Seismic Evaluation & Retrofit for Existing Buildings

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

• CBC § 0.91 High relevance — show source text

  Fourth, fifth_
  and sixth floors and the second and third basement floor level quantity shall be reduced to 75 percent of this table. The seventh through 10th floor and below the third basement
  floor level quantity shall be reduced to 50 percent of this table.
  2. Permitted only when stored or used in approved exhausted gas cabinets, exhausted enclosures or fume hoods. Quantities of high toxics in use in open systems need not be reduced
  above the third floor or below the first basement floor level. Individual container size shall be limited to 2 pounds (0.91 kg) for solids and1/4 gallon (0.95 L) for liquids.|

  SECTION 317 [BSC, DSA-SS & DSA-SS/CC]—EARTHQUAKE EVALUATION AND DESIGN FOR RETROFIT OF EXISTING BUILDINGS

  317.1 Purpose.

  317.1.1 Existing state-owned structures. [BSC] The provisions of Sections 317 through 322 establish minimum standards for earthquake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California and the California State University.

  The provisions of Sections 317 through 323 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings.

  317.1.2 Public school buildings. [DSA-SS] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as public school buildings under the jurisdiction of the Division of the State Architect—Structural Safety [DSA-SS], refer to Section 1.9.2.1.

  The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public buildings currently under the jurisdiction of DSA-SS.

  317.1.2.1 Reference to other chapters. For public schools, where reference within this chapter is made to sections in Chapters 16, 17, 18, 19, 21 or 22 of the California Building Code, the provisions in Chapters 16A, 17A, 18A, 19A, 21A and 22A of the California Building Code, respectively, shall apply instead.

  317.1.3 Community college buildings. [DSA-SS/CC] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as community college buildings under the jurisdiction of the Division of the State Architect—Structural Safety/Community Colleges [DSA-SS/CC], refer to Section 1.9.2.2.

  The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing community college buildings currently under the jurisdiction of DSA-SS/CC.

  317.1.3.1 Reference to other chapters. For community colleges, where reference within this chapter is made to sections in Chapters 17 or 18 of the California Building Code, the provisions in Chapters 17A and 18A of the California Building Code, respectively, shall apply instead.

• 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 § 12.3 High relevance — show source text

  APPENDIX A—GUIDELINES FOR THE SEISMIC RETROFIT OF EXISTING BUILDINGS

  2. For structures assigned to Seismic Design Category C or D, values of R, Ω 0 and C d shall be permitted to be based on the seismic force-resisting system being used to achieve the required strengthening, provided that when the strengthening is complete, the strengthened structure will not have an extreme weak story irregularity defined as Type 5b in ASCE 7, Table 12.3-2.

  3. For structures assigned to Seismic Design Category E, values of R, Ω 0 and C d shall be permitted to be based on the seismic force-resisting system being used to achieve the required strengthening, provided that when the strengthening is complete, the strengthened structure will not have an extreme soft story, a weak story, or an extreme weak story irregularity defined, respectively, as Types 1b, 5a and 5b in ASCE 7, Table 12.3-2.

  4. For retrofit systems involving different seismic force-resisting systems in the same direction within the same story, resisting elements are permitted to be designed using the least value of R for the different structural systems found in each independent line of resistance if all of the following conditions are met: 4.1. The building is assigned to Risk Category I or II. 4.2. The building height is no more than four stories above grade plane. 4.3. The seismic force-resisting systems of the retrofitted building comprise only wood structural panel shear walls, steel moment-resisting frames, steel cantilever columns and steel-braced frames. Values for C and Ω 0 shall be consistent with the R value used.

  5. With reference to ASCE 7, Table 12.2-1, ordinary, intermediate and special steel systems, and all light-frame systems shall be permitted without limitation where those systems are used only for retrofit to comply with the requirements of this chapter.

  [BS] A403.3.1 Expected story strength. Despite any other requirement of Section A403.3 or A403.4, the total expected strength of retrofit elements added to any story need not exceed 1.7 times the expected strength of the story immediately above in a twostory building, or 1.3 times the expected strength of the story immediately above in a three-story or taller building, as long as the retrofit elements are located symmetrically about the center of mass of the story above, or so as to minimize torsion in the retrofitted story. Calculation of expected story strength and identification of irregularities in Section A403.3 shall be based on the expected strength of all wall lines, even if sheathed with nonconforming materials. The strength of a wall line above the retrofitted story shall be permitted to be reduced to account for inadequate load path or overturning resistance.

  [BS] A403.3.2 Seismicity parameters, site class and geologic hazards. For any site designated as Site Class E, the value of F shall be taken as 1.2. Site-specific procedures are not required for compliance with this chapter. Mitigation of existing geologic site hazards such as liquefiable soil, fault rupture or landslide is not required for compliance with this chapter.

