CBC · California Building Code
Group designations & scope
This hub explains where the CBC defines occupancy groups, how to determine a building’s group(s), and which CBC chapters and sections govern special requirements.
Last reviewed: July 5, 2026
Overview
This hub covers how the California Building Code (CBC) classifies buildings and spaces by occupancy group and the scope that drives construction, means of egress, fire‑protection, and separation requirements. Chapter 3 establishes the scope and purpose of occupancy classification (see §301.1) and the formal occupancy rules that determine which group(s) apply to a building or portion thereof (§302.1) .
The CBC lists the named groups (A, B, C, E, F, H, I, L, M, R, S, U, etc.) and then gives the characteristics and limits for each group in Sections 303–312; those group descriptions are the starting point for selecting construction, fire‑protection, and egress provisions . Chapter 4 then contains special detailed requirements keyed to particular groups (for example, Group I and Group H conditions) that modify or add to the baseline rules in Chapter 3 .
Occupancy classification also interacts with other parts of the code and related California codes: mixed or multiple occupancies (see cross references such as Section 508), change‑of‑occupancy procedures in the California Existing Building Code (Chapter 10, Sections 1001–1003), and agency‑specific scope notes in Chapter 1 (OSHPD, DSA, etc.) .
In this section
Code references
Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:
CBC § 1.9.2.2.1 High relevance — show source text
1.9.2.2.1 Applicable administrative standards.
1. Title 24, Part 1, California Code of Regulations: 1.1. Sections 4-301 through 4-355, Group 1, and Sections 4-401 through 4-435, Group 2, Chapter 4. 2. Title 24, Part 2, California Code of Regulations: 2.1. Sections 1.1 and 1.9.2 of Chapter 1, Division I. 2.2. Sections 102.1, 102.2, 102.3, 102.4, 102.5, 104.2.3, 104.9, 104.10, 106.1, 107.2.5, 110.3.5 and 110.3.7 of Chapter 1, Division II.
1.9.2.2.2 Applicable building standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10, 11 and 12, Califor- nia Code of Regulations.
The Division of the State Architect-Structural Safety/Community Colleges [DSA-SS/CC] adopts the following building standards in Title 24, Part 2:
Chapters 2 through 10, 12, 14, 15, 16, 17A, 18A, 19, 20, 21, 22, 23, 24, 25, 26, 30, 31, 32, 33 and 35.
1.9.2.2.3 Identification of amendments. Division of the State Architect—Structural Safety/Community Colleges amendments in this code appear preceded with the acronym [DSA-SS/CC].
Exception: Chapters 17A, and 18A—Amendments appearing in these chapters without an acronym have been co-adopted by DSA-SS, DSA-SS/CC and OSHPD.
1.9.2.2.4 Reference to other chapters. Where reference is made within the California Building Standards Code (CBSC) to sections in Chapters 17 and 18, the respective sections in Chapters 17A and 18A shall apply instead.
SECTION 1.10—DEPARTMENT OF HEALTH CARE ACCESS AND
INFORMATION/OFFICE OF STATEWIDE HOSPITAL PLANNING AND DEVELOPMENT
1.10.1 OSHPD 1 and OSHPD 1R. Specific scope of application of the agency responsible for enforcement, enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.
Application— [OSHPD 1] General acute care hospital buildings. [OSHPD 1R] Nonconforming hospital SPC or freestanding buildings that have been removed from acute-care service.
Enforcing agency— Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD). The office shall enforce the California Energy Commission—Energy Regulations, the Division of the State Architect—Access Compliance regula- tions and the regulations of the Office of the State Fire Marshal for the above stated facility types.
CBC § 1.9.2.1.4 Medium relevance — show source text
Exception: Chapters 16A, 17A, 18A, 19A, 21A and 22A—Amendments appearing in these chapters without an acronym have been co-adopted by DSA-SS and OSHPD.
1.9.2.1.4 Reference to other chapters. Where reference is made within the California Building Standards Code (CBSC) to sections in Chapters 16, 17, 18, 19, 21 and 22, the respective sections in Chapters 16A, 17A, 18A, 19A, 21A and 22A shall apply instead.
1.9.2.2 DSA-SS/CC Division of the State Architect- Structural Safety/Community Colleges
Application— Community Colleges. The Division of the State Architect has been delegated the authority by the Department of General Services to promulgate alternate building standards for application to community colleges, which a community college may elect to use in lieu of standards promulgated by DSA-SS in accordance with Section 1.9.2.1.
