CEBC · California Existing Building Code

Which portion of a building must comply when only part changes occupancy?

If only part of a building changes occupancy, CEBC **§ 1302.1.2** says that if that part is separated from the rest by the required fire‑resistance rated barrier or horizontal assembly (or an approved alternative), only the separated portion must comply; if not, the code provisions for each occupancy apply to the entire building and the stricter requirements govern.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

The California Existing Building Code (CEBC) says that when only a portion of a building changes occupancy, whether only that portion must be brought into compliance depends on whether it is physically separated. If the portion is separated from the rest of the building by a fire barrier or horizontal assembly with the fire‑resistance rating required for the separate occupancies (per Table 508.4 of the IBC or Section R302 of the IRC), then only the separated portion must be evaluated and made to conform to the applicable provisions. If it is not separated by those rated assemblies (or approved alternatives), then the provisions for each occupancy apply to the entire building and the stricter requirements apply where the provisions conflict (see § 1302.1.2).

Single most important rule: If the area being changed is fully separated from the rest of the building by rated fire barriers/horizontal assemblies (or approved alternatives), only that separated area must comply; otherwise the whole building must be evaluated and brought into compliance.

Requirements in detail

Basic decision rule (plain steps)

  • Determine whether the portion being changed is physically separated from the remainder of the building by a fire barrier or horizontal assembly having the fire‑resistance rating required for the two occupancies. § 1302.1.2 controls this determination.
  • If the separation meets the required rating (or an approved compliance alternative), then only the separated portion must be made to conform to the CEBC requirements for the new occupancy.
  • If the separation does not meet the required rating (or no approved alternative is used), then the provisions that apply to each occupancy extend to the entire building. Where two provisions conflict, apply the one that provides greater public safety.

Decision table — key dimensions and code reference

Decision factor Values/thresholds to check Code reference
Is the changed area separated from the remainder of the building? Yes / No — separation must be by a fire barrier or horizontal assembly with required FRR (or approved alternative). § 1302.1.2
Required rating source Use Table 508.4 (IBC) or Section R302 (IRC) for the fire‑resistance rating for the separating assemblies. (CEBC references these documents.) § 1302.1.2
Scope of compliance if separated Only the separated portion must be evaluated and made to conform to this chapter. § 1302.1.2
Scope of compliance if not separated The provisions applicable to each occupancy apply to the entire building; conflicting provisions — apply requirements that secure the greater public safety. § 1302.1.2
Use of alternatives Approved compliance alternatives are permitted in lieu of the specific rated assemblies; approval is required from the code official. § 1302.1.2

Note: The CEBC text references Table 508.4 of the IBC and Section R302 of the IRC for the numeric fire‑resistance ratings. The actual numeric ratings and assembly details are in those referenced codes; those tables are not reproduced in the retrieved CEBC excerpt.

How separation is typically interpreted

  • A fire barrier is an assembly that limits fire spread between occupancies; a horizontal assembly separates occupancies vertically (floor/ceiling). The CEBC requires their fire‑resistance rating to match the rating that would be required for separations between those occupancies under the referenced IBC/IRC provisions. § 1302.1.2 sets the separation‑based rule.
  • Approved compliance alternatives can be used instead of the exact rated assembly if the code official accepts them; the CEBC allows this option. § 1302.1.2.

Exceptions & special cases

  • Approved alternatives: The CEBC explicitly permits approved compliance alternatives to the fire‑rated assemblies; if accepted by the authority having jurisdiction, those alternatives can limit the scope to the separated portion. § 1302.1.2.
  • No separation = whole building: Where there is no rated separation (and no approved alternative), the CEBC requires that the provisions applying to each occupancy apply to the entire building, with the stricter rules prevailing where they conflict. § 1302.1.2.
  • Interaction with change‑of‑occupancy provisions elsewhere: The CEBC’s Chapter 13 applicability language and the Change‑of‑Occupancy rules (Chapter 5/Section 506 and related structural, egress, fire protection, and systems requirements) can impose additional requirements — for example, structural or seismic upgrades driven by a change of occupancy (see § 506 series and the CEBC structural sections). Those may include area‑based exceptions (e.g., some structural/seismic requirements are not required if the new occupancy area is less than 10 percent of building area — see § 506.5 exceptions). These related rules must be checked in parallel.