• CBC § 1.10.1 High relevance — show source text

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

  CALIFORNIA BUILDING CODE CORRELATED TOPICS

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

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

  Chapter 1 Scope and Administration.

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

  Chapter 2 Definitions.

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

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  Chapter 3 Provisions for All Compliance Methods.

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

  Chapter 3A Provisions for All Compliance Methods.

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

  Chapter 4 Repairs.

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

  Chapter 4A Repairs.

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

• CBC § 317.1.2.1 High relevance — show source text

  The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public buildings currently under the jurisdiction of DSA-SS.

  317.1.2.1 Reference to other chapters. For public schools, where reference within this chapter is made to sections in Chapters 16, 17, 18, 19, 21 or 22 of the California Building Code, the provisions in Chapters 16A, 17A, 18A, 19A, 21A and 22A of the California Building Code, respectively, shall apply instead.

  317.1.3 Community college buildings. [DSA-SS/CC] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as community college buildings under the jurisdiction of the Division of the State Architect—Structural Safety/Community Colleges [DSA-SS/CC], refer to Section 1.9.2.2.

  The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing community college buildings currently under the jurisdiction of DSA-SS/CC.

  317.1.3.1 Reference to other chapters. For community colleges, where reference within this chapter is made to sections in Chapters 17 or 18 of the California Building Code, the provisions in Chapters 17A and 18A of the California Building Code, respectively, shall apply instead.

  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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  PROVISIONS FOR ALL COMPLIANCE METHODS

• CBC § 304.2 High relevance — show source text

  [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:

  1. 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.
  2. 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.

  [BS] TABLE 304.3.1—PERFORMANCE OBJECTIVES FOR USE IN ASCE 41 FOR COMPLIANCE WITH FULL SEISMIC CRITERIA	Col2	Col3
  RISK CATEGORY (Based on IBC Table 1604.5)	STRUCTURAL PERFORMANCE LEVEL FOR USE WITH BSE-1N EARTHQUAKE HAZARD LEVEL	STRUCTURAL PERFORMANCE LEVEL FOR USE WITH BSE-2N EARTHQUAKE HAZARD LEVEL
  I	Life Safety (S-3)	Collapse Prevention (S-5)
  II	Life Safety (S-3)	Collapse Prevention (S-5)
  III	Damage Control (S-2)	Limited Safety (S-4)
  IV	Immediate Occupancy (S-1)	Life Safety (S-3)

  [BS] 304.3.2 Reduced 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:

  1. Section 1613 of the California Building Code using 75 percent of the prescribed forces. Values of R, Ω 0 and C d used for analysis shall be as specified in Section 304.3.1 of this code.

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  PROVISIONS FOR ALL COMPLIANCE METHODS

  2. Applicable chapters of Appendix A of this code, for structures or portions of structures specified in Items 2.1 through 2.4 subject to the limitations of the respective chapter. 2.1. Chapter A1 for unreinforced masonry bearing wall buildings assigned to Risk Category I or II. 2.2. Chapter A2 for the wall anchorage system in reinforced concrete and reinforced masonry wall buildings with flexible diaphragms assigned to Risk Category I or II.
• CBC § 503.12 High relevance — show source text

  7—2016 with Supplement 1: Minimum Design Loads and Associated Criteria for Buildings and Other Structures [OSHPD 1] with Supplement 3

  503.12, 706.3.2

  7—2022: Minimum Design Loads and Associated Criteria for Buildings and Other Structures [OSHPD 1, 1R, 2, 4 and 5, DSS-SS, DSA- SS/CC] with Supplement 1

  304.2, 304.3.1, 304A.2, 304A.3.6.4, 304A.3.6.6, 503.4, 503.12, 503.13, 501A.3, 502A.5, 503A.4, 503A.13, 706.3.2, 805.3, 805.4

  41— 2013 : [OSHPD 1] Seismic Evaluation and Retrofit of Existing Buildings 304.3.1, Table 304.3.1, 304.3.2, Table 304.3.2, 503.5, 503.11, 506.5.3, 906.2, 906.3, 1006.3

  41—2017: Seismic Evaluation and Retrofit of Existing Buildings 304.3.1, Table 304.3.1, 304.3.2, Table 304.3.2, 503.5, 503.11, 506.5.3, 906.2, 906.3, 1006.3

  41— 2023 : [BSC, DSA-SS, DSA-SS/CC, HCD, OSHPD 1, 1R, 2, 4 and 5] Seismic Evaluation and Retrofit of Existing Buildings 304.3.1, Table 304.3.1, 304.3.2, Table 304.3.2, 317.5, Table 317.5, 317.8, 318.1, 319.1, 319.2, 319.5, 319.7.7, 319.8, 319.9, 319.12, 320.1, 321.2.2, 304A.3.4, 304A.3.6, 503.5, 503.11, 506.5.3, 506A.5.3, 906.2, 906.3, 1006.3

