CEBC · California Existing Building Code

Structural repairs and seismic triggers

This page orients users to CEBC rules on structural repairs, the common seismic triggers (10% and work‑area thresholds), and the main sections and compliance methods to consult.

Last reviewed: July 6, 2026

Overview

This hub covers how the California Existing Building Code treats structural repairs, when work on an existing building triggers a seismic evaluation or retrofit, and the design paths available for meeting those seismic requirements. The CEBC sets both bright‑line triggers (work-area and damage thresholds) and performance-based paths for evaluation and strengthening so repairs and alterations don’t unintentionally worsen seismic performance (§317.2–§317.4).

Key code locations to know: Chapter 4 (Repairs) — including repair rules and the substantial‑damage provisions in §405 — governs how damaged elements may be restored; Chapter 3 (Sections 317–322) establishes seismic evaluation, minimum seismic performance (Table 317.5) and retrofit obligations; and the methods for demonstrating compliance (Method A, Method B and ASCE 41 procedures) are in Sections 320–321.

Common practical triggers called out in the CEBC include cumulative changes that increase seismic demand or reduce capacity by more than 10 percent, large work areas (for some prescriptive anchorage and diaphragm requirements the 50% work‑area threshold applies), and defined cost or risk‑category changes for state buildings — all of which can require evaluation, retrofit or both.

In this section

Code references

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

  • CEBC § 317.2 High relevance — show source text

    317.2 Scope. All alterations, structurally connected additions and/or repairs to existing structures or portions thereof shall, at a minimum, be designed and constructed to resist the effects of seismic ground motions as provided in this section. The structural system shall be evaluated by a registered design professional and, if not meeting or exceeding the minimum seismic design performance requirements of this section, shall be retrofitted in compliance with these requirements.

    Exception: Those structures for which Section 317.3 determines that assessment is not required, or for which Section 317.4 determines that retrofit is not needed, then only the requirements of Section 317.11 apply.

    317.3 Applicability.

    317.3.1 Existing state-owned buildings. [BSC, DSA-SS] For existing state-owned structures including all buildings owned by the University of California and the California State University, the requirements of Section 317 apply whenever the structure is to be retrofitted, repaired or modified and any of the following apply: 1. Total construction cost, not including cost of furnishings, fixtures and equipment, or normal maintenance, for the building exceeds 25 percent of the construction cost for the replacement of the existing building. The changes are cumulative for past modifications to the building that occurred after adoption of the 1995 California Building Code and did not require seismic retrofit.

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    2. There are changes in risk category. 3. The modification to the structural components increases the seismic forces in or strength requirements of any structural component of the existing structure by more than 10 percent cumulative since the original construction, unless the component has the capacity to resist the increased forces determined in accordance with Section 319. If the building’s seismic base shear capacity has been increased since the original construction, the percent change in base shear may be calculated relative to the increased value.

    4. Structural elements need repair where the damage has reduced the lateral-load-resisting capacity of the structural system by more than 10 percent. 5. Changes in live or dead load increase story shear by more than 10 percent.

    317.3.2 Public school buildings. [DSA-SS] For public schools, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

    317.3.3 Community college buildings. [DSA-SS/CC] For community colleges, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

    317.4 Evaluation required. If the criteria in Section 317.3 apply to the project under consideration, the design professional of record shall provide an evaluation in accordance with Section 317 to determine the seismic performance of the building in its current configuration and condition. If the structure's seismic performance as required by Section 317.5 is evaluated as satisfactory and the peer reviewer(s), when Method B of Section 321 is used, concur, then no structural retrofit is required.

    _**317.5 Minimum seismic design performance levels for structural and nonstructural components.

  • CEBC § 503.7 High relevance — show source text

    [BS] 503.7 Anchorage for concrete and reinforced masonry walls. Where the work area exceeds 50 percent of the building area, the building is assigned to Seismic Design Category C, D, E or F and the building’s structural system includes concrete or reinforced masonry walls with a flexible roof diaphragm, the alteration shall comply with Section 304.3.2 by evaluation of the existing condition or by installation of wall anchors at the roof line.

    [BS] 503.8 Anchorage for unreinforced masonry walls in major alterations. Where the work area exceeds 50 percent of the building area, the building is assigned to Seismic Design Category C, D, E or F and the building’s structural system includes unreinforced masonry bearing walls, the alteration shall comply with Section 304.3.2 by evaluation of the existing condition or by installation of wall anchors at the floor and roof lines.

