CEBC · California Existing Building Code
Which compliance method applies to my project?
For an alteration you must follow one of three CEBC methods: Prescriptive (Chapter 5, § 301.3.1), Work Area (Chapters 6–12, § 301.3.2) or Performance (Chapter 13, § 301.3.3). Pick the chapter that matches the type and size of work, watch the 50% area triggers in the Work Area method, and check with the enforcing agency before combining methods or relying on special agency exceptions.
Last reviewed: July 6, 2026
What the code requires — plain English
The California Existing Building Code gives three mutually exclusive compliance choices for alterations, additions, and changes of occupancy: the Prescriptive Compliance Method (use Chapter 5), the Work Area Compliance Method (use Chapters 6–12) and the Performance Compliance Method (use Chapter 13). Choose one method and follow that chapter’s requirements — those projects “complying with Chapter X shall be considered in compliance with this code.” See § 301.3.1, § 301.3.2 and § 301.3.3 for the controlling statements.
The single most important rule: for an alteration/addition/change of occupancy you must comply with one of the three CEBC methods — Prescriptive (Ch.5), Work Area (Ch.6–12) or Performance (Ch.13) — and follow that chapter’s procedures.
Requirements in detail
The three methods (short)
- Prescriptive Compliance Method — follow Chapter 5; used where work can be handled by the prescriptive rules in that chapter. See § 301.3.1.
- Work Area Compliance Method — follow Chapters 6–12; the work is evaluated by classification and level (Level 1, 2 or 3) and applicable requirements are applied to the work area. See § 301.3.2.
- Performance Compliance Method — follow Chapter 13; an evaluation/score‑based, performance approach where the building is shown to meet safety objectives. See § 301.3.3.
Decision table — which method to pick
| Decision factor | Typical value / threshold | Which method applies | Code Reference |
|---|---|---|---|
| Scope of work | Simple replacement/finishes only (no reconfiguration) | Prescriptive (Chapter 5) or Work Area Level 1 | § 301.3.1; Ch.5 / Ch.7 |
| Space reconfiguration | Reconfigurations up to 50% of building area | Work Area (Level 2) — Chapters 6–12 | § 301.3.2; Level 2 (≤ 50%) |
| Large/major alteration | Alterations covering 50% (aggregate) of the building | Work Area (Level 3) — Chapters 6–12 | Ch.9 (Level 3) and § 301.3.2 |
| Where numerical performance demonstration is preferred/required | Owner/designer chooses performance evaluation (score or detailed analysis) | Performance (Chapter 13) | § 301.3.3; Ch.13 |
| Regulated building types (state OSHPD/HCD differences) | Hospitals, OSHPD-regulated facilities or where a state agency limits adoption | See Chapter 3A / Chapter 5A variations or local adoption notes | Notes in § 301.3.1–§ 301.3.3 and Chapter 3A |
Notes on thresholds: the 50% area thresholds and Level definitions (Level 1 / Level 2 / Level 3) are described within the Work Area chapters and chapter synopses (see Chapters 6–9). Use the Work Area chapters to determine exact classification and thresholds for your work.
Exceptions & special cases
- The three methods shall not be applied in combination except where the enforcement agency permits it — you normally pick one method for the project. See § 301.3.1–§ 301.3.3 and the administration notes.
- Some hospital/OSHPD situations are handled by specialized Chapters (3A, 5A) and exceptions — Chapter 13 may not be adopted by certain state agencies (HCD notes); check Chapter 3A/5A and the agency rules. See § 301.3.1 and the note on Chapter 13 adoption.
- All repairs are governed separately by Chapter 4 (repairs chapter) — repairs are not decided by Chapters 5/6/13 choices. See Chapter 4 references.
- Under limited conditions, an alteration may comply with the laws in effect when the building was originally built (subject to accessibility, lack of substantial structural damage, limited structural alterations and approval by the enforcement agency). If relying on that pathway, confirm the specific conditions in the code and with your enforcement agency.
Common mistakes
- Choosing a method by preference without checking the Work Area thresholds (e.g., treating a 50% alteration as Level 2 when it actually reaches the Level 3 trigger). Always verify Level triggers in Chapters 6–9.
