CEBC · California Existing Building Code
When can a partial change of occupancy be limited to the separated portion?
If you change only part of a building’s occupancy, California Existing Building Code § 1302.1.2 lets you limit required upgrades to that portion — but only if it’s separated from the rest of the building by a fire barrier or horizontal assembly that meets the required fire‑resistance rating. If no rated separation exists (or is inadequate), the entire building must be evaluated and brought into compliance; sprinkler and egress rules in § 1011 may still add requirements for the changed area or adjacent spaces.
Last reviewed: July 6, 2026
What the code requires — in plain English
When only part of a building is being reclassified, the change may be evaluated and enforced only for that portion if that portion is physically separated from the remainder of the building with fire barriers or horizontal assemblies having the fire‑resistance rating required for the occupancies being separated. If that separation is provided and meets the required rating (or an approved alternative), only the separated portion must be made to conform to the change‑of‑occupancy provisions. See § 1302.1.2 for this rule.
Also remember that the general change‑of‑occupancy provisions in § 1011.1 apply to buildings or portions undergoing a change of occupancy classification, and they carry separate requirements for fire protection and means of egress that may affect whether the partial‑only approach is allowed (for example, sprinkler and alarm requirements).
If the new occupancy area is separated by fire barriers or horizontal assemblies meeting the required fire‑resistance rating, you only have to evaluate and upgrade the separated portion. If that separation does not exist, the entire building must be evaluated and brought into compliance as needed.
Requirements in detail
Key defined terms (first mention)
- Separated — physically divided from the rest of the building by fire barrier or horizontal assembly with the required fire‑resistance rating per the referenced codes (IBC Table 508.4 or IRC R302). § 1302.1.2.
- Change of occupancy classification — any change that results in a different occupancy classification (within a group or between groups); the rules in § 1011.1 govern such changes.
What the decision depends on — short decision table
| Decision dimension | Values / threshold | Effect on scope of compliance | Code Reference |
|---|---|---|---|
| Is the changed portion separated by required assemblies? | Yes / No | Yes → only separated portion must be evaluated. No → entire building must be evaluated. | § 1302.1.2 |
| What assembly rating is needed? | Rating as required by IBC Table 508.4 or IRC R302 (or approved alternative) | Separation must meet that rating to qualify. | § 1302.1.2 (references IBC/IRC tables) |
| Does the new occupancy trigger Chapter 9 (sprinkler) thresholds? | Yes / No | If yes, automatic sprinklers are required in the area of change and in areas not separated by a firewall. | § 1011.2.1 |
| Size of new occupancy area | Less than 10% of building area (special exception contexts) | Some structural/seismic and other numeric sections allow exceptions when < 10% (cumulative changes considered). Not a blanket exemption for separation rules. | See exceptions in CH. 5/506/1006 (exceptions re: 10%) |
How to apply the rule (stepwise)
- Identify that a change of occupancy classification is proposed and confirm § 1011.1 applies.
- Determine whether the portion being changed is mechanically/physically separated from the remainder of the building. Separation must be by fire barrier or horizontal assemblies having the fire‑resistance rating required for the occupancies per IBC Table 508.4 or IRC R302 (or approved alternative). § 1302.1.2.
- If the separation meets the required rating: evaluate and upgrade only the separated portion under Chapter 10/§ 1011 and Chapter 13 applicability (as applicable). § 1302.1.2.
- If separation is absent or inadequate: apply the change‑of‑occupancy provisions for each occupancy to the entire building; where provisions conflict, the more restrictive (greater public safety) requirement prevails. § 1302.1.2.
- Independently check fire protection triggers in § 1011.2 (sprinklers, alarms) — even a separated portion may require sprinklers in the area of change and in any building areas that are not separated by a firewall from the changed area. § 1011.2.1.
Exceptions & special cases
- If the changed portion is separated by fire barriers/horizontal assemblies meeting the required rating (or an approved alternative), then only that portion must be evaluated for compliance — § 1302.1.2.