    [BS] 503.9 Bracing for unreinforced masonry parapets in major alterations. Where the work area exceeds 50 percent of the building area, and where the building is assigned to Seismic Design Category C, D, E or F, and the building has parapets constructed of unreinforced masonry, the alteration shall comply with Section 304.3.2 by evaluation of the existing condition or by installation of parapet bracing to resist out-of-plane seismic forces.

    [BS] 503.10 Anchorage of unreinforced masonry partitions in major alterations. Where the work area exceeds 50 percent of the building area, or where the building is assigned to Seismic Design Category C, D, E or F, and the building has unreinforced masonry partitions and nonstructural walls, the alteration work shall include evaluation of the existing condition or removal, anchoring or alteration of any such partitions or walls within the work area and adjacent to egress paths from the work area, to comply with Section 304.3.2.

    [BS] 503.11 Substantial structural alteration. Where the work area exceeds 50 percent of the building area and where work involves a substantial structural alteration, the lateral load-resisting system of the altered building shall satisfy the requirements of Section 1609 of the California Building Code and Section 304.3.2 of this code. Where the building is assigned to Seismic Design Category D or F, supports and attachments for nonstructural components required to serve any portion of the building with a use included in Risk Category IV shall comply with Section 1613 of the California Building Code or shall comply with ASCE 41 using an objective of Position Retention nonstructural performance with the BSE-1E earthquake hazard level.

    Exceptions:

    1. Buildings of Group R occupancy with not more than five dwelling or sleeping units used solely for residential purposes that are altered based on the conventional light-frame construction methods of the California Building Code or in compliance with the provisions of the California Residential Code .
    2. Where the intended alteration involves structural components of the lowest story of a building, only the lateral loadresisting system above that story need not comply with this section.

    [BS] 503.12 Roof diaphragms resisting wind loads in high-wind regions. Where the intended alteration requires a permit for reroofing and involves removal of roofing materials from more than 50 percent of the roof diaphragm of a building or section of a building located where the basic wind speed, V, is greater than 130 mph (58 m/s) in accordance with Figure 1609.3(2) of the California

  • CEBC § 1.5. High relevance — show source text

    Exception: Components required for life-safety purposes after an earthquake, including emergency and standby 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.

    304A.3.1.2 Major structural alteration, additions or repairs. Major structural alterations, additions or repairs shall be in accor- dance with Section 304A.3.4.1 or 304A.3.4.3 as applicable.

    304A.3.2 Seismic evaluation and retrofit of general acute care hospitals for compliance with the California Administrative Code, Chapter 6. Notwithstanding any other requirements of this code, existing general acute care hospitals shall comply with the seismic evaluation requirements specified in Chapter 6, of the California Administrative Code, when applicable. Seismic retrofit to comply with requirements specified in Chapter 6 of the California Administrative Code shall be permitted to be in accordance with these provisions. When load combinations which do not include seismic forces are required, the new building provisions of this code shall be applicable.

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    304A.3.3 SPC-4D. Nonconforming hospital buildings satisfying the following requirements and one of Sections 501A.3.1, 501A.3.2 or 304A.3.4.5, but not a combination thereof, shall be considered to satisfy the requirements of SPC-4D. 1. Approval of construction documents based on building characterization in accordance with the California Administrative Code (CAC) Chapter 6 Section 2.1.2.1, material properties in accordance with the CAC Chapter 6 Section 2.1.2.2 and Section 304A.5.3 of this code, and a complete rational structural analysis shall be required. 2. Where the SPC-4D upgrade involves construction, a building permit prior to construction shall be required. 3. Where multiple building permits are used to upgrade a building to SPC-4D, a complete rational structural analysis to justify compliance with SPC-4D, for the building in its final configuration, shall be submitted as part of the construction documents submittal to the Office for the last project. 4. Where the SPC-4D upgrade involves construction, buildings shall be assigned to SPC-4D after all projects required for SPC- 4D are closed in compliance.

    304A.3.4 Performance objectives of performance-based methods. Except for the modifications as set forth in Sections 304A.3.4, 304A.3.5 (for ASCE 41-13), and 304A.3.6 (for ASCE 41-23) of this code, all additions, alterations, repairs and seismic retrofit to existing structures or portions thereof shall be permitted to be designed in accordance with the provisions of ASCE 41-23.