- Failing to confirm whether Chapter 13 (Performance) is permitted by the enforcing state agency (some agencies do not adopt Chapter 13). Check Chapter 3A / local adoption notes.
- Trying to mix requirements from multiple compliance methods when the enforcement agency has not approved that combination. The code says methods are not to be combined except when permitted.
- Overlooking that repairs are handled separately in Chapter 4 — small “repair” work is not the same compliance process as an alteration under Ch.5/6/13.
Worked example — concrete scenario
Project: a 5,000 ft² commercial office (single tenant) where the owner will remove and reconfigure interior partitions and upgrade finishes in an area of 1,600 ft².
Step 1 — calculate percent of building affected: 1,600 / 5,000 = 32% of the building area.
Step 2 — compare to Work Area thresholds: because the work area is greater than a small replacement but less than 50%, this matches a Level 2 alteration under the Work Area Compliance Method. See Chapters 6–8 (Work Area Method) and the Level 2 description.
Conclusion: Use the Work Area Compliance Method (Chapters 6–12) and follow Level 2 technical requirements (means of egress, fire protection, structural triggers, energy and building systems as required by those chapters). Cite § 301.3.2 as the controlling code direction.
(If instead the work had been only replacement of finishes with no reconfiguration — Level 1 — a prescriptive path or Work Area Level 1 would likely be appropriate; if the work had been 2,600 ft² (52%), it would hit the Level 3 / larger alteration triggers.)
Related provisions (CEBC)
- § 301.1 — Applicability; the repair/alteration/change of occupancy/addition/relocation must comply with Sections 301.2, 301.3 or 301.4.
- § 301.4 — Relocated or moved buildings; relocated buildings must comply with CBC new‑building rules (separate path).
- Chapter 4 (Repairs) — Repairs are handled under Chapter 4 and are separate from the three compliance choices.
- Chapters 6–12 (Work Area method) — Classification of work and Level 1/2/3 technical requirements (use for most reconfigurations).
- Chapter 5 (Prescriptive) — Prescriptive compliance method requirements for certain alterations.
- Chapter 13 (Performance) — Performance compliance, numerical scoring and evaluation approach (note adoption caveats).
Code references
Grounded in the retrieved California Existing Building Code — click a citation to read the verbatim passage:
CBC § 301 High relevance — show source text
This code provides three main options for a designer in dealing with alterations of existing buildings. These are laid out in Section 301 of this code:
Option 1: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Prescriptive Compliance Method given in Chapter 5. It should be noted that this method originates from the former Chapter 34 of the IBC (2012 and earlier editions).
Option 2: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Work Area Compliance Method given in Chapters 6 through 12.
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Option 3: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Performance Compliance Method given in Chapter 13. It should be noted that this option was also provided in the former Chapter 34 of the IBC (2012 and earlier editions).
Under limited circumstances, a building alteration can be made to comply with the laws under which the building was originally built, as long as the accessibility requirements are met, there has been no substantial structural damage and there will be limited structural alteration. Flood hazard provisions also must still be addressed where there is a substantial improvement.
Note that all repairs must comply with Chapter 4 and all relocated buildings are addressed by Chapter 14.
ARRANGEMENT AND FORMAT OF THE 2025 CEBC
The format of the CEBC allows each chapter to be devoted to a particular subject. The following table shows how the CEBC is divided. The subsequent table shows CEBC requirements that are correlated with other California Codes. The chapter synopses detail the scope and intent of the provisions of the CEBC.
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.
CEBC § 3-3 High relevance — show source text
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members added as part of the alteration shall comply with the California Building Code . This exception shall not apply to the following:
Alterations for accessibility required by the California Building Code, Chapter 11A.
Alterations that constitute substantial improvement in flood hazard areas, which shall comply with Sections 503.2, 701.3 or 1303.1.3.
Structural provisions of Section 304, Chapter 5 or to the structural provisions of Sections 706, 805 and 906.