If you need the specific numeric fire‑resistance ratings for a required fire barrier or horizontal assembly, consult Table 508.4 of the IBC or Section R302 of the IRC (not contained in the CEBC excerpt). The CEBC references those tables but does not reproduce their numeric values in the retrieved text.

Common mistakes

  • Assuming any partition satisfies the separation requirement. The CEBC requires fire barriers or horizontal assemblies with the fire‑resistance rating specified by Table 508.4 (IBC) or Section R302 (IRC) — a simple gypsum partition is often insufficient. § 1302.1.2.
  • Forgetting that if the area is not separated, the entire building may be pulled into compliance — and the stricter of conflicting requirements controls. § 1302.1.2.
  • Overlooking other code obligations triggered by a change of occupancy (structural live loads, seismic category changes, means of egress, fire protection, electrical/mechanical/plumbing upgrades) that may apply even if only a portion changes. See CEBC change‑of‑occupancy provisions (e.g., § 506 and the applicable structural/egress sections).
  • Assuming sprinklers or other fire‑protection systems automatically negate the need for rated separations — the CEBC allows alternatives only with approval; do not assume automatic credit without approval. § 1302.1.2.

Worked example — concrete scenario

Scenario: Existing two‑story commercial building, total floor area = 10,000 ft². The owner proposes to convert a 2,000 ft² ground‑floor tenant space from retail (Group M) to an office use (Group B). No walls are currently rated.

  1. Evaluate separation:

    • If the tenant space is closed off from the rest of the building by a continuous fire barrier and any required horizontal assemblies constructed to the fire‑resistance rating specified for M/B separations in Table 508.4 (IBC) or Section R302 (IRC) (or the owner gets an approved compliance alternative), then only the 2,000 ft² changed portion must be made to conform to the CEBC requirements for the new occupancy. § 1302.1.2.
    • If the tenant space is not separated by the required rated assemblies (no rated partition and no approved alternative), then the CEBC requires that the provisions that apply to each occupancy apply to the entire 10,000 ft² building. Where the M and B rules conflict, apply the requirements that provide greater public safety. § 1302.1.2.

  2. Check related triggers:

    • If the change raises the building’s risk category or changes design live loads, structural or seismic upgrades in § 506 (and CEBC structural sections) can apply — note CEBC exceptions where the new occupancy area is less than 10% of building area may limit some requirements (2,000 ft² is 20% in this example, so some exceptions would not apply). See § 506.5 and associated exceptions.

Outcome summary: With proper rated separation (or approved alternative) only the 2,000 ft² tenant space needs CEBC compliance for its new occupancy; without it, plan for potentially upgrading systems and features for the entire 10,000 ft² building. § 1302.1.2.

Related provisions (CEBC sections to review)

  • § 1302.1.2 — Partial change in occupancy (primary controlling rule).
  • § 1302.1.1 — Change in occupancy (general rule for a full‑building change).
  • § 1302.1.3 — Additions (how additions are treated when occupancy changes).
  • § 506.1 / § 506 — Change of occupancy: general compliance and certificate of occupancy rules.
  • § 506.5 — Structural requirements triggered by change of occupancy (including the 10 percent area exception).
  • § 1004.1 — Fire protection requirements when a building or portion undergoes a change of occupancy.
  • § 1006.3 — Seismic load requirements when a change of occupancy affects risk category (see exceptions).
  • § 1007.1 — Electrical systems requirements for special occupancies when occupancy changes.

If you want, I can:

  • Pull the exact CEBC text for any of the related sections listed above; or
  • Draft a checklist you can use during plan review to determine whether the changed portion is sufficiently separated and which other CEBC sections to trigger on.

Code references

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

  • CEBC § 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).

