CBC · California Building Code

Assembly Group A — classification, small-assembly exceptions

In plain terms: the CBC calls most public gathering spaces "Group A," but if the entire tenant space or building used for assembly has fewer than 50 people it is classified as Group B (not Group A) per § 303.1.1; small accessory assembly rooms under 50 occupants or under 750 sq ft can also be treated as part of the host occupancy rather than a separate Group A space per § 303.1.2. Always document your occupant‑load calculation and confirm classification with the local building official because classification changes many design and safety requirements .

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Last reviewed: July 5, 2026

What the code requires

Assembly Group A is the occupancy category for spaces used for gathering people for civic, social, religious, recreational, food/drink, transportation waiting, certain motion‑picture/television production with audiences, and for showing motion pictures when open to the public and the space has a capacity of 10 or more persons — see § 303.1 . However, the code directs that a whole building or tenant space used for assembly with an occupant load of less than 50 persons be classified as Group B instead of Group A — see § 303.1.1 .

Requirements in detail

Which uses are Group A (summary)

  • General Group A definition: gathering of persons for civic, social, religious, recreation, food/drink, awaiting transportation, motion picture/television production sound stages with audiences, and showing motion pictures (when open to public and capacity ≥ 10) — § 303.1 .
  • Subclassifications A-1 through A-5 (types of assembly) are defined in following subsections (see § 303.2–303.6) and affect other requirements (e.g., sprinkler thresholds) — see § 303.2 et seq. .

Small‑assembly thresholds that change classification

The code uses simple numeric thresholds (occupant load and area) to treat small assembly spaces as non‑Assembly occupancies in certain circumstances:

Decision factor Rule / threshold Practical effect Code Reference
Motion picture screening capacity 10 or more persons to qualify as Group A when open to public A tiny screening room with capacity <10 is not treated as Group A under the motion‑picture clause of § 303.1 § 303.1
Whole building or tenant space occupant load Less than 50 persons → classify as Group B Entire tenant spaces/buildings with occupant load <50 are Group B (not Group A) per § 303.1.1 § 303.1.1
Accessory room occupant load Less than 50 persons and accessory to another occupancy → classify as Group B or part of that occupancy Small accessory assembly rooms inside other occupancy types are not separate Group A occupancies (e.g., a small lounge inside an office) § 303.1.2(1)
Accessory room area Less than 750 sq ft (70 m2) and accessory to another occupancy → classify as Group B or part of that occupancy Small accessory assembly rooms below the area threshold are not separate Group A occupancies § 303.1.2(2)

Notes:

  • The 50‑person threshold in § 303.1.1 applies to a "building or tenant space used for assembly purposes" — it is a classification rule for the whole tenant space or building, not just a single room unless that room is the tenant space. See § 303.1.1 .
  • The accessory thresholds in § 303.1.2 apply when the assembly space is accessory to another primary occupancy; they allow the accessory space to be treated as part of the host occupancy rather than as a separate Group A occupancy .

Interaction with other occupancy rules and protections

  • Small assembly exclusions affect how Chapters 5, 9 and 10 apply (height/area, sprinkler, and means‑of‑egress rules are occupancy‑dependent). For example, sprinkler requirements for Group A subgroups are set in Chapter 9; whether a space is treated as Group A or Group B will change which sprinkler thresholds apply (see § 903.2.1 and the Group A subparagraphs) .

Exceptions & special cases

  • Accessory to educational (Group E): a room or space used for assembly that is associated with a Group E occupancy is not considered a separate occupancy (see § 303.1.3) .
  • Religious facilities: accessory religious educational rooms and religious auditoriums with occupant loads of less than 100 per room or space are not considered separate occupancies (see § 303.1.4) — this is a higher threshold (100) that applies specifically to accessory religious rooms and auditoriums .
  • Special amusement areas (e.g., attractions) are governed by separate Chapter 4 provisions and must comply with Section 411 rather than be treated only by the Group A general rule (see § 303.1.5) .

If your situation sits on the boundary of these numeric thresholds (for example, tenant space occupant load computed at 48–52 persons), treat the determination as code‑critical: document the occupant load calculation and confirm classification with the authority having jurisdiction, because classification affects many downstream requirements (sprinklers, exits, fire ratings).

