CBC · California Building Code

What are the requirements for repairs and where are they located?

If you are repairing an existing building in California, start with § 301.2 (which directs repairs to Chapter 4) and read Chapter 4: repairs must not make the building less compliant than before, replacement materials are limited in some cases (e.g., water closets ≤1.28 gpf), glazing in hazardous locations must meet safety glazing rules, structural repairs follow Chapter 4 structural provisions (and may trigger retrofits for substantial damage), and electrical, mechanical and plumbing repairs must meet their respective California codes. file

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

Repairs to existing buildings in California must follow the standalone repair provisions in Chapter 4 of the California Existing Building Code; administratively the repair option is required by § 301.2, which states: “Repairs shall comply with the requirements of Chapter 4.” § 301.2 . Chapter 4 then establishes the scope (what counts as a repair), the baseline rule that repairs must not make the building less compliant than it was before, and specific requirements for building elements (glazing, structural repairs, fire and egress, mechanical, electrical and plumbing) that apply when repairing those systems (§§ 401–408) .

Requirements in detail

High‑level rule

  • The fundamental constraints for repairs are:
    • The work must comply with Chapter 4 (administrative trigger: § 301.2) .
    • The repair must not make the existing building “less complying than it was before the repair” (§ 401.2) .

Key decision dimensions (quick reference table)

Decision question Typical values / test Code reference
Is the work governed as a “repair”? If the work is repair work to existing building elements, Chapter 4 applies; repairs are handled independently of the alteration compliance methods (§ 301.2 / Chapter 4) § 301.2; Chapter 4
May you use “like” materials? Like materials are permitted for repairs provided they do not create a hazard; new/replacement materials must meet requirements for new work where Chapter 4 requires (§ 402.3; § 302 references) § 402.3; § 302 (general provisions)
Does the repair change level of egress/fire protection? Repairs must maintain the existing level of means of egress and fire protection (§§ 404.1, 403.1) § 404.1; § 403.1
Structural repairs standard Structural repairs must follow Chapter 4 structural rules; concrete repair may be permitted to meet ACI 562 Section 1.7 where allowed (§ 405.1.1) § 405.1; § 405.1.1
Substantial structural damage / retrofit triggers Where damage is “substantial,” Chapter 4 requires evaluation and retrofitting to applicable CBC structural provisions (references to § 1612 for flood areas and other retrofit triggers) (§ 405.2 series) § 405.2 (and cross‑references to § 1612)
Replacement glazing in hazardous locations Replacement glazing in hazardous locations must comply with safety glazing requirements for new work (exceptions narrow) (§ 402.1) § 402.1
Electrical, mechanical, plumbing repairs Repairs to electrical, mechanical and plumbing must comply with the respective California codes; plumbing fixture replacements may be limited (e.g., water closets) (§§ 406.1, 407.1, 408.1–408.2) § 406.1; § 407.1; § 408.1–408.2
Flood hazard special rule Repairs that are “substantial improvement” (or substantial damage repair) in flood hazard areas must bring the building into compliance with the applicable CBC flood provisions (§ 401.3 and cross‑refs to § 1612) § 401.3; § 1612 cross‑reference

Expanded detail (selected topics)

  • Scope and primary rule: Chapter 4 is the code chapter that governs all repairs. The administrative direction that repairs use Chapter 4 is set by § 301.2; Chapter 4 then defines scope, allowable materials and the “no less complying” rule (§ 401.1–401.2) .
  • Materials and glazing: Replacement glazing in hazardous locations must meet the safety glazing requirements of the CBC/CRC unless explicitly excepted. New/replacement materials used for repairs must meet the requirements the code imposes for replacement work where Chapter 4 so requires (§ 402.1, § 402.3) .
  • Fire and egress: Repairs must preserve the level of fire protection and egress that existed prior to the repair; you cannot reduce the established level of protection as a result of repair work (§§ 403.1, 404.1) .
  • Structural repairs and substantial damage: Structural damage repairs are governed by § 405. Structural concrete repair may be done using ACI 562 Section 1.7 where allowed (§ 405.1.1). If components have sustained “substantial structural damage,” Chapter 4 requires evaluation and (where noncompliant) retrofit to applicable structural provisions and potentially to CBC load provisions or to flood or seismic retrofit rules (§ 405.2 series) .
  • Building systems: Repairs to electrical, mechanical and plumbing systems must comply with the California Electrical, Mechanical and Plumbing Codes respectively; Chapter 4 points users to those codes for repair work (§§ 406.1, 407.1, 408.1) .
  • Conservation / fixture limits: Some repair activities are constrained by efficiency or equipment limits—for example, the code caps maximum water consumption for replaced water closets at 1.28 gallons per flush (§ 408.2) .