Enforcing agency— Division of the State Architect- Structural Safety/Community Colleges (DSA-SS/CC)
The Division of the State Architect has been delegated the authority by the Department of General Services to review and approve the design and oversee construction of community colleges electing to use the alternative building standards as provided in this section.
Authority cited— Education Code Section 81053.
Reference— Education Code Sections 81052, 81053 and 81130 through 81147.
1.9.2.2.1 Applicable administrative standards.
1. Title 24, Part 1, California Code of Regulations: 1.1. Sections 4-301 through 4-355, Group 1, and Sections 4-401 through 4-435, Group 2, Chapter 4. 2. Title 24, Part 2, California Code of Regulations: 2.1. Sections 1.1 and 1.9.2 of Chapter 1, Division I. 2.2. Sections 102.1, 102.2, 102.3, 102.4, 102.5, 104.2.3, 104.9, 104.10, 106.1, 107.2.5, 110.3.5 and 110.3.7 of Chapter 1, Division II.
1.9.2.2.2 Applicable building standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10, 11 and 12, Califor- nia Code of Regulations.
The Division of the State Architect-Structural Safety/Community Colleges [DSA-SS/CC] adopts the following building standards in Title 24, Part 2:
Chapters 2 through 10, 12, 14, 15, 16, 17A, 18A, 19, 20, 21, 22, 23, 24, 25, 26, 30, 31, 32, 33 and 35.
CBC § 902.1 Medium relevance — show source text
2 Exception||||†|†|||||||||||||||||||| |902.1_Reserved_|||X|||||||||||||||||||||| |902.2 – 902.2.1|||X|||||||||||||||||||||| |902.2 – 902.3||||†|†|||||||||||||||||||| |903.4||||†|†|||||||||||||||||||| |904.1|||X|||||||||||||||||||||| |904.2|||X|||||||||||||||||||||| |904.2.1|||X|||||||||||||||||||||| |908||||†|†||||||||||||||||||||
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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9 ALTERATIONS—LEVEL 3
User notes:
About this chapter : Chapter 9 provides the technical requirements for those existing buildings that undergo Level 3 alterations. The purpose of this chapter is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, building spaces and building structural system. This chapter is distinguished from Chapters 7 and 8 by involving alterations that cover 50 percent or more of the aggregate area of the building. In contrast, Level 1 alterations do not involve space reconfiguration, and Level 2 alterations involve extensive space reconfiguration that does not exceed 50 percent of the building area. Depending on the nature of alteration work, its location within the building, and whether it encompasses one or more tenants, improvements and upgrades could be required for the open floor penetrations, sprinkler system or the installation of additional means of egress such as stairs or fire escapes. At times and under certain situations, this chapter also is intended 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.
SECTION 901—GENERAL
901.1 Scope. Level 3 alterations as described in Section 604 shall comply with the requirements of this chapter.
901.2 Compliance. In addition to the provisions of this chapter, work shall comply with all of the requirements of Chapters 7 and 8. The requirements of Sections 802, 803, 804 and 805 shall apply within all work areas whether or not they include exits and corridors shared by more than one tenant and regardless of the occupant load.
Exception: Buildings in which the reconfiguration of space affecting exits or shared egress access is exclusively the result of compliance with the accessibility requirements of Section 306.7.1 shall not be required to comply with this chapter.
SECTION 902—SPECIAL USE AND OCCUPANCY
902.1 Reserved.
902.2 Group R-2.1 occupancies. Group R-2.1 occupancies shall be classified in accordance with Section 308.2 of the California Build- ing Code .
CBC § 310.2 Medium relevance — show source text
1|||X|||||||||||||||||||||| |310.2|||X|X||||||||||||||||||||| |310.3|||X|X||||||||||||||||||||| |310.3.1|||X|||||||||||||||||||||| |310.3.2|||X|||||||||||||||||||||| |310.4|||X|X||||||||||||||||||||| |310.4.1|||X|||||||||||||||||||||| |310.4.2|||X|X|X|||||||||||||||||||| |310.5|||X|||||||||||||||||||||| |310.6|||X|||||||||||||||||||||| |313|||X|||||||||||||||||||||| |314|||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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OCCUPANCY CLASSIFICATION AND USE
User notes:
About this chapter: Chapter 3 provides the criteria by which buildings and structures are classified into use groups and occupancies. Through the balance of the code, occupancy classification is fundamental in the setting of features of construction; occupant safety requirements, especially building limitations; means of egress; fire protection systems; and interior finishes.