Common mistakes

  • Treating every gathering room as Group A without checking the 50‑person or accessory thresholds. § 303.1.1 and § 303.1.2 allow many small rooms/tenant spaces to be Group B .
  • Confusing the 10‑person motion‑picture threshold with the 50‑person general threshold. The motion‑picture clause in § 303.1 uses 10 persons for when showing motion pictures counts as Group A; the general small‑building rule for classification uses 50 persons in § 303.1.1 .
  • Ignoring the accessory vs. tenant‑space distinction: § 303.1.2 applies only when the room is accessory to another occupancy; a stand‑alone tenant space is evaluated under § 303.1.1 .
  • Overlooking the special religious provision: accessory religious educational rooms and auditoriums have a 100‑person threshold (§ 303.1.4), not 50 — that higher threshold is specific to religious uses .
  • Failing to document occupant‑load calculations used to make the classification — occupant load is the basis of several thresholds; keep the calculation (and code section used) in the project file (see occupant load rules referenced by § 303 and related tables).

Worked example

Scenario: A tenant improvement proposes a new café in a retail center. The design capacity (based on seating and standing areas and the occupant‑load calculation) is 45 persons.

Step 1 — Is the tenant space a whole building/tenant‑space assembly? Yes — the café is a tenant space used for assembly (food/drink consumption).

Step 2 — Apply § 303.1.1: because the tenant space occupant load is less than 50, the space is classified as Group B (not Group A) — see § 303.1.1 .

Practical consequences:

  • The café will be regulated as Group B for height/area, means‑of‑egress, and some fire protection thresholds unless another code provision or function (e.g., a cooking hood requiring additional sprinklers) imposes specific requirements.
  • If the café later adds seating or standing room that raises the occupant load to 50 or more, it would then be classified as Group A and the designer must reassess sprinkler and egress requirements per Group A provisions (see also Chapter 9 sprinkler thresholds for Group A subgroups) .

If instead the café had an accessory lounge inside an office tenant and that lounge were <750 sq ft or <50 persons, treat it under § 303.1.2 as part of the office occupancy (Group B) rather than a separate Group A space .

Related provisions

  • § 303.1.2 — Small assembly spaces; accessory room area and occupant‑load thresholds
  • § 303.1.3 — Assembly spaces associated with Group E (education) are not separate occupancies
  • § 303.1.4 — Accessory religious educational rooms and auditoriums (<100) are not separate occupancies
  • § 303.2 — Definitions of Assembly Group A‑1 (and see §§ 303.3–303.6 for A‑2 through A‑5)
  • § 903.2.1 (Chapter 9) — Automatic sprinkler thresholds for Group A subgroups; classification affects sprinkler requirements
  • § 1004 — Occupant load calculation (used to determine the numeric thresholds above) — see code cross‑references to occupant load rules in Chapter 10 and Chapter 3 references in the files

Code references

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

  • CBC § 303.1.2 High relevance — show source text

    303.1.2 Small assembly spaces. The following rooms and spaces shall not be classified as Assembly occupancies:

    1. A room or space used for assembly purposes with an occupant load of less than 50 persons and accessory to another occupancy shall be classified as a Group B occupancy or as part of that occupancy.
    2. A room or space used for assembly purposes that is less than 750 square feet (70 m [2] ) in area and accessory to another occupancy shall be classified as a Group B occupancy or as part of that occupancy.

    303.1.3 Associated with Group E occupancies. A room or space used for assembly purposes that is associated with a Group E occupancy is not considered a separate occupancy.

    303.1.4 Accessory to places of religious worship. Accessory religious educational rooms and religious auditoriums with occupant loads of less than 100 per room or space are not considered separate occupancies.

    303.1.5 Special amusement areas. Special amusement areas shall comply with Section 411.

    303.2 Assembly Group A-1. Group A-1 occupancy includes assembly uses, usually with fixed seating, intended for the production and viewing of the performing arts or motion pictures, including but not limited to:

    Motion picture and television production studio sound stages, approved production facilities and production locations. (with live audiences).