Exceptions & special cases

  • Historic buildings: Repairs to historic buildings have tailored provisions; the CEBC points to Title 24, Part 8 (California Code of Regulations) and other OSHPD adoptions for historic building repair requirements (§ 401.1) .
  • Bleachers / grandstands: Repairs to bleachers, folding and telescopic seating and grandstands must follow ICC 300 rather than ordinary Chapter 4 provisions (§ 401.1.1) .
  • State‑owned and OSHPD‑regulated facilities: For certain state‑owned buildings and facilities regulated by OSHPD or other state agencies, Chapter 4 may be modified or replaced by other sections (references to Sections 317–322 or Chapter 4A for OSHPD) — check the CEBC adoption matrix and Chapter 1 cross‑references before applying Chapter 4 verbatim (§ 401.1.2 and Chapter 4A) .
  • Routine maintenance vs. repairs: Routine maintenance or ordinary repairs that are exempt from permit per CBC Section 105.2 (or similar local rules) may not trigger the repair provisions; where Chapter 4 excludes routine maintenance it is stated (see Chapter 4A exceptions language) .
  • Flood hazard areas: Repairs that qualify as a “substantial improvement” or repair of substantial damage in flood hazard areas are subject to the CBC flood provisions (see § 401.3 and cross‑ref to § 1612) — local code official determinations apply for substantial improvement status (§ 401.3; § 104 administrative guidance on flood hazard determinations) .

Common mistakes

  • Treating every replacement as a “like‑for‑like” repair: Chapter 4 allows like materials in some cases, but replacement materials can be required to meet current performance limits (example: water closets) — check §§ 402.3 and 408.2 before assuming permissive substitution .
  • Ignoring the “no less complying” rule: Owners or contractors sometimes reduce egress/fire features (for example, remove emergency lighting or reduce stair width) during repairs — Chapter 4 forbids making the building less complying than before (§ 401.2) .
  • Overlooking cross‑code requirements for systems: Repairs to electrical, mechanical or plumbing must comply with their respective California codes — do not rely only on Chapter 4 language; check the CEC, CMC and CPC references triggered by §§ 406–408 .
  • Assuming flood or seismic retrofit is never required: Substantial damage or substantial improvement in flood zones or where structural damage occurred from seismic/wind may trigger upgrades; the code cross‑references these retrofit provisions (§ 405.2 series; § 401.3) .
  • Using wrong authority for special buildings: OSHPD, DSA and other agencies adopt modified sections — verify whether Chapter 4 or Chapter 4A (or other sections) apply to your building type before relying on standard Chapter 4 text .

Worked example — replacing a toilet and a hazardous glass panel (concrete, plumbing & glazing)

Scenario: A retail owner repairs two damaged toilet fixtures and replaces a cracked glass panel in a display window that is located in a hazardous location next to a circulation path.

Step 1 — Plumbing replacement rule:

  • The code limits maximum water consumption for replaced water closets to 1.28 gallons per flush. Therefore any replacement toilets must be certified at or below 1.28 gpf (§ 408.2) .

Step 2 — Glazing replacement rule:

  • The cracked glass is in a hazardous location. Replacement glazing in hazardous locations must meet the safety glazing requirements of the CBC (i.e., replace with an approved safety glazing product or assembly) (§ 402.1) .

Step 3 — Confirm “no less complying” and permits:

  • Confirm that replacing the fixtures and glazing will not reduce fire or egress protection or otherwise make the building less complying than before the repair; if the repair work requires a permit or brings other systems into scope (electrical or structural work at the countertop or framing), follow the respective code cross‑references (§ 401.2; §§ 403.1–404.1; §§ 406–408) .

Result: Purchase toilets rated ≤1.28 gpf and safety glazing certified for hazardous locations; obtain permits if local rules or the scope of work (for example, alterations to structural framing or electrical work) require them; document compliance on the permit drawings and in the inspection process (§§ 301.2; 402.1; 408.2) .

Related provisions

  • § 301.2 — Repairs shall comply with the requirements of Chapter 4 (administrative trigger)
  • § 401.1 — Scope: repairs must comply with Chapter 4; historic building cross‑references to Title 24 Part 8/OSHPD where applicable
  • § 401.2 — Compliance: work shall not make the building less complying than it was before the repair
  • § 401.3 — Flood hazard area provisions for repairs that constitute substantial improvement
  • § 402.1 — Replacement glazing in hazardous locations must meet safety glazing requirements
  • § 402.3 — New/replacement materials used for repairs (materials requirement)
  • § 403.1 — Repairs must maintain fire protection level
  • § 404.1 — Repairs must maintain means of egress protection
  • § 405.1 / § 405.1.1 — Structural repairs; ACI 562 allowed for concrete repair where applicable
  • § 405.2 (series) — Substantial structural damage and retrofit triggers; cross‑references to CBC load and flood provisions (§ 1612)
  • § 406.1 — Electrical repairs must comply with California Electrical Code (CEC)
  • § 407.1 — Mechanical repairs must comply with California Mechanical Code (CMC)
  • § 408.1–408.2 — Plumbing materials and water closet replacement limit (1.28 gpf)

Code references

Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:

  • CBC § 401.1 High relevance — show source text

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    4 REPAIRS

    User notes:

    About this chapter: Chapter 4 provides requirements for repairs of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.