    Use of ASCE 41-13 shall be limited to SPC-2 and SPC-4D buildings only.

  • CEBC § 2.3.9 High relevance — show source text

    Σ W d = Total dead load of all the diaphragms at and above the level under consideration, pounds (N).

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    APPENDIX A—GUIDELINES FOR THE SEISMIC RETROFIT OF EXISTING BUILDINGS

    SECTION A105—GENERAL REQUIREMENTS

    [BS] A105.1 General. The seismic force-resisting system specified in this chapter shall comply with the California Building Code and referenced standards, except as modified herein.

    [BS] A105.2 Alterations and repairs. Alterations and repairs required to meet the provisions of this chapter shall comply with applicable structural requirements of the building code unless specifically provided for in this chapter.

    [BS] A105.3 Requirements for plans. The following construction information shall be included in the plans required by this chapter:

    1. Dimensioned floor and roof plans showing existing walls and the size and spacing of floor and roof-framing members and sheathing materials. The plans shall indicate all existing URM walls, and new crosswalls and shear walls, and their materials of construction. The location of these walls and their openings shall be fully dimensioned and drawn to scale on the plans.
    2. Dimensioned URM wall elevations showing openings, piers, wall classes as defined in Section A106.2.3.9, thickness, heights, wall shear test locations, cracks or damaged portions requiring repairs, the general condition of the mortar joints, and if and where pointing is required. Where the exterior face is veneer, the type of veneer, its thickness and its bonding and/or ties to the structural wall masonry shall be noted.
    3. The type of interior wall and ceiling materials, and framing.
    4. The extent and type of existing wall anchorage to floors and roof where used in the design.
    5. The extent and type of parapet corrections that were previously performed, if any.
    6. Repair details, if any, of cracked or damaged unreinforced masonry walls required to resist forces specified in this chapter.
    7. All other plans, sections and details necessary to delineate required retrofit construction.
    8. The design procedure used shall be stated on both the plans and the permit application.
    9. Details of the anchor prequalification program required by Section A107.5.3, if used, including location and results of all tests.
    10. Quality assurance requirements of special inspection for all new construction materials and for retrofit construction including: anchor tests, pointing or repointing of mortar joints, installation of adhesive or mechanical anchors, and other elements as deemed necessary to ensure compliance with this chapter.

    [BS] A105.4 Structural observation, testing and inspection. Structural observation, in accordance with Section 1704.6 of the Cali- fornia Building Code, shall be required for all structures in which seismic retrofit is being performed in accordance with this chapter. Structural observation shall include visual observation of work for compliance with the approved construction documents and confirmation of existing conditions assumed during design. Structural testing and inspection for new and existing construction materials shall be in accordance with the building code, except as modified by this chapter. Special inspection as described in Section A105.3, Item 10, shall be provided equivalent to Level 3 as prescribed in TMS 402, Table 3.1(2).

    SECTION A106—MATERIALS REQUIREMENTS

  • CEBC § 319.8. High relevance — show source text

    unless it can be demonstrated that_ reduced capacity meets the requirements of Section 319.8. 2. The lateral loading to or strength requirement of existing structural components is not increased beyond their capacity. 3. New structural components are detailed and connected to the existing structural components as required by the California Building Code. 4. New or relocated nonstructural components are detailed and connected to existing or new structural components as required by the California Building Code. 5. A dangerous condition is not created.

    Use of ASCE 41 Tier 1 and Tier 2 deficiency only retrofit procedures are pre-approved for use where Section 317.3 does not require an

    assessment.

    319.12.1 State-owned buildings. [BSC] Voluntary modifications to lateral force-resisting systems conducted in accordance with Appendix A of this code and the referenced standards of the California Building Code shall be permitted.

    319.12.1.1 Design documents. [BSC] When Section 319.12 is the basis for structural modifications, the approved design documents must clearly state the scope of the seismic modifications and the accepted criteria for the design. The approved design documents must clearly have the phrase “The seismic requirements of the California Existing Building Code have not been checked to determine if these structural modifications meet the full seismic evaluation and strengthening requirements of Sections 317-322: the modifications proposed are to a different seismic performance standard than would be required in Section 319 if they were not voluntary as allowed in Section 319.12.”

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    319.12.2 Public schools and community colleges. [DSA-SS, DSA-SS/CC] When Section 319.12 is the basis for structural modifications, the approved design documents must clearly indicate the scope of modifications and the acceptance criteria for the design.