    Motion picture theaters

    Symphony and concert halls

    Television and radio studios admitting an audience

    Theaters

    303.3 Assembly Group A-2. Group A-2 occupancy includes assembly uses intended for food and/or drink consumption, including but not limited to:

    Banquet halls

    Casinos (gaming areas)

    Nightclubs

    Restaurants, cafeterias and similar dining facilities (including associated commercial kitchens)

    Taverns and bars

    303.4 Assembly Group A-3. Group A-3 occupancy includes assembly uses intended for worship, recreation or amusement and other assembly uses not classified elsewhere in Group A, including but not limited to:

    Amusement arcades

    Art galleries

    Bowling alleys

    Community halls

    Courtrooms

    Dance halls (not including food or drink consumption)

    Exhibition halls

    Funeral parlors

    Greenhouses for the conservation and exhibition of plants that provide public access

    Gymnasiums (without spectator seating)

    Indoor swimming pools (without spectator seating)

    Indoor tennis courts (without spectator seating)

    Lecture halls

    Libraries

    Museums

    Places of religious worship

    Pool and billiard parlors

    Waiting areas in transportation terminals

    303.5 Assembly Group A-4. Group A-4 occupancy includes assembly uses intended for viewing of indoor sporting events and activities with spectator seating, including but not limited to:

    Arenas

    Skating rinks

    Swimming pools

    Tennis courts

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    OCCUPANCY CLASSIFICATION AND USE

    303.6 Assembly Group A-5. Group A-5 occupancy includes assembly uses intended for participation in or viewing outdoor activities, including but not limited to:

    Amusement park structures

    Bleachers

    Grandstands

    Stadiums

    303.7 Fixed guideway transit systems. [SFM] Fixed guideway transit system buildings shall conform to the requirements of this code for their occupancy classification in addition to the provisions set forth in Section 443.

    303.8 Subterranean spaces for winery facilities in natural or manmade caves. [SFM] For fire and life safety requirements, see Section 446.

  • CBC § 302.1.1 High relevance — show source text

    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.

    303.1.2 Small assembly spaces. The following rooms and spaces shall not be classified as Assembly occupancies:

    1. A room or space used for assembly purposes with an occupant load of less than 50 persons and accessory to another occupancy shall be classified as a Group B occupancy or as part of that occupancy.
    2. A room or space used for assembly purposes that is less than 750 square feet (70 m [2] ) in area and accessory to another occupancy shall be classified as a Group B occupancy or as part of that occupancy.

    303.1.3 Associated with Group E occupancies. A room or space used for assembly purposes that is associated with a Group E occupancy is not considered a separate occupancy.

    303.1.4 Accessory to places of religious worship. Accessory religious educational rooms and religious auditoriums with occupant loads of less than 100 per room or space are not considered separate occupancies.

    303.1.5 Special amusement areas. Special amusement areas shall comply with Section 411.

    303.2 Assembly Group A-1. Group A-1 occupancy includes assembly uses, usually with fixed seating, intended for the production and viewing of the performing arts or motion pictures, including but not limited to:

    Motion picture and television production studio sound stages, approved production facilities and production locations. (with live audiences).

    Motion picture theaters

    Symphony and concert halls

    Television and radio studios admitting an audience

    Theaters

    303.3 Assembly Group A-2. Group A-2 occupancy includes assembly uses intended for food and/or drink consumption, including but not limited to:

    Banquet halls

    Casinos (gaming areas)

    Nightclubs

    Restaurants, cafeterias and similar dining facilities (including associated commercial kitchens)

    Taverns and bars

  • CBC § 903.2.1 High relevance — show source text

    [F] 903.2.1 Group A. An automatic sprinkler system shall be provided throughout buildings and portions thereof used as Group A occupancies as provided in this section.

    [F] 903.2.1.1 Group A-1. An automatic sprinkler system shall be provided throughout stories containing Group A-1 occupancies and throughout all stories from the Group A-1 occupancy to and including the levels of exit discharge serving that occupancy where one of the following conditions exists:

    1. The fire area exceeds 12,000 square feet (1115 m [2] ).
    2. The fire area has an occupant load of 300 or more.
    3. The fire area is located on a floor other than a level of exit discharge serving such occupancies.
    4. The fire area contains a multitheater complex.

    [F] 903.2.1.2 Group A-2. An automatic sprinkler system shall be provided throughout stories containing Group A-2 occupancies and throughout all stories from the Group A-2 occupancy to and including the levels of exit discharge serving that occupancy where one of the following conditions exists:

    1. The fire area exceeds 5,000 square feet (464 m [2] ).
    2. The fire area has an occupant load of 100 or more.
    3. The fire area is located on a floor other than a level of exit discharge serving such occupancies. 4. The structure exceeds 5,000 square feet (465 m [2] ), contains more than one fire area containing a Group A-2 occupancy, and is separated into two or more buildings by fire walls of not less than 4-hour fire-resistance rating without openings.

