENDATION
Staff recommends that the City Council:
1. Adopt, by a four-fifths majority, the attached emergency ordinance amending Palo Alto Municipal Code (PAMC) Chapters 16.04, 16.05, and 16.14, which implement the 2022 California Building Code, California Mechanical Code and California Green Building Standards Code and local amendments, and updating associated findings.
BACKGROUND
Every three years, a new version of the California Building Standards Code (CBSC, or Title 24) is published. Local jurisdictions may enforce the model code as published or, subject to certain requirements, adopt local amendments. State law requires that ordinances amending the statewide codes be filed with and approved by the California Building Standards Commission (BSC), which reviews the amendments for compliance with state law. During the 2022 building code adoption cycle, the City Council adopted Ordinances 5564, 5565, and 5626, adopting the California Building Code, California Mechanical Code, and California Green Building Standards Code, respectively, including local amendments.
After staff filed ordinances 5564, 5565, and 5626 with the BSC, the BSC identified several minor deficiencies in those ordinances. Namely, the BSC requested that the City adopt additional findings to support several of the amendments and move some amendments to the Green
Building Standards Code from the “definitions” section to the main text of the code. The attached ordinance would cure those deficiencies without making substantive changes to the City’s adopted requirements.
Recent state law, Assembly Bill (AB) 130, limits cities’ authority to adopt local amendments to the CBSC beginning October 1, 2025, and ending June 1, 2031. Adopting this as an emergency ordinance, effective before the AB 130 moratorium begins, will allow the City to continue enforcing its local amendments to the Building Code, Mechanical Code, and Green Building Standards Code during the moratorium.
ANALYSIS
State law imposes certain requirements when local jurisdictions adopt amendments to Building Code Standards, including that the jurisdiction make express findings that each amendment is reasonably necessary because of local climatic, geological, topographic or environmental conditions.
The City of Palo Alto previously adopted local amendments to the California Building Code (CBC), California Mechanical Code (CMC), and California Green Building Standards Code (CALGreen) as part of the 2022 code cycle. These amendments addressed specific local needs, including seismic safety improvements, enhanced energy efficiency, and additional environmental protections.
Under California Health & Safety Code §§ 17958.5, 17958.7, and 18941.5, all amendments to building standards must be supported by express findings demonstrating that each change is reasonably necessary due to local climatic, geological, topographic, or environmental conditions. Administrative provisions, which are not classified as “building standards” under Health & Safety Code § 18909, do not require such findings.
During its routine review, BSC identified deficiencies in the City’s findings for certain adopted amendments. The following items require correction as proposed below:
1. California Building Code – Section 105.2, Work Exempt from Permit (Building, Item #2:
Fences and Materials)
This provision exempts work affecting certain fences and walls from permit requirements based on height and materials. The City adopted an amendment that exempted a smaller subset of these walls from permit requirements than the base codes did. The City characterized this as an administrative amendment, but the BSC requested the City adopt a local climatic, geological, or topographical finding to justify the amendment. Due to local seismic risk and soil conditions, improperly designed masonry or concrete walls can cause significant hazards in earthquakes, including injury to pedestrians and property damage.
Proposal: Leave the City’s local amendment in place and make the necessary finding that it is justified by local topographical and geological conditions.
2. California Mechanical Code – Appendix G (Sizing of Venting Systems and Outdoor Combustion and Ventilation Opening Design)
Appendix G provides example calculations for outdoor air ventilation rates in various applications. The City adopted this appendix as an administrative amendment, but the BSC requested the City adopt a local climatic, geological, or topographical finding to justify the amendment. Upon review, staff determined that adoption is unnecessary because the main body of the CMC already provides adequate requirements and calculation methods.
Proposal: Exclude Appendix G from adoption in the ordinance.
3. California Green Building Standards Code (CALGreen)
BSC requested that certain amended definitions be removed from the definitions section and codified within the substantive provisions of the code, justified by local climatic, geological, or topographical findings.
Proposal: Staff made the following revisions:
Removed definitions for “CALGreen Mandatory,” “Tier 1,” “Tier 2,” “Tier 1 & 2 Prerequisite Measures,” and “CALGreen Tier 1 & 2 Elective Measures” and replace them in a later section of the code, justified by climatic and environmental findings. Removed substantive code provisions from the definition of “Substantial Remodel” and replaced them later in the code, justified by climatic and environmental findings.
Together, these proposals will address the identified deficiencies in the prior findings and enable the City to continue to enforce these local amendments.
POLICY IMPLICATIONS
CALGreen local amendments specifically allow the City to advance its Sustainability and Climate Action Plan goals related to green building and energy efficiency. The California Building Code amendment specifically advances Safety Element goals related to natural hazard mitigation and the protection of human life and shared community assets and infrastructure. Finally, the amendment to the California Mechanical Code aligns with City efforts to simplify code language and improve overall policy accessibility and understanding among the public.
If these corrected findings are not adopted, BSC could reject the local amendments, requiring the City to revert to baseline state codes that do not reflect Palo Alto’s specific seismic, safety, and environmental needs. Adoption of this emergency ordinance before September 30, 2025, enables compliance with AB 130 and preserves the City’s ability to maintain these local amendments through the next code cycle.
FISCAL/RESOURCE IMPACT
There are not significant fiscal or resource impacts associated with the staff recommendation.
STAKEHOLDER ENGAGEMENT
These amendments clarify previously approved amendments; no additional public outreach was conducted. Notice of this item was posted at least 10 days in advance of the City Council meeting.
ENVIRONMENTAL REVIEW
This ordinance is exempt from the provisions of the California Environmental Quality Act (“CEQA”) pursuant to Section 15061(b)(3) of the CEQA Guidelines because it can be seen with certainty that there is no possibility that adopting this ordinance will have a significant effect on the environment, and Section 15308 because adopting these amendments is an action taken by the City to assure the maintenance, restoration, enhancement, or protection of the environment.
ATTACHMENTS
Attachment A: Ordinance making non-substantive changes to the California Building Code, California Mechanical Code and CALGreen
APPROVED BY:
Jonathan Lait, Planning and Development Services Director