CBC · California Building Code

Are peer review or earthquake monitoring requirements applicable for existing building projects?

If your existing building project uses the performance‑based (Method B) seismic approach or proposes alternative lateral systems, the CBC ties peer review to the statewide peer‑review rules (see § 301A.6 → § 1617A.1.41) and allows enforcement agencies to require earthquake recording instruments for selected existing buildings or as a condition of approving alternative LFRS details (see § 301A.7 → § 313A and § 104.2.3.8) .

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

Yes — the California Existing Building Code explicitly ties peer review for existing-building projects to the CBC peer‑review rules and ties earthquake‑monitoring requirements for existing buildings to the Existing Building Code monitoring provisions. Specifically, § 301A.6 says peer review requirements for existing buildings must comply with California Building Code § 1617A.1.41 , and § 301A.7 directs that earthquake monitoring instrumentation for existing buildings comply with Section 313A of the Existing Building Code .

Requirements in detail

Which projects trigger peer review?

The Existing Building Code requires peer review where the applicable sections call for it (for example, Method B seismic evaluations and certain retrofit projects). Method B (the performance-based evaluation approach) and the related peer review rules are in Sections 321 and 322; those sections require independent peer review of the analysis, models and conclusions and make the peer reviewer selection subject to the building official’s approval (§ 321.2 and § 322) .
The statewide CBC peer‑review standard for design projects referenced for existing buildings is § 1617A.1.41 (§ 301A.6 → § 1617A.1.41) .

What does the peer review requirement mean in practice?

Independent reviewers must be independent of the design/construction team, possess appropriate technical expertise, and in many cases the lead reviewer must be a California-licensed structural engineer; reviewers are selected and paid by the owner but approved by the enforcement agency (§ 322 and § 1617A.1.41) .
Peer review timing: reviewers should be selected before substantial design/analysis work begins and must review at schematic, design‑development and construction‑document stages (unless the building official approves waivers) (§ 322.2, § 322.5) .
Reports: the peer reviewer must prepare written reports documenting scope, findings, and conclusions and submit them to the owner and the building official (§ 322.5; § 1617A.1.41 includes required elements for peer‑review reports) .

Which projects trigger earthquake monitoring or instrumentation?

§ 301A.7 points building owners and designers to Section 313A of the Existing Building Code; Section 313A allows the enforcement agency to select existing structures for earthquake recording instrumentation and requires owners to provide space and access for instruments (§ 301A.7 → § 313A) .
Separately, the CBC authorizes the enforcement agency to require earthquake monitoring when an alternative Lateral Force Resisting System (LFRS) is approved; that instrument requirement and minimum expectations (e.g., “sufficient number” of instruments including at least one tri‑axial free‑field instrument) are stated in the CBC administration provisions for alternative systems (§ 104.2.3.8) and in the OSHPD/structural design modifications (§ 1617A.1.39) .

Who is responsible for installation, operation and data?

For enforcement‑selected monitoring under § 313A, the enforcement agency arranges to provide, maintain and service the instruments; owners must provide space and access and (where the code requires) cooperate with the program (§ 313A.1) .
For instrumentation required as a condition of approving an alternate LFRS, the owner is responsible for implementing the instrumentation program and for maintenance/service per § 104.2.3.8; the instrumentation plan must be submitted to the enforcement agency for approval (§ 104.2.3.8) .

Decision‑relevant table

Decision dimension	Typical values / triggers	What the code requires	Code Reference
Whether peer review applies	Method B performance evaluations; projects using alternative methods requiring independent review	Peer review must follow the CBC peer‑review requirements and be approved by the building official; reviewer independence and qualifications required	§ 301A.6 → § 1617A.1.41; §§ 321–322
Reviewer qualifications	California‑licensed structural engineer (typical lead) or equivalent with building‑type experience	Reviewer(s) must be independent, competent, selected/paid by owner, approved by enforcement agency; serve through project completion	§ 1617A.1.41; § 322.3
Reviewer timing	Before substantial design/analysis; schematic → design development → construction docs	Reviewer must be selected prior to substantial design/analysis and provide reports at required phases (exceptions allowed by building official)	§ 1617A.1.41; § 322.2–322.5
Whether monitoring applies	Enforcement agency selection OR approval of an alternative LFRS	Enforcement agency may require instruments for selected existing buildings; alternative LFRS approvals may carry instrumentation conditions	§ 301A.7 → § 313A; § 104.2.3.8; § 1617A.1.39
Minimum instrumentation elements	“Sufficient number” to characterize response; at least one tri‑axial free‑field instrument	At least one tri‑axial free‑field (or equivalent); instruments must have common start/timing, accessible installation; proposal submitted for approval	§ 104.2.3.8; § 1617A.1.39
Ownership / data	Enforcement agency vs. owner responsibilities	For enforcement‑selected 313A installations the enforcement agency provides/maintains instruments and owns data; copies available to public on request. For alternative LFRS cases, owner implements and maintains instrumentation program	§ 313A.1; § 104.2.3.8

