CEBC · California Existing Building Code
How do I choose Method A or Method B for seismic evaluation and design?
If your building is not prestressed, not irregular, not Risk Category IV, under 240 ft tall and does not need nonlinear analysis, you may use Method A (the prescriptive ASCE 41 linear procedures). If it has any of the listed disqualifying features or you prefer a performance demonstration, you must use Method B — which requires an independent peer review and acceptance by the building official.
Last reviewed: July 6, 2026
What the code requires — plain English
One of three approaches must be used for seismic evaluation and retrofit of existing buildings: Method A, Method B, or the state‑specific procedures listed in § 319.1. Method A is the prescriptive Linear Static/Linear Dynamic approach (ASCE 41 procedures) and Method B is a performance/analysis‑driven approach that requires independent peer review and building‑official approval. Use of Method B also requires prior acceptance of the evaluation/design approach by the building official and peer reviewer where required. § 319.1 ; § 320 ; § 321 .
The single most important rule: if your building has any of the specific disqualifying characteristics in § 319.7, you must use Method B; otherwise Method A is permitted unless you choose Method B. § 319.7 .
Requirements in detail
Big picture: where each method sits
- Method A — prescriptive retrofit using the Linear Static or Linear Dynamic procedures of ASCE 41 (used where the prescriptive path is allowed). § 320.1 .
- Method B — analysis/performance demonstration of deformation and response to the specified ground motions; requires peer review and building‑official acceptance of the approach. § 321.1, § 321.2 .
- The authority explicitly allows Method B for any building (it is not limited) — Method B may be used for any existing building. § 319.6 .
Decision‑relevant factors (quick table)
| Decision factor | Key threshold / condition | Likely required method | Code Reference |
|---|---|---|---|
| Prestressed, post‑tensioned or precast structural components present | Any such components (beams, columns, walls, slabs) | Method B required | § 319.7.1 |
| Building configuration is irregular | Classified irregular under § 319.5 / ASCE 41 definitions | Method B required (exceptions apply if retrofit removes the irregularity or demonstration shows irregularity not affecting performance) | § 319.7.2 |
| Risk Category IV | Assigned to Risk Category IV | Method B required | § 319.7.3 |
| Undefined or hybrid structural system | System not classifiable into a standard system | Method B required | § 319.7.4 |
| Seismic isolation or energy‑dissipation system exists or is proposed | Existing or retrofit includes isolation/dissipation | Method B required | § 319.7.5 |
| Building height | Greater than 240 ft (73 m) | Method B required | § 319.7.6 |
| Project requires nonlinear analysis / ASCE 41 application requires nonlinear | Use of nonlinear procedures | Method B required | § 319.7.7 |
| Owner or design team elects performance demonstration | Any building where team prefers performance verification | Method B permitted (subject to peer review and building official approval) | § 319.6, § 321.2 |
Process differences you must know
- Method A design work shall employ the Linear Static or Linear Dynamic procedures of ASCE 41, Sections 7.4.1/7.4.2 and meet ASCE 41 general requirements (Chapters 6 & 7). § 320.1 .
- Method B requires the design/evaluation approach, models and assumptions be peer‑reviewed and accepted by the reviewer and the enforcement agency; any analysis method is permitted if accepted. Nonlinear ground motion representation must be approved prior to analysis. § 321.2 — § 321.2.4 .
- Peer review selection and timing: when Method B is used, the peer reviewer must be selected early, be independent, be a CA-licensed structural engineer (or otherwise approved), and review the proposed procedures per § 322. § 319.1 also states Method B requires independent review as required in § 322. § 322.1–322.3 and § 319.1 .
Exceptions & special cases
- State‑owned buildings may use specific Appendix A procedures (e.g., URM provisions) instead of Methods A/B for certain building types without peer review — see § 319.1.1. § 319.1.1 .
- If a building is irregular but the retrofit removes that irregularity, or if the irregularity is shown not to affect seismic performance, Method A may still be used (exception to § 319.7.2). § 319.7.2 (Exceptions) .
- The enforcement agency may perform, modify, or waive peer review where qualified staff is available or where appropriate (exceptions in § 321.2 / § 322). § 321.2 (Exceptions) .