- If the changed portion is not separated with the required rated construction, the entire building must comply with the change‑of‑occupancy provisions for each occupancy; where provisions conflict, the more protective requirement applies to the entire building. § 1302.1.2.
- Automatic sprinkler requirement: where Chapter 9 of the CBC requires sprinklers for the new occupancy (or a changed threshold), sprinklers must be installed within the area of change and in areas not separated by a firewall from the change area — § 1011.2.1.
- Removal of an existing nonrequired sprinkler system can be authorized only when conditions in § 1011.2.1.1 are satisfied (system not required for new construction; exposed public portions removed; system was not installed for special features).
- Numerical “small‑area” exceptions in other sections (for example, some structural/seismic or load provisions) may allow relief where the new occupancy area is less than 10 percent of the building area — but the partial‑separation rule in § 1302.1.2 is independent and still requires rated separation when you want to limit evaluation to the portion. Cumulative occupancy changes over time must be considered.
Common mistakes
- Thinking “any partition” qualifies as a separation. The code requires rated fire barriers or horizontal assemblies with the fire‑resistance rating required by the referenced tables — not just a tenant demising wall. § 1302.1.2.
- Forgetting sprinkler/alarm implications. Even with rated separation, § 1011.2.1 can require sprinklers in the change area and adjacent areas not separated by a firewall.
- Assuming the “less than 10%” rule automatically allows partial change without review. The 10% thresholds appear in specific exceptions (structural/seismic, etc.) and do not override the separation requirement in § 1302.1.2; also the code requires considering cumulative effects of small changes.
- Confusing a change in use (different activity within same occupancy group) with a change of occupancy classification; the latter triggers § 1011.1 and related requirements. The code defines these terms and treats them differently.
Worked example — concrete scenario
Scenario: single‑story 10,000 ft² existing building currently Group B; owner proposes converting a 2,000 ft² tenant space to a Group A (assembly) use.
- Size check: 2,000 ft² is 20% of building area (not < 10%), so small‑area exceptions for other sections do not automatically apply.
- Separation check: owner installs a continuous fire barrier between the 2,000 ft² space and the rest of the building. The required fire‑resistance rating for that fire barrier must match the rating required for separating the particular occupancies per IBC Table 508.4 or IRC R302 (or an approved alternative). If the installed assembly meets that rating and is accepted by the code official, the changed portion qualifies as separated and only the 2,000 ft² portion must be evaluated and upgraded per the applicable change‑of‑occupancy provisions. § 1302.1.2.
- Fire protection check: determine whether Chapter 9 (CBC) requires an automatic sprinkler system for the new Group A area. If Chapter 9 requires sprinklers for the new occupancy (or the new occupancy raises system thresholds), sprinklers must be installed within the 2,000 ft² area and also in any parts of the building that are not separated by a firewall from that area. If the separation is a full fire barrier (acceptable firewall), sprinklers may be limited to the changed area per § 1011.2.1.
- If the demising partition is not rated to the required fire‑resistance, then the entire 10,000 ft² building must be evaluated and required upgrades applied as necessary per § 1302.1.2 (second paragraph).
Related provisions (CEBC)
- § 1302.1.2 — Partial change in occupancy (separation rule).
- § 1011.1 — General scope for change of occupancy classification.
- § 1011.2.1 — Automatic sprinkler requirements when occupancy change triggers Chapter 9 thresholds.
- § 1011.2.1.1 — Conditions and process for removal of nonrequired sprinkler systems.
- § 1004.1 — Fire protection requirements referencing Section 1011 when a change of occupancy occurs.
- § 1005.1 — Means of egress for portions undergoing change of occupancy (refers to § 1011).
- § 1304.1.2 — Submittal requirements for the investigation/evaluation where work is proposed (useful when applying for partial change).
- Change/definition references: change of occupancy and change of use definitions (see CBC/CEBC definitions) to distinguish types of work.
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 § 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.
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:
- 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).