Exceptions & special cases

The enforcement agency may perform peer review in‑house when it has qualified staff, or may modify/waive peer review requirements where appropriate (§ 322 exceptions) .
For some OSHPD (hospital) or other agency‑adopted program elements, modified or additional peer‑review scope/requirements apply (see § 1617A.1.41 and cross‑references) — the code includes OSHPD‑specific peer‑review text and additional monitoring/verification rules for certain hospital systems (§ 1617A.1.41 and § 1617A.1.39) .
For state‑owned buildings and some specific retrofit procedures, the Existing Building Code provides alternate specific procedures (Appendix A) that may avoid a full peer review process if the alternate is used; consult § 319.1.1 and the adopting agency rules .

Common mistakes

Assuming peer review is optional for all Method B projects: Method B explicitly requires peer review per §§ 321–322 unless the enforcement agency exercises an allowed exception; check with the building official and follow § 1617A.1.41 for procedural requirements .
Thinking instrumentation applies only to new buildings: the Existing Building Code (§ 313A) allows the enforcement agency to select existing buildings for instruments, and alternative LFRS approvals can require instrumentation per administrative provisions (§ 104.2.3.8) .
Omitting reviewer independence or owner selection responsibilities: the code requires reviewer independence, owner selection/payment, and building‑official approval of the reviewer — these are enforceable procedural requirements (§ 322; § 1617A.1.41) .
Inventing exact instrument counts or sensor layouts without approval: the CBC sets performance/coverage expectations (sufficient to characterize response; at least one tri‑axial free‑field) but leaves the exact plan to the instrumentation proposal and enforcement‑agency approval (§ 104.2.3.8; § 1617A.1.39) .

Worked example — concrete scenario

Scenario: Owner proposes a Method B seismic retrofit for an existing 5‑story office building (Risk Category III). The registered design professional chooses a nonlinear analysis approach and the project is submitted under Method B.

Peer review: Because the project uses Method B, the analysis approach, models and assumptions must be peer‑reviewed per §§ 321–322. The owner selects and pays a peer reviewer who is a California‑licensed structural engineer; the building official must approve the reviewer and the reviewer must begin review before substantial analysis is performed (§ 321.2; § 322.2–322.5; § 1617A.1.41) . The reviewer issues schematic‑phase and design‑development reports and a final report before plan submission (§ 322.5) .
Earthquake monitoring: The design uses an alternative LFRS detail not specifically listed in ASCE 7, and the building official conditions approval on installation of earthquake monitoring instruments. The code requires the owner to implement the instrumentation program and submit an instrumentation proposal for approval; the instrumentation must include at least one tri‑axial free‑field instrument and be sufficient to characterize building response. The owner is responsible for implementation and maintenance per § 104.2.3.8, and the enforcement agency must approve the instrumentation proposal (§ 104.2.3.8; § 1617A.1.39) .

Practical takeaway: the project will need an approved peer reviewer (reports on record) and an instrumentation plan accepted by the enforcement agency before final approval; don’t submit final plans without peer‑review reports and the instrumentation proposal when these are required (§ 322; § 104.2.3.8) .

Related provisions

§ 301A.6 (peer review requirements — see § 1617A.1.41)
§ 301A.7 (earthquake monitoring instruments for existing buildings — see § 313A)
§ 1617A.1.41 (CBC peer review details and report requirements)
§ 313A (Existing Building Code — earthquake recording instrumentation for existing buildings)
§ 104.2.3.8 (CBC — enforcement agency authority to require earthquake monitoring for alternative LFRS approvals)
§§ 321–322 (Existing Building Code Method B and peer review procedures)

Code references

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

CBC § 104.2.3.7 High relevance — show source text
[A] 104.2.3.7 Peer review. The building official is authorized to require submittal of a peer review report in conjunction with a request to use an alternative material, design or method of construction, prepared by a peer reviewer that is approved by the building official.

[OSHPD 1, 1R, 2, 4 & 5] When peer review is required for new or existing buildings, it shall be performed in accordance with Section 1617A.1.41.

