CBC · California Building Code

What upgrades are required when a building or portion changes occupancy?

When a building or part of it changes use or occupancy classification you must follow the CEBC rules for the new use (Chapter 6 and Sections 1002–1011). That usually means checking fire protection, means of egress, structural (live load/seismic), plumbing, mechanical and electrical systems and obtaining a new certificate of occupancy when the classification changes; some limited exceptions (e.g., area <10%, cumulative changes considered) apply. The specific triggers and exceptions are in § 1001.2.1, § 1001.3, § 1002.1 and the change‑of‑occupancy provisions in Sections 1003–1011 .

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

When a building or portion of a building is changed in use or in occupancy classification, the work must meet the applicable requirements for the new use (Chapter 6 work classification plus Sections 1002–1010) and a new certificate of occupancy is required when the classification changes (§ 1001.2.1; § 1001.3) . Where the change involves a special occupancy listed in Chapter 4 the building must comply with those Chapter 4 requirements (§ 1002.1) . The Existing Building provisions then identify specific systems and elements (fire protection, egress, structural, MEP, interior finish, etc.) that must be upgraded or provided where the change triggers them (see especially Section 1011 and the structural triggers in Chapter 10) .

Requirements in detail

The CEBC treats “change in use” (different function within same occupancy) and “change of occupancy classification” slightly differently, but both require evaluation against the code provisions for the proposed use and certain mandatory upgrades. The controlling high‑level rules are § 1001.2.1, § 1001.3 and § 1002.1; the detailed upgrade triggers live in Sections 1003–1011 and Chapter 13 where adopted. The table below simplifies the decision dimensions you use when determining required upgrades.

Decision dimension Key threshold or value What it controls / requires Code reference
Is the work a “change in use” (function) or a change in occupancy classification? N/A — determine by Chapter 3 occupancy rules Work must conform to Chapter 6 classification rules and Sections 1002–1010 for the new use (§ 1001.2.1) § 1001.2.1
Does the change produce a different occupancy classification? Yes/No A new certificate of occupancy is required when classification changes (§ 1001.3) § 1001.3
New occupancy is a “special occupancy” in Chapter 4? Yes/No Must comply with all applicable Chapter 4 requirements (§ 1002.1) § 1002.1
Area of the new occupancy as % of building < 10% / ≥ 10% Several structural/seismic and other upgrade exemptions apply when the new area is less than 10% (cumulative changes considered) § 1006.2 / § 1006.3 & related exceptions
Change of occupancy → different Chapter 9 threshold? Yes/No If Chapter 9 for the new occupancy requires sprinklers or alarm, those systems must be provided in the change area and non-separated areas (§ 1011.2.1, § 1011.2.2) § 1011.2.1; § 1011.2.2
Increase in occupant load for plumbing > 20% increase in story occupant load Provide plumbing fixtures per California Plumbing Code based on the increased occupant load (exception allows omission if ≤20%) § 1009.1
Electrical service needs New occupancy Electrical service shall be upgraded to meet California Electrical Code requirements for the new occupancy; correct unsafe conditions (§ 1007.1–1007.3) § 1007.1; § 1007.2; § 1007.3
Structural live loads Design live loads per new use (Section 1607 CBC) Structural elements serving the area of occupancy change must satisfy CBC live‑load requirements; small increases (≤5% D/C ratio) may be excepted § 1006.1 (and related)
Means of egress when changing to a higher hazard Change to higher‑hazard category (see Table 1011.5) Egress must comply with CBC Chapter 10 when moving to a higher hazard category; egress capacity must meet new occupant load (§ 1011.5, § 1011.5.3) § 1011.5; § 1011.5.3
Interior finish Areas undergoing the change Interior wall/ceiling finish must comply with the new occupancy classification requirements (§ 1011.3) § 1011.3
Emergency escape & rescue openings When new occupancy requires them Existing operable windows used for EER openings must meet minimum clear opening sizes or be replaced per the code rules (§ 506.4 / 1011.5.6) § 506.4; § 1011.5.6

Fire protection and alarm

  • If the new occupancy or occupancy change causes a different Chapter 9 threshold (for example the new classification requires sprinklers or a fire alarm) those systems must be installed in the change area and in any part of the building not separated by a firewall from that area (§ 1011.2.1; § 1011.2.2) . The code also allows the code official to authorize removal of a previously installed sprinkler system under narrow conditions (§ 1011.2.1.1) .