- 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 § 10-3 High relevance — show source text
1003 Building Elements and Materials . . . . . . . . . . . . . . . . 10-3
1004 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
1005 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
1006 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
1007 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
1008 Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
1009 Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
1010 Other Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
1011 Change of Occupancy Classification . . . . . . . . . . . . . 10-5
CHAPTER 11 ADDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . .11-3
1101 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
1102 Heights and Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
1103 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
1104 Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
CHAPTER 12 HISTORIC BUILDINGS . . . . . . . . . . . . . . . . . .12-1
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CHAPTER 13 PERFORMANCE COMPLIANCE METHODS. . 13-3
1301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
1302 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
1303 Acceptance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-4
CEBC § 0.33 High relevance — show source text
Exceptions:
- 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.
- 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.
- 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.
- 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.
506.6 Enhanced classroom acoustics. In Group E occupancies, where the work area exceeds 50 percent of the building area, enhanced classroom acoustics shall be provided in all classrooms with a volume of 20,000 cubic feet (565 m [3] ) or less. Enhanced classroom acoustics shall comply with the reverberation time in Section 808 of ICC A117.1.
SECTION 507—HISTORIC BUILDINGS
507.1 Historic buildings. The provisions of the California Historical Building Code (Part 8, Title 24, C.C.R), shall apply to qualified historical buildings or properties.
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CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE
CHAPTER 5A – PRESCRIPTIVE COMPLIANCE METHOD [OSHPD 1]
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
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:
Alterations for accessibility required by the California Building Code, Chapter 11A.
Alterations that constitute substantial improvement in flood hazard areas, which shall comply with Sections 503.2, 701.3 or 1303.1.3.
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 § 101.4.8 High relevance — show source text
[OSHPD 1R, 2, 4 & 5] The provisions of the California Existing Building Code, Chapters 2, 3, 4 and 5 shall apply to all matters govern- ing the repairs, alterations, change of occupancy, additions and relocation of existing structures and portions thereof under OSHPD jurisdiction.
101.4.8 Wildland-urban interface. The provisions of Part 7, the California Wildland-Urban Interface Code shall apply to buildings and structures built in the wildland-urban interface (WUI) or a Fire Hazard Severity Zone.
SECTION 102—APPLICABILITY
[A] 102.1 General. Where there is a conflict between a general requirement and a specific requirement, the specific requirement shall be applicable. Where, in any specific case, different sections of this code specify different materials, methods of construction or other requirements, the most restrictive shall govern.
[A] 102.2 Other laws. The provisions of this code shall not be deemed to nullify any provisions of local, state or federal law.
[A] 102.3 Application of references. References to chapter or section numbers, or to provisions not specifically identified by number, shall be construed to refer to such chapter, section or provision of this code.
[A] 102.4 Referenced codes and standards. The codes and standards referenced in this code shall be considered to be part of the requirements of this code to the prescribed extent of each such reference and as further regulated in Sections 102.4.1 through 102.4.4.
[A] 102.4.1 Conflicts. Where conflicts occur between provisions of this code and referenced codes and standards, the provisions of this code shall apply.
[A] 102.4.2 Provisions in referenced codes and standards. Where the extent of the reference to a referenced code or standard includes subject matter that is within the scope of this code or the California Codes specified in Section 101.4, the provisions of this code or the California Codes specified in Section 101.4, as applicable, shall take precedence over the provisions in the referenced code or standard.
102.4.3 Code references. [OSHPD 1, 1R, 2, 3, 4, 5 & 6, DSA-SS & DSA-SS/CC] All reference to International Codes or other similar codes in referenced standards shall be replaced by equivalent provisions in the California Building Standards Codes.
102.4.4 Reference in standards. [OSHPD 1, 1R, 2, 3, 4, 5 & 6, DSA-SS & DSA-SS/CC] All references listed in reference standards shall be replaced by referenced standards listed in Chapter 35 of this code, where applicable, and shall include all amendments to the reference standards in this code.