    SECTION 320 [BSC, DSA-SS & DSA-SS/CC]—METHOD A

    320.1 General. The retrofit design shall employ the Linear Static or Linear Dynamic Procedures of ASCE 41, Section 7.4.1 or 7.4.2, and comply with the applicable general requirements of ASCE 41, Chapters 6 and 7. The earthquake hazard level and performance level given specified in Section 317.5 for the building’s risk category shall be used. Structures shall be designed for seismic forces coming from any horizontal direction.

    SECTION 321 [BSC, DSA-SS & DSA-SS/CC]—METHOD B

    321.1 The existing or retrofitted structure shall be demonstrated to have the capability to sustain the deformation response due to the specified earthquake ground motions and meet the seismic performance requirements of Section 317. The registered design professional shall provide an evaluation of the response of the existing structure in its modified configuration and condition to the ground motions specified. If the building’s seismic performance is evaluated as satisfactory and the peer reviewer(s) and the enforcement agency concurs, then no further structural retrofit and/or repair of the lateral load-resisting system is required.

  • CEBC § 317.3.2 High relevance — show source text

    2. There are changes in risk category. 3. The modification to the structural components increases the seismic forces in or strength requirements of any structural component of the existing structure by more than 10 percent cumulative since the original construction, unless the component has the capacity to resist the increased forces determined in accordance with Section 319. If the building’s seismic base shear capacity has been increased since the original construction, the percent change in base shear may be calculated relative to the increased value.

    4. Structural elements need repair where the damage has reduced the lateral-load-resisting capacity of the structural system by more than 10 percent. 5. Changes in live or dead load increase story shear by more than 10 percent.

    317.3.2 Public school buildings. [DSA-SS] For public schools, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

    317.3.3 Community college buildings. [DSA-SS/CC] For community colleges, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

    317.4 Evaluation required. If the criteria in Section 317.3 apply to the project under consideration, the design professional of record shall provide an evaluation in accordance with Section 317 to determine the seismic performance of the building in its current configuration and condition. If the structure's seismic performance as required by Section 317.5 is evaluated as satisfactory and the peer reviewer(s), when Method B of Section 321 is used, concur, then no structural retrofit is required.

    317.5 Minimum seismic design performance levels for structural and nonstructural components. Following the notations of ASCE 41, the seismic requirements for design and assessment are based upon a prescribed Seismic Hazard Level (BSE-1N, BSE-2N, BSE-1E, BSE-R or BSE-C), a specified structural performance level (S-1 through S-5) and a nonstructural performance level (N-A through N-E). The minimum seismic performance criteria are given in Table 317.5 according to the Building Regulatory Authority and the Risk Category as determined in Chapter 16 of the California Building Code or by the regulatory authority. The building shall be evaluated in accordance with a Tier 3 Systematic Evaluation and Retrofit per ASCE 41 Chapter 6 for both the Level 1 and Level 2 performance levels, and the more restrictive requirements shall apply.

    Exception: If the floor area of an addition is greater than the larger of 50 percent of the floor area of the original building or 1,000 square feet (93 m [2] ), then the Table 317.5 entries for BSE-R (or BSE-1E) and BSE-C are replaced by BSE-1N and BSE-2N, respectively.

    |TABLE 317.5—SEISMIC PERFORMANCE REQUIREMENTS2,

  • CEBC § 304A.3.4.5 High relevance — show source text

    Use_ of Section 304A.3.4.5 to rehabilitate SPC-3, SPC-4D and SPC-4 buildings will result in re-classification of the building to SPC-4D. Noncompliant SPC-4 buildings may be rehabilitated to SPC-5 in accordance with Section 304A.3.4.6 using the reduced seismic hazard. New structural members and connections required by this rehabilitation design shall comply with the detailing provisions of this code for new buildings of similar structure, purpose and location.

    405 A .2.4 Substantial structural damage to gravity load-carrying components. Gravity load-carrying components that have sustained substantial structural damage shall be retrofitted to comply with the applicable provisions for dead, live and snow loads in the California Building Code . Undamaged gravity load-carrying components, including undamaged foundation components, that receive dead, live or snow loads from retrofitted components shall also be retrofitted if required to comply with these design loads. New structural members and connections required by this rehabilitation design shall comply with the detailing provi- sions of this code for new buildings of similar structure, purpose and location.