104.2.3.8 Earthquake monitoring instruments. [OSHPD 1 & 4] The enforcement agency shall be permitted to require earth- quake monitoring instruments for any building that receives approval of an alternative system for the Lateral Force Resisting System (LFRS). There shall be a sufficient number of instruments to characterize the response of the building during an earth- quake and shall include at least one tri-axial free field instrument or equivalent. A proposal for instrumentation and equipment specifications shall be forwarded to the enforcement agency for review and approval.

The instruments shall be interconnected for common start and common timing. Each instrument shall be located so that access is maintained at all times and is unobstructed by room contents. A sign stating “MAINTAIN CLEAR ACCESS TO THIS INSTRU- MENT” shall be posted in a conspicuous location.

The Owner of the building shall be responsible for the implementation of the instrumentation program. Maintenance and service of the instruments shall be in accordance with Section L101.3 of this code.

[A] 104.2.4 Modifications. Where there are practical difficulties involved in carrying out the provisions of this code, the building official shall have the authority to grant modifications for individual cases, provided that the building official shall first find that one or more special individual reasons make the strict letter of this code impractical, and that the modification is in compliance with the intent and purpose of this code and that such modification does not lessen health, accessibility, life and fire safety or structural requirements. The details of the written request for and action granting modifications shall be recorded and entered in the files of the department of building safety.

[A] 104.2.4.1 Flood hazard areas. The building official shall not grant modifications to any provision required in flood hazard areas as established by Section 1612.3 unless a determination has been made that:
1. A showing of good and sufficient cause that the unique characteristics of the size, configuration or topography of the site render the elevation standards of Section 1612 inappropriate.
2. A determination that failure to grant the variance would result in exceptional hardship by rendering the lot undevelopable.
3. A determination that the granting of a variance will not result in increased flood heights, additional threats to public safety or extraordinary public expense; cause fraud on or victimization of the public; or conflict with existing laws or ordinances.
4. A determination that the variance is the minimum necessary to afford relief, considering the flood hazard.
5. Submission to the applicant of written notice specifying 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 commensurate with the increased risk resulting from the reduced floor elevation, and stating that construction below the design flood elevation increases risks to life and property.
[A] 104.3 Applications and permits. The building 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.
CBC § 3.2 High relevance — show source text
301 A .3.2 Nonconforming buildings . Alterations, additions and changes of occupancy to existing buildings or structures designed in accordance with the Pre-1973 building code complying with Section 304A.3.1 and the applicable requirements herein shall be considered in compliance with the provisions of this code.

301 A .3.3 Performance- based method. Alterations, additions and changes of occupancy to existing buildings or structures complying with Sections 304A.3.4 and 304A.3.5 of this code shall be considered in compliance with the provisions of this code.

301 A .4 Moved structures . Structures moved into or within the jurisdiction shall comply with the provisions of the California Building Code for new structures.

301A.5 Reserved.

301A.6 Peer review requirements. Peer review requirements shall comply with California Building Code Section 1617A.1.41.

301A.7 Earthquake monitoring instruments for existing buildings. Earthquake monitoring instrumentation of existing buildings shall comply with Section 313A.

301A.8 Compliance alternatives for services/systems and utilities . Compliance alternatives for services/systems and utilities shall comply with Section 310A.

301A.9 Compliance alternatives for means of egress. Means of egress through existing buildings shall comply with Section 311A.

301A.10 Removal of hospital buildings from general acute care services. Removal of hospital buildings from General Acute Care Services shall comply with Section 312A.

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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CBC § 1-25 High relevance — show source text
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[A] 104.2.3.5.1 Fire Tests. Tests conducted to demonstrate equivalent fire safety in support of an alternative material, design or method of construction application shall be of a scale that is sufficient to predict fire safety performance of the end use configuration. Tests shall be performed by a party acceptable to the building official.

[A] 104.2.3.6 Reports. Supporting data, where necessary to assist in the approval of materials or assemblies not specifically provided for in this code, shall comply with Sections 104.2.3.6.1 and 104.2.3.6.2.

[A] 104.2.3.6.1 Evaluation reports. Evaluation reports shall be issued by an approved agency and use of the evaluation report shall require approval by the building official for the installation. The alternate material, design or method of construction and product evaluated shall be within the scope of the building official’s recognition of the approved agency. Criteria used for the evaluation shall be identified within the report and, where required, provided to the building official.