[A] 102.5 Partial invalidity. In the event that any part or provision of this code is held to be illegal or void, this shall not have the effect of making void or illegal any of the other parts or provisions.
[A] 102.6 Existing structures. The legal occupancy of any structure existing on the date of adoption of this code shall be permitted to continue without change, except as otherwise specifically provided in this code, the California Existing Building Code or the Cali- fornia Fire Code .
CEBC § 17958.5 High relevance — show source text
Amendments, additions and deletions to this code adopted by a city, county, or city and county_ pursuant to California Health and Safety Code Sections 17958.5, 17958.7 and 18941.5, together with all applicable portions of this code, shall also become effective 180 days after publication of the California Building Standards Code by the California Building Standards Commission.
1.8.6.2 Findings, filings and rejections of local modifications. Prior to making any modifications or establishing more restrictive building standards, the governing body shall make express findings and filings, as required by California Health and Safety Code Section 17958.7, showing that such modifications are reasonably necessary due to local climatic, geological or topographical conditions. No modification shall become effective or operative unless the following requirements are met: 1. The express findings shall be made available as a public record. 2. A copy of the modification and express finding, each document marked to cross-reference the other, shall be filed with the California Building Standards Commission for a city, county, or city and county and with the Department of Housing and Community Development for fire protection districts. 3. The California Building Standards Commission has not rejected the modification or change.
Nothing in this section shall limit the authority of fire protection districts pursuant to California Health and Safety Code Section 13869.7(a).
SECTION 1.8.7—ALTERNATE MATERIALS, DESIGNS, TESTS AND METHODS OF CONSTRUCTION
1.8.7.1 General. The provisions of this code, as adopted by the Department of Housing and Community Development are not intended to prevent the use of any alternate material, appliance, installation, device, arrangement, design or method of construction not specifically prescribed by this code. Consideration and approval of alternates shall comply with Section 1.8.7.2 for local building departments and Section 1.8.7.3 for the Department of Housing and Community Development.
1.8.7.2 Local building departments. The building department of any city, county, or city and county may approve alternates for use in the erection, construction, reconstruction, movement, enlargement, conversion, alteration, repair, removal, demolition or arrangement of apartments, condominiums, hotels, motels, lodging houses, dwellings or accessory structures, except for the following: 1. Structures located in mobilehome parks as defined in California Health and Safety Code Section 18214. 2. Structures located in special occupancy parks as defined in California Health and Safety Code Section 18862.43. 3. Factory-built housing as defined in California Health and Safety Code Section 19971.
1.8.7.2.1 Approval of alternates. The consideration and approval of alternates by a local building department shall comply with the following procedures and limitations: 1. The approval shall be granted on a case-by-case basis. 2. Evidence shall be submitted to substantiate claims that the proposed alternate, in performance, safety and protection of life and health, conforms to, or is at least equivalent to, the standards contained in this code and other rules and regulations promulgated by the Department of Housing and Community Development. 3. The local building department may require tests performed by an approved testing agency at the expense of the owner or owner’s agent as proof of compliance. _4.
CEBC § 1304.1 High relevance — show source text
1304.1 General. For proposed work covered by this chapter, the building owner shall cause the existing building to be investigated and evaluated in accordance with the provisions of Sections 1304.1 through 1307.1.
[BS] 1304.1.1 Structural analysis. The owner shall have a structural analysis of the existing building made to determine adequacy of structural systems for the proposed alteration, addition or change of occupancy. The analysis shall demonstrate that the building with the work completed is capable of resisting the loads specified in Chapter 16 of the International Building Code .
1304.1.2 Submittal. The results of the investigation and evaluation as required in Section 1304.1, along with proposed compliance alternatives, shall be submitted to the code official.
1304.1.3 Determination of compliance. The code official shall determine whether the existing building, with the proposed addition, alteration or change of occupancy, complies with the provisions of this section in accordance with the evaluation process in Sections 1305.1 through 1307.1.