- Method B is permitted for any building; even when Method A is allowed by prescriptive selection, the owner/design team may still choose Method B provided the building official and peer reviewer accept the approach. § 319.6, § 321.2.1 .
Common mistakes
- Assuming Method A is always allowed when not listed in § 319.7 — remember Method B is allowed for any building and may be required where characteristics in § 319.7 exist. § 319.6, § 319.7 .
- Failing to obtain building‑official acceptance before starting Method B work. When Method B is used (or required), the proposed evaluation/design procedures must be accepted by the building official prior to substantial work. § 317.10 .
- Skipping peer review steps: Method B requires independent peer review per § 322; selecting a non‑independent reviewer or doing peer review too late can invalidate acceptance. § 319.1, § 322.1–322.3 .
- Misclassifying “irregular” vs. “regular”: use the classification criteria in § 319.5 (ASCE 7 / ASCE 41 definitions depending on which standard is applied) — incorrect classification changes whether Method B is mandatory. § 319.5, § 319.7.2 .
- Designing with Method A procedures under Method B without peer‑review approval: while Method A procedures may be used under Method B, the overall approach must be acceptable to the peer reviewer and enforcement agency. § 321.2.1 .
Worked example — a concrete scenario with numbers
Scenario: Owner is altering a 3‑story, regular reinforced concrete office building, existing height = 35 ft, Risk Category = II, no prestressed/precast members, no seismic isolation, and no plan to use nonlinear analysis.
Step 1 — Check disqualifiers (§ 319.7):
- Prestressed/precast? No → not § 319.7.1.
- Irregular? No → not § 319.7.2.
- Risk Category IV? No (it's Category II) → not § 319.7.3.
- Undefined/hybrid system? No.
- Isolation/energy dissipation? No.
- Height > 240 ft? No.
- Nonlinear analysis required? No.
Conclusion: None of the § 319.7 disqualifiers apply, so the prescriptive path is permitted. § 319.7 .
Step 2 — Choose method:
- Because prescriptive path is permitted and simplest, choose Method A (Linear Static or Linear Dynamic ASCE 41 procedures). § 320.1 .
Step 3 — Design steps (high level):
- Collect data per ASCE 41 / CEBC data requirements (existing plans, field observations). (Refer to data collection requirements in Chapter 6 / § 319.x references.)
- Apply ASCE 41 Linear Static procedure (Section 7.4.1) or Linear Dynamic (7.4.2) using the seismic hazard and performance level required in Table 317.5 for Risk Category II. Design for seismic forces from any horizontal direction. § 320.1 and § 317.5 .
Step 4 — Peer review:
- Peer review is not mandated for Method A itself, but would be required if the project team instead chose Method B. If you remain on Method A, proceed with typical plan submittal to the building official. § 321.2 and § 319.6 .
If at any point you discover prestressed members, an irregular configuration, or choose nonlinear analysis, stop and switch to Method B, obtain peer reviewer selection/approval, and have the method and seismic criteria accepted by the building official before proceeding. § 319.7, § 319.1, § 321.2, § 322 .
Related provisions
- § 317 — Scope, applicability, required evaluations and performance levels (overall retrofit framework).
- § 317.10 — Requirement to have Method B procedures accepted by building official prior to work.
- § 319.1.1 — State‑owned building specific procedures (Appendix A options).
- § 319.5 — Definitions and classification of irregular vs. regular configurations.
- § 322 — Peer review requirements (qualifications, timing, independence).
Code references
Grounded in the retrieved California Existing Building Code — click a citation to read the verbatim passage:
CEBC § 3.3. High relevance — show source text
BSE-C RESPONSE ACCELERATION PARAMETERS [BSC] are the parameters (S XS and S X1 ) taken from 5-percent/50-year maximum direction spectral response acceleration curves or by a Site Specific Response Spectrum developed in accordance with ASCE 41, Section 2.3.3.
BSE-R RESPONSE ACCELERATION PARAMETERS [BSC] are the parameters (S XS and S X1 ) taken from 20-percent /50-year maximum direction spectral response acceleration curves or by a Site Specific Response Spectrum developed in accordance with ASCE 41, Section 2.3.3.