    [F] 903.2.1.3 Group A-3. An automatic sprinkler system shall be provided throughout stories containing Group A-3 occupancies and throughout all stories from the Group A-3 occupancy to and including the levels of exit discharge serving that occupancy where one of the following conditions exists:

    1. The fire area exceeds 12,000 square feet (1115 m [2] ).
    2. The fire area has an occupant load of 300 or more.
    3. The fire area is located on a floor other than a level of exit discharge serving such occupancies. 4. The structure exceeds 12,000 square feet (1155 m [2] ), contains more than one fire area containing exhibition and display rooms, and is separated into two or more buildings by fire walls of not less than 4-hour fire-resistance rating without openings.

    [F] 903.2.1.4 Group A-4. An automatic sprinkler system shall be provided throughout stories containing Group A-4 occupancies and throughout all stories from the Group A-4 occupancy to and including the levels of exit discharge serving that occupancy where one of the following conditions exists:

    1. The fire area exceeds 12,000 square feet (1115 m [2] ).
    2. The fire area has an occupant load of 300 or more.
    3. The fire area is located on a floor other than a level of exit discharge serving such occupancies.

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    FIRE PROTECTION AND LIFE SAFETY SYSTEMS

    [F] 903.2.1.5 Group A-5. An automatic sprinkler system shall be provided for all enclosed Group A-5 accessory use areas in excess of 1,000 square feet (93 m [2] ).

  • CBC § 2.1 High relevance — show source text
    1. 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 § 803.13 High relevance — show source text

    Incidental uses 509 Interior finishes Table 803.13, 804 Live load Table 1607.1 Means of egress Aisles 1018.3

    Stairway, exit access 1019 Travel distance 1006.3, 1017.2,

    1006.2.1

    Mixed occupancies 508.2, 508.3, 508.4 Accessory 303.1.2, 508.2 Ambulatory care facilities 422 Assembly 303.1.2

    Assembly spaces 1030 Exit signs 1013.1 Guards 1015.2, 1030.17 Main exit 1030.3

    Open air 1005.3.1, 1005.3.2, 1006.3, 1009.6.4, 1019.3, 1027, 1030.6.2 Panic hardware 1010.2.8, 1010.4.1 Smoke-protected 1005.3.1, 1005.3.2, 1006.3, 1009.6.4, 1019.3, 1027, 1030.6.2 Travel distance 1006.2.1, 1006.3, 1017.2, 1030.7 Mixed occupancies 508.3, 508.4 Accessory 508.2 Education 303.1.3

    Live/work units 508.5 Mall buildings 402 Other occupancies 303.1.1, 303.1.2, 303.1.3 Parking below/above 510.7, 510.9 Religious facilities 303.1.4 Special mixed 510.2 Motion picture theaters 409, 507.12 Occupancy exceptions 303.1.1, 303.1.2, 303.1.3, 303.1.4, 305.1.1, 305.2.1 Plumbing fixtures Chapter 29 Risk category Table 1604.5 Seating, fixed (see Seating, Fixed) Seating, open-air assembly seating 1030.6.3 Seating, smoke-protected 1030.6.2 Sprinkler protection 410, 504.3, 506.2, 507.12, 507.4, 507.6, 507.7, 903.2.1 Stages and platforms 410 Standpipes 905.3.2, 905.5.1 Unlimited area 507.12, 507.4, 507.4.1, 507.6, 507.7 Assisted Living (see Group I-1 and Group R-4) 308.2, 310.5, 420 Atmospheric Ice Loads 1614 Atrium 404

    Alarms and detection 404.4, 907.2.15 Enclosure 404.6, 707.3.6 Interior finish 404.8 Means of egress 404.9, 404.10, 404.11, 1006.3.2, 1017.3, 1019.3, 1023.2,

    1028.2

    Smoke control 404.5, 909 Sprinkler protection 404.3 Standby power 404.7 Travel distance 404.9, 1006.2.1, 1006.3, 1017.2

