Chapter 3 — OCCUPANCY CLASSIFICATION AND USE
Section 310
California Building Code (Title 24, Part 2) · 2019 edition · updated 2026-09-12 · California
Italicized text is a California amendment to the model code, as printed in the official publication.
310.1 Residential Group R.¶
Residential Group R includes, among others, the use of a building or structure, or a portion thereof, for sleeping purposes when not classified as an Institutional Group I or when not regulated by the California Res- idential Code .
310.2 Residential Group R-1.¶
Residential Group R-1 occupancies containing sleeping units where the occupants are primarily transient in nature, including:
Boarding houses (transient) with more than 10 occupants Congregate residences (transient) with more than 10
occupants Hotels (transient) Motels (transient)
[HCD 1] Efficiency dwelling units (transient)
310.3 Residential Group R-2.¶
Residential Group R-2 occupancies containing sleeping units or more than two dwelling units where the occupants are primarily permanent in nature, including:
OCCUPANCY CLASSIFICATION AND USE
Apartment houses Congregate residences (nontransient) with more
than 16 occupants
Boarding houses (nontransient) Convents Dormitories Fraternities and sororities Monasteries Hotels (nontransient) Live/work units Motels (nontransient) Vacation timeshare properties
[HCD 1] Efficiency dwelling units (transient)
310.3.1 Residential Group R-2.1. Residential Group R- 2.1 occupancies shall include buildings, structures or parts thereof housing clients, on a 24-hour basis, who because of age, mental disability or other reasons, live in a supervised residential environment that provides per- sonal care services.
This occupancy may contain more than six nonambula- tory and/or bedridden clients. (See Section 435 Special Provisions for Licensed 24-Hour Care Facilities in a Group R-2.1, R-3.1 or R-4 Occupancy). This group shall include, but not be limited to, the following:
Assisted living facilities such as:
Residential care facilities, Residential care facilities for the elderly (RCFEs), Adult residential facilities, Congregate living health facilities, Group homes, Residential care facilities for the chronically ill, Congregate living health facilities for the terminally ill.
Social rehabilitation facilities such as:
Halfway houses, Community correctional centers, Community correction reentry centers, Community treatment programs, Work furlough programs, Alcoholism or drug abuse recovery or treatment
facilities.
310.3.2 Residential Group R-2.2 (CDCR Only). Residen- tial occupancies operated by CDCR in a community located facility that provides housing and community- based program services for nontransient ambulatory par- ticipants in a nonlicensed facility with 24/7 supervision.
310.4 Residential Group R-3.¶
Residential Group R-3 occupancies where the occupants are primarily permanent in nature and not classified as Group R-1, R-2, R-2.1, R-2.2, R-3.1, R-4 or I, including:
Buildings that do not contain more than two dwelling units Congregate residences (nontransient) with 16 or fewer occupants
Boarding houses (nontransient) Convents Dormitories Fraternities and sororities Monasteries
Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.
100735044
prevention of fire or for the protection of life and property against fire and panic unless the requirement would be applicable to a structure regardless of the special occu- pancy. Nothing shall restrict the application of state or local housing standards to such facilities if the standards are applicable to residential occupancies and are not based on the use of the structure as a facility for ambula- tory children. For the purpose of this exception, ambula- tory children do not include relatives of the licensee or the licensee’s spouse.
310.4.2 Lodging houses. Owner-occupied lodging houses with five or fewer guest rooms and 10 or fewer total occupants shall be permitted to be constructed in accordance with the California Residential Code .
310.5 Residential Group R-4.¶
Residential Group R-4 occupancy shall include buildings, structures or portions thereof for more than six ambulatory clients, but not more than 16 persons, excluding staff, who reside on a 24-hour basis in a supervised residential environment and receive custodial care. This group shall include, but not be limited to, the following:
Group R-4 occupancies shall meet the requirements for construction as defined for Group R-3, except as otherwise provided for in this code. This occupancy classification may include a maximum six nonambulatory or bedridden clients (see Section 435, Special Provisions for Licensed 24-Hour Care Facilities in a Group R-2.1, R-3.1 or R-4). Group R-4 occupancies shall meet the requirements in Section 420.
310.6 Large family day-care homes.¶
See Section 455.
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Ask AI about this code▸Contents — California Building Code (Title 24, Part 2)
- Chapter 2 — DEFINITIONS AND ABBREVIATIONS
- Appendix G — FLOOD-RESISTANT
- Appendix L — EARTHQUAKE RECORDING
- Appendix M — TSUNAMI-GENERATED
- Chapter 1 — SCOPE AND ADMINISTRATION
▸Chapter 3 — OCCUPANCY CLASSIFICATION AND USE
- Chapter 4 — SPECIAL DETAILED REQUIREMENTS BASED
- Chapter 5 — GENERAL BUILDING HEIGHTS AND AREAS
- Chapter 6 — TYPES OF CONSTRUCTION
- Chapter 7 — FIRE AND SMOKE PROTECTION FEATURES
- Chapter 7A — MATERIALS AND CONSTRUCTION
- Chapter 8 — INTERIOR FINISHES
- Chapter 9 — FIRE PROTECTION AND LIFE SAFETY SYSTEMS
- Chapter 10 — MEANS OF EGRESS
- Chapter 11A — HOUSING ACCESSIBILITY
- Chapter 11B — ACCESSIBILITY TO PUBLIC BUILDINGS, PUBLIC ACCOMM…
- Chapter 12 — INTERIOR ENVIRONMENT
- Chapter 14 — EXTERIOR WALLS
- Chapter 15 — ROOF ASSEMBLIES AND ROOFTOP STRUCTURES
- Chapter 16 — STRUCTURAL DESIGN
- Chapter 16A — STRUCTURAL DESIGN
- Chapter 17 — SPECIAL INSPECTIONS AND TESTS
- Chapter 18 — SOILS AND FOUNDATIONS
- Chapter 19 — CONCRETE
- Chapter 20 — ALUMINUM
- Chapter 21 — MASONRY
- Chapter 22 — STEEL
- Chapter 23 — WOOD
- Chapter 24 — GLASS AND GLAZING
- Chapter 25 — GYPSUM BOARD, GYPSUM PANEL PRODUCTS AND PLASTER
- Chapter 26 — PLASTIC
- Chapter 27 — ELECTRICAL
- Chapter 28 — MECHANICAL SYSTEMS
- Chapter 30 — ELEVATORS AND CONVEYING SYSTEMS
- Chapter 31 — SPECIAL CONSTRUCTION
- Chapter 31B — PUBLIC POOLS
- Chapter 31C — RADIATION
- Chapter 31D — FOOD ESTABLISHMENTS
- Chapter 31F — MARINE OIL TERMINALS
- Chapter 32 — ENCROACHMENTS INTO THE PUBLIC RIGHT-OF-WAY
- Chapter 33 — SAFEGUARDS DURING CONSTRUCTION
- Chapter 35 — REFERENCED STANDARDS
- Appendix A — EMPLOYEE QUALIFICATIONS
- Appendix B — BOARD OF APPEALS
- Appendix C — GROUP U – AGRICULTURAL BUILDINGS
- Appendix D — FIRE DISTRICTS
- Appendix F — RODENTPROOFING
- Appendix H — SIGNS
- Appendix I — PATIO COVERS
- Appendix J — GRADING
- Appendix K — GROUP R-3 AND GROUP R-3.1 OCCUPANCIES
- Appendix N — REPLICABLE BUILDINGS
- Appendix O — EMERGENCY HOUSING