ICC code development note: Code change proposals to sections preceded by the designation [F] will be considered by the IFC code development committee meeting during the 2024 (Group A) Code Development Cycle. All other code change proposals will be considered by a code development committee meeting during the 2025 (Group B) Code Development Cycle.
SECTION 301—SCOPE
301.1 General. The provisions of this chapter shall control the classification of all buildings and structures as to occupancy and use. Different classifications of occupancy and use represent varying levels of hazard and risk to building occupants and adjacent properties.
SECTION 302—OCCUPANCY CLASSIFICATION AND USE DESIGNATION
302.1 Occupancy classification. Occupancy classification is the formal designation of the primary purpose of the building, structure or portion thereof. Structures shall be classified into one or more of the occupancy groups specified in this section based on the nature of the hazards and risks to building occupants generally associated with the intended purpose of the building or structure. An area, room or space that is intended to be occupied at different times for different purposes shall comply with all applicable requirements associated with such potential multipurpose. Structures containing multiple occupancy groups shall comply with Section 508. Where a structure is proposed for a purpose that is not specified in this section, such structure shall be classified in the occupancy it most nearly resembles based on the fire safety and relative hazard. Occupiable roofs shall be classified in the group that the occupancy most nearly resembles, according to the fire safety and relative hazard, and shall comply with Section 503.1.4.
- Assembly (see Section 303): Groups A-1, A-2, A-3, A-4 and A-5.
- Business (see Section 304): Group B.
CBC § 2.1 Medium relevance — show source text
- Business (see Section 304): Group B. 3. [SFM] Organized Camps (see Section 450): Group C. 4. Educational (see Section 305): Group E. 5. Factory and Industrial (see Section 306): Groups F-1 and F-2. 6. High Hazard (see Section 307): Groups H-1, H-2, H-3, H-4 and H-5. 7. Institutional (see Section 308): Groups I-2, I-3 and I-4. 8. [SFM] Laboratory (see Section 202): Group B, unless classified as Group L (see Section 453) or Group H (see Section 307). 9. [SFM] Laboratory Suites (see Section 453): Group L. 10. Mercantile (see Section 309): Group M. 11 . Residential (see Section 310): Groups R-1, R-2, R-2.1, R-3, R-3.1 and R-4. 12 . Storage (see Section 311): Groups S-1 and S-2. 13 . Utility and Miscellaneous (see Section 312): Group U. 14. [SFM] Existing buildings housing existing protective social care homes or facilities established prior to 1972 (see California Fire Code Chapter 11 and California Existing Building Code).
302.1.1 Reserved
302.1.2 Reserved
302.1.3 Pharmacies; veterinary facilities; barbering, cosmetology or electrolysis establishments; and acupuncture offices. See Chapter 12.
302.2 Use designation. Occupancy groups contain subordinate uses having similar hazards and risks to building occupants. Uses include, but are not limited to, those functional designations specified within the occupancy group descriptions in Section 302.1. Certain uses require specific limitations and controls in accordance with the provisions of Chapter 4 and elsewhere in this code.
SECTION 303—ASSEMBLY GROUP A
303.1 Assembly Group A. Assembly Group A occupancy includes, among others, the use of a building or structure, or a portion thereof, for the gathering of persons for purposes such as civic, social or religious functions; recreation, food or drink consumption or awaiting transportation ; motion picture and television production studio sound stages, approved production facilities and production locations; or for the showing of motion pictures when an admission fee is charged and when such building or structure is open to the public and has a capacity of 10 or more persons.
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OCCUPANCY CLASSIFICATION AND USE
303.1.1 Small buildings and tenant spaces. A building or tenant space used for assembly purposes with an occupant load of less than 50 persons shall be classified as a Group B occupancy.