Means of egress

  • Where the change moves the space into a higher hazard category (Table 1011.5), provide means of egress in accordance with Chapter 10 of the CBC; egress capacity must meet the new occupant load (§ 1011.5; § 1011.5.3) .

Structural (loads, seismic, wind, snow)

  • Structural elements that carry live loads for the new occupancy must comply with Section 1607 (design live loads). Small increases where the demand‑capacity ratio rises by ≤5% are excepted (§ 1006.1) .
  • If the change of occupancy assigns the building to a higher Risk Category, the building’s lateral force‑resisting system and applicable snow/wind requirements must be upgraded for the new risk category (exceptions apply when the new area is less than 10% of building area or other limited exceptions) (§ 1006.2; § 1006.3 and related exceptions) .

Mechanical, plumbing, electrical

  • Mechanical ventilation or kitchen exhaust differences in the new occupancy must be corrected per the California Mechanical Code (§ 1008.1) .
  • Plumbing: if the story occupant load is increased by more than 20%, provide plumbing fixtures per the California Plumbing Code based on the increased occupant load; food handling occupancies impose additional sanitary protections (§ 1009.1–1009.4) .
  • Electrical: unsafe conditions must be corrected, and electrical service shall be upgraded to meet requirements for the new occupancy (§ 1007.2–1007.3) .

Interior finish and acoustics

  • Interior finish for walls and ceilings in the change area must meet the finish requirements for the new occupancy classification (§ 1011.3) .
  • Special provisions such as enhanced classroom acoustics in Group E for Level 3 work are specified where applicable (§ 1011.3 / related Level 3 provisions) .

Exceptions & special cases

  • Area less than 10%: Several upgrade triggers (notably some structural/seismic and snow/wind requirements) are not required when the new occupancy area is less than 10% of the building area — but the code requires consideration of cumulative occupancy changes over time (§ 1006.2, § 1006.3 and related exceptions) .
  • Partial change separated by fire barriers: If the portion changed is separated from the remainder with the required fire‑resistance assemblies, only the separated portion needs to be evaluated for compliance; if not separated, applicable provisions for each occupancy apply to the entire building and the more restrictive requirements govern (§ 1302.1.2) .
  • Special occupancies (Chapter 4): A change into a Chapter 4 special occupancy (for example certain assembly, institutional, hazardous occupancies) requires compliance with the specific Chapter 4 rules (§ 1002.1) .
  • Fire protection removal: The code official may permit removal of an existing sprinkler system only when narrow criteria are met and documentation is approved (§ 1011.2.1.1) .
  • Seismic exceptions: For some reclassifications to Risk Category III where S_DS < 0.33, or where the area of new occupancy is less than 10% and other conditions are met, the seismic upgrade requirement may not apply (§ 1006.3 exceptions) .

Common mistakes

  • Treating “change in use” (function) and “change of occupancy classification” as the same — they have different triggers and scopes (see § 1001.2.1 and § 1011) .
  • Assuming the <10% rule is an absolute “free pass.” The code requires you to consider cumulative changes and other exceptions; multiple small changes can add up and remove the exemption (§ 1006.x exceptions) .
  • Forgetting the certificate of occupancy when classification changes — you must obtain a CO when the occupancy classification changes (§ 1001.3) .
  • Overlooking MEP or plumbing triggers tied to occupant load or to the specific new use (e.g., food handling or grease production requires specific plumbing/equipment) (§ 1009.1–1009.4; § 1007) .
  • Not verifying whether the change area is separated by rated construction — separation changes which parts of the building must be brought into compliance (§ 1302.1.2) .

Worked example — concrete scenario

Scenario: 5,000 ft² single‑story storage building (Group S) — owner proposes to convert 700 ft² to a retail sales area (Group B) that is not separated by a fire barrier.

  1. Calculate percentage: 700 / 5,000 = 14% → greater than the 10% threshold. The <10% exception does not apply. (See the <10% exception language in the structural/seismic provisions.) (§ 1006.3 exceptions) .