    Use 404.2

    Attic 202

  • CBC § 709.4.2 Medium relevance — show source text

    Requirements 709.4.2, 1009.6 Signage 1009.10, 1009.11, 1009.9, 1013.4, 1143A, 11B-216, 11B-703 Two-way communication 1009.6.5, 1009.8, 1026.6 Where required 1009.2, 1009.3.3, 1009.4.2 Assembly Occupancy (Group A) 303, 1030 Accessibility Chapters 11A and 11B Alarms and detection 907.2.1

    Area 503, 506, 507, 508 Bleachers (see Bleachers) Folding and telescopic seating (see Bleachers) General 303.1 Grandstands (see Grandstands) Group-specific provisions A-1 303.2

    A-2 303.3

    A-3 303.4

    A-4 303.5

    Motion picture theater 409, 507.12 Special amusement areas 411 Stages and platforms 410 Height 503, 504, 505, 508, 510 Incidental uses 509 Interior finishes Table 803.13, 804 Live load Table 1607.1 Means of egress Aisles 1018.2, 1030.9, 1030.10,

    1030.11

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    INDEX

    Limitations on authority 113.2 Membership of board B101.3 Notice of meeting B101.5 Qualifications 113.3, B101.3.1 Boiler Room

    Exits 1006.2.2.1

    Bolts

    Anchor rods 1901.3 Bonding, Masonry 1805.2.2, 2103.2.2, 2113.3.1, 2510.7 Bottle-Filling Stations 202 Braced Wall Line 202

    Bracing 2308.10 Seismic requirements 2308.10.10.2, 2308.10.6.2, 2308.10.8 Sill anchorage 2308.10.7.3 Spacing 2308.10.1 Support 2308.10.8 Temporary 3103.5 Braced Wall Panel 202 Alternative bracing 2308.10.5.1, 2308.10.5.2

    Connections 2308.10.7 Length 2308.10.4 Location 2308.10.2

    Method 2308.10.3 Brick (see Masonry) Building Area (see Area, Building) 502.1, 503, 505, 506, 507, 508, 510 Demolition 3303

    Existing 101.4.7 Fire walls 706.1 Height (see Height, Building) 502.1, 503, 504, 505, 508, 510 Occupancy classification Chapter 3 Party walls 706.1.1 Relocatable 3113

    Replicable Appendix N Building, Existing 202 Building Department 103 Building Official Duties and powers 103, 104 Qualifications Appendix A Records 104.7

  • CBC § 2.1 Medium relevance — show source text

    The IBC requirements for hazardous materials, fire-resistance-rated construction, interior finish, fire protection systems, means of egress, emergency and standby power, and temporary structures are directly correlated with the requirements of the International Fire Code ® (IFC®). The following table shows chapters/sections of the IBC that are correlated with the IFC:

    IBC/IFC CORRELATED TOPICS Col2 Col3
    IBC CHAPTER/SECTION IFC CHAPTER/SECTION SUBJECT
    Sections 307, 414, 415 Chapters 50–67 Hazardous materials and Group H requirements
    Chapter 7 Chapter 7 Fire-resistance-rated construction (fire and smoke protection features in the IFC)
    Chapter 8 Chapter 8 Interior finish, decorative materials and furnishings
    Chapter 9 Chapter 9 Fire protection systems
    Chapter 10 Chapter 10 Means of egress
    Chapter 27 Section 604 Standby and emergency power
    Section 3103 Chapter 31 Temporary structures

    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 Occupancy Classification and Use.

    Chapter 3 provides for the classification of buildings, structures and parts thereof based on the purpose for which they are used. Section 302 identifies the groups into which all buildings, structures and parts thereof must be classified. Sections 303 through 312 identify the occupancy characteristics of each group classification. In some sections, specific group classifications having requirements in common are collectively organized such that one term applies to all. For example, Groups A-1, A-2, A-3, A-4 and A-5 are individual groups for assembly-type buildings. The general term “Group A,” however, includes each of these individual groups. Other groups include Business (B), Organized Camps (C), Educational (E), Factory (F-1, F-2), High Hazard (H-1, H-2, H-3, H-4, H-5), Institutional (I-2, I-3, I-4), Laboratories (L), Mercantile (M), Residential (R-1, R-2, R-2.1, R-2.2, R-3, R-3.1, R-4), Storage (S-1, S-2) and Utility (U). In some occupancies, the smaller number means a higher hazard, but that is not always the case.