  • CEBC § 1011.5.6. High relevance — show source text
    1. The replacement window is the manufacturer’s largest standard size window that will fit within the existing frame or existing rough opening. The replacement window shall be permitted to be of the same operating style as the existing window or a style that provides for an equal or greater window opening area than the existing window.
    2. Where the replacement of the window is part of a change of occupancy, it shall comply with Section 1011.5.6.

    505.3.1 Control devices. Window opening control devices or fall prevention devices complying with ASTM F2090 shall be permitted for use on windows required to provide emergency escape and rescue openings. After operation to release the control device allowing the window to fully open, the control device shall not reduce the net clear opening area of the window unit. Emergency escape and rescue openings shall be operational from the inside of the room without the use of keys or tools.

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    PRESCRIPTIVE COMPLIANCE METHOD

    505.4 Bars, grilles, covers or screens. Bars, grilles, covers, screens or similar devices are permitted to be placed over emergency escape and rescue openings, bulkhead enclosure or window wells that serve such openings, provided all of the following conditions are met:

    1. The minimum net clear opening size complies with the code that was in effect at the time of construction.
    2. Such devices shall be releasable or removable from the inside without the use of a key, tool or force greater than that which is required for normal operation of the escape and rescue opening.
    3. Where such devices are installed, they shall not reduce the net clear opening of the emergency escape and rescue openings .
    4. Smoke alarms shall be installed in accordance with Section 907.2.11 of the California Building Code .

    SECTION 506—CHANGE OF OCCUPANCY

    506.1 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 code 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 of the California Building Code unless required by Section 506.5.

    506.1.1 Change in the character of use. A change of occupancy with no change of occupancy classification shall not be made to any structure that will subject the structure to any special provisions of the applicable California Codes, without approval of the code official. Compliance shall be only as necessary to meet the specific provisions and is not intended to require the entire building be brought into compliance.

    506.1.2 Change in function. [OSHPD 1R, 2, 4 and 5] A change in function shall require compliance with all the functional require- ments for new construction in the California Building Code, including requirements in Sections 1224, 1225, 1226, 1227 and 1228.

  • CEBC § 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.

  • CEBC § 1.1 High relevance — show source text

    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.

    506 A .4 Existing emergency escape and rescue openings. Where a change of occupancy would require an emergency escape and rescue opening in accordance with Section 1031.1 of the California Building Code, operable windows serving as the emergency escape and rescue opening shall comply with the following:

    1. An existing operable window shall provide a minimum net clear opening of 4 square feet (0.38 m [2] ) with a minimum net clear opening height of 22 inches (559 mm) and a minimum net clear opening width of 20 inches (508 mm).
    2. A replacement window where such window complies with both of the following: 2.1. The replacement window meets the size requirements in Item 1. 2.2. The replacement window is the manufacturer’s largest standard size window that will fit within the existing frame or existing rough opening. The replacement window shall be permitted to be of the same operating style as the existing window or a style that provides for an equal or greater window opening area than the existing window.

    506 A .5 Structural. Any building undergoing a change of occupancy shall satisfy the requirements of this section.

    506 A .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 A of the California Building Code . Design live loads for areas of new occupancy shall be based on Section 1607 A 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.

    506 A .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 A and 1609 A 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.

  • CEBC § 506.1 High relevance — show source text

    SECTION 506—CHANGE OF OCCUPANCY

    506.1 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 code 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 of the California Building Code unless required by Section 506.5.

    506.1.1 Change in the character of use. A change of occupancy with no change of occupancy classification shall not be made to any structure that will subject the structure to any special provisions of the applicable California Codes, without approval of the code official. Compliance shall be only as necessary to meet the specific provisions and is not intended to require the entire building be brought into compliance.

    506.1.2 Change in function. [OSHPD 1R, 2, 4 and 5] A change in function shall require compliance with all the functional require- ments for new construction in the California Building Code, including requirements in Sections 1224, 1225, 1226, 1227 and 1228.