301.3.1 Prescriptive compliance. Alterations, additions and changes of occupancy complying with Chapter 5 of this code in buildings complying with the California Fire Code shall be considered in compliance with the provisions of this code.
Exception: Hospital buildings removed from acute care service, skilled nursing facilities, intermediate-care facilities, correctional treatment centers and acute psychiatric hospitals [OSHPD 1R, 2, 4 and 5]. The provisions of adopted sections in Chapters 3 through 5 shall control the alteration, repair and change of occupancy or function of existing structures for applications listed in Section 1.10.1, 1.10.2, 1.10.4 and 1.10.5 regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD). Refer to Chapter 3A for services, systems and utilities that serve OSHPD 1 buildings.
301.3.2 Work area compliance method. A lterations, additions and changes of occupancy complying with the applicable requirements of Chapters 6 through 12 of this code shall be considered in compliance with the provisions of this code.
301.3.3 Performance compliance method. Alterations, additions and changes of occupancy complying with Chapter 13 of this code shall be considered in compliance with the provisions of this code.
Note: [HCD 1 & HCD 2] The provisions contained in Chapter 13 are not adopted by HCD, but may be available for adoption by a local ordinance. (See Section 1.1.11.)
301.4 Relocated or moved buildings. Relocated or moved buildings shall comply with the requirements of Chapter 14.
SECTION 302—GENERAL PROVISIONS
302.1 Dangerous conditions. The code official shall have the authority to require the elimination of conditions deemed dangerous.
302.1.1 Dangerous conditions. [BSC] Regardless of the extent of structural or nonstructural damage, the code official shall have the authority to require the elimination of conditions deemed dangerous.
302.2 Additional codes. Alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and structures shall comply with the provisions for alterations, repairs, additions and changes of occupancy or relocation, respectively, in this code and the California Energy Code, California Fire Code, California Mechanical Code, California Plumbing Code, California Residential Code and California Electrical Code . Where provisions of the other codes conflict with provisions of this code, the provisions of this code shall take precedence.
CBC § 301 High relevance — show source text
The IEBC is a model code in the International Code family of codes intended to provide requirements for repair and alternative approaches for alterations, changes of occupancy and additions to existing buildings. A large number of existing buildings and structures do not comply with the current building code requirements for new construction. Although many of these buildings are potentially salvageable, rehabilitation is often cost-prohibitive because compliance with all the requirements for new construction could require extensive changes that go well beyond the value of the building or the original scope of the alteration. At the same time, it is necessary to regulate construction in existing buildings that undergo additions, alterations, extensive repairs or change of occupancy. Such activity represents an opportunity to ensure that new construction complies with the current building codes and that existing conditions are maintained, at a minimum, to their current level of compliance or are improved as required to meet basic safety levels. To accomplish this objective, and to make the alteration process easier, this code allows for options for controlled departure from full compliance with the International Codes dealing with new construction, while maintaining basic levels for fire safety, structural and life safety features of the rehabilitated building.
This code provides three main options for a designer in dealing with alterations of existing buildings. These are laid out in Section 301 of this code:
Option 1: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Prescriptive Compliance Method given in Chapter 5. It should be noted that this method originates from the former Chapter 34 of the IBC (2012 and earlier editions).
Option 2: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Work Area Compliance Method given in Chapters 6 through 12.
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Option 3: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Performance Compliance Method given in Chapter 13. It should be noted that this option was also provided in the former Chapter 34 of the IBC (2012 and earlier editions).
Under limited circumstances, a building alteration can be made to comply with the laws under which the building was originally built, as long as the accessibility requirements are met, there has been no substantial structural damage and there will be limited structural alteration. Flood hazard provisions also must still be addressed where there is a substantial improvement.
Note that all repairs must comply with Chapter 4 and all relocated buildings are addressed by Chapter 14.
ARRANGEMENT AND FORMAT OF THE 2025 CEBC
The format of the CEBC allows each chapter to be devoted to a particular subject. The following table shows how the CEBC is divided. The subsequent table shows CEBC requirements that are correlated with other California Codes. The chapter synopses detail the scope and intent of the provisions of the CEBC.