  ASHRAE ASHRAE, 180 Technology Parkway, Peachtree Corners, GA 30092

  62.1—2022: Ventilation for Acceptable Indoor Air Quality

  807.2

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  REFERENCED STANDARDS

  ASME American Society of Mechanical Engineers, Two Park Avenue, New York, NY 10016

  A17.1—2022/CSA B44—2022: Safety Code for Elevators and Escalators

  306.7.7, 306.7.8, 902.1.2

  A17.3—2023: Safety Code for Existing Elevators and Escalators

  902.1.2

• CBC § 3-4 Medium relevance — show source text

  303 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

  304 Structural Design Loads and Evaluation and Design Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

  305 In-Situ Load Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

  306 Accessibility for Existing Buildings . . . . . . . . . . . . . . . 3-6

  307 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

  308 Carbon Monoxide Detection . . . . . . . . . . . . . . . . . . . . . 3-6

  309 Additions and Replacements of Exterior Wall Coverings and Exterior Wall Envelopes . . . . . . . . . 3-7

  310 [OSHPD 1R, 2 and 5] Services/Systems and Utilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

  311 [OSHPD 1R, 2 and 5] Means of Egress . . . . . . . . . . . . . . . 3-7

  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

• CBC § 102.4 Medium relevance — show source text

  Chapter 14 is applicable to any building that is moved or relocated. This chapter is independent of any of the three compliance methods and focuses on the structural loads where the building is being relocated.

  Chapter 15 Construction Safeguards.

  Chapter 15 establishes specific regulations in order to minimize the risk to the public and adjacent property during construction. Additionally, this chapter addresses fire and life safety and means of egress during the construction process. This includes requirements for a site safety plan. This chapter is also consistent with Chapter 33 of the CBC and Chapter 33 of the California Fire Code (CFC).

  Chapter 16 Referenced Standards.

  Chapter 16 lists all of the product and installation standards and codes that are referenced throughout Chapters 1 through 15 and includes identification of the promulgators and the section numbers in which the standards and codes are referenced. As stated in Section 102.4, these standards and codes become an enforceable part of the code (to the prescribed extent of the reference) as if printed in the body of the code.

  Appendix A Guidelines for the Seismic Retrofit of Existing Buildings.

  Appendix A provides guidelines for upgrading the seismic resistance capacity of different types of existing buildings. It is organized into separate chapters which deal with buildings of different types, including unreinforced masonry buildings, reinforced concrete and reinforced masonry wall buildings, and lightframe wood buildings. This appendix includes its own referenced standards.

  Appendix B Supplementary Accessibility Requirements for Existing Buildings and Facilities.

  Chapters 11A and 11B of the CBC contain provisions that set forth requirements for accessibility to buildings and their associated sites and facilities for people with physical disabilities. Appendix B was added to address accessibility in construction for items that are not typically enforceable through the traditional building code enforcement process.

  Appendix C Guidelines for the Wind Retrofit of Existing Buildings.

  The purpose of Appendix C is to provide voluntary prescriptive alternatives for addressing the retrofit of buildings in high-wind areas. Currently, there are two chapters which deal with the retrofit of gable ends and the fastening of roof decks, Appendix Chapters C1 and C2, respectively. This appendix includes its own referenced standards.

  Appendix D Board of Appeals.

  Appendix D contains the provisions for appeal and the establishment of a board of appeals. The provisions include the application for an appeal, the makeup of the board of appeals and the conduct of the appeal process.

  Appendix E Temporary Emergency Uses.

  Appendix E is intended to provide guidance for designers, engineers, architects and fire and building officials on allowing temporary emergency uses of existing buildings with respect to the minimum code requirements. This appendix is a template or checklist that references the relevant code requirement of concerns.

  Resource A Guidelines on Fire Ratings of Archaic Materials and Assemblies.

  In the process of repair and alteration of existing buildings, based on the nature and the extent of the work, the CEBC might require certain upgrades in the fire-resistance rating of building elements, at which time it becomes critical for the designers and the code

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  officials to be able to determine the fire-resistance rating of the existing building elements as part of the overall evaluation for the assessment of the need for improvements. These guidelines are based upon the Guideline on Fire Ratings of Archaic Materials published by the National Institute of Building Sciences (NIBS).

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• CBC § 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.

• CBC § 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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  PROVISIONS FOR ALL COMPLIANCE METHODS

  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.

• CBC § 319.8. Medium 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.”

  3-20 2025 CALIFORNIA EXISTING BUILDING CODE

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

  PROVISIONS FOR ALL COMPLIANCE METHODS

  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.