    SECTION 401—GENERAL

    401.1 Scope. R epairs shall comply with the requirements of this chapter. Repairs to historic buildings and structures shall comply with Part 8, Title 24, C.C.R. [OSHPD 1R, 2, 4 & 5] Repairs to historic buildings not adopted by OSHPD. Repairs shall comply with the requirements in the California Building Code, Sections 1224.2, 1225.2, 1226.2, 1227.2 and 1228.2 for functional requirements as applicable.

    401.1.1 Bleachers, folding and telescopic seating and grandstands. Repairs to existing bleachers, folding and telescopic seating and grandstands shall comply with ICC 300.

    401.1.2 Scope. [BSC] For state-owned buildings, including those owned by the University of California and the California State University and the Judicial Council, the requirements of Sections 405.2.1 and 405.2.3 are replaced by the requirements of Sections 317 through 322.

    401.2 Compliance. The work shall not make the building less complying than it was before the repair was undertaken. Work on nondamaged components that is necessary for the required repair of damaged components shall be considered part of the repair and shall not be subject to requirements for alterations.

    [BS] 401.3 Flood hazard areas. In flood hazard areas, repairs that constitute substantial improvement shall require that the building comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable.

    SECTION 402—BUILDING ELEMENTS AND MATERIALS

    402.1 Glazing in hazardous locations. Replacement glazing in hazardous locations shall comply with the safety glazing requirements of the California Building Code or California Residential Code as applicable.

    Exception: Glass block walls, louvered windows and jalousies repaired with like materials.

    402.2 Existing materials. [HCD] Existing materials shall comply with Section 302.3.

    402.3 New and replacement materials. [HCD & HCD 2] New and replacement materials used for repairs shall comply with Section 302.4.

    SECTION 403—FIRE PROTECTION

    403.1 General. Repairs shall be done in a manner that maintains the level of fire protection provided.

    SECTION 404—MEANS OF EGRESS

    404.1 General. Repairs shall be done in a manner that maintains the level of protection provided for the means of egress.

    SECTION 405—STRUCTURAL

    [BS] 405.1 General. Structural damage shall be repaired in compliance with this section and Section 401.2.

    405.1.1 Structural concrete. Repair of structural concrete shall be permitted to comply with ACI 562 Section 1.7, except where Section 405.2.2, 405.2.3 or 405.2.4.1 requires compliance with Section 304.3.

  • CBC § 1.2 High relevance — show source text

    1.2_|X|||||||||||||||||||||||| |401.2|||X|||||||||||||||||||||| |401.3|X|||||||||||||||||||||||| |402|||X|||||||||||||||||||||| |402.2||||X|X|||||||||||||||||||| |402.3||||X|X|||||||||||||||||||| |403|||X|||||||||||||||||||||| |404|||X|||||||||||||||||||||| |405.2.1 – 405.2.5||||†|†|||||||||||||||||||| |405.2.3.1|||X|||||||||||||||||||||| |405.2.6|X|||||||||||||||||||||||| |406|||X||||||||†|†||†|†|||||||||| |406.1|X|||||||||||||||||||||||| |407.1|X||X|X|X|||||||||||||||||||| |408|||X|||||||||||||||||||||| |408.1|X|X||X|X|||||||||||||||||||| |408.2|X|X||X|X|||||||||||||||||||| |408.3||||†|†||||||||||||||||||||

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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    4 REPAIRS

    User notes:

    About this chapter: Chapter 4 provides requirements for repairs of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.

    SECTION 401—GENERAL

    401.1 Scope. R epairs shall comply with the requirements of this chapter. Repairs to historic buildings and structures shall comply with Part 8, Title 24, C.C.R. [OSHPD 1R, 2, 4 & 5] Repairs to historic buildings not adopted by OSHPD. Repairs shall comply with the requirements in the California Building Code, Sections 1224.2, 1225.2, 1226.2, 1227.2 and 1228.2 for functional requirements as applicable.

    401.1.1 Bleachers, folding and telescopic seating and grandstands. Repairs to existing bleachers, folding and telescopic seating and grandstands shall comply with ICC 300.