CEBC § 1.10.1 High relevance — show source text
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Chapter 3 Provisions for All Compliance Methods.
Chapter 3 guides the use of the three compliance methods of the CEBC and provides requirements that apply globally. The globally applicable requirement include general requirements related to buildings materials and other applicable codes, storm shelters, structural loads, in-situ load tests, accessibility, smoke alarms, carbon monoxide detection and exterior wall coverings.
Chapter 3A Provisions for All Compliance Methods.
Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 4 Repairs.
Chapter 4, a chapter independent of the three compliance methods, governs the repair of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.
Chapter 4A Repairs.
Chapter 4A governs the repair of existing buildings regulated by the Department of Health Care Access and Information/Office of State- wide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 5 Prescriptive Compliance Method.
Chapter 5 provides one of the three main options of compliance available in the CEBC for buildings and structures undergoing alteration, addition or change of occupancy. The base requirements are more administrative in nature. The structural triggers for upgrades are consistent with the Work Area Method.
Chapter 5A Prescriptive Compliance Method.
Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 6 Classification of Work.
Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.
Chapter 7 Alterations—Level 1.
Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.
Chapter 8 Alterations—Level 2.
A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.
Chapter 9 Alterations—Level 3.
CEBC § 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).
CEBC § 1.11. High relevance — show source text
The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.
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3 A PROVISIONS FOR ALL COMPLIANCE METHODS
User notes:
About this chapter: Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers [applications listed in Section 1.10.1 (OSHPD 1)].
SECTION 301 A —ADMINISTRATION
301 A .1 Applicability. The provisions of this chapter shall control the alteration, repair, addition and change of occupancy of existing structures for applications listed in Sections 1.10.1 [OSHPD 1] regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).
California Energy Commission, State Fire Marshal and DSA-AC requirements for existing structures shall be enforced by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).
301 A .1.1 Bleachers, grandstands and folding and telescopic seating. Existing bleachers, grandstands and folding and telescopic seating shall comply with ICC 300.
301 A .2 Repairs. Repairs shall comply with the requirements of Chapter 4 A .
301 A .3 Alteration, addition or change of occupancy. The alteration, addition or change of occupancy of all existing buildings or structures shall comply with one of the methods or categories listed in Section 301 A .3.1, 301 A .3.2 or 301 A .3.3. Section 304A.3.2 applies to all methods or categories. Sections 301 A .3.1 through 301 A .3.3 shall not be applied in combination with each other , except when permitted by the enforcement agency.
Exception: Subject to the approval of the enforcement agency, alterations complying with the laws in existence at the time the building or the affected portion of the building was built shall be considered in compliance with the provisions of this code. New structural members added as part of the alteration shall comply with the California Building Code .
301 A .3.1 Prescriptive compliance method. Alterations, additions and changes of occupancy complying with Chapter 5 A of this code for existing buildings or structures shall be considered in compliance with the provisions of this code.
CEBC § 1.10.1 High relevance — show source text
Chapter 5A Prescriptive Compliance Method.
Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 6 Classification of Work.
Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.
Chapter 7 Alterations—Level 1.
Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.
Chapter 8 Alterations—Level 2.
A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.
Chapter 9 Alterations—Level 3.
Chapter 9 provides the technical requirements for those existing buildings that undergo Level 3 alterations. Level 3 alterations are those involving alterations that cover 50 percent of the aggregate area of the building. Under certain situations, this chapter also intends to improve the safety of certain building features beyond the work area and in other parts of the building where no alteration work might be taking place.
Chapter 10 Change of Occupancy.
The purpose of Chapter 10 is to address existing buildings that are subject to a change of occupancy. This chapter is an assembly of requirements to upgrade safety without having to comply fully as a new building. A change of occupancy classification is considered a change of occupancy, however, it will involve a higher level of regulation since the use of the building has made a more significant change.
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Chapter 11 Additions.
Chapter 11 provides the requirements for additions, which are considered new construction. The requirements focus on safely integrating the addition with the existing building. This includes issues such as limiting the overall height and area of the building where the addition is not separated by a fire wall.