SECTION 319 [BSC, DSA-SS & DSA-SS/CC]—SEISMIC CRITERIA SELECTION FOR EXISTING BUILDINGS
319.1 Basis for evaluation and design. This section determines what technical approach is to be used for the seismic evaluation and design for existing buildings. For those buildings or portions of buildings for which Section 317 requires action, the procedures and limitations for the evaluation of existing buildings and design of retrofit systems and/or repair thereof shall be implemented in accordance with this section.
One of the following approaches must be used: 1. Method A of Section 320;
2. Method B of Section 321, with independent review of a peer reviewer as required in Section 322; or 3. For state-owned buildings only, the use of one of the specific procedures listed in Section 319.1.1.
When Method B is chosen it must be approved by the building official, and, where applicable, by the peer reviewer. All referenced standards in ASCE 41 shall be replaced by referenced standards listed in Chapter 35 of the California Building Code.
Exceptions: 1. [BSC] For buildings constructed to the requirements of California Building Code, 2019 or later edition, as adopted by the governing jurisdiction, that code is permitted to be used in place of those specified in Section 319.1. 2. [DSA-SS & DSA-SS/CC] For the conversion of nonconforming buildings to conforming school buildings in accordance with Section 4-307 of the California Administrative Code, nonconforming buildings constructed to the requirements of California Building Code, 2019 or later edition, that code as it was adopted by the governing jurisdiction is permitted to be used in place of those specified in Section 319.1 provided the building complies with Seismic Design Category D or higher.
319.1.1 Specific procedures. [BSC] For state-owned buildings, the following specific procedures located in Appendix A may be used, without peer review, for their respective types of construction to comply with the seismic performance requirements for Risk Category I, II or III buildings: 1. Seismic Strengthening Provisions for Unreinforced Masonry Bearing Wall Buildings (Chapter A1). 2. Earthquake Hazard Reduction in Existing Reinforced Concrete and Reinforced Masonry Wall Buildings with Flexible Diaphragms (Chapter A2).
319.1.2 When a design project is begun under Method B the selection of the peer reviewer is subject to the approval of the building official. Following approval by the peer reviewer, the seismic criteria for the project and the planned evaluation provisions must be approved by the building official. The approved seismic criteria and evaluation provisions shall apply. Upon approval of the building official these are permitted to be modified.
CEBC § 3-17 High relevance — show source text
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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.
ALTERATION [BSC] means any change within or to an existing building, which does not increase and may decrease the floor or roof area or the volume of enclosed space.
BSE-C RESPONSE ACCELERATION PARAMETERS [BSC] are the parameters (S XS and S X1 ) taken from 5-percent/50-year maximum direction spectral response acceleration curves or by a Site Specific Response Spectrum developed in accordance with ASCE 41, Section 2.3.3.
BSE-R RESPONSE ACCELERATION PARAMETERS [BSC] are the parameters (S XS and S X1 ) taken from 20-percent /50-year maximum direction spectral response acceleration curves or by a Site Specific Response Spectrum developed in accordance with ASCE 41, Section 2.3.3.
SECTION 319 [BSC, DSA-SS & DSA-SS/CC]—SEISMIC CRITERIA SELECTION FOR EXISTING BUILDINGS
319.1 Basis for evaluation and design. This section determines what technical approach is to be used for the seismic evaluation and design for existing buildings. For those buildings or portions of buildings for which Section 317 requires action, the procedures and limitations for the evaluation of existing buildings and design of retrofit systems and/or repair thereof shall be implemented in accordance with this section.
One of the following approaches must be used: 1. Method A of Section 320;
2. Method B of Section 321, with independent review of a peer reviewer as required in Section 322; or 3. For state-owned buildings only, the use of one of the specific procedures listed in Section 319.1.1.
CEBC § 319.3 High relevance — show source text
Where original building plans and specifications are not available, “as-built” plans shall be prepared that depict the existing vertical and lateral structural systems, exterior elements, foundations and nonstructural systems in sufficient detail to complete the design.
Data collection shall be directed and observed by the project structural engineer or design professional in charge of the design.
319.3 Site geology and soil characteristics. Soil profile shall be assigned in accordance with the requirements of Chapter 18 of the California Building Code.
319.4 Risk categories. Each structure shall be placed in one of the Risk Categories in accordance with the requirements of the California Building Code.