    405 A .2.4.1 Lateral force-resisting elements. Regardless of the level of damage to vertical elements of the lateral force-resisting system, if substantial structural damage to gravity load-carrying components was caused primarily by wind or seismic effects, then the building shall be evaluated in accordance with Section 405 A .2.3.1 and, if noncompliant, retrofitted in accordance with Section 405 A .2.3.3.

    Exceptions:

    1. Buildings assigned to Seismic Design Category A, B or C whose substantial structural damage was not caused by earthquake need not be evaluated or retrofitted for load combinations that include earthquake effects.
    2. One- and two-family dwellings need not be evaluated or retrofitted for load combinations that include earthquake effects.

    405 A .2.5 Substantial structural damage to snow load-carrying components. Where substantial structural damage to any snow load-carrying components is caused by or related to snow load effects, any components required to carry snow loads on roof framing of similar construction shall be repaired, replaced or retrofitted to satisfy the requirements of Section 1608 of the California Building Code .

    405 A .2.6 Flood hazard areas. In flood hazard areas, buildings that have sustained substantial damage shall be brought into compliance with Section 1612 A of the California Building Code .

    SECTION 406 A —ELECTRICAL

    406 A .1 General. Existing electrical wiring and equipment undergoing repair shall be in accordance with Title 24 Part 3 California Electri- cal Code (CEC).

    406 A .1.1 Reconditioned electrical equipment. Reconditioned electrical equipment shall comply with the California Electrical Code . Electrical equipment prohibited from being reconditioned by the applicable sections of the California Electrical Code shall not be reconditioned unless permitted by NFPA 99.

    406 A .1.2 Health care facilities. Portions of electrical systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.

    SECTION 407 A —MECHANICAL

  • CEBC § 1402.2 High relevance — show source text

    [BS] 1402.2 Foundation. The foundation system of relocated buildings shall comply with the California Building Code or the Califor- nia Residential Code, as applicable.

    [BS] 1402.2.1 Connection to the foundation. The connection of the relocated building to the foundation shall comply with the California Building Code or the California Residential Code, as applicable.

    [BS] 1402.3 Wind loads. Buildings shall comply with California Building Code or California Residential Code wind provisions, as applicable.

    Exceptions:

    1. Detached one- and two-family dwellings and Group U occupancies where wind loads at the new location are not higher than those at the previous location.
    2. Structural elements whose stress is not increased by more than 10 percent.

    [BS] 1402.4 Seismic loads. Buildings shall comply with California Building Code or California Residential Code seismic provisions at the new location, as applicable.

    Exceptions:

    1. Structures in Seismic Design Categories A and B and detached one- and two-family dwellings in Seismic Design Categories A, B and C where the seismic loads at the new location are not higher than those at the previous location.
    2. Structural elements whose stress is not increased by more than 10 percent.

    [BS] 1402.5 Snow loads. Structures shall comply with California Building Code or California Residential Code snow loads, as applicable, where snow loads at the new location are higher than those at the previous location.

    Exception: Structural elements whose stress is not increased by more than 5 percent.

    [BS] 1402.6 Flood hazard areas. If relocated or moved into a flood hazard area, structures shall comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable.

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    RELOCATED OR MOVED BUILDINGS

    [BS] 1402.7 Required inspection and repairs. The code official shall be authorized to inspect, or to require approved professionals to inspect at the expense of the owner, the various structural parts of a relocated building to verify that structural components and connections have not sustained structural damage. Any repairs required by the code official as a result of such inspection shall be made prior to the final approval.

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    CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 15 – CONSTRUCTION SAFEGUARDS

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

    Adopting Agency BSC BSC-
    CG
    SFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC
    Adopting
  • CEBC § 319.1 High relevance — show source text

    Buildings complying with the requirements of the exception in Section 319.1 are deemed to meet the seismic performance requirements of this section._
    4. State-owned and state-leased essential services buildings are subject to the regulatory authority of DSA-SS per Section 1.9.2.1.|

    317.6 Retrofit required. Where the evaluation indicates the building does not meet the required performance objectives of this section, the owner shall take appropriate steps to ensure that the building’s structural system is retrofitted in accordance with the provisions of Section 317. Appropriate steps are either: 1) undertake the seismic retrofit as part of the additions, alterations and/or repairs of the structure; or 2) provide a plan, acceptable to the building official, to complete the seismic retrofit in a timely manner. The relocation or moving of an existing building is considered to be an alteration requiring filing of the plans and specifications approved by the building official.