  2. Structural/seismic: Because the change is from Group S to a different occupancy and the change area is ≥10%, the lateral force‑resisting system must be evaluated and upgraded for the new risk category as required (§ 1006.3) .

  3. Fire protection: Determine whether Chapter 9 sprinklers or alarm thresholds apply to the new Group B area. If Chapter 9 would require sprinklers or an alarm for the new occupancy, the system must be installed in the change area and in any building area not separated by a firewall (no separation here) (§ 1011.2.1; § 1011.2.2) .

  4. Electrical: Upgrade electrical service to meet the California Electrical Code requirements for the new occupancy (retail may need different service capacity) and correct any unsafe conditions (§ 1007.2–1007.3) .

  5. Plumbing: If the change increases the occupant load on that story by more than 20%, provide plumbing fixtures per the California Plumbing Code. (Calculate new occupant loads based on CBC occupant load factors.) (§ 1009.1) .

  6. Means of egress: Confirm whether the change raises hazard category (Table 1011.5). If it is a higher‑hazard move, means of egress must comply with Chapter 10 and egress capacity must meet the new occupant load (§ 1011.5; § 1011.5.3) .

  7. Certificate of occupancy: When the new occupancy classification is established, a certificate of occupancy must be issued (§ 1001.3) .

This example shows the workflow: compute area and percent, determine separation, check Chapter 9 thresholds, evaluate structural/seismic triggers, then MEP/egress/plumbing, then obtain CO.

Related provisions

  • § 1001.2.1 — Change of use (Chapter 6 and Sections 1002–1010 apply)
  • § 1001.3 — Certificate of occupancy required when classification changes
  • § 1002.1 — Special occupancies (Chapter 4) compliance for changes into special uses
  • § 1006.1–1006.3 — Structural live loads and seismic/wind/snow triggers when occupancy changes (exceptions noted)
  • § 1007.1–1007.3 — Electrical requirements, unsafe conditions, service upgrade when occupancy changes
  • § 1009.1–1009.4 — Plumbing fixture and sanitary requirements when occupancy changes (including food handling)
  • § 1011.1–1011.5 — Detailed change‑of‑occupancy classification provisions (fire protection, alarm, interior finish, egress hazard categories)
  • § 1302.1.2 — Partial change separated by fire barriers; only the separated portion may need evaluation (or entire building if not separated)

Code references

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

  • CBC § 1302.1 High relevance — show source text

    SECTION 1302—APPLICABILITY

    1302.1 General. Existing buildings in which there is work involving additions, alterations or changes of occupancy shall be made to conform to the requirements of this chapter or the provisions of Chapters 6 through 12. The provisions of Sections 1302.1.1 through 1302.1.6 shall apply to existing occupancies that will continue to be, or are proposed to be, in Groups A, B, E, F, I-2, M, R and S. These provisions shall also apply to Group U occupancies where such occupancies are undergoing a change of occupancy or a partial change in occupancy with separations in accordance with Section 1302.1.2. These provisions shall not apply to buildings with occupancies in Group H, I-1, I-3 or I-4.

    1302.1.1 Change in occupancy. Where an existing building is changed to a new occupancy classification and this section is applicable, the provisions of this section for the new occupancy shall be used to determine compliance with this code.

    1302.1.2 Partial change in occupancy. Where a portion of the building is changed to a new occupancy classification and that portion is separated from the remainder of the building with fire barrier or horizontal assemblies having a fire-resistance rating as required by Table 508.4 of the International Building Code or Section R302 of the International Residential Code for the separate occupancies, or with approved compliance alternatives, the portion changed shall be made to conform to the provisions of this section. Only the portion separated shall be required to be evaluated for compliance.

    Where a portion of the building is changed to a new occupancy classification and that portion is not separated from the remainder of the building with fire barriers or horizontal assemblies having a fire-resistance rating as required by Table 508.4 of the International Building Code or Section R302 of the International Residential Code for the separate occupancies, or with approved compliance alternatives, the provisions of this section which apply to each occupancy shall apply to the entire building. Where there are conflicting provisions, those requirements which secure the greater public safety shall apply to the entire building or structure.