    401.1.2 Scope. [BSC] For state-owned buildings, including those owned by the University of California and the California State University and the Judicial Council, the requirements of Sections 405.2.1 and 405.2.3 are replaced by the requirements of Sections 317 through 322.

    401.2 Compliance. The work shall not make the building less complying than it was before the repair was undertaken. Work on nondamaged components that is necessary for the required repair of damaged components shall be considered part of the repair and shall not be subject to requirements for alterations.

  • CBC § 1.10.1 High relevance — show source text

    **_ The provisions of adopted sections in Chapters 3 through 5 shall control the alteration, repair and change of occupancy or function of existing structures for applications listed in Section 1.10.1, 1.10.2, 1.10.4 and 1.10.5 regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD). Functional service spaces shall comply with the requirements in the California Building Code, Sections 1224, 1225, 1226, 1227 and 1228.

    301.1.1 Bleachers, folding and telescopic seating and grandstands. Existing bleachers, folding and telescopic seating and grandstands shall comply with ICC 300.

    301.2 Repairs. Repairs shall comply with the requirements of Chapter 4.

    301.3 Alteration, addition or change of occupancy. The alteration, addition or change of occupancy of all existing buildings shall comply with one of the methods listed in Section 301.3.1, 301.3.2 or 301.3.3 as selected by the applicant. Sections 301.3.1 through 301.3.3 shall not be applied in combination with each other. [OSHPD 1R, 2, 4 and 5] Sections 301.3.2 and 301.3.3, not adopted by OSHPD.

    Exception: Subject to the approval of the code official, alterations complying with the laws in existence at the time the building or the affected portion of the building was built shall be considered in compliance with the provisions of this code. New structural

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    PROVISIONS FOR ALL COMPLIANCE METHODS

    members added as part of the alteration shall comply with the California Building Code . This exception shall not apply to the following:

    1. Alterations for accessibility required by the California Building Code, Chapter 11A.

    2. Alterations that constitute substantial improvement in flood hazard areas, which shall comply with Sections 503.2, 701.3 or 1303.1.3.

    3. Structural provisions of Section 304, Chapter 5 or to the structural provisions of Sections 706, 805 and 906.

    301.3.1 Prescriptive compliance. Alterations, additions and changes of occupancy complying with Chapter 5 of this code in buildings complying with the California Fire Code shall be considered in compliance with the provisions of this code.

    Exception: Hospital buildings removed from acute care service, skilled nursing facilities, intermediate-care facilities, correctional treatment centers and acute psychiatric hospitals [OSHPD 1R, 2, 4 and 5]. The provisions of adopted sections in Chapters 3 through 5 shall control the alteration, repair and change of occupancy or function of existing structures for applications listed in Section 1.10.1, 1.10.2, 1.10.4 and 1.10.5 regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD). Refer to Chapter 3A for services, systems and utilities that serve OSHPD 1 buildings.

  • CBC § 1.10.1 Medium relevance — show source text
    CHAPTER TOPICS Col2
    CHAPTER SUBJECTS
    1, 2 Administrative Requirements and Definitions
    3 Provisions for all Compliance Methods
    4 Repairs
    5 Prescriptive Compliance Method for Existing Buildings
    6–11 Work Area Compliance Method for Existing Buildings
    13 Performance Compliance Method for Existing Buildings
    14 Relocated Buildings
    15 Construction Safeguards
    16 Referenced Standards
    Appendix A Guidelines for Seismic Retrofit of Existing Buildings
    Appendix B Supplementary Accessibility Requirements for Existing Buildings
    Appendix C Guidelines for Wind Retrofit of Existing Buildings
    Appendix D Board of Appeals
    Appendix E Temporary Emergency Uses
    Resource A Guidelines on Fire Ratings of Archaic Materials and Assemblies

    CALIFORNIA BUILDING CODE CORRELATED TOPICS

    The CEBC requirements for construction safeguards are directly correlated to the requirements of the CBC. The following table shows chapters of the CBC that are correlated with the CEBC:

    CEBC/CBC CORRELATED TOPICS Col2 Col3
    CEBC CHAPTER/SECTION CBC CHAPTER/SECTION SUBJECT
    Chapter 15 Chapter 33 Construction safeguards

    Chapter 1 Scope and Administration.

    Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.

    Chapter 2 Definitions.

    Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.

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    Chapter 3 Provisions for All Compliance Methods.

    Chapter 3 guides the use of the three compliance methods of the CEBC and provides requirements that apply globally. The globally applicable requirement include general requirements related to buildings materials and other applicable codes, storm shelters, structural loads, in-situ load tests, accessibility, smoke alarms, carbon monoxide detection and exterior wall coverings.