CBC § 406.3.2 Medium relevance — show source text
See Section 420.
b. The required separation from areas used only for private or pleasure vehicles shall be reduced by 1 hour but not to less than 1 hour.
c. See Sections 406.3.2 and 406.6.4.
d. Separation is not required between occupancies of the same classification.
e. See Section 422.2 for ambulatory care facilities.
f. Occupancy separations that serve to define fire area limits established in Chapter 9 for requiring fire protection systems shall also comply with Section 707.3.10 and Table
707.3.10 in accordance with Section 901.7.
g._ [SFM]_Group I and F1 occupancies and Group R-2.1 and F-1 occupancies shall have a 3 hour separation.
h._ [SFM]_Commercial kitchens not associated with cafeterias and similar dining facilities in Group I-2 and Group R-2.1 shall have a 2-hour separation and shall be protected by an
automatic sprinkler system.
i._ [SFM]__ Group E child-care separation with I-4 child care can be reduced to 1 hour with the installation of automatic fire sprinklers in accordance with Section 903.3.1.1.
j. When not considered an accessory use in accordance with Section 508.2.4, the required separation between Group I-2 and required covers for accessible entrances and emergency_
vehicle entrances, when in accordance with Section 406.5.2 and protected by an automatic sprinkler system, shall be reduced by 1 hour but not to less than 1 hour. See Section
903.2.21.|S = Buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1.
NS = Buildings not equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1.
N = No separation requirement.
NP = Not Permitted.
a. See Section 420.
b. The required separation from areas used only for private or pleasure vehicles shall be reduced by 1 hour but not to less than 1 hour.
c. See Sections 406.3.2 and 406.6.4.
d. Separation is not required between occupancies of the same classification.
e. See Section 422.2 for ambulatory care facilities.
f. Occupancy separations that serve to define fire area limits established in Chapter 9 for requiring fire protection systems shall also comply with Section 707.3.10 and Table
707.3.10 in accordance with Section 901.7.
g._ [SFM]_Group I and F1 occupancies and Group R-2.1 and F-1 occupancies shall have a 3 hour separation.
h._ [SFM]_Commercial kitchens not associated with cafeterias and similar dining facilities in Group I-2 and Group R-2.1 shall have a 2-hour separation and shall be protected by an
automatic sprinkler system.
i._ [SFM]__ Group E child-care separation with I-4 child care can be reduced to 1 hour with the installation of automatic fire sprinklers in accordance with Section 903.3.1.1.
j. When not considered an accessory use in accordance with Section 508.2.4,CBC § 3-5 Medium relevance — show source text
304 Business Group B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
305 Educational Group E . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
306 Factory Group F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
307 High-Hazard Group H . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
308 Institutional Group I . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
309 Mercantile Group M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
310 Residential Group R. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
311 Storage Group S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
312 Utility and Miscellaneous Group U . . . . . . . . . . . . . . 3-18
313 Laboratories Group L [SFM]. . . . . . . . . . . . . . . . . . . . . . .3-19
314 Organized Camps Group C [SFM]. . . . . . . . . . . . . . . . . .3-19
CHAPTER 4 SPECIAL DETAILED REQUIREMENTS
BASED ON OCCUPANCY AND USE . . . . . . . . . . . . . . . . . . . .4-1
401 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
402 Covered Mall and Open Mall Buildings . . . . . . . . . . . . 4-5
403 High-Rise Buildings and Group I-2 Occupancies Having Occupied Floors Located More Than 75 Feet above the Lowest Level of
Fire Department Vehicle Access . . . . . . . . . . . . . . . 4-9
404 Atriums. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12
405 Underground Buildings . . . . . . . . . . . . . . . . . . . . . . . . 4-13
406 Motor-Vehicle-Related Occupancies. . . . . . . . . . . . . 4-15
407 Group I-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-19
408 Group I-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-24
CBC § 1.10.4.3 Medium relevance — show source text
1.10.4.3 Identification of amendments. For applications listed in Section 1.10.4, amendments appear in this code preceded with the acronym [OSHPD 4], unless the entire chapter is applicable.
1.10.4.4 Reference to other chapters. Where reference is made within this code to sections in Chapters 16, 17, 18, 19, 21 and 22, the respective sections in Chapters 16A, 17A, 18A, 19A, 21A and 22A shall apply instead.
Authority— Health and Safety Code Sections 127010, 127015 and 129790.
References— Health and Safety Code Sections 127010, 127015, 1275 and 129675 through 130070.
1.10.5 OSHPD 5. Specific scope of application of the agency responsible for enforcement, enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.
Application— Acute psychiatric hospital buildings.
Enforcing agency— Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD). The office shall also enforce the California Energy Commission—Energy Regulations, the Division of the State Architect—Access Compliance regulations and the regulations of the Office of the State Fire Marshal for the above-stated facility type.
1.10.5.1 Applicable administrative standards. 1. Title 24, Part 1, California Code of Regulations: Chapter 7. 2. Title 24, Part 2, California Code of Regulations: Sections 1.1 and 1.10, Chapter 1, Division I, and as adopted in Chapter I, Division II.