    317.7 The additions, alteration or repair to any existing building are permitted to be prepared in accordance with the structural and nonstructural requirements for a new building as given in the California Building Code, applied to the entire building.

    317.8 The requirements of ASCE 41 Chapters 14 and 15 are to apply to the use of seismic isolation and passive energy systems, respectively, for the repair, voluntary lateral-force-resisting system modification or retrofit of an existing structure. When seismic isolation or passive energy dissipation is used, the project must have project peer review as prescribed in Section 322.

    317.9 Any construction required by this chapter shall include structural observation by the registered design professional who is responsible for the structural design in accordance with Section 319.10.

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    317.10 Where Method B of Section 321 is used or is required by Section 319.7, the proposed method of building evaluation and design procedures must be accepted by the building official prior to the commencement of the work.

    317.11 Voluntary lateral-force-resisting system modifications. Where the exception of Section 317.2 applies, modifications of existing structural components and additions of new structural components that are initiated for the purpose of improving the seismic performance of an existing structure and that are not required by other portions of this chapter are permitted under the requirements of Section 319.12.

    SECTION 318 [BSC, DSA-SS & DSA-SS/CC]—DEFINITIONS

    318.1 In addition to the definitions given in Section 202, for the purposes of Sections 317 through 323, certain terms are defined as follows:

    [DSA-SS & DSA-SS/CC] For the purposes of Section 317 through 323, definitions of terms given in Section 4-207 or 4-314 of the California Administrative Code govern over those in Section 202.

    ADDITION [BSC] means any work that increases the floor or roof area or the volume of enclosed space of an existing building, and is structurally attached to the existing building by connections that are required for transmitting vertical or horizontal loads between the addition and the existing structure.

  • CEBC § 2.1 High relevance — show source text

    SECTION 302 A —GENERAL PROVISIONS

    302 A .1 Dangerous conditions. The code official shall have the authority to require the elimination of conditions deemed dangerous.

    302 A .2 Additional codes. Alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and struc- tures shall comply with the provisions for alterations, repairs, additions and changes of occupancy or relocation, respectively, in the California Fire Code, California Mechanical Code, California Plumbing Code and California Electrical Code. Where provisions of the other codes conflict with provisions of this chapter, the provisions of this chapter shall take precedence.

    302 A .2.1 Additional codes in health care. In existing Group I-2 occupancies, ambulatory health care facilities, outpatient clinics and hyperbaric facilities, alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and structures shall also comply with NFPA 99.

    302 A .3 Existing materials and equipment. Materials and equipment already in use in a building in compliance with requirements or approvals in effect at the time of their erection or installation shall be permitted to remain in use unless determined by the code official to be unsafe in accordance with California Building Code Section 116.

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    302A.3.1 Existing seismic force-resisting systems. Where the existing seismic force-resisting system is a type that can be designated ordinary or is a welded steel moment frame constructed under a permit issued prior to October 25, 1994, values of R, W0 and Cd for the existing seismic force-resisting system shall be those specified by the California Building Code for an ordinary system unless it is demonstrated that the existing system will provide performance equivalent to that of a detailed, intermediate or special system.

    302 A .4 New and replacement materials. Except as otherwise required or permitted by this code, materials and equipment permitted by the applicable code for new construction shall be used. Like materials shall be permitted for repairs and alterations, provided no hazard to life, health or property is c reated. Hazardous materials shall not be used where the code for new construction would not permit their use in buildings of similar occupancy, purpose and location.

    302 A .4.1 New structural members and connections. New structural members and connections shall comply with the detailing provisions of the California Building Code for new buildings of similar structure, purpose and location.

    Exception: Where alternative design criteria are specifically permitted.

    302 A .5 Occupancy and use. Where determining the appropriate application of the referenced sections of this code, the occupancy and use of a building shall be determined in accordance with Chapter 3 of the California Building Code .

  • CEBC § 7.12 High relevance — show source text

    SECTION 303 A RESERVED

    SECTION 304 A —STRUCTURAL DESIGN LOADS AND EVALUATION AND DESIGN PROCEDURES

    304 A .1 Live loads. Where an addition or alteration does not result in increased design live load, existing gravity load-carrying structural elements shall be permitted to be evaluated and designed for live loads approved prior to the addition or alteration. If the approved live load is less than that required by Section 1607 A of the California Building Code, the area designated for the nonconforming live load shall be posted with placards of approved design indicating the approved live load. Where the addition or alteration results in increased design live load, the live load required by Section 1607 A of the California Building Code shall be used.