    Chapter 3A Provisions for All Compliance Methods.

    Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).

    Chapter 4 Repairs.

    Chapter 4, a chapter independent of the three compliance methods, governs the repair of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.

    Chapter 4A Repairs.

    Chapter 4A governs the repair of existing buildings regulated by the Department of Health Care Access and Information/Office of State- wide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).

  • CBC § 1.11. Medium relevance — show source text

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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    4 A REPAIRS

    User notes:

    About this chapter: Chapter 4A governs the repair of existing buildings regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers [applications listed in Section 1.10.1 (OSHPD 1)].

    SECTION 401 A —GENERAL

    401 A .1 Scope. Repairs shall comply with the requirements of this chapter. The provisions of this chapter shall apply to existing structures for applications listed in Section 1.10.1 [OSHPD 1] regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).

    401 A .1.1 Bleachers, folding and telescopic seating and grandstands. Repairs to existing bleachers, folding and telescopic seating and grandstands shall comply with ICC 300.

    401 A .2 Compliance. The work shall not make the building less complying than it was before the repair was undertaken. Work on nondamaged components that is necessary for the required repair of damaged components shall be considered part of the repair and shall not be subject to requirements for alterations.

    401 A .3 Flood hazard areas. In flood hazard areas, repairs that constitute substantial improvement shall require that the building comply with Section 1612 A of the California Building Code .

    SECTION 402 A —BUILDING ELEMENTS AND MATERIALS

    402 A .1 Glass replacement. The installation or replacement of glass shall be as required for new installations in accordance with the California Building Code.

    SECTION 403 A —FIRE PROTECTION

    403 A .1 General. Fire protection shall comply with the California Building Standards Code.

    SECTION 404 A —MEANS OF EGRESS

    404 A .1 General. Repairs shall be done in a manner that maintains the level of protection provided for the means of egress.

    SECTION 405 A —STRUCTURAL

    405 A .1 General. Structural damage shall be repaired in compliance with this section and Section 401 A .2.

    Exception: Routine maintenance required by Chapter 3A, ordinary repairs exempt from permit in accordance with California Building Code Section 105.2, and abatement of wear due to normal service conditions shall not be subject to the requirements for repairs in this section.

  • CBC § 309.2.1 Medium relevance — show source text

    2||||X|X|||||||||||||||||||| |309.2.1|||X|||||||||||||||||||||| |310 – 311|||||||||||X|X|||X|||||||||| |312|||||||||||X|||||||||||||| |313 – 316|||X|||||||||||||||||||||| |317 – 322|X|||||||X|X|||||||||||||||| |323||||||||X|X||||||||||||||||

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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    3 PROVISIONS FOR ALL COMPLIANCE METHODS

    User notes:

    About this chapter: Chapter 3 explains the three compliance options for alterations and additions available in the code. In addition, this chapter also lays out the methods to be used for seismic design and evaluation throughout this code. Finally, this chapter clarifies that provisions in other I-Codes related to repairs, alterations, additions, relocation and changes of occupancy must also be addressed unless they conflict with this code. In that case, this code takes precedence.

    SECTION 301—ADMINISTRATION

    301.1 Applicability. The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with Section 301.2, 301.3 or 301.4. The provisions of Sections 302 through 309 shall apply to all alterations, repairs, additions, relocation of structures and changes of occupancy regardless of compliance method. [OSHPD 1R, 2, 4 and 5] Section 301.4 not permitted by OSHPD.

    Exceptions: 1. Existing state-owned structures. [BSC] The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with the provisions of Sections 317 through 322 as the minimum standards for earthquake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University or the Judicial Council. The provisions of Sections 317 through 322 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings. 2. Public school buildings [DSA-SS] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as public school buildings under the jurisdiction of the Division of the State Architect—Structural Safety (DSA-SS, refer to Section 1.9.2.1) where required by Sections 4-307 and 4-309(c) of the California Administrative Code. The provisions of Sections 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public school buildings currently under the jurisdiction of DSA-SS. 3. _**Community college buildings.

  • CBC § 1.10.1 Medium relevance — show source text

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    Chapter 3 Provisions for All Compliance Methods.

    Chapter 3 guides the use of the three compliance methods of the CEBC and provides requirements that apply globally. The globally applicable requirement include general requirements related to buildings materials and other applicable codes, storm shelters, structural loads, in-situ load tests, accessibility, smoke alarms, carbon monoxide detection and exterior wall coverings.

    Chapter 3A Provisions for All Compliance Methods.

    Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).

    Chapter 4 Repairs.

    Chapter 4, a chapter independent of the three compliance methods, governs the repair of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.

    Chapter 4A Repairs.