319.5 Configuration requirements. Each structure shall be designated structurally regular or irregular. If the evaluation and retrofit is in accordance with Table 317.5, Footnote 2 or 3, the building shall be classified by application of ASCE 7, Section 12.3.2. If the evaluation and retrofit is in accordance with ASCE 41, the building shall be classified as irregular when an irregularity defined in ASCE 41, Sections 7.3.1.1.1 through 7.3.1.1.4 exists.
319.6 General selection of the design method. The requirements of Method B (Section 321) may be used for any existing building.
319.7 Prescriptive selection of the design method. The requirements of Method A per Section 320 or the specific procedures for applicable building types given in Section 319.1.1 are permitted to be used except if the building has one or more characteristics described in Sections 319.7.1 through 319.7.7, in which case Method B shall be used.
319.7.1 A building with prestressed or post- tensioned structural components (beams, columns, walls or slabs) or precast structural components (beams, columns, walls or flooring systems).
319.7.2 A building classified as irregular per Section 319.5.
Exceptions: 1. The retrofit design removes the configurational attributes that caused the building to be classified as irregular. 2. The irregularity is demonstrated not to affect the seismic performance of the building.
319.7.3 A building assigned to Risk Category IV per Section 319.4.
319.7.4 A building with an undefined or hybrid structural system.
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319.7.5 A building with a seismic isolation or energy dissipation system, either as part of the existing structure or as part of the retrofit.
319.7.6 A building greater than 240 feet (73 m) in height.
319.7.7 A building evaluated per ASCE 41 and its application requires the use of a nonlinear analysis procedure.
CEBC § 321.2.1 High relevance — show source text
321.2.1 The approach used in the development of the design shall be acceptable to the peer reviewer and the enforcement agency and shall be the same method as used in the evaluation of the building. Approaches that are specifically tailored to the type of building, construction materials and specific building characteristics may be used, if they are acceptable to the independent peer reviewer. The use of Method A allowed procedures may also be used under Method B.
321.2.2 Any method of analysis may be used, subject to acceptance by the peer reviewer(s) and the building official. The general requirements given in ASCE 41, Chapters 6 and 7, shall be complied with unless exceptions are accepted by the peer reviewer(s) and building official. Use of other than ASCE 41 procedures in Method B requires building official concurrence before implementation.
321.2.3 Prior to implementation, the procedures, methods, material assumptions and acceptance/rejection criteria proposed by the registered design professional will be peer reviewed as provided in Section 322. Where nonlinear procedures are used, prior to any analysis, the representation of the seismic ground motion shall be reviewed and approved by the peer reviewer(s) and the building official.
[DSA-SS, DSA-SS/CC] For public school and community college projects, the representation of the seismic ground motion shall be reviewed and approved by the California Geological Survey.
321.2.4 The conclusions and design decisions shall be reviewed and accepted by the peer reviewer(s) and the building official.
SECTION 322 [BSC, DSA-SS & DSA-SS/CC]—PEER REVIEW REQUIREMENTS
322.1 General. Independent peer review is an objective, technical review by knowledgeable reviewer(s) experienced in the structural design, analysis and performance issues involved. The reviewer(s) shall examine the available information on the condition of the building, the basic engineering concepts employed and the recommendations for action.
322.2 Timing of independent review. The independent reviewer(s) shall be selected prior to initiation of substantial portions of the design and/or analysis work that is to be reviewed, and review shall start as soon as practical after Method B is adopted and sufficient information defining the project is available.
322.3 Qualifications and terms of employment. The reviewer(s) shall be independent from the design and construction team.
322.3.1 The reviewer(s) shall have no other involvement in the project before, during or after the review, except in a review capacity.
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322.3.2 The reviewer(s) shall be selected and paid by the owner and shall have technical expertise in the evaluation and retrofit of buildings similar to the one being reviewed, as determined by the enforcement agency.
322.3.3 The reviewer (or in the case of review teams, the chair) shall be a California-licensed structural engineer who is familiar with the technical issues and regulations governing the work to be reviewed.
Exception: Other individuals with acceptable qualifications and experience may be a peer reviewer(s) with the approval of the building official.
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 § 3-20 High relevance — show source text
3-20 2025 CALIFORNIA EXISTING BUILDING CODE
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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.