    Exception [OSHPD 1R] : Hospital buildings removed from acute care service adapted for re-use as skilled nursing facilities, acute psychiatric hospitals or out-patient services of a hospital may be permitted to meet the minimum room clearances, areas and dimensions of the 2001 California Building Code for existing rooms re-used for a similar purpose, subject to the approval of OSHPD.

    506.2 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.

    506.3 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.

    506.4 Existing emergency escape and rescue openings. Where a change of occupancy would require an emergency escape and rescue opening in accordance with Section 1031.1 of the California Building Code, operable windows serving as the emergency escape and rescue opening shall comply with the following:

    1. An existing operable window shall provide a minimum net clear opening of 4 square feet (0.38 m [2] ) with a minimum net clear opening height of 22 inches (559 mm) and a minimum net clear opening width of 20 inches (508 mm).
    2. A replacement window where such window complies with both of the following: 2.1. The replacement window meets the size requirements in Item 1. 2.2. The replacement window is the manufacturer’s largest standard size window that will fit within the existing frame or existing rough opening. The replacement window shall be permitted to be of the same operating style as the existing window or a style that provides for an equal or greater window opening area than the existing window.

    [BS] 506.5 Structural. Any building undergoing a change of occupancy shall satisfy the requirements of this section.

  • CEBC § 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.

  • CEBC § 1.11. High relevance — show source text

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

    2025 CALIFORNIA EXISTING BUILDING CODE 13-1

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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.

  • CEBC § 1.1 High relevance — show source text

    California Energy Commission, State Fire Marshal and DSA-AC requirements for existing structures shall be enforced by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).

    301 A .1.1 Bleachers, grandstands and folding and telescopic seating. Existing bleachers, grandstands and folding and telescopic seating shall comply with ICC 300.

    301 A .2 Repairs. Repairs shall comply with the requirements of Chapter 4 A .

    301 A .3 Alteration, addition or change of occupancy. The alteration, addition or change of occupancy of all existing buildings or structures shall comply with one of the methods or categories listed in Section 301 A .3.1, 301 A .3.2 or 301 A .3.3. Section 304A.3.2 applies to all methods or categories. Sections 301 A .3.1 through 301 A .3.3 shall not be applied in combination with each other , except when permitted by the enforcement agency.

    Exception: Subject to the approval of the enforcement agency, alterations complying with the laws in existence at the time the building or the affected portion of the building was built shall be considered in compliance with the provisions of this code. New structural members added as part of the alteration shall comply with the California Building Code .

    301 A .3.1 Prescriptive compliance method. Alterations, additions and changes of occupancy complying with Chapter 5 A of this code for existing buildings or structures shall be considered in compliance with the provisions of this code.

    301 A .3.2 Nonconforming buildings . Alterations, additions and changes of occupancy to existing buildings or structures designed in accordance with the Pre-1973 building code complying with Section 304A.3.1 and the applicable requirements herein shall be considered in compliance with the provisions of this code.

    301 A .3.3 Performance- based method. Alterations, additions and changes of occupancy to existing buildings or structures complying with Sections 304A.3.4 and 304A.3.5 of this code shall be considered in compliance with the provisions of this code.

    301 A .4 Moved structures . Structures moved into or within the jurisdiction shall comply with the provisions of the California Building Code for new structures.

    301A.5 Reserved.

    301A.6 Peer review requirements. Peer review requirements shall comply with California Building Code Section 1617A.1.41.

    301A.7 Earthquake monitoring instruments for existing buildings. Earthquake monitoring instrumentation of existing buildings shall comply with Section 313A.

    301A.8 Compliance alternatives for services/systems and utilities . Compliance alternatives for services/systems and utilities shall comply with Section 310A.

    301A.9 Compliance alternatives for means of egress. Means of egress through existing buildings shall comply with Section 311A.

    301A.10 Removal of hospital buildings from general acute care services. Removal of hospital buildings from General Acute Care Services shall comply with Section 312A.

  • CEBC § 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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    PRESCRIPTIVE COMPLIANCE METHOD

    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.