    Chapter 4A governs the repair of existing buildings regulated by the Department of Health Care Access and Information/Office of State- wide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).

    Chapter 5 Prescriptive Compliance Method.

    Chapter 5 provides one of the three main options of compliance available in the CEBC for buildings and structures undergoing alteration, addition or change of occupancy. The base requirements are more administrative in nature. The structural triggers for upgrades are consistent with the Work Area Method.

    Chapter 5A Prescriptive Compliance Method.

    Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).

    Chapter 6 Classification of Work.

    Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.

    Chapter 7 Alterations—Level 1.

    Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.

    Chapter 8 Alterations—Level 2.

    A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.

    Chapter 9 Alterations—Level 3.

  • CBC § 104.2.4.1 Medium relevance — show source text

    [A] 104.2.4.1 Flood hazard areas. For existing buildings located in flood hazard areas for which repairs, alterations and additions constitute substantial improvement, the code official shall not grant modifications to provisions related to flood resistance unless a determination is made that:

    1. The applicant has presented good and sufficient cause that the unique characteristics of the size, configuration or topography of the site render compliance with the flood-resistant construction provisions inappropriate.

    2. Failure to grant the modification would result in exceptional hardship.

    3. The granting of the modification will not result in increased flood heights, additional threats to public safety or extraordinary public expense; create nuisances; cause fraud on or victimization of the public; or conflict with existing laws or ordinances.

    4. The modification is the minimum necessary to afford relief, considering the flood hazard.

    5. A written notice will be provided to the applicant specifying, if applicable, the difference between the design flood elevation and the elevation to which the building is to be built, stating that the cost of flood insurance will be

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    ADMINISTRATION

    commensurate with the increased risk resulting from the reduced floor elevation and that construction below the design flood elevation increases risks to life and property.

    [A] 104.3 Applications and permits. The code official shall receive applications, review construction documents, issue permits, inspect the premises for which such permits have been issued and enforce compliance with the provisions of this code.

    [A] 104.3.1 Determination of substantially improved or substantially damaged existing buildings and structures in flood hazard areas. For applications for reconstruction, rehabilitation, repair, alteration, addition or other improvement of existing buildings or structures located in flood hazard areas, the code official shall determine where the proposed work constitutes substantial improvement or repair of substantial damage. Where the code official determines that the proposed work constitutes substantial improvement or repair of substantial damage, and where required by this code, the code official shall require the building to meet the requirements of Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable.

    [A] 104.3.2 Preliminary meeting. When requested by the permit applicant or the code official, the code official shall meet with the permit applicant prior to the application for a construction permit to discuss plans for the proposed work or change of occupancy in order to establish the specific applicability of the provisions of this code.

    Exception: Repairs and Level 1 alterations.

    [A] 104.3.3 Building evaluation. The code official is authorized to require an existing building to be investigated and evaluated by a registered design professional based on the circumstances agreed on at the preliminary meeting. The design professional shall notify the code official if any potential noncompliance with the provisions of this code is identified.

    [A] 104.4 Right of entry. Where it is necessary to make an inspection to enforce the provisions of this code, or where the code official has reasonable cause to believe that there exists in a structure or on any premises a condition that is contrary to or in violation of this code that makes the structure or premises unsafe, dangerous or hazardous, the code official is authorized to enter the structure or premises at all reasonable times to inspect or to perform the duties imposed by this code. If such structure or premises is occupied, the code official shall present credentials to the occupant and request entry.

  • CBC § 2-16 Medium relevance — show source text

    Stud to top or bottom plate|2-16d common (31/2″ × 0.162″); or
    3-16d box (31/2″ x 0.135″); or
    3-10d box (3″ × 0.128″); or
    3-3″ × 0.131″ nails; or
    3-3″ 14 gage staples,7/16″ crown|End nail| |17. Top plates, laps at corners and intersections|2-16d common (31/2″ × 0.162″); or
    3-10d box (3″ × 0.128″); or
    3-3″ × 0.131″ nails; or
    3-3″ 14 gage staples,7/16″ crown|Face nail| |18. 1″ brace to each stud and plate|3-8d box (21/2″ x 0.113″); or
    2-8d common (21/2″ × 0.131″); or
    2-10d box (3″ × 0.128″); or
    2-3″ × 0.131″ nails; or
    2-3″ 14 gage staples,7/16″ crown|Face nail| |19. 1″ × 6″ sheathing to each bearing|3-8d box (21/2″ x 0.113″); or
    2-8d common (21/2″ × 0.131″); or
    2-10d box (3″ × 0.128″); or
    2-13/4″ 16 gage staples, 1″ crown|Face nail| |20. 1″ × 8″ and wider sheathing to each bearing|3-8d common (21/2″ × 0.131″); or
    3-8d box (21/2″ x 0.113″); or
    3-10d box (3″ × 0.128″); or
    3-13/4″ 16 gage staples, 1″ crown|Face nail| |20. 1″ × 8″ and wider sheathing to each bearing|Wider than 1″ × 8″
    3-8d common (21/2″ x 0.131″); or
    4-8d box (21/2″ × 0.113″); or
    3-10d box (3″ × 0.128″); or
    4-13/4″ 16 gage staples, 1″ crown|Wider than 1″ × 8″
    3-8d common (21/2″ x 0.131″); or
    4-8d box (21/2″ × 0.113″); or
    3-10d box (3″ × 0.128″); or
    4-13/4″ 16 gage staples, 1″ crown| |Floor|Floor|Floor| |21.