SECTION 1305—SCORING AND EVALUATION
1305.1 Safety categories. The evaluation shall be composed of three categories: fire safety, means of egress and general safety, as defined in Sections 1305.1.1 through 1305.1.3.
1305.1.1 Fire safety. Included within the fire safety category are the structural fire resistance, automatic fire detection, fire alarm, automatic sprinkler system and fire suppression system features of the facility.
1305.1.2 Means of egress. Included within the means of egress category are the configuration, characteristics and support features for means of egress in the facility.
1305.1.3 General safety. Included within the general safety category are the fire safety parameters and the means of egress parameters.
1305.2 Evaluation process. The evaluation process specified herein shall be followed in its entirety to evaluate existing buildings in Groups A, B, E, F, M, R, S and U. For existing buildings in Group I-2, the evaluation process specified herein shall be followed and applied to each and every individual smoke compartment. Table 1306.1 shall be utilized for tabulating the results of the evaluation. References to other sections of this code or other codes indicate that compliance with those sections is required in order to gain credit in the evaluation herein outlined. In applying this section to a building with mixed occupancies, where the separation between the mixed occupancies does not qualify for any category indicated in Section 1305.2.16, the score for each occupancy shall be determined, and the lower score determined for each section of the evaluation process shall apply to the entire building or to each smoke compartment for Group I-2 occupancies.
Where the separation between the mixed occupancies qualifies for any category indicated in Section 1305.2.16, the score for each occupancy shall apply to each portion or smoke compartment of the building based on the occupancy of the space.
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:
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.
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.
Reserved.
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 :
Hazardous locations.
Commercial garages, repair and storage.
Aircraft hangars.
Gasoline dispensing and service stations.
Bulk storage plants.
Spray application, dipping and coating processes.
Reserved.
Places of assembly.
Theaters, audience areas of motion picture and television studios, and similar locations.
Motion picture and television studios and similar locations.
Motion picture projectors.
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 § 1.1 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:
- 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).
- 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 § 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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3 A PROVISIONS FOR ALL COMPLIANCE METHODS
User notes:
About this chapter: Chapter 3A controls the compliance options for alteration, repair, addition, evaluation and change of occupancy of existing 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 Section 1.10.1 (OSHPD 1)].
SECTION 301 A —ADMINISTRATION
301 A .1 Applicability. The provisions of this chapter shall control the alteration, repair, addition and change of occupancy of existing structures for applications listed in Sections 1.10.1 [OSHPD 1] regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).
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.
CEBC § 1001.2.1 Medium 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:
- A building or portion thereof undergoes a change of occupancy.
- 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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[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.
CEBC § 1001.1 Medium relevance — show source text
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10 CHANGE OF OCCUPANCY
User notes:
About this chapter : The purpose of this chapter is to provide regulations for the circumstances where an existing building is subject to a change of occupancy or a change of occupancy classification. A change of occupancy is not to be confused with a change of occupancy classification. The California Building Code defines different occupancy classifications in Chapter 3 and special occupancy requirements in Chapter 4. Within specific occupancy classifications there can be many different types of actual activities that can take place. For instance, a Group A-3 occupancy classification deals with a wide variation of different types of activities, including bowling alleys and courtrooms, indoor tennis courts and dance halls. When a facility changes use from, for example, a bowling alley to a dance hall, the occupancy classification remains A-3, but the different uses could lead to drastically different code requirements. Therefore, this chapter deals with the special circumstances that are associated with a change in the use of a building within the same occupancy classification as well as a change of occupancy classification.
SECTION 1001—GENERAL
1001.1 Scope. The provisions of this chapter shalle a change of occupancy occurs, as defined in Section 202.
1001.2 Certificate of occupancy. A change of occupancy or a change of occupancy within a space where there is a different fire protection system threshold requirement in Chapter 9 of th apply where current California Building Code than exists in the current building or space shall not be made to any structure without the approval of the code official. A certificate of occupancy shall be issued where it has been determined that the requirements for the change of occupancy have been met.