    1302.1.3 Additions. Additions to existing buildings shall comply with the requirements of the International Building Code or the International Residential Code for new construction. The combined height and area of the existing building and the new addition shall not exceed the height and area allowed by Chapter 5 of the International Building Code . Where a fire wall that complies with Section 706 of the International Building Code is provided between the addition and the existing building, the addition shall be considered a separate building. Where a new occupiable roof is added to a building or structure, the occupiable roof shall comply with the provisions of the International Building Code .

    Exception: In-filling of floor openings and nonoccupiable appendages, such as elevator and exit stairway shafts, shall be permitted beyond that permitted by the International Building Code .

    1302.1.4 Alterations. An existing building or portion thereof shall not be altered in such a manner that results in the building being less safe or sanitary than such building is currently.

    Exception: Where the current level of safety or sanitation is proposed to be reduced, the portion altered shall conform to the requirements of the International Building Code .

    1302.1.5 Escalators. Where escalators are provided in below-grade transportation stations, existing and new escalators shall be permitted to have a clear width of less than 32 inches (815 mm).

  • CBC § 1006.3 High relevance — show source text

    Exception: Where the area of the new occupancy is less than 10 percent of the building area. The cumulative effect of occupancy changes over time shall be considered.

    [BS] 1006.3 Seismic loads. Where a change of occupancy results in a building being assigned to a higher risk category, or where the change is from a Group S or Group U occupancy to any occupancy other than Group S or Group U, the lateral force-resisting system of the building shall comply with Section 304.3.1 for the new risk category. Where a change of occupancy results in a building being assigned to Risk Category IV and Seismic Design Category D or F, nonstructural components serving any portion of the building changed to Risk Category IV shall comply with the requirements of Section 1613 of the California Building Code or shall comply with ASCE 41 using an objective of operational nonstructural performance with the BSE-1N earthquake hazard level.

    Exceptions:

    1. Where a change of use results in a building being reclassified from Risk Category I or II to Risk Category III and the seismic coefficient, S DS, is less than 0.33, compliance with this section is not required.

    2. Where the area of the new occupancy is less than 10 percent of the building area, the occupancy is not changing from a Group S or Group U occupancy, and the new occupancy is not assigned to Risk Category IV, compliance with this section is not required. The cumulative effect of occupancy changes over time shall be considered.

    3. Reserved.

    4. Where the change is from a Group S or Group U occupancy and there is no change of risk category, compliance with Section 304.3.2 shall be permitted.

    [BS] 1006.4 Access to Risk Category IV. Any structure that provides operational access to an adjacent structure assigned to Risk Category IV as the result of a change of occupancy shall itself comply with Sections 1608 and 1609 of the California Building Code and Section 304.3.1 of this code. Where operational access to Risk Category IV is less than 10 feet (3048 mm) from either an interior lot line or from another structure, access protection from potential falling debris shall be provided.

    SECTION 1007—ELECTRICAL

    1007.1 Special occupancies. Where the occupancy of an existing building or part of an existing building is changed to one of the following special occupancies as described in the California Electrical Code, the electrical wiring and equipment of the building or portion thereof that contains the proposed occupancy shall comply with the applicable requirements of the California Electrical Code :

    1. Hazardous locations.

    2. Commercial garages, repair and storage.

    3. Aircraft hangars.

    4. Gasoline dispensing and service stations.

    5. Bulk storage plants.

    6. Spray application, dipping and coating processes.

    7. Reserved.

    8. Places of assembly.

    9. Theaters, audience areas of motion picture and television studios, and similar locations.

    10. Motion picture and television studios and similar locations.

    11. Motion picture projectors.

    12. Agricultural buildings.

    1007.2 Unsafe conditions. Where the occupancy of an existing building or part of an existing building is changed, all unsafe conditions shall be corrected without requiring that all parts of the electrical system comply with the California Electrical Code .

    1007.3 Service upgrade. Where the occupancy of an existing building or part of an existing building is changed, electrical service shall be upgraded to meet the requirements of the California Electrical Code for the new occupancy.

  • CBC § 422.3 High 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:

    1. 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.
    2. 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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    PRESCRIPTIVE COMPLIANCE METHOD

    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.

  • CBC § 506.5.1 High relevance — show source text

    [BS] 506.5.1 Live loads. Structural elements carrying tributary live loads from an area with a change of occupancy shall satisfy the requirements of Section 1607 of the California Building Code . Design live loads for areas of new occupancy shall be based on Section 1607 of the California Building Code . Design live loads for other areas shall be permitted to use previously approved design live loads.