  • CBC § 101.4.7 Medium relevance — show source text

    Existing 101.4.7 Fire walls 706.1 Height (see Height, Building) 502.1, 503, 504, 505, 508, 510 Occupancy classification Chapter 3 Party walls 706.1.1 Relocatable 3113

    Replicable Appendix N Building, Existing 202 Building Department 103 Building Official Duties and powers 103, 104 Qualifications Appendix A Records 104.7

    Termination A101.4 Building-Integrated Photovoltaic (BIPV) (see Photovoltaic) Built-Up Roof 1507.10 Business Occupancy (Group B) 303.1.1, 303.1.2, 304 Alarms and detection 907.2.2 Ambulatory care facilities 304, 422 Area 503, 505, 506, 507, 508 Height 503, 504, 505, 508, 510 Higher education laboratories 428, 2702.2

    Incidental uses 509 Interior finishes Table 803.13, 804 Live load Table 1607.1 Means of egress Aisles 1018.3

    Stairway, exit access 1019 Travel distance 1006.3, 1017.2,

    1006.2.1

    Mixed occupancies 508.2, 508.3, 508.4 Accessory 303.1.2, 508.2 Ambulatory care facilities 422 Assembly 303.1.2

    Assembly spaces 1030 Exit signs 1013.1 Guards 1015.2, 1030.17 Main exit 1030.3

    Open air 1005.3.1, 1005.3.2, 1006.3, 1009.6.4, 1019.3, 1027, 1030.6.2 Panic hardware 1010.2.8, 1010.4.1 Smoke-protected 1005.3.1, 1005.3.2, 1006.3, 1009.6.4, 1019.3, 1027, 1030.6.2 Travel distance 1006.2.1, 1006.3, 1017.2, 1030.7 Mixed occupancies 508.3, 508.4 Accessory 508.2 Education 303.1.3

  • CBC § 2.1. Medium relevance — show source text
    1. Fire partitions serving as a corridor wall shall not be required to extend above the lower membrane of a corridor ceiling provided that the corridor ceiling membrane is equivalent to corridor wall membrane, and either of the following conditions is met:

    2.1. The room-side membrane of the corridor wall extends to the underside of the floor or roof sheathing, deck or slab of a fire-resistance-rated floor or roof above.

    2.2. The building is equipped with an automatic sprinkler system installed throughout in accordance with Section 903.3.1.1 or 903.3.1.2, including automatic sprinklers installed in the space between the top of the fire partition and underside of the floor or roof sheathing, deck or slab above. 3. Fire partitions serving as a corridor wall shall be permitted to terminate at the upper membrane of the corridor ceiling assembly where the corridor ceiling is constructed as required for the corridor wall. 4. Fire partitions separating tenant spaces in a covered or open mall building complying with Section 402.4.2.1 shall not be required to extend above the underside of a ceiling. Such ceiling shall not be required to be part of a fire-resistance-rated assembly, and the attic or space above the ceiling at tenant separation walls shall not be required to be subdivided by fire partitions.

    708.4.1 Fire partition walls enclosing elevator lobbies. Fire partition walls used to enclose elevator lobbies in accordance with Section 3006.3 shall form an enclosure that terminates at a fire barrier or fire partition having a fire-resistance rating of not less than 1 hour, or an outside wall.

    708.4.2 Supporting construction. The supporting construction for a fire partition shall have a fire-resistance rating that is equal to or greater than the required fire-resistance rating of the supported fire partition.

    Exception: In buildings of Types IIB, IIIB and VB construction, the supporting construction requirement shall not apply to fire partitions separating tenant spaces in covered and open mall buildings, fire partitions separating dwelling units, fire partitions separating sleeping units, fire partitions serving as corridor walls, fire partitions separating ambulatory care facilities from adjacent spaces or corridors, fire partitions separating dwelling and sleeping units from Group R-1 and R-2 occupancies and fire partitions separating vestibules from the level of exit discharge.

    708.4.3 Fireblocks and draftstops in combustible construction. In combustible construction where fire partitions do not extend to the underside of the floor or roof sheathing, deck or slab above, the space above and along the line of the fire partition shall be provided with one of the following:

    1. Fireblocking up to the underside of the floor or roof sheathing, deck or slab above using materials complying with Section 718.2.1.