1001.2.1 Change of use. Any work undertaken in connection with a change in use shall conform to the applicable requirements for the work as classified in Chapter 6 and to the requirements of Sections 1002 through 1010.
1001.2.2 Change of occupancy classification. Where a building undergoes a change of occupancy classification, the provisions of Sections 1002 through 1011 shall apply.
1001.2.2.1 Partial change of occupancy. Where a portion of an existing building undergoes a change of occupancy classification, Section 1011 shall apply.
1001.3 Certificate of occupancy required. A certificate of occupancy shall be issued where a change of occupancy occurs that results in a different occupancy classification as determined by the California Building Code .
SECTION 1002—SPECIAL USE AND OCCUPANCY
1002.1 Compliance with the building code. Where an existing building or part of an existing building undergoes a change of occupancy to one of the special use or occupancy categories as described in Chapter 4 in the California Building Code, the building shall comply with all of the requirements of Chapter 4 of the California Building Code applicable to the special use or occupancy.
1002.2 Incidental uses. Where a portion of a building undergoes a change of occupancy to one of the incidental uses listed in Table 509.1 of the California Building Code, the incidental use shall comply with Section 509 of the California Building Code applicable to the incidental use.
SECTION 1003—BUILDING ELEMENTS AND MATERIALS
1003.1 General. Building elements and materials in portions of buildings undergoing a change of occupancy classification shall comply with Section 1011.
SECTION 1004—FIRE PROTECTION
CEBC § 422.3 Medium 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:
- 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.
- 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 § 1004.1 Medium 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:
- A building or portion thereof undergoes a change of occupancy.
- 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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[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:
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.
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.
Reserved.
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.
CEBC § 1003.6 Medium relevance — show source text
MEANS OF EGRESS
Throughout a story in a Group I-2 occupancy, any change in elevation in portions of the means of egress that serve nonambulatory persons shall be by means of a ramp or sloped walkway.
[BE] 1003.6 Means of egress continuity. The path of egress travel along a means of egress shall not be interrupted by a building element other than a means of egress component as specified in this chapter. Obstructions shall not be placed in the minimum width or required capacity of a means of egress component except projections permitted by this chapter. The minimum width or required capacity of a means of egress system shall not be diminished along the path of egress travel.
[BE] 1003.7 Elevators, escalators and moving walks. Elevators, escalators and moving walks shall not be used as a component of a required means of egress from any other part of the building.
Exception: Elevators used as an accessible means of egress in accordance with Section 1009.4.
SECTION 1004—OCCUPANT LOAD
[BE] 1004.1 Design occupant load. In determining means of egress requirements, the number of occupants for whom means of egress facilities are provided shall be determined in accordance with this section.
[California Code of Regulations, Title 19, Division 1, §3.27] Overcrowding.
The number of occupants of any building, structure or portion thereof, shall not exceed the permitted or posted capacity.
[BE] 1004.2 Cumulative occupant loads. Where the path of egress travel includes intervening rooms, areas or spaces, cumulative occupant loads shall be determined in accordance with this section.
[BE] 1004.2.1 Intervening spaces or accessory areas. Where occupants egress from one or more rooms, areas or spaces through others, the design occupant load shall be the combined occupant load of interconnected accessory or intervening spaces. Design of egress path capacity shall be based on the cumulative portion of occupant loads of all rooms, areas or spaces to that point along the path of egress travel.
[BE] 1004.2.2 Adjacent levels for mezzanines. That portion of the occupant load of a mezzanine with required egress through a room, area or space on an adjacent level shall be added to the occupant load of that room, area or space.
[BE] 1004.2.3 Adjacent stories. Other than for the egress components designed for convergence in accordance with Section 1005.6, the occupant load from separate stories shall not be added.
[BE] 1004.3 Multiple-function occupant load. Where an area under consideration contains multiple functions having different occupant load factors, the design occupant load for such area shall be based on the floor area of each function calculated independently.