[A] 104.2.3.6.2 Other reports. Reports not complying with Section 104.2.3.6.1 shall describe criteria, including but not limited to any referenced testing or analysis, used to determine compliance with code intent and justify code equivalence. The report shall be prepared by a qualified engineer, specialist, laboratory or specialty organization acceptable to the building official. The building official is authorized to require design submittals to be prepared by, and bear the stamp of, a registered design professional.

[A] 104.2.3.7 Peer review. The building official is authorized to require submittal of a peer review report in conjunction with a request to use an alternative material, design or method of construction, prepared by a peer reviewer that is approved by the building official.

[OSHPD 1, 1R, 2, 4 & 5] When peer review is required for new or existing buildings, it shall be performed in accordance with Section 1617A.1.41.

104.2.3.8 Earthquake monitoring instruments. [OSHPD 1 & 4] The enforcement agency shall be permitted to require earth- quake monitoring instruments for any building that receives approval of an alternative system for the Lateral Force Resisting System (LFRS). There shall be a sufficient number of instruments to characterize the response of the building during an earth- quake and shall include at least one tri-axial free field instrument or equivalent. A proposal for instrumentation and equipment specifications shall be forwarded to the enforcement agency for review and approval.

The instruments shall be interconnected for common start and common timing. Each instrument shall be located so that access is maintained at all times and is unobstructed by room contents. A sign stating “MAINTAIN CLEAR ACCESS TO THIS INSTRU- MENT” shall be posted in a conspicuous location.

The Owner of the building shall be responsible for the implementation of the instrumentation program. Maintenance and service of the instruments shall be in accordance with Section L101.3 of this code.
CBC § 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
CBC § 3-20 High relevance — show source text
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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.
CBC § 1.1 High relevance — show source text
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.

301 A .3.2 Nonconforming buildings . Alterations, additions and changes of occupancy to existing buildings or structures designed in accordance with the Pre-1973 building code complying with Section 304A.3.1 and the applicable requirements herein shall be considered in compliance with the provisions of this code.

301 A .3.3 Performance- based method. Alterations, additions and changes of occupancy to existing buildings or structures complying with Sections 304A.3.4 and 304A.3.5 of this code shall be considered in compliance with the provisions of this code.

301 A .4 Moved structures . Structures moved into or within the jurisdiction shall comply with the provisions of the California Building Code for new structures.

301A.5 Reserved.

301A.6 Peer review requirements. Peer review requirements shall comply with California Building Code Section 1617A.1.41.

301A.7 Earthquake monitoring instruments for existing buildings. Earthquake monitoring instrumentation of existing buildings shall comply with Section 313A.

301A.8 Compliance alternatives for services/systems and utilities . Compliance alternatives for services/systems and utilities shall comply with Section 310A.

301A.9 Compliance alternatives for means of egress. Means of egress through existing buildings shall comply with Section 311A.

301A.10 Removal of hospital buildings from general acute care services. Removal of hospital buildings from General Acute Care Services shall comply with Section 312A.
CBC § 104.2.3.6.2 High relevance — show source text
[A] 104.2.3.6.2 Other reports. Reports not complying with Section 104.2.3.6.1 shall describe criteria, including but not limited to any referenced testing or analysis, used to determine compliance with code intent and justify code equivalence. The report shall be prepared by a qualified engineer, specialist, laboratory or fire safety specialty organization acceptable to the code official. The code official is authorized to require design submittals to be prepared by, and bear the stamp of, a registered design professional.

[A] 104.2.3.7 Peer review. The code official is authorized to require submittal of a peer review report in conjunction with a request to use an alternative material, design or method of construction, prepared by a peer reviewer that is approved by the code official.

[A] 104.2.4 Modifications. Where there are practical difficulties involved in carrying out the provisions of this code, the code official shall have the authority to grant modifications for individual cases, provided that the code official shall first find that one or more special individual reasons make the strict letter of this code impractical, and that the modification is in compliance with the intent and purpose of this code and that such modification does not lessen health, accessibility, life and fire safety, or structural requirements. The details of the written request for and action granting modifications shall be recorded and entered in the files of the department of building safety.

[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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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.
CBC § 1617A.1.40 High relevance — show source text
Where the detailed joint evaluation report is not submitted within the timeframes specified above, the building shall not be issued a building permit for any projects except for those for seismic compliance, maintenance and repair until the detailed joint evaluation work is complete.

1617A.1.40 Operational nonstructural performance level requirements. [OSHPD 1 & 4] New general acute care hospitals and new building(s) required for general acute care services shall satisfy Operational Nonstructural Performance Level (NPC-5) requirements.