    2. Draftstops up to the underside of the floor or roof sheathing, deck or slab above using materials complying with Section 718.3.1 for floors or Section 718.4.1 for attics.

    Exceptions:

    1. Buildings equipped with an automatic sprinkler system installed throughout in accordance with Section 903.3.1.1, or in accordance with Section 903.3.1.2 provided that protection is provided in the space between the top of the fire partition and underside of the floor or roof sheathing, deck or slab above as required for systems complying with Section 903.3.1.1.

    2. Where corridor walls provide a sleeping unit or dwelling unit separation, draftstops shall only be required above one of the corridor walls.

  • CBC § 805.4.2.3 Medium relevance — show source text

    805.4.2.3 Smoke control testing 909.18.8.3 Temporary special event structure 3105.5.1 Arc Welding (see Welding and Other Hot Work) Area of Refuge (see Accessible Means of Egress) 202, 1009.6 Array (storage) 3205.8, 3207.4 Defined 202 Array, Closed (storage) 202, 3205.8, 3207.4 Artificial Barricade (see Barricade) Artificial Combustible Vegetation 321 Ash Trays 310.6 Ashes, Hot 305.2 Asphalt (Tar) Kettles 303, 3305.10.1 Asphyxiant Gases 5004.7.1, 5307.1 Assembly Occupancies (Group A) 203 Announcements 403.2.2

    Automatic sprinklers 903.2 Candles 308 Cellulose nitrate film 105.5.6, 306 Decorative materials 806, 807 Defined (Occupancy classification) 202 Emergency evacuation drill 405 Employee training 406 Evacuation plans 404 Fire alarm systems 907.2.1 Fire safety plans 404 Furnishings 807.5.1 Interior finish 803

    LP-gas installations Chapter 61 Means of egress 1030 Aisles 1018.2, 1030.9, 1030.10,

    1030.11

    Exit signs 1013.1 Guards 1015.2, 1030.17 Main exit 1030.3

    Open air 1005.3.1, 1005.3.2, 1006.3, 1009.6.4, 1019.3, 1027,

    1030.6.2

    Panic hardware 1010.2.8, 1010.4.1 Smoke-protected 1005.3.1, 1005.3.2, 1006.3, 1009.6.4, 1019.3, 1027, 1030.6.2 Travel distance 1017.2, 1006.3, 1030.7, 1006.2.1 Motion picture projection rooms 306.1 Multiple fire areas 903.2.1.7 Obstruction of exits 1032.3

    Occupant load calculation 1004 On roofs 903.2.1.6 Open-flame devices 308.3 Panic hardware 1010.2.8

    Permits required 105.5.40 Portable fire extinguishers 906 Posting maximum occupant load 1004.3 Prohibit smoking 310 Pyroxylin plastic motion picture film storage 306.1 Pyroxylin-coated fabric 807.5.1.4 Seating 1030 Seating plan 403.2.1 Standpipe systems 905 Storage, flammable liquids 5704.3.4.2 Tents Chapter 31 Vehicles in 3108.14.4 Assisted Rescue Areas, Exterior (see Exterior Areas of Assisted Rescue) Atrium 202 Means of egress 1006.3.2, 1017.3, 1019.3, 1023.2, 1028.2 Sprinklers 914.4.