[BE] 1004.4 Multiple occupancies. Where a building contains two or more occupancies, the means of egress requirements shall apply to each portion of the building based on the occupancy of that space. Where two or more occupancies utilize portions of the same means of egress system, those egress components shall meet the more stringent requirements of all occupancies that are served.
CEBC § 26.8 Medium relevance — show source text
[BG] CELL (Group I-3 occupancy). A room within a housing unit in a detention or correctional facility used to confine inmates or prisoners.
[BS] CELL (masonry). A void space having a gross cross-sectional area greater than 1 [1] / 2 square inches (967 mm [2] ).
CELL COMPLEX. A cluster or group of cells or dormitories in a jail, prison or other detention facility, together with rooms used for accessory purposes, all of which open into the cell complex, and are used for functions such as dining, counseling, exercise, classrooms, sick call, visiting, storage, staff offices, control rooms or similar functions, and interconnecting corridors all within the cell complex.
[BG] CELL TIER. Levels of cells vertically stacked above one another within a housing unit.
CELL TIERS. Cells, dormitories and accessory spaces. Cell tiers are located one level above the other and do not exceed two levels per floor. A cell tier shall not be considered a story or mezzanine. The aggregate area of a tier within a housing pod shall not be greater than one-third of the floor area of that pod when supported by non-rated construction, and shall be no greater than two-thirds of the floor area of the pod when the tier floor and supporting elements meet the fire rating requirements of a floor.
CELLULAR CONCRETE. [HCD 1 & HCD 2] A lightweight product consisting of Portland cement and selected gas-forming chemicals or foaming agents which create homogeneous voids in the hardened concrete.
[BS] CEMENT PLASTER. A mixture of Portland or blended cement, Portland cement or blended cement and hydrated lime, masonry cement or plastic cement and aggregate and other approved materials as specified in this code.
CENTRAL CONTROL BUILDING. A secure building within a prison where the fire and life safety systems, communication systems, security systems and exterior lighting systems are monitored and where security operations necessitate the remote locking of required means of egress or at the door with a key to maintain a high security area
[BF] CERAMIC FIBER BLANKET. A high-temperature mineral wool insulation material made of alumina-silica ceramic or calcium magnesium silicate soluble fibers and weighing 4 to 10 pounds per cubic foot (pcf) (64 to 160 kg/m [3] ).
[BS] CERTIFICATE OF COMPLIANCE. A certificate stating that materials and products meet specified standards or that work was done in compliance with approved construction documents.
[A] CHANGE OF OCCUPANCY. Either of the following shall be considered as a change of occupancy where this code requires a greater degree of safety, accessibility, structural strength, fire protection, means of egress, ventilation or sanitation than is existing in the current building or structure:
- Any change in the occupancy classification of a building or structure.
- Any change in the purpose of, or a change in the level of activity within, a building or structure.
CHARACTERS. Letters, numbers, punctuation marks and typographic symbols.
CHARTER SCHOOL. A public school providing instruction from kindergarten through 12th grade, established pursuant to Education Code, Title 2, Division 4, Part 26.8, Section 47600, et seq.
CEBC § 1009.3 Medium 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:
- 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.
- 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:
- The system is not required for new construction.
- Portions of the system that are exposed to the public are removed.
- 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.
CEBC § 10-5 Medium relevance — show source text
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1011.5 Means of egress, general. Hazard categories in regard to life safety and means of egress shall be in accordance with Table 1011.5.
TABLE 1011.5—MEANS OF EGRESS HAZARD CATEGORIES Col2 RELATIVE HAZARD OCCUPANCY CLASSIFICATIONS 1 (Highest Hazard) H (Not Allowed) 2 I-2; I-3; I-4_(Not Allowed)_ 3 A; E; M; R-1; R-2; R-4 4 B; F-1; R-3; R-4, S-1 5 (Lowest Hazard) F-2; S-2; U 1011.5.1 Means of egress for change to a higher-hazard category. Where a change of occupancy classification is made to a higher-hazard category (lower number) as shown in Table 1011.5, the means of egress shall comply with the requirements of Chapter 10 of the California Building Code .