Chapter 12 Historic Buildings —Reserved
Chapter 12 is not adopted by the State of California. Historic buildings and structures shall comply with Part 8, Title 24, California Code of Regulations.
Chapter 13 Performance Compliance Methods.
Chapter 13 allows for existing buildings to be evaluated to show that alterations or a change of occupancy, while not meeting new construction requirements, will provide a level of safety to demonstrate compliance. Provisions are based on a numerical scoring system involving 21 safety parameters where, when evaluated, such buildings must meet a minimum overall safety score.
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 § 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.
CEBC § 1224.39 High relevance — show source text
These services require compliance with the_ current functional requirements for that service as defined in California Building Code, Section 1224.39, subject to the provisions of Section 506.1. d. New nonacute care services listed in Section 312.3.1, Item c shall be permitted provided they are in excess of the minimum services required for licensure and operation of the general acute care hospital. If patients are served by this service, it must meet the current functional requirements for that service as defined in California Building Code, Section 1224.39, subject to the provisions of Section 506.1.
312.3.3 SPC non-GACH buildings containing a change of licensed nursing services under existing license. A change of service or function for all, or a portion, of the SPC building removed from general acute care service requires compliance with the current functional requirements for that service as defined in California Building Code, Section 1224, subject to the provisions of Section 506.1.
312.3.3.1 Intermediate care and/or skilled nursing services. When general acute care services are removed from an SPC building which is intended to be used for separate and distinct intermediate care and/or skilled nursing services, and the new services will be licensed under the existing license of the general acute care hospital, these new services shall comply with current functional requirements as defined in California Building Code, Section 1224.38 and/or 1224.40, and Section 310A.1.1.1.5 of this code for a nonconforming hospital building.
312.3.3.2 Psychiatric nursing service. When general acute care services are removed from an SPC building which is intended to be used for separate and distinct psychiatric nursing services, and the new services will be licensed under the existing license of the general acute care hospital, these new services shall comply with current functional requirements for that service as defined in California Building Code, Section 1228, and Section 310A.1.1.1.5 of this code for a nonconforming hospital building.
312.3.4 SPC non-GACH buildings containing other occupancies and/or uses. Other occupancies and/or uses shall comply with the occupancy/use requirements of the California Building Standards Code for that occupancy or use. Subject to the approval of the building official, the use or occupancy of existing buildings is allowed to be occupied for purposes in other groups, or within the same group, provided the new or proposed use is less hazardous, based on life and fire risk, than the existing use.
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312.3.5 Vacant space. Spaces vacated through the removal of general acute care services that are intended to remain vacant must be in conformance with California Building Code, Section 116.1. The hospital shall submit a project to the Office to demonstrate remediation of potential unsafe and insanitary conditions.
312.3.6 Chemical dependency recovery services. Chemical dependency recovery services shall be permitted to be provided within a hospital building that has been removed from general acute care use.
SECTION 313 [SFM]—EXISTING GROUP R-1 AND GROUP R-2 OCCUPANCIES
CEBC § 309.2.1 Medium relevance — show source text
2||||X|X|||||||||||||||||||| |309.2.1|||X|||||||||||||||||||||| |310 – 311|||||||||||X|X|||X|||||||||| |312|||||||||||X|||||||||||||| |313 – 316|||X|||||||||||||||||||||| |317 – 322|X|||||||X|X|||||||||||||||| |323||||||||X|X||||||||||||||||
The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.
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User notes:
About this chapter: Chapter 3 explains the three compliance options for alterations and additions available in the code. In addition, this chapter also lays out the methods to be used for seismic design and evaluation throughout this code. Finally, this chapter clarifies that provisions in other I-Codes related to repairs, alterations, additions, relocation and changes of occupancy must also be addressed unless they conflict with this code. In that case, this code takes precedence.
SECTION 301—ADMINISTRATION
301.1 Applicability. The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with Section 301.2, 301.3 or 301.4. The provisions of Sections 302 through 309 shall apply to all alterations, repairs, additions, relocation of structures and changes of occupancy regardless of compliance method. [OSHPD 1R, 2, 4 and 5] Section 301.4 not permitted by OSHPD.
