Hillsborough Municipal Code Ch. 15.07 Existing Building Code

Footnotes:

--- (6) ---

Editor's note— Ord. No. 799, § 3(Exh. A), adopted December 9, 2025, in effect repealed Ch. 15.07 and enacted a new Ch. 15.07 as set out herein and as may later be amended. Former Ch. 15.07 pertained to similar subject matter and derived from Ord. No. 690, adopted December 13, 2010; Ord. No. 712, adopted November 12, 2013; Ord. No. 758, adopted November 12, 2019; Ord. No. 786, adopted November 28, 2022; and Ord. No. 788, adopted January 9, 2023.

The purpose of this chapter is to promote public safety and welfare by reducing the risk of death or injury that may result from the effects of increased demands or earthquakes on existing buildings. The provisions of this chapter are intended as minimum standards for structural vertical and lateral (seismic) force resistance, and are established primarily to reduce the risk of life loss or injury. Compliance with these provisions will not necessarily prevent loss of life or jury, or prevent earthquake damage to rehabilitated buildings.

Sections within this chapter may include both local amendments to Title 24 as adopted therein and local development standards related to construction in the town that are not part of Title 24.

(Ord. No. 799, § 3(Exh. A), 12-9-2025)

A. The rules, regulations and standards printed in the California Existing Building Code, 2025 Edition, contained in the California Building Standards Code (California Code of Regulations, Title 24 Part 10), 2025 Edition, including Appendix A, are hereby adopted as the rules, regulations, and standards for the town as to all matters contained therein except as herein otherwise provided.

B. One copy of the Existing Building Code shall at all times be kept on file at the town building department. The copy shall be accompanied by copies of this chapter (as well as any additional, subsequent amendments) to show the town amendments to the Existing Building Code.

C. In the event there is any conflict or inconsistency between the provisions of this code and the Existing Building Code when applied to any particular case, that requirement which establishes the higher degree of safety shall be complied with unless otherwise specifically stated in this code.

D. No provision of the Existing Building Code, as amended hereby, shall be deemed to supersede any other provision of this code.

(Ord. No. 799, § 3(Exh. A), 12-9-2025)

The 2025 California Existing Building Code as adopted by this chapter is hereby amended in its application to the town as set forth within Sections 15.07.040 through 15.07.080.

Any section within 15.07 that modifies the 2025 California Existing Building Code shall include the code section being changed or modified and language which describes the nature of the change or modification. Sections that do not include such reference or language are local development standards and are not amendments to Title 24.

(Ord. No. 799, § 3(Exh. A), 12-9-2025)

Section 304.3.2 is deleted in its entirety and Section 304.3.1 is amended to read as follows:

304.3.1 Structural and geotechnical evaluation, design, and retrofit triggers. In addition to the structural evaluation and retrofit requirements of the California Existing Building Code, the following local provisions shall apply:

Where, in the course of any repair, alteration, or addition to an existing structure, structural systems are or will be exposed, altered, or affected, or where such work will increase the demands on existing vertical- or lateral-force-resisting systems, the Building Official may require a structural evaluation of the affected portions of the structure.

Where work may affect foundations, bearing conditions, slope stability, or impose new loads, a geotechnical evaluation shall be provided when required by the Building Official.

Where such evaluation determines that retrofit is necessary to safeguard health, life, or safety, the retrofit shall comply with one of the following, as applicable:

1. Lateral force-resisting systems. Evaluation and design shall comply with ASCE 41 as referenced in this code. Where required by ASCE 41, a geotechnical engineer's evaluation shall be provided in support of the design. As an alternative in a scenario as permitted by the Building Official, Appendix A of the California Existing Building Code may be used when demonstrating compliance for design of the required retrofits.

2. Vertical force-resisting systems. Evaluation and design shall comply with applicable provisions of the California Building Code. Where required, a geotechnical engineer's evaluation shall be provided in support of the design. New or rehabilitated structural members and connections shall conform to current detailing requirements for new construction.

(Ord. No. 799, § 3(Exh. A), 12-9-2025)

A. When, in the judgment of the building department, it is reasonably necessary to amend the provisions of the California Existing Building Code due to local climatic, geological, topographical, or other statutorily permissible conditions, the building official shall prepare and submit the proposed amendments to the city council for consideration at the next regularly scheduled city council meeting. Before adopting any changes or modifications in the requirements contained in the provisions published in the California Existing Building Code, or in any other regulations adopted hereunder, the city council shall make an express finding that such modifications or changes are reasonably necessary because of local climatic, geological, topographical, or other statutorily permissible conditions. Such finding shall be made available as a public record. Upon approval by the city council and filing of the city council's findings with the California Building Standards Commission (CBSC) or other governing body, such amendments shall be added to and become a part of the provisions of this chapter.

B. From October 1, 2025, through June 1, 2031, the town is limited in its ability to modify provisions related to residential units. Allowable findings for modifications during this time are limited to:

1. Modifications previously adopted and filed with the CBSC before September 30, 2025;

2. Administrative changes related to administration of the code;

3. Emergency health and safety measures as deemed by the CBSC;

4. Needed to implement a greenhouse gas emissions reduction strategy as outlined in a general plan adopted before June 10, 2025; or

5. Related to fire home hardening.

(Ord. No. 799, § 3(Exh. A), 12-9-2025)

As successive editions of the California Existing Building Code are promulgated and incorporated by reference in the California Building Standards Code, the city building department, under the guidance and direction of the building official, shall review the provisions of the new code in order to determine whether they are consistent with the provisions of the California Existing Building Code then in force as modified by the provisions of this chapter. The building official shall submit a list of recommendations with respect to such changes (if any) to the city council. Upon review and adoption by the city council, according to the procedure set above, such revised version of the California Existing Building Code, together with all amendments thereto which are recommended by the building official and/or required by the provisions of this chapter, shall govern all buildings and construction within town limits.

(Ord. No. 799, § 3(Exh. A), 12-9-2025)