1.10.5.2 Applicable building standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10 and 11.
The provision of Title 24, Part 2, as adopted and amended by OSHPD, shall apply to the applications listed in Section 1.10.5.
OSHPD 5 adopts the following building standards in Title 24, Part 2:
Chapters 2 through 10, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 30, 31, 32, 33 and 35.
1.10.5.3 Identification of amendments. For applications listed in Section 1.10.5, amendments appear in this code preceded with the acronym [OSHPD 5].
Authority— Health and Safety Code Sections 127010, 127015, 1275 and 129850.
References— Health and Safety Code Sections 127010, 127015, 129680, 1275 and 129675 through 130070.
1.10.6 OSHPD 6. Specific scope of application of the agency responsible for enforcement, enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.
Application —Chemical dependency recovery hospital not within an acute care hospital building or an acute psychiatric facility.
Enforcing agency —Local building department.
CBC § 1-33 Medium relevance — show source text
112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
113 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
114 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
115 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
CHAPTER 3 OCCUPANCY CLASSIFICATION AND USE . . . . .3-1
301 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
302 Occupancy Classification and Use Designation . . . . 3-3
303 Assembly Group A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
304 Business Group B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
305 Educational Group E . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
306 Factory Group F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
307 High-Hazard Group H . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
308 Institutional Group I . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
309 Mercantile Group M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
310 Residential Group R. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
311 Storage Group S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
312 Utility and Miscellaneous Group U . . . . . . . . . . . . . . 3-18
313 Laboratories Group L [SFM]. . . . . . . . . . . . . . . . . . . . . . .3-19
CBC § 1-24 Medium relevance — show source text
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-24
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-24
104 Duties and Powers of Building Official. . . . . . . . . . . 1-25
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
106 Floor and Roof Design Loads . . . . . . . . . . . . . . . . . . . 1-29
107 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-29
108 Temporary Structures, Equipment and Systems . . . . . . . . . . . . . . . . . . . . . 1-31
109 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
110 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
111 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-33
112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
113 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
114 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
115 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
CHAPTER 3 OCCUPANCY CLASSIFICATION AND USE . . . . .3-1
301 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
302 Occupancy Classification and Use Designation . . . . 3-3
CBC § 1001.1 Medium relevance — show source text
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10 CHANGE OF OCCUPANCY
User notes:
About this chapter : The purpose of this chapter is to provide regulations for the circumstances where an existing building is subject to a change of occupancy or a change of occupancy classification. A change of occupancy is not to be confused with a change of occupancy classification. The California Building Code defines different occupancy classifications in Chapter 3 and special occupancy requirements in Chapter 4. Within specific occupancy classifications there can be many different types of actual activities that can take place. For instance, a Group A-3 occupancy classification deals with a wide variation of different types of activities, including bowling alleys and courtrooms, indoor tennis courts and dance halls. When a facility changes use from, for example, a bowling alley to a dance hall, the occupancy classification remains A-3, but the different uses could lead to drastically different code requirements. Therefore, this chapter deals with the special circumstances that are associated with a change in the use of a building within the same occupancy classification as well as a change of occupancy classification.
SECTION 1001—GENERAL
1001.1 Scope. The provisions of this chapter shalle a change of occupancy occurs, as defined in Section 202.
1001.2 Certificate of occupancy. A change of occupancy or a change of occupancy within a space where there is a different fire protection system threshold requirement in Chapter 9 of th apply where current California Building Code than exists in the current building or space shall not be made to any structure without the approval of the code official. A certificate of occupancy shall be issued where it has been determined that the requirements for the change of occupancy have been met.
1001.2.1 Change of use. Any work undertaken in connection with a change in use shall conform to the applicable requirements for the work as classified in Chapter 6 and to the requirements of Sections 1002 through 1010.
1001.2.2 Change of occupancy classification. Where a building undergoes a change of occupancy classification, the provisions of Sections 1002 through 1011 shall apply.
1001.2.2.1 Partial change of occupancy. Where a portion of an existing building undergoes a change of occupancy classification, Section 1011 shall apply.
1001.3 Certificate of occupancy required. A certificate of occupancy shall be issued where a change of occupancy occurs that results in a different occupancy classification as determined by the California Building Code .