    Exception: Structural elements whose demand-capacity ratio considering the change of occupancy is not more than 5 percent greater than the demand-capacity ratio based on previously approved live loads need not comply with this section.

    [BS] 506.5.2 Snow and wind loads. Where a change of occupancy results in a structure being assigned to a higher risk category, the structure shall satisfy the requirements of Sections 1608 and 1609 of the California Building Code for the new risk category.

    Exception: Where the area of the new occupancy is less than 10 percent of the building area, compliance with this section is not required. The cumulative effect of occupancy changes over time shall be considered.

    [BS] 506.5.3 Seismic loads (seismic force-resisting system). Where a change of occupancy results in a building being assigned to a higher risk category, or where the change is from a Group S or Group U occupancy to any occupancy other than Group S or

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    Group U, the lateral force-resisting system of the building shall comply with Section 304.3.1 for the new risk category. Where a change of occupancy results in a building being assigned to Risk Category IV and Seismic Design Category D or F, nonstructural components serving any portion of the building changed to Risk Category IV shall comply with the requirements of Section 1613 of the California Building Code or shall comply with ASCE 41 using an objective of Operational nonstructural performance with the BSE-1N earthquake hazard level.

    Exceptions:

    1. Where the area of the new occupancy is less than 10 percent of the building area, the occupancy is not changing from a Group S or Group U occupancy, and the new occupancy is not assigned to Risk Category IV, compliance with this section is not required. The cumulative effect of occupancy changes over time shall be considered.
    2. Where a change of use results in a building being reclassified from Risk Category I or II to Risk Category III and the seismic coefficient, S DS, is less than 0.33, compliance with this section is not required.
    3. Unreinforced masonry bearing wall buildings assigned to Risk Category III and to Seismic Design Category A or B, shall be permitted to use Appendix Chapter A1 of this code.
    4. Where the change is from a Group S or Group U occupancy and there is no change of risk category, compliance with Section 304.3.2 shall be permitted.

    [BS] 506.5.4 Access to Risk Category IV. Any structure that provides operational access to an adjacent structure assigned to Risk Category IV as the result of a change of occupancy shall itself comply with Sections 1608 and 1609 of the California Building Code and Section 304.3.1 of this code. Where operational access to the Risk Category IV structure is less than 10 feet (3048 mm) from either an interior lot line or from another structure, access protection from potential falling debris shall be provided.

  • CBC § 1001.2.1 High relevance — show source text

    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

    1004.1 General. Fire protection requirements in Section 1011 shall apply where either of the following occur:

    1. A building or portion thereof undergoes a change of occupancy.
    2. A building or portion thereof undergoes a change of occupancy and there is a different fire protection system threshold requirement in Chapter 9 of the current California Building Code than exists in the current building or portion thereof.

    SECTION 1005—MEANS OF EGRESS

    1005.1 General. Means of egress in portions of buildings undergoing a change of occupancy classification shall comply with Section 1011.

    SECTION 1006—STRUCTURAL

    [BS] 1006.1 Live loads. Structural elements carrying tributary live loads from an area with a change of occupancy shall satisfy the requirements of Section 1607 of the California Building Code . Design live loads for areas of new occupancy shall be based on Section 1607 of the California Building Code . Design live loads for other areas shall be permitted to use previously approved design live loads.

    Exception: Structural elements whose demand-capacity ratio considering the change of occupancy is not more than 5 percent greater than the demand-capacity ratio based on previously approved live loads.

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    �

    CHANGE OF OCCUPANCY

    [BS] 1006.2 Snow and wind loads. Where a change of occupancy results in a structure being assigned to a higher risk category, the structure shall satisfy the requirements of Sections 1608 and 1609 of the California Building Code for the new risk category.

  • CBC § 2.1 High relevance — show source text

    SECTION 302 A —GENERAL PROVISIONS

    302 A .1 Dangerous conditions. The code official shall have the authority to require the elimination of conditions deemed dangerous.