  • CBC § 7.2 Medium relevance — show source text

    7.2|—|—|—|—|—|—|—|—|—|—|—|—|—|R|—|—|—|—|—|—|—|—|—| |1103.7.3|—|—|—|—|—|—|—|—|—|—|—|—|—|—|R|—|—|—|—|—|—|—|—| |1103.7.4|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|R|—|—|—|—|—|—|—| |1103.7.5|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|R|—|—|—|—| |1103.7.6|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|R|—|—|—| |1103.8|—|—|—|—|—|—|—|—|—|—|—|—|—|R|—|—|—|—|R|R|R|R|—| |1103.9|R|—|—|—|—|—|—|—|—|—|—|—|—|R|R|—|R|—|R|R|R|R|—| |1103.10|—|—|—|—|—|—|—|—|—|—|—|—|—|R|R|—|—|—|—|—|—|—|—| |1104|R|R|R|—|R|R|R|R|R|R|R|R|R|R|R|R|R|R|R|R|R|R|R| |1105|—|—|—|—|—|—|—|—|—|—|—|—|—|—|R|—|—|—|—|—|—|—|—| |1106|—|—|—|R|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—|—| |R = The building is required to comply.
    a.
    Existing buildings shall comply with the sections identified as “Required” (R) based on occupancy classification or use, or both, whichever is applicable.
    b.
    Only applies to Group I-2, Condition 2 occupancies as established by the adopting ordinance or legislation of the jurisdiction.
    c.
    Only applies to Group A-2 occupancies where alcoholic beverages are consumed.|R = The building is required to comply.
    a.
    Existing buildings shall comply with the sections identified as “Required” (R) based on occupancy classification or use, or both, whichever is applicable.
    b.
    Only applies to Group I-2, Condition 2 occupancies as established by the adopting ordinance or legislation of the jurisdiction.
    c.
    Only applies to Group A-2 occupancies where alcoholic beverages are consumed.|R = The building is required to comply.
    a.
    Existing buildings shall comply with the sections identified as “Required” (R) based on occupancy classification or use, or both, whichever is applicable.
    b.
    Only applies to Group I-2,

  • CBC § 203.1 Medium relevance — show source text

    [BG] YARD. An open space, other than a court, unobstructed from the ground to the sky, except where specifically provided by the California Building Code, on the lot on which a building is situated.

    ZONE. A defined area within the protected premises. A zone can define an area from which a signal can be received, an area to which a signal can be sent or an area in which a form of control can be executed.

    ZONE, NOTIFICATION. An area within a building or facility covered by notification appliances which are activated simultaneously.

    SECTION 203—OCCUPANCY CLASSIFICATION AND USE

    [BG] 203.1 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 of the California Building Code . 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 of the California Building Code .

    1. Assembly: Groups A-1, A-2, A-3, A-4 and A-5.

    2. Business: Group B.

    3. Educational: Group E.

    4. Factory and Industrial: Groups F-1 and F-2.

    5. High Hazard: Groups H-1, H-2, H-3, H-4 and H-5.

    6. Institutional: Groups I-1, I-2, I-3 and I-4.

    7. Mercantile: Group M.

    8. Residential: Groups R-1, R-2, R-3 and R-4.

    9. Storage: Groups S-1 and S-2.

    10. Utility and Miscellaneous: Group U.

    [BG] 203.1.1 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 203.1. Certain uses require specific limitations and controls in accordance with the provisions of this code and Chapter 4 of the California Building Code .

    [BG] 203.2 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 or Motion Picture and Television Production Studio Sound Stages, Approved Production Facilities and produc- tion locations. Any building or structure or portion thereof used or intended to be used 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.

    [BG] 203.2.1 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.

Frequently asked questions

When do I treat a space as Group B instead of Group A?

If the entire building or tenant space used for assembly has an occupant load less than 50, classify it as Group B per § 303.1.1. Also, accessory assembly rooms with occupant load <50 or area <750 sq ft may be treated as part of the host occupancy per § 303.1.2 .

Does the showing of a movie always make a room Group A?

No — the motion‑picture clause in § 303.1 specifies that showing motion pictures counts as Group A when the building is open to the public and has a capacity of 10 or more persons. For other assembly uses, the 50‑person tenant/building threshold in § 303.1.1 controls classification .

If a small assembly room is inside a school (Group E), do I classify it separately?

No — a room or space used for assembly that is associated with a Group E occupancy is not considered a separate occupancy under § 303.1.3 .

What about small religious classrooms or auditoriums?

Accessory religious educational rooms and religious auditoriums with occupant loads less than 100 per room/space are not considered separate occupancies under § 303.1.4 — note this is a different (higher) threshold specific to religious facilities .

Who decides when a borderline case (e.g., occupant load = 50) changes classification?

The building official / authority having jurisdiction issues the formal classification; document your occupant‑load calculation and submit it with plans. If occupancy meets or exceeds the numeric threshold in the code, expect Group A requirements to apply (and notify the authority as required) — see § 303.1.1 and related provisions .

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Related in the CBC

Residential Group R — R‑1, R‑2, R‑3, R‑4 distinctions

Institutional Group I — classifications and I‑4 (day care) rules

Assembly, Residential & Institutional occupancies

California Building Code