SECTION 1002—SPECIAL USE AND OCCUPANCY
1002.1 Compliance with the building code. Where an existing building or part of an existing building undergoes a change of occupancy to one of the special use or occupancy categories as described in Chapter 4 in the California Building Code, the building shall comply with all of the requirements of Chapter 4 of the California Building Code applicable to the special use or occupancy.
1002.2 Incidental uses. Where a portion of a building undergoes a change of occupancy to one of the incidental uses listed in Table 509.1 of the California Building Code, the incidental use shall comply with Section 509 of the California Building Code applicable to the incidental use.
SECTION 1003—BUILDING ELEMENTS AND MATERIALS
1003.1 General. Building elements and materials in portions of buildings undergoing a change of occupancy classification shall comply with Section 1011.
SECTION 1004—FIRE PROTECTION
CBC § 1002.2 Medium relevance — show source text
Evacuation plans 1002.2 Existing buildings 3310 Exit (see Exit) 1022, 1027 Exit access (see Exit Access) 1016, 1021 Exit discharge (see Exit Discharge) 1028 Exit enclosures 1023.2
Exit passageway 1024 Exit signs 1013, 2702.2 Fire escapes 412.7.3 Fire safety plans 1002.2 Floor surface 804, 1003.4 Gates 1010.4
Group I-2 407.2, 407.3, 407.4, 1019.4 Group I-3 408.2, 408.3, 408.4, 408.6, 408.8, 1019.4 Guards 1015
Handrails 1014
Hazardous materials 414.6.1.2, 415.11.2, 415.11.6.6 Headroom 1003.2, 1003.3 Heliports, Helistops 412.7.3 High-hazard Group H 415.11.2 High-rise 403.5, 403.6 Illumination 1008, 2702.2 Interior finish 803.13, 804 Ladders (see Ladders) Live loads Table 1607.1
Live/work units 508.5.3 Mezzanines 505.2.2, 505.2.3, 1004.2.2,
1009.1 Moving walk 1003.7 Number 1001.2, 1006 Occupant load 1004 Parking 406.5.7 Protruding objects 1003.3, 1005.7 Ramps 1012, 1019, 1027 Scoping 101.3, 108.2, 1001.1 Seating, fixed 1009.1, 1030 Special amusement areas 411.4 Stages 410.2.3, 410.5 Stairways 403.5, 404.6, 1005.3.1, 1011, 1019, 1023, 1027 Temporary structures 3103.4 Travel distance (see Travel Distance) 1006.2.1,
1017
Turnstile 1010.5
Underground buildings 405.5.1, 405.7 Width 1005.1, 1005.2, 1005.4, 1011.2, 1012.5.1, 1020.3, 1030.6, 1030.8 Mechanical (see Air Conditioning, Heating, Refrigeration and Ventilation) 101.4.2 Access 1011.12, 1208.4 Air transfer openings 705.11, 706.11, 707.10, 708.9, 709.8, 712.1.6, 713.10, 714.1.1, 717 Chimneys (see Chimneys) Code Chapter 28 Disconnected 3303.6
Frequently asked questions
How do I decide which occupancy group applies to my building or space?
You classify the building by its primary purpose and the hazards associated with that use, per §302.1; if a use isn’t listed, classify it as the occupancy it most nearly resembles. For multi‑purpose spaces the code requires applying all applicable requirements for the potential uses and, where necessary, following rules for mixed occupancies (see §302.1 and cross references to mixed‑occupancy provisions) .
What if a building contains more than one occupancy group?
The CBC provides rules for mixed and separated occupancies (see references in Chapter 3 and Section 508) and also prescribes required separations, fire‑protection, and construction types between groups where applicable; Chapter 4 contains additional special‑use requirements for specific groups that can affect separation and protection needs .
What happens when the use or occupancy of an existing building changes?
The California Existing Building Code addresses changes of occupancy: Chapter 10 (Sections 1001–1003) requires that a change of occupancy meet applicable requirements and that a code official approve the change before a new certificate of occupancy is issued; special use occupancies must also meet Chapter 4 requirements in the CBC .
More in California Building Code
- Administration & Permits
- Energy Efficiency
- Existing Buildings
- Occupancy Classification & Use
- Hazardous Materials & Occupancies
- Types of Construction
- Fire-Resistance & Fire Safety
- Interior Finishes
- Means of Egress
- Accessibility
- Exterior Walls
- Roofing & Roof Assemblies
- Structural Design
- Special Inspections & Tests
- Foundations & Soils
- Concrete
- Masonry
- Steel
- Wood
- Elevators & Conveying Systems
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