  • CBC § 304.3.3 Medium relevance — show source text

    304.3.3 Criteria for incidental and minor structural alteration, additions, or repairs of pre-1973 code buildings. [OSHPD 1R, 2, 4 & 5] Provisions of this section shall apply to hospital buildings which were originally designed to pre-1973 building codes, and had no major structural alterations, additions or repairs using 1973 California Building Standards Code or later editions with an OSHPD permit. 1. Nonstructural components. Component importance factor, I p , shall be permitted to be 1.0. Exception: Components required for life safety purposes after an earthquake, including emergency, standby or alternative power systems, mechanical smoke removal systems, fire protection sprinkler systems, fire alarm control panels and egress stairways shall have a component importance factor (I p ) of 1.5.

    SECTION 305—IN-SITU LOAD TESTS

    [BS] 305.1 General. Where used, in-situ load tests shall be conducted in accordance with Section 1708 of the California Building Code .

    SECTION 306—ACCESSIBILITY FOR EXISTING BUILDINGS

    [DSA-AC] Public buildings, public accommodations, commercial facilities and public housing regulated by the Division of the State Architect-Access Compliance in Title 24, Part 2, California Building Code, Chapter 1, Section 1.9.1 shall comply with Title 24, Part 2, California Building Code, Chapter 11B.

    [HCD 1-AC] Accessibility requirements for covered multifamily dwellings, as defined in Chapter 2 of the California Building Code, are promulgated under HCD authority and are located in Chapter 11A of the California Building Code.

    SECTION 307—SMOKE ALARMS

    307.1 Smoke alarms. Where an alteration, addition, change of occupancy or relocation of a building is made to an existing building or structure of a Group R and I-1 occupancy, the existing building shall be provided with smoke alarms in accordance with the California Fire Code or Section R310 of the California Residential Code .

    Exception: Work classified as Level 1 Alterations in accordance with Chapter 7.

    SECTION 308—CARBON MONOXIDE DETECTION

    308.1 Carbon monoxide detection. Where an addition, alteration, change of occupancy or relocation of a building is made to an existing building, the existing building shall be provided with carbon monoxide detection in accordance with the California Fire Code or Section R311 of the California Residential Code .

    3-6 2025 CALIFORNIA EXISTING BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    PROVISIONS FOR ALL COMPLIANCE METHODS

    308.2 Carbon monoxide alarms in existing portions of a building. [HCD 1 & HCD 2] Pursuant to Health and Safety Code Section 17926, carbon monoxide detection shall be provided in all existing Group R buildings, as required in Section 915 of the California Building Code or Section R315 of the California Residential Code, as applicable.

  • CBC § 1.11. Medium relevance — show source text

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

    2025 CALIFORNIA EXISTING BUILDING CODE 3A-1

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    3A-2 2025 CALIFORNIA EXISTING BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    3 A PROVISIONS FOR ALL COMPLIANCE METHODS

    User notes:

    About this chapter: Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers [applications listed in Section 1.10.1 (OSHPD 1)].

    SECTION 301 A —ADMINISTRATION

    301 A .1 Applicability. The provisions of this chapter shall control the alteration, repair, addition and change of occupancy of existing structures for applications listed in Sections 1.10.1 [OSHPD 1] regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).

    California Energy Commission, State Fire Marshal and DSA-AC requirements for existing structures shall be enforced by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).

    301 A .1.1 Bleachers, grandstands and folding and telescopic seating. Existing bleachers, grandstands and folding and telescopic seating shall comply with ICC 300.

    301 A .2 Repairs. Repairs shall comply with the requirements of Chapter 4 A .

    301 A .3 Alteration, addition or change of occupancy. The alteration, addition or change of occupancy of all existing buildings or structures shall comply with one of the methods or categories listed in Section 301 A .3.1, 301 A .3.2 or 301 A .3.3. Section 304A.3.2 applies to all methods or categories. Sections 301 A .3.1 through 301 A .3.3 shall not be applied in combination with each other , except when permitted by the enforcement agency.