When the evaluation indicates the building does not meet the required performance levels given in Table 317.5 for the risk category, then a retrofit and/or repair design shall be prepared that provides a structure that meets these performance objectives and reflects the appropriate consideration of existing conditions. Any approach to analysis and design is permitted to be used, provided that the approach shall be rational, shall be consistent with the established principals of mechanics and shall use the known performance characteristics of materials and assemblages under reversing loads typical of severe earthquake ground motions.
Exception: Further consideration of the structure’s seismic performance may be waived by the enforcement agency if both the registered design professional and peer reviewer(s) conclude that the structural system can be expected to perform at least as well as required by the provisions of this section without completing an analysis of the structure’s compliance with these requirements. A detailed report shall be submitted to the responsible building official that presents the reasons and basis for this conclusion. This report shall be prepared by the registered design professional. The peer reviewer(s) shall concur in this conclusion and affirm to it in writing. The building official shall either approve this decision or require completion of the indicated work specified in this section prior to approval.
321.2 The approach, models, analysis procedures, assumptions on material and system behavior and conclusions shall be peer reviewed in accordance with the requirements of Section 322 and accepted by the peer reviewer(s).
Exceptions: 1. The enforcement agency may perform the work of peer review when qualified staff is available within the jurisdiction. 2. The enforcement agency may modify or waive the requirements for peer review when appropriate.
CEBC § 317.5 High relevance — show source text
When the evaluation indicates the building does not meet the required performance levels given in Table 317.5 for the risk category, then a retrofit and/or repair design shall be prepared that provides a structure that meets these performance objectives and reflects the appropriate consideration of existing conditions. Any approach to analysis and design is permitted to be used, provided that the approach shall be rational, shall be consistent with the established principals of mechanics and shall use the known performance characteristics of materials and assemblages under reversing loads typical of severe earthquake ground motions.
Exception: Further consideration of the structure’s seismic performance may be waived by the enforcement agency if both the registered design professional and peer reviewer(s) conclude that the structural system can be expected to perform at least as well as required by the provisions of this section without completing an analysis of the structure’s compliance with these requirements. A detailed report shall be submitted to the responsible building official that presents the reasons and basis for this conclusion. This report shall be prepared by the registered design professional. The peer reviewer(s) shall concur in this conclusion and affirm to it in writing. The building official shall either approve this decision or require completion of the indicated work specified in this section prior to approval.
321.2 The approach, models, analysis procedures, assumptions on material and system behavior and conclusions shall be peer reviewed in accordance with the requirements of Section 322 and accepted by the peer reviewer(s).
Exceptions: 1. The enforcement agency may perform the work of peer review when qualified staff is available within the jurisdiction. 2. The enforcement agency may modify or waive the requirements for peer review when appropriate.
321.2.1 The approach used in the development of the design shall be acceptable to the peer reviewer and the enforcement agency and shall be the same method as used in the evaluation of the building. Approaches that are specifically tailored to the type of building, construction materials and specific building characteristics may be used, if they are acceptable to the independent peer reviewer. The use of Method A allowed procedures may also be used under Method B.
321.2.2 Any method of analysis may be used, subject to acceptance by the peer reviewer(s) and the building official. The general requirements given in ASCE 41, Chapters 6 and 7, shall be complied with unless exceptions are accepted by the peer reviewer(s) and building official. Use of other than ASCE 41 procedures in Method B requires building official concurrence before implementation.
321.2.3 Prior to implementation, the procedures, methods, material assumptions and acceptance/rejection criteria proposed by the registered design professional will be peer reviewed as provided in Section 322. Where nonlinear procedures are used, prior to any analysis, the representation of the seismic ground motion shall be reviewed and approved by the peer reviewer(s) and the building official.
[DSA-SS, DSA-SS/CC] For public school and community college projects, the representation of the seismic ground motion shall be reviewed and approved by the California Geological Survey.
321.2.4 The conclusions and design decisions shall be reviewed and accepted by the peer reviewer(s) and the building official.