    302 A .2 Additional codes. Alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and struc- tures shall comply with the provisions for alterations, repairs, additions and changes of occupancy or relocation, respectively, in the California Fire Code, California Mechanical Code, California Plumbing Code and California Electrical Code. Where provisions of the other codes conflict with provisions of this chapter, the provisions of this chapter shall take precedence.

    302 A .2.1 Additional codes in health care. In existing Group I-2 occupancies, ambulatory health care facilities, outpatient clinics and hyperbaric facilities, alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and structures shall also comply with NFPA 99.

    302 A .3 Existing materials and equipment. Materials and equipment already in use in a building in compliance with requirements or approvals in effect at the time of their erection or installation shall be permitted to remain in use unless determined by the code official to be unsafe in accordance with California Building Code Section 116.

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    PROVISIONS FOR ALL COMPLIANCE METHODS

    302A.3.1 Existing seismic force-resisting systems. Where the existing seismic force-resisting system is a type that can be designated ordinary or is a welded steel moment frame constructed under a permit issued prior to October 25, 1994, values of R, W0 and Cd for the existing seismic force-resisting system shall be those specified by the California Building Code for an ordinary system unless it is demonstrated that the existing system will provide performance equivalent to that of a detailed, intermediate or special system.

    302 A .4 New and replacement materials. Except as otherwise required or permitted by this code, materials and equipment permitted by the applicable code for new construction shall be used. Like materials shall be permitted for repairs and alterations, provided no hazard to life, health or property is c reated. Hazardous materials shall not be used where the code for new construction would not permit their use in buildings of similar occupancy, purpose and location.

    302 A .4.1 New structural members and connections. New structural members and connections shall comply with the detailing provisions of the California Building Code for new buildings of similar structure, purpose and location.

    Exception: Where alternative design criteria are specifically permitted.

    302 A .5 Occupancy and use. Where determining the appropriate application of the referenced sections of this code, the occupancy and use of a building shall be determined in accordance with Chapter 3 of the California Building Code .

  • CBC § 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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    13 PERFORMANCE COMPLIANCE METHODS

    Not adopted by the State of California (May be available for adoption by local ordinance. See Section 1.1.11.) (See Section 104.11 for consideration of alternative means of compliance.)

    User notes:

    About this chapter: Chapter 13 allows for existing buildings to be evaluated so as to show that alterations, while not meeting new construction requirements, will improve the current existing situation. Provisions are based on a numerical scoring system involving 21 various safety parameters and the degree of code compliance for each issue.

    SECTION 1301—GENERAL

    1301.1 Scope. The provisions of this chapter shall apply to the alteration, addition and change of occupancy of existing structures, including historic structures, as referenced in Section 301.3.3. The provisions of this chapter are intended to maintain or increase the current degree of public safety, health and general welfare in existing buildings while permitting, alteration, addition and change of occupancy without requiring full compliance with Chapters 6 through 12, except where compliance with the prescriptive method of Chapter 5 or the work area method of other provisions of this code is specifically required in this chapter.

    1301.1.1 Compliance with other methods. Alterations, additions and changes of occupancy to existing structures shall comply with the provisions of this chapter or with one of the methods provided in Section 301.3.

    SECTION 1302—APPLICABILITY

    1302.1 General. Existing buildings in which there is work involving additions, alterations or changes of occupancy shall be made to conform to the requirements of this chapter or the provisions of Chapters 6 through 12. The provisions of Sections 1302.1.1 through 1302.1.6 shall apply to existing occupancies that will continue to be, or are proposed to be, in Groups A, B, E, F, I-2, M, R and S. These provisions shall also apply to Group U occupancies where such occupancies are undergoing a change of occupancy or a partial change in occupancy with separations in accordance with Section 1302.1.2. These provisions shall not apply to buildings with occupancies in Group H, I-1, I-3 or I-4.

    1302.1.1 Change in occupancy. Where an existing building is changed to a new occupancy classification and this section is applicable, the provisions of this section for the new occupancy shall be used to determine compliance with this code.

    1302.1.2 Partial change in occupancy. Where a portion of the building is changed to a new occupancy classification and that portion is separated from the remainder of the building with fire barrier or horizontal assemblies having a fire-resistance rating as required by Table 508.4 of the International Building Code or Section R302 of the International Residential Code for the separate occupancies, or with approved compliance alternatives, the portion changed shall be made to conform to the provisions of this section. Only the portion separated shall be required to be evaluated for compliance.