  • CEBC § 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.

  • CEBC § 1.6.2 High relevance — show source text

    R109.1.6.2 Operation and maintenance manual. At the time of final inspection, a manual, compact disc, web-based reference or other media acceptable to the enforcing agency shall be placed in the building in accordance with the California Green Building Standards Code, Chapter 4, Division 4.4.

    R109.2 Inspection agencies. The building official is authorized to accept reports of approved agencies, provided such agencies satisfy the requirements as to qualifications and reliability.

    R109.3 Inspection requests. It shall be the duty of the permit holder or their agent to notify the building official that such work is ready for inspection. It shall be the duty of the person requesting any inspections required by this code to provide access to and means for inspection of such work.

    R109.4 Approval required. Work shall not be done beyond the point indicated in each successive inspection without first obtaining the approval of the building official. The building official, upon notification, shall make the requested inspections and shall either indicate the portion of the construction that is satisfactory as completed, or shall notify the permit holder or an agent of the permit

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    DIVISION II SCOPE AND ADMINISTRATION

    holder wherein the same fails to comply with this code. Any portions that do not comply shall be corrected and such portion shall not be covered or concealed until authorized by the building official.

    SECTION R110—CERTIFICATE OF OCCUPANCY

    R110.1 Use and change of occupancy. A building or structure shall not be used or occupied in whole or in part, and a change of occupancy of a building or structure or portion thereof shall not be made, until the building official has issued a certificate of occupancy therefor as provided herein. Issuance of a certificate of occupancy shall not be construed as an approval of a violation of the provisions of this code or of other ordinances of the jurisdiction. Certificates presuming to give authority to violate or cancel the provisions of this code or other ordinances of the jurisdiction shall not be valid.

    Exceptions:

    1. Certificates of occupancy are not required for work exempt from permits under Section R105.2.
    2. Accessory buildings or structures.

    R110.2 Certificate issued. After the building official inspects the building or structure and does not find violations of the provisions of this code or other laws that are enforced by the department, the building official shall issue a certificate of occupancy containing the following:

    1. The permit number.

    2. The address of the structure.

    3. The name and address of the owner or the owner’s authorized agent.

    4. A description of that portion of the structure for which the certificate is issued.

    5. A statement that the described portion of the structure has been inspected for compliance with the requirements of this code.

    6. The name of the building official.

    7. The edition of the code under which the permit was issued.

    8. Where an automatic sprinkler system is provided and whether the sprinkler system is required.

    9. Any special stipulations and conditions of the building permit.

    R110.3 Temporary occupancy. The building official is authorized to issue a temporary certificate of occupancy before the completion of the entire work covered by the permit, provided that such portion or portions shall be occupied safely. The building official shall set a time period during which the temporary certificate of occupancy is valid.

  • CEBC § 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.

Frequently asked questions

When does the CEBC treat only the changed area rather than the whole building?

Only when the changed area is separated from the remainder of the building by a fire barrier or horizontal assembly having the fire‑resistance rating required for the separate occupancies (or by an approved compliance alternative). § 1302.1.2.

Who decides whether an alternative separation is acceptable?

The code official (authority having jurisdiction) must approve any compliance alternative used in place of the specific rated assemblies referenced by the CEBC. § 1302.1.2.

If the portion is not separated, which rules apply to the whole building?

If not separated, the CEBC says the provisions applying to each occupancy apply to the entire building; where provisions conflict, apply those that secure the greater public safety. § 1302.1.2.

Does adding sprinklers mean I don’t need rated separation?

Not automatically. The CEBC allows approved compliance alternatives, but sprinklers alone do not replace the separation requirement unless the authority having jurisdiction accepts an alternative approach. § 1302.1.2.

How does the 10% area exception affect partial changes?

Other CEBC sections (for example structural and seismic provisions in § 506.5 and related sections) include area‑based exceptions where some upgrades aren’t required if the new occupancy area is less than 10 percent of building area; those exceptions are separate from the separation rule in § 1302.1.2 and must be checked.

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