SECTION 322 [BSC, DSA-SS & DSA-SS/CC]—PEER REVIEW REQUIREMENTS
CEBC § 3-7 Medium relevance — show source text
312 [OSHPD 1R] Hospital SPC and Freestanding Buildings Removed from General Acute Care Service Remaining under the Jurisdiction of OSHPD . . . . . . . . . . . . . . . . . 3-7
313 [SFM] Existing Group R-1 and Group R-2 Occupancies . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
314 [SFM] Existing High-Rise Buildings . . . . . . . . . . . . . . . .3-11
315 [SFM] Existing Group I Occupancies . . . . . . . . . . . . . . .3-13
316 [SFM] Existing Group L Occupancies. . . . . . . . . . . . . . .3-14
317 [BSC, DSA-SS & DSA-SS/CC] Earthquake Evaluation and Design for Retrofit of Existing Buildings. . . . . . . . . .3-16
318 [BSC, DSA-SS & DSA-SS/CC] Definitions . . . . . . . . . . . .3-18
319 [BSC, DSA-SS & DSA-SS/CC] Seismic Criteria Selection for Existing Buildings . . . . . . . . . . . . . . . . . . . . . . . . . .3-18
320 [BSC, DSA-SS & DSA-SS/CC] Method A. . . . . . . . . . . . . .3-21
321 [BSC, DSA-SS & DSA-SS/CC] Method B. . . . . . . . . . . . . .3-21
322 [BSC, DSA-SS & DSA-SS/CC] Peer Review Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-21
323 [DSA-SS, DSA-SS/CC] Additional Requirements for Public Schools and Community Colleges. . . . . . . . . . . . . . .3-22
CHAPTER 3A [OSHPD 1] PROVISIONS FOR
ALL COMPLIANCE METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . .3A-3
301A Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3A-3
302A General Provisions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3A-3
303A Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3A-4
CEBC § 303.3 Medium relevance — show source text
Exceptions:
- Where an addition is being added on an existing Group E site, and where the addition is not of sufficient size to accommodate the required occupant capacity of the storm shelter for all of the buildings on-site, the storm shelter shall at a minimum accommodate the required capacity for the addition.
- Where approved by the code official, the required design occupant capacity of the shelter shall be permitted to be reduced by the design occupant capacity of any existing storm shelters on the site.
303.3 Occupancy classification. The occupancy classification for storm shelters shall be determined in accordance with Section 423.3 of the California Building Code .
SECTION 304—STRUCTURAL DESIGN LOADS AND EVALUATION AND DESIGN PROCEDURES
[BS] 304.1 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 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 of the California Building Code shall be used.
[BS] 304.2 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.
[BS] 304.3 Seismic evaluation and design procedures. Where required, seismic evaluation or design shall comply with the procedures and criteria in this section, regardless of which compliance method is used. The scope of the required evaluation or design shall be as indicated in applicable provisions of Chapters 4 through 11 .
[BS] 304.3.1 Full seismic criteria. Where required, seismic evaluation or design shall comply with one of the following methodologies, which shall not be applied in combination with each other:
- Section 1613 of the California Building Code . Where the existing seismic force-resisting system is a type that can be designated as “Ordinary,” values of R, Ω 0 and C d used for analysis in accordance with Chapter 16 of the California Building Code shall be those specified for structural systems classified as “Ordinary” in accordance with Table 12.2-1 of ASCE 7, unless it can be demonstrated that the structural system will provide performance equivalent to that of a “Detailed,” “Intermediate” or “Special” system.
- ASCE 41, using a Tier 3 procedure and both levels of the two-level performance objective in Table 304.3.1 for the applicable risk category.
CEBC § 6.2. Medium relevance — show source text
Adjacent structures or site features that may affect the retrofit design shall be identified._
The entire load path of the seismic-force-resisting system shall be determined, documented and evaluated. The load path includes all the horizontal and vertical elements participating in the structural response: such as diaphragms, diaphragm chords, diaphragm collectors, vertical elements such as walls frames, braces; foundations and the connections between the components and elements of the load path. Repaired or retrofitted elements and the standards under which the work was constructed shall be identified.
Data collection in accordance with ASCE 41 shall meet the following minimum levels: 1. [BSC] For state-owned buildings, the requirements shall be met following the data collection requirements of ASCE 41, Section 6.2.
2. [DSA-SS, DSA-SS/CC] For public schools and community college buildings constructed in conformance with the Field Act, visual condition assessment and usual material testing is required unless a more extensive level is required by ASCE 41, Section 6.2.