  • CBC § 1004.1 High relevance — show source text

    SECTION 1004—FIRE PROTECTION

    1004.1 General. Fire protection requirements in Section 1011 shall apply where either of the following occur:

    1. A building or portion thereof undergoes a change of occupancy.
    2. A building or portion thereof undergoes a change of occupancy and there is a different fire protection system threshold requirement in Chapter 9 of the current California Building Code than exists in the current building or portion thereof.

    SECTION 1005—MEANS OF EGRESS

    1005.1 General. Means of egress in portions of buildings undergoing a change of occupancy classification shall comply with Section 1011.

    SECTION 1006—STRUCTURAL

    [BS] 1006.1 Live loads. Structural elements carrying tributary live loads from an area with a change of occupancy shall satisfy the requirements of Section 1607 of the California Building Code . Design live loads for areas of new occupancy shall be based on Section 1607 of the California Building Code . Design live loads for other areas shall be permitted to use previously approved design live loads.

    Exception: Structural elements whose demand-capacity ratio considering the change of occupancy is not more than 5 percent greater than the demand-capacity ratio based on previously approved live loads.

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    �

    CHANGE OF OCCUPANCY

    [BS] 1006.2 Snow and wind loads. Where a change of occupancy results in a structure being assigned to a higher risk category, the structure shall satisfy the requirements of Sections 1608 and 1609 of the California Building Code for the new risk category.

    Exception: Where the area of the new occupancy is less than 10 percent of the building area. The cumulative effect of occupancy changes over time shall be considered.

    [BS] 1006.3 Seismic loads. Where a change of occupancy results in a building being assigned to a higher risk category, or where the change is from a Group S or Group U occupancy to any occupancy other than Group S or Group U, the lateral force-resisting system of the building shall comply with Section 304.3.1 for the new risk category. Where a change of occupancy results in a building being assigned to Risk Category IV and Seismic Design Category D or F, nonstructural components serving any portion of the building changed to Risk Category IV shall comply with the requirements of Section 1613 of the California Building Code or shall comply with ASCE 41 using an objective of operational nonstructural performance with the BSE-1N earthquake hazard level.

    Exceptions:

    1. Where a change of use results in a building being reclassified from Risk Category I or II to Risk Category III and the seismic coefficient, S DS, is less than 0.33, compliance with this section is not required.

    2. Where the area of the new occupancy is less than 10 percent of the building area, the occupancy is not changing from a Group S or Group U occupancy, and the new occupancy is not assigned to Risk Category IV, compliance with this section is not required. The cumulative effect of occupancy changes over time shall be considered.

    3. Reserved.

    4. Where the change is from a Group S or Group U occupancy and there is no change of risk category, compliance with Section 304.3.2 shall be permitted.

  • CBC § 1.10.1 High relevance — show source text

    **_ 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). Functional service spaces shall comply with the requirements in the California Building Code, Sections 1224, 1225, 1226, 1227 and 1228.

    301.1.1 Bleachers, folding and telescopic seating and grandstands. Existing bleachers, folding and telescopic seating and grandstands shall comply with ICC 300.

    301.2 Repairs. Repairs shall comply with the requirements of Chapter 4.

    301.3 Alteration, addition or change of occupancy. The alteration, addition or change of occupancy of all existing buildings shall comply with one of the methods listed in Section 301.3.1, 301.3.2 or 301.3.3 as selected by the applicant. Sections 301.3.1 through 301.3.3 shall not be applied in combination with each other. [OSHPD 1R, 2, 4 and 5] Sections 301.3.2 and 301.3.3, not adopted by OSHPD.

    Exception: Subject to the approval of the code official, 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

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    PROVISIONS FOR ALL COMPLIANCE METHODS

    members added as part of the alteration shall comply with the California Building Code . This exception shall not apply to the following:

    1. Alterations for accessibility required by the California Building Code, Chapter 11A.

    2. Alterations that constitute substantial improvement in flood hazard areas, which shall comply with Sections 503.2, 701.3 or 1303.1.3.

    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.

  • CBC § 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.