Exception: A new building which is required for general acute care services that is added to an existing general acute care hospital and which has a building area of 4,000 square feet (371 m [2] ) or less, need not satisfy the NPC-5 requirements until the deadline speci- fied in California Administrative Code (Part 1, Title 24 CCR), Chapter 6.

Hospitals and buildings designed and constructed to the provisions of this code for new construction shall be deemed to satisfy Operational Nonstructural Performance Level (NPC-5) requirements when: 1. The facility has on-site supplies of water and holding tanks for sewage and liquid waste, sufficient to support 72 hours of emergency operations for the hospital or building, which are integrated into the building plumbing systems in accordance with the California Plumbing Code. 2. An on-site emergency system as defined in the California Electrical Code is incorporated into the building electrical system for critical care areas. Additionally, the system shall provide for radiological service and an onsite fuel supply for 72 hours of acute care operation.

Emergency and standby generators shall not be located below the higher of the Design Flood Elevation (DFE) or Base Flood Eleva- tion (BFE) plus two feet (BFE + 2 ft.) or 500 year flood elevation, whichever is higher, and shall be located at an elevation close to grade for easy accessibility from outside for maintenance.

1617A.1.41 Peer Review Requirements. [OSHPD 1, 1R, 2 & 5] 1. General. Independent peer review is an objective technical review by knowledgeable reviewer(s) experienced in structural design, analysis and performance issues involved. The reviewer(s) shall examine the available information on the condition of the building, basic engineering concept employed and recommendations for action. Exception: OSHPD may perform the work of peer review when qualified staff is available. 2. Timing of Independent Review. The independent reviewer (s) shall be selected prior to initiation of substantial portion of the design and analysis work that is to be reviewed, and review shall start as soon as practical and sufficient information defining the project is available. 3. Qualifications and Terms of Employment. The reviewer shall be independent from the design and construction team. 3.1. The reviewer(s) shall have no other involvement in the project before, during or after the review, except in a review capacity. 3.2. The reviewer shall be selected and paid by owner and shall have technical expertise similar to the project being reviewed, as determined by enforcement agent. 3.3. The reviewer (in case of review team, the chair) shall be a California-licensed structural engineer who is familiar with technical issues and regulations governing the work to be reviewed. 3.4. The reviewer shall serve through completion of the project and shall not be terminated except for failure to perform _the duties specified herein.
CBC § 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.
CBC § 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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PROVISIONS FOR ALL COMPLIANCE METHODS

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.
CBC § 5.2 High relevance — show source text
The design report shall address the following:
1. Project scope.
2. Goals and objectives.
3. Performance criteria.
4. Hazard scenarios.
5. Design fire loads and hazards.
6. Final design.
7. Evaluation.
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APPENDIX O—PERFORMANCE-BASED APPLICATION
1. Bounding conditions and critical design assumptions.
2. Critical design features.
3. System design and operational requirements.
4. Operational and maintenance requirements.
5. Commissioning testing requirements and acceptance criteria.
6. Frequency of certificate renewal.
7. Supporting documents and references.
8. Preliminary site and floor plans.
O101.5.2 Design submittal. Applicable construction documents shall be submitted to the building official for review. The documents shall be submitted in accordance with the jurisdiction’s procedures and in sufficient detail to obtain appropriate permits.

O101.6 Review. Construction documents submitted in accordance with this code shall be reviewed for code compliance with the appropriate code provisions.

O101.6.1 Peer review. The owner or the owner’s authorized agent shall be responsible for retaining and furnishing the services of a registered design professional or recognized expert, who will perform as a peer reviewer, where required and approved by the building official.

O101.6.2 Costs. The costs of special services, including contract review, where required by the building official, shall be borne by the owner or the owner’s authorized agent.

O101.7 Permits. Prior to the start of construction, appropriate permits shall be obtained in accordance with the jurisdiction’s procedures and applicable codes.

O101.8 Verification of compliance. Upon completion of the project, documentation shall be prepared that verifies performance and prescriptive code provisions have been met. Where required by the building official, the registered design professional shall file a report that verifies bounding conditions are met.

O101.9 Extent of documentation. Approved construction documents, the operations and maintenance manual, inspection and testing records, and certificates of occupancy with conditions shall be included in the project documentation of the building official’s records.

O101.10 Analysis of change. The registered design professional shall evaluate the existing building, facilities, premises, processes, and contents, and the applicable documentation of the proposed change as it affects portions of the building, facility, premises, processes and contents that were previously designed for compliance under a performance-based code. Prior to any change that was not documented in a previously approved design, the registered design professional shall examine the applicable design documents, bounding conditions, operation and maintenance manuals, and deed restrictions.