3. [DSA-SS, DSA-SS/CC] For public schools and community college buildings not constructed in conformance with the Field Act, comprehensive condition assessment and material testing is required, unless a more extensive level is required by ASCE 41, Section 6.2.
Concrete material requirements and testing for public school and community college buildings shall also comply with Sections 1911A and 1909.5 of the California Building Code, respectively.
Qualified test data from the original construction may be accepted, in part or in whole, by the enforcement agency to fulfill the data collection requirements.
Exceptions: 1. The number of samples for data collection may be adjusted with approval of the enforcement agency when it has been determined that adequate information has been obtained or additional information is required. 2. Welded steel moment frame connections of buildings that may have experienced potentially damaging ground motions shall be inspected in accordance with Chapters 3 and 4, FEMA 352, Recommended Post Earthquake Evaluation and Repair Criteria for Welded Moment-Frame Construction for Seismic Applications (July 2000).
Where original building plans and specifications are not available, “as-built” plans shall be prepared that depict the existing vertical and lateral structural systems, exterior elements, foundations and nonstructural systems in sufficient detail to complete the design.
Data collection shall be directed and observed by the project structural engineer or design professional in charge of the design.
319.3 Site geology and soil characteristics. Soil profile shall be assigned in accordance with the requirements of Chapter 18 of the California Building Code.
319.4 Risk categories. Each structure shall be placed in one of the Risk Categories in accordance with the requirements of the California Building Code.
319.5 Configuration requirements. Each structure shall be designated structurally regular or irregular. If the evaluation and retrofit is in accordance with Table 317.5, Footnote 2 or 3, the building shall be classified by application of ASCE 7, Section 12.3.2. If the evaluation and retrofit is in accordance with ASCE 41, the building shall be classified as irregular when an irregularity defined in ASCE 41, Sections 7.3.1.1.1 through 7.3.1.1.4 exists.
319.6 General selection of the design method. The requirements of Method B (Section 321) may be used for any existing building.
CEBC § 317.2 Medium 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 § 319.1 Medium 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.
Frequently asked questions
When is Method B mandatory?
If the building has any characteristic listed in § 319.7 (e.g., prestressed/post‑tensioned or precast components, irregular configuration, Risk Category IV, seismic isolation, height > 240 ft, undefined/hybrid system, or requires nonlinear analysis), Method B is required. § 319.7
Can I use Method B even if Method A is allowed?
Yes. Method B may be used for any existing building, but its analytical approach and assumptions must be accepted by the building official and peer reviewer(s) where required. § 319.6, § 321.2
Does Method B always require peer review?
Yes — Method B requires independent peer review as described in § 319.1 and § 322, unless the enforcement agency performs, modifies, or waives peer review per the limited exceptions in § 321.2. § 319.1, § 321.2, § 322
If my building is irregular but I plan a retrofit that removes the irregularity, can I use Method A?
Yes — there is an exception to § 319.7.2 permitting Method A if the retrofit removes the features that caused the irregularity, or the irregularity can be shown not to affect performance. § 319.7.2 (Exceptions)
Which ASCE 41 procedures apply to Method A?
Method A uses the Linear Static or Linear Dynamic procedures of ASCE 41, Sections 7.4.1 and 7.4.2, and must comply with ASCE 41 Chapters 6 and 7. § 320.1
More in California Existing Building Code
- Administration and Definitions (Scope, enforcement, code official duties, definitions)
- Provisions for All Compliance Methods (general requirements that apply to all compliance options; Chapter 3 / 3A)
- Seismic retrofit and evaluation (Appendix A and seismic provisions/sections for evaluation and retrofit)
- Referenced Standards and Appendices (Chapter 16 and Appendices A–E, Resource A)
- Repairs (Chapter 4 — repair-specific rules for materials, means of egress, structural, MEP, etc.)
- Alterations — Level 1, Level 2, Level 3 (technical requirements for each alteration level; Chapters 7–9)
- Change of Occupancy and Additions (requirements for occupancy changes and additions; Chapters 10–11)
- Compliance Methods — Prescriptive, Work Area, Performance (Chapters 5, 6–11, 13)
- Relocated Buildings (requirements for buildings moved or relocated; Chapter 14)
- Construction Safeguards (site safety, means of egress and life-safety during construction; Chapter 15)
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