  • CBC § 1001.1 High 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 § 1009.3 High relevance — show source text

    1009.3 Interceptor required. If the new occupancy will produce grease or oil-laden wastes, interceptors shall be provided as required in the California Plumbing Code .

    1009.4 Chemical wastes. If the new occupancy will produce chemical wastes, the following shall apply:

    1. If the existing piping is not compatible with the chemical waste, the waste shall be neutralized prior to entering the drainage system or the piping shall be changed to a compatible material.
    2. Chemical waste shall not discharge to a public sewer system without the approval of the sewage authority.

    SECTION 1010—OTHER REQUIREMENTS

    1010.1 Light and ventilation. Light and ventilation shall comply with the requirements of the California Building Code for the new

    occupancy.

    SECTION 1011—CHANGE OF OCCUPANCY CLASSIFICATION

    1011.1 General. The provisions of this section shall apply to buildings or portions thereof undergoing a change of occupancy classification. This includes a change of occupancy classification within a group as well as a change of occupancy classification from one group to a different group. The provisions of this section shall also apply where there is a change of occupancy within a building or portion thereof and there is a different fire protection system threshold requirement in Chapter 9 of the current California Building Code than exists in the current building or space. Such buildings shall also comply with Sections 1002 through 1010 of this code.

    1011.2 Fire protection systems. Fire protection systems shall be provided in accordance with Sections 1011.2.1 and 1011.2.2.

    1011.2.1 Automatic sprinkler system. The installation of an automatic sprinkler system shall be required where there is a change of occupancy classification and Chapter 9 of the current California Building Code requires an automatic sprinkler system based on the new occupancy or where there is a change of occupancy within the space where there is a different fire protection system threshold requirement in Chapter 9 of the current California Building Code than exists in the current building or space . The installation of the automatic sprinkler system shall be required within the area of the change of occupancy and areas of the building not separated by a fire wall from the change of occupancy.

    1011.2.1.1 Nonrequired automatic sprinkler systems. The code official is authorized to permit the removal of an existing automatic sprinkler system where all of the following conditions exist:

    1. The system is not required for new construction.
    2. Portions of the system that are exposed to the public are removed.
    3. The system was not installed as part of any special construction features, including fire-resistance-rated assemblies and smoke-resistive assemblies, conditions of occupancy, means of egress conditions, fire code deficiencies, approved modifications or approved alternative materials, design and methods of construction, and equipment applying to the building.

    1011.2.1.1.1 Approval. Plans, investigation and evaluation reports, and other data shall be submitted documenting compliance with Section 1011.2.1.1 for review and approval in support of a determination authorizing the removal of the automatic sprinkler system by the code official.

    1011.2.2 Fire alarm and detection system. Where a change in occupancy classification occurs or where there is a change of occupancy within a space where there is a different fire protection system threshold requirement in Chapter 9 of the current Cali- fornia Building Code than exists in the current building or space that requires a fire alarm and detection system to be provided based on the new occupancy, such system shall be in accordance with Chapter 11 and Section 907 of the California Fire Code.

Frequently asked questions

Do I always need a permit and a new certificate of occupancy when I change uses?

Yes — any change in use must follow the applicable code requirements and, if the occupancy classification changes, a certificate of occupancy must be issued once the new requirements are met (§ 1001.2.1; § 1001.3) .

If I only change 8% of the building, can I ignore structural and seismic requirements?

Not automatically. The code provides some exceptions where the new occupancy area is less than 10%, but cumulative past changes and other exceptions are considered; some triggers still apply in specific circumstances. Always confirm against the specific sections and exceptions (§ 1006.2–1006.3) .

What if the change is only a different function but within the same occupancy group?

A “change in function” still must meet functional requirements for the work classified in Chapter 6 and Sections 1002–1010; some work may be limited to the space altered but functional code requirements for that use apply (§ 1001.2.1) .

Can I remove an existing sprinkler system when I change occupancy?

Removal is possible only if the sprinkler system is not required for new construction, affected public areas are removed, and the system was not installed for special conditions; removal requires documentation and code‑official approval (§ 1011.2.1.1) .

If my new use produces grease or chemical wastes, what do I need to do?

Grease/oil wastes require interceptors per the California Plumbing Code; chemical wastes may require neutralization or piping changes and approval before discharging to public sewers (§ 1009.3–1009.4) .

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