    Exception: Subject to the approval of the enforcement agency, alterations complying with the laws in existence at the time the building or the affected portion of the building was built shall be considered in compliance with the provisions of this code. New structural members added as part of the alteration shall comply with the California Building Code .

    301 A .3.1 Prescriptive compliance method. Alterations, additions and changes of occupancy complying with Chapter 5 A of this code for existing buildings or structures shall be considered in compliance with the provisions of this code.

  • CBC § 110.7 Medium relevance — show source text

    b. In Climate Zones 2 and 11 through 16, air seal all accessible areas of the ceiling plane between the attic and the conditioned space in accordance with Section 110.7; and Exception 1 to Section 180.2(b)1Bib: Dwelling units with at least R-19 existing insulation installed at the ceiling level.

    274 2025 CALIFORNIA ENERGY CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    MULTIFAMILY BUILDINGS—ADDITIONS, ALTERATIONS AND REPAIRS TO EXISTING MULTIFAMILY BUILDINGS

    Exception 2 to Section 180.2(b)1Bib : Dwelling units with atmospherically vented space heating or water-heating combustion appliances located inside the pressure boundary of the dwelling unit. c. In Climate Zones 1 through 4 and 8 through 16, recessed downlight luminaires in the ceiling shall be covered with insulation to the same depth as the rest of the ceiling. Luminaires not rated for insulation contact must be replaced or fitted with a fireproof cover that allows for insulation to be installed directly over the cover; and Exception to Section 180.2(b)1Bic: In Climate Zones 1 through 4 and 8 through 10, dwelling units with at least R-19 existing insulation installed at the ceiling level. d. Attic ventilation shall comply with the California Building Code requirements. Exception 1 to Section 180.2(b)1Bi: Dwelling units with at least R-38 existing insulation installed at the ceiling level. Exception 2 to Section 180.2(b)1Bi: 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 180.2(b)1Bi: Dwelling units with knob and tube wiring located in the vented attic.

    Exception 4 to Section 180.2(b)1Bi: 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 180.2(b)1Bi: Where the attic space above the altered dwelling unit is shared with other dwelling units and the requirements of Section 180.2(b)1Bi are not triggered for the other dwelling units.

    C. Fenestration alterations other than repair shall meet the requirements of Items i and ii below:

    NOTE: Glass replaced in an existing sash and frame or sashes replaced in an existing frame are considered repairs. In these cases, Section 180.2(b) requires that the replacement be at least equivalent to the original in performance. i. Fenestration installed to replace existing fenestration of the same total area shall meet either a or b: a. The maximum U- factor, RSHGC and VT requirements of Table 180.2-B, or b. The area-weighted U- factor and RSHGC of Table 170.2-A. Exception 1 to Section 180.2(b)1Ci: In an alteration, where 150 square feet or less of the entire building's vertical fenestration is replaced, RSHGC and VT requirements of Table 180.2-B shall not apply. ii.

Frequently asked questions

Who decides whether work is a “repair” under Chapter 4 or an alteration under Chapters 5–11?

The code official determines applicability; § 301.1–301.3 sets the administrative framework and § 301.2 directs repairs to Chapter 4. If scope goes beyond repair triggers, other compliance methods apply (§ 301.2; Chapter 4) file.

Can I always replace damaged components with “like” materials?

Like materials are permitted for repairs provided they do not create a hazard; however, Chapter 4 requires some replacements to meet modern performance or efficiency limits (for example, water closets) and some repairs must meet the new‑construction code when Chapter 4 requires it (§ 402.3; § 408.2) .

When will a repair trigger flood or seismic upgrade requirements?

If the repair constitutes a “substantial improvement” or repairs “substantial structural damage” in flood or seismic contexts, the code requires compliance with the applicable CBC provisions (cross‑reference to § 1612 for flood areas and to structural retrofit sections) — see § 401.3 and the § 405.2 series for triggers and required evaluations .

Do electrical, mechanical or plumbing repairs follow Chapter 4 or their respective codes?

Chapter 4 directs that repairs to those systems comply with the respective California codes (CEC, CMC, CPC); see §§ 406–408 for this cross‑reference and system‑specific limits (§ 406.1; § 407.1; § 408.1) .

Are there special repair rules for hospitals, schools or state buildings?

Yes. The CEBC contains specialized adoption and alternate sections (Chapter 4A for OSHPD facilities and references to Sections 317–322 for some state‑owned/state‑regulated buildings). Verify the applicable adoption matrix and agency‑specific chapters before applying standard Chapter 4 text (§ 401.1.2; Chapter 4A) .

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