    304 A .2 Snow loads on adjacent buildings. Where an alteration or addition changes the potential snow drift effects on an adjacent building, the code official is authorized to enforce Section 7.12 of ASCE 7.

    304 A .3 Additions, alterations, repairs and seismic retrofit to existing buildings or structures.

    304 A .3.1 Structures designed in accordance with pre-1973 building code. Provisions of this section shall apply to hospital build- ings which were originally designed to pre-1973 building codes and not designated as SPC 3 or higher in accordance with Chapter 6 of the California Administrative Code.

    304A.3.1.1 Incidental and minor structural alteration, additions, or repairs. Incidental and minor structural additions shall be permitted, provided the additions meet the California Building Code for new construction using importance factor, I e , equal to or greater than 1.0. Alterations or repair to existing gravity and lateral force-resisting systems shall be made to conform to the requirements of Section 503A or Chapter 4A, respectively, using importance factor, I e , equal to or greater than 1.0. 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 and standby 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.

    304A.3.1.2 Major structural alteration, additions or repairs. Major structural alterations, additions or repairs shall be in accor- dance with Section 304A.3.4.1 or 304A.3.4.3 as applicable.

    304A.3.2 Seismic evaluation and retrofit of general acute care hospitals for compliance with the California Administrative Code, Chapter 6. Notwithstanding any other requirements of this code, existing general acute care hospitals shall comply with the seismic evaluation requirements specified in Chapter 6, of the California Administrative Code, when applicable. Seismic retrofit to comply with requirements specified in Chapter 6 of the California Administrative Code shall be permitted to be in accordance with these provisions. When load combinations which do not include seismic forces are required, the new building provisions of this code shall be applicable.

  • CEBC § 401.3 Medium relevance — show source text

    [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.

    [BS] 405.2 Repairs to damaged buildings. Repairs to damaged buildings shall comply with this section.

    [BS] 405.2.1 Repairs for less than substantial structural damage. Unless otherwise required by this section, for damage less than substantial structural damage, the damaged elements shall be permitted to be restored to their predamage condition.

    [BS] 405.2.1.1 Snow damage. Structural components whose damage was caused by or related to snow load effects shall be repaired, replaced or altered to satisfy the requirements of Section 1608 of the California Building Code .

    [BS] 405.2.2 Disproportionate earthquake damage. A building assigned to Seismic Design Category D, E or F that has sustained disproportionate earthquake damage shall be subject to the requirements for buildings with substantial structural damage to vertical elements of the lateral force-resisting system.

    [BS] 405.2.3 Substantial structural damage to vertical elements of the lateral force-resisting system. A building that has sustained substantial structural damage to the vertical elements of its lateral force-resisting system shall be evaluated in accordance with Section 405.2.3.1, and either repaired in accordance with Section 405.2.3.2 or repaired and retrofitted in accordance with Section 405.2.3.3, depending on the results of the evaluation.

    Exceptions:

    1. Buildings assigned to Seismic Design Category A, B or C whose substantial structural damage was not caused by earthquake need not be evaluated or retrofitted for load combinations that include earthquake effects.

    2025 CALIFORNIA EXISTING BUILDING CODE 4-3

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

    REPAIRS

Frequently asked questions

When does a repair or alteration require a seismic evaluation?

If the project meets the CEBC criteria in §317.3 — for example cumulative work that increases seismic forces or strength requirements by more than 10%, damage that reduces lateral‑load capacity by more than 10%, changes in risk category, or certain cost thresholds for state buildings — a seismic evaluation per Section 317 is required.

If an evaluation shows the building meets performance objectives, must I still retrofit?

No. If the required evaluation (including peer review when Method B is used) demonstrates the building meets the minimum seismic performance in §317.5, no additional structural retrofit is mandated; if it does not, §317.6 requires the owner to undertake retrofit or present an approved plan to do so.

What compliance procedures apply for seismic repairs and retrofits?

The CEBC permits prescriptive (work‑area) approaches and performance‑based procedures using ASCE 41 (including Tiered/Systematic evaluations) via the Methods described in Sections 320–321; projects using isolation or passive energy systems, or certain voluntary modifications, may also trigger peer review and additional provisions.

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