Exceptions: 1. Existing state-owned structures. [BSC] The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with the provisions of Sections 317 through 322 as the minimum standards for earthquake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University or the Judicial Council. The provisions of Sections 317 through 322 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings. 2. Public school buildings [DSA-SS] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as public school buildings under the jurisdiction of the Division of the State Architect—Structural Safety (DSA-SS, refer to Section 1.9.2.1) where required by Sections 4-307 and 4-309(c) of the California Administrative Code. The provisions of Sections 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public school buildings currently under the jurisdiction of DSA-SS. 3. _**Community college buildings.
CEBC § 422.3 Medium relevance — show source text
503 A .16 Reserved.
503 A .17 Ambulatory care facilities. Where a work area exceeds 50 percent of the building area and the work area includes an existing ambulatory care facility, the following shall be provided:
- A smoke compartment in accordance with Section 422.3 of the California Building Code where the alteration results in an ambulatory care facility greater than 10,000 square feet on one story.
- Separation from adjacent spaces in accordance with Section 422.2 of the California Building Code, where any such facility has the potential for four or more care recipients are to be incapable of self-preservation at any time.
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503 A .18 Reserved.
503 A .19 Reserved.
503 A .20 Two-way communications systems. Where the work area for alterations exceeds 50 percent of the building area and the building has elevator service, a two-way communication systems shall be provided where required by Section 1009.8 of the Califor- nia Building Code.
SECTION 504 A
RESERVED
SECTION 505 A
RESERVED
SECTION 506 A —CHANGE OF OCCUPANCY
506 A .1 Compliance. A change of occupancy shall not be made in any building unless that building is made to comply with the requirements of the California Building Code for the use or occupancy. Changes of occupancy in a building or portion thereof shall be such that the existing building is not less complying with the provisions of this code than the existing building or structure was prior to the change. Subject to the approval of the building official, changes of occupancy shall be permitted without complying with all of the requirements of this code for the new occupancy, provided that the new occupancy is less hazardous, based on life and fire risk, than the existing occupancy.
Exception: The building need not be made to comply with Chapter 16 A of the California Building Code unless required by Section 506 A .5.
506 A .1.1 Change in function . A change in function shall require compliance with all the functional requirements for new construc- tion in the California Building Code, including requirements in California Building Code Section 1224. Compliance shall be only as necessary to meet the specific provisions and is not intended to require the entire building be brought into compliance.
Exception: Minimum room clearances, areas and dimensions may meet the requirements of the 2001 California Building Code for existing rooms re-used for a similar purpose, subject to the approval of OSHPD.
506 A .2 Certificate of occupancy. A certificate of occupancy shall be issued where it has been determined that the requirements for the new occupancy classification have been met.
506 A .3 Stairways. An existing stairway shall not be required to comply with the requirements of Section 1011 of the California Build- ing Code where the existing space and construction does not allow a reduction in pitch or slope.
Frequently asked questions
Can I mix a Prescriptive and a Performance approach on the same project?
No — the code states the methods shall not be applied in combination unless the enforcement agency permits it. Always obtain the enforcement agency’s approval before combining methods.
If my work is only repairs, do I pick one of the three methods?
No — repairs are governed by Chapter 4, which is separate from the three compliance methods. Check Chapter 4 for repair limits and criteria.
My project is a hospital/OSHPD facility — does that change which method I can use?
Yes — hospitals and other OSHPD‑regulated facilities have special chapters (e.g., 3A, 5A) and adoption notes; some methods or sections may be adjusted or not adopted for those facilities. Consult the hospital‑specific chapters and the regulating agency.
What if my alteration covers exactly 50% of the building?
The 50% area is a key trigger used in Work Area definitions (Level 2 vs Level 3). Confirm the exact classification language in the Work Area chapters (Chapters 6–9) to determine whether the project is Level 2 or Level 3 in your circumstance.
Who decides which method I must use?
You (owner/designer) select the compliance method appropriate to the project, but the building official/enforcement agency enforces the code and may require a particular method or limit combinations. Always confirm with the enforcing agency early.
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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