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APPENDIX O-4 2025 CALIFORNIA BUILDING CODE

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CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

APPENDIX P – SLEEPING LOFTS

(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CBC § 31F-4 High relevance — show source text
The peer reviewer(s) and their affiliated organization shall have no other involvement in the project, except in a review capacity. The peer reviewer(s) shall be a California registered engineer(s) familiar with regulations governing the work and have technical expertise in the subject matter to a degree of at least that needed for the original work. The peer reviewer(s)’ credentials shall be presented to the Division for approval prior to commencement of the review.

Upon completion of the review process, the peer reviewer(s) shall submit a written report directly to the Division that covers all aspects of the review process, including, but not limited to: 1. Scope, extent and limitations of the review. 2. Status of the documents reviewed at each stage (i.e. revision number and date). 3. Findings. 4. Recommended corrective actions and resolutions, if necessary.

5. Conclusions.

6. Certification by the peer reviewer(s), including whether or not the final reviewed work meets the requirements of this code.

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MARINE OIL TERMINALS

7. Formal documentation of important peer review correspondence, including requests for information and written responses.

The owner and operator shall cooperate in the review process, but shall not influence the peer review. If the original work requires modification after completion of the peer review, the final analyses and designs shall be submitted to the Division.

3101F.8.3 Division review. The following will be subject to review for compliance with this code by the Division or its authorized representative(s): 1. Any audit, inspection, analysis or evaluation of MOTs. 2. Any significant change, modification or re-design of a structural, mooring, fire, piping/pipelines, mechanical or electrical system at an MOT, prior to use or reuse. 3. Engineering analysis and design for any new MOT prior to construction. Also see Section 3102F.3.3.1. 4. Construction inspection team and the construction inspection report(s).

3101F.9 Alternatives. In special circumstances where certain requirements of these standards cannot be met, alternatives that provide an equal or better protection of the public health, safety and the environment shall be subject to Division Chief approval with concur- rence of the Division’s lead engineer in responsible charge.

3101F.10 Symbols.

DWT = Dead weight tonnage

Q C = Maximum cargo transfer rate [bbl/hr]

V F = Flowing volume of potential exposed oil [bbl]

V S = Stored volume of potential exposed oil [bbl]

V T = Total volume of potential exposed oil [bbl]

Δ t = ESD closure and activation time (if applicable) [sec]

3101F.11 References.

[1.1] Center for Chemical Process Safety (CCPS), 2008, “Guidelines for Hazard Evaluation Procedures”, 3 [rd] ed., New York.

[1.2] California Code of Regulations (CCR), Title 14, Division 1, Chapter 3, Oil Spill Contingency Plans (14 CCR 815.01 through 818.03), Section 817.02(c)(1) – Risk and Hazard Analysis.

Frequently asked questions

Do §§ 301A.6 and 301A.7 automatically impose peer review and monitoring on every existing‑building project?

No. § 301A.6 and § 301A.7 establish the linkage: peer review and monitoring apply when other code sections or the enforcement agency require them (for example, Method B projects trigger peer review; enforcement agencies select buildings for § 313A instrumentation or attach instrumentation to alternate‑system approvals) .

Who approves the peer reviewer and who pays?

The reviewer is selected and paid by the owner but must be acceptable to and approved by the building official; reviewer independence and qualifications are required by the code (§ 322; § 1617A.1.41) .

If the enforcement agency selects my building for instruments under § 313A, who owns the data?

For enforcement‑selected § 313A installations, the enforcement agency provides, maintains and services the instruments and the data are the property of the enforcement agency; copies of records are available to the public on request and payment of an appropriate fee (§ 313A.1) .

Can the enforcement agency waive peer review or monitoring?

Yes — the code allows the enforcement agency to perform peer review in‑house (if qualified staff exist) or to modify/waive peer review requirements where appropriate; monitoring requirements tied to alternative system approvals may be imposed or tailored by the enforcement agency on a project‑by‑project basis (§ 322 exceptions; § 104.2.3.8) .

What is the minimum instrumentation the code mentions?

The CBC requires instrumentation to be “sufficient to characterize the response of the building” and to include at least one tri‑axial free‑field instrument or equivalent; exact sensor counts and locations are determined in the instrumentation proposal and by the enforcement agency’s approval (§ 104.2.3.8; § 1617A.1.39) .

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