Exceptions:
Stairways shall be enclosed in compliance with the applicable provisions of Section 903.1.
Existing stairways including handrails and guards complying with the requirements of Chapter 9 shall be permitted for continued use subject to approval of the code official.
Any stairway replacing an existing stairway within a space where the pitch or slope cannot be reduced because of existing construction shall not be required to comply with the maximum riser height and minimum tread depth requirements.
Existing corridor walls constructed on both sides of wood lath and plaster in good condition or [1] / 2 -inch-thick (12.7 mm) gypsum wallboard shall be permitted. Such walls shall either terminate at the underside of a ceiling of equivalent construction or extend to the underside of the floor or roof next above.
Existing corridor doorways, transoms and other corridor openings shall comply with the requirements in Sections 804.7.1, 804.7.2 and 804.7.3.
Existing dead-end corridors shall comply with the requirements in Section 804.8.
An operable window complying with Section 1011.5.6 shall be accepted as an emergency escape and rescue opening.
In Group R-2.1 and I-2 facilities, required guards enclosing the occupiable roof areas shall be permitted to be greater than 48 inches (1219 mm) above the surface of the occupiable roof where the occupants, because of clinical needs, require restraint or containment as part of a function of a psychiatric or cognitive treatment area.
1011.5.2 Means of egress for change of use to an equal or lower-hazard category. Where a change of occupancy classification is made to an equal or lesser-hazard category (higher number) as shown in Table 1011.5, existing elements of the means of egress shall comply with the requirements of Section 905 for the new occupancy classification. Newly constructed or configured means of egress shall comply with the requirements of Chapter 10 of the California Building Code .
Exceptions:
CEBC § 1011.2.1.1 Medium relevance — show source text
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:
- The system is not required for new construction.
- Portions of the system that are exposed to the public are removed.
- 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.
1011.3 Interior finish. In areas of the building undergoing the change of occupancy classification, the interior finish of walls and ceilings shall comply with the requirements of the California Building Code for the new occupancy classification.
1011.4 Enhanced classroom acoustics. In Group E occupancies, where the work area is a Level 3 alteration, enhanced classroom acoustics shall be provided in all classrooms with a volume of 20,000 cubic feet (565 m [3] ) or less. Enhanced classroom acoustics shall comply with the reverberation time in Section 808 of ICC A117.1.
2025 CALIFORNIA EXISTING BUILDING CODE 10-5
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
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1011.5 Means of egress, general. Hazard categories in regard to life safety and means of egress shall be in accordance with Table 1011.5.
TABLE 1011.5—MEANS OF EGRESS HAZARD CATEGORIES Col2 RELATIVE HAZARD OCCUPANCY CLASSIFICATIONS 1 (Highest Hazard) H (Not Allowed) 2 I-2; I-3; I-4_(Not Allowed)_ 3 A; E; M; R-1; R-2; R-4 4 B; F-1; R-3; R-4, S-1 5 (Lowest Hazard) F-2; S-2; U 1011.5.1 Means of egress for change to a higher-hazard category. Where a change of occupancy classification is made to a higher-hazard category (lower number) as shown in Table 1011.5, the means of egress shall comply with the requirements of Chapter 10 of the California Building Code .
Exceptions:
- Stairways shall be enclosed in compliance with the applicable provisions of Section 903.1.
Frequently asked questions
When exactly does § 1302.1.2 let me limit the evaluation to the separated portion?
Only when the portion being changed is separated from the remainder of the building by fire barriers or horizontal assemblies having the fire‑resistance rating required for the occupancies (per IBC Table 508.4 or IRC R302) or an approved alternative — then only that separated portion must be evaluated.
If I provide a rated demising wall, do I still have to add sprinklers?
You must check the Chapter 9 sprinkler thresholds for the new occupancy. If Chapter 9 requires sprinklers for the new occupancy or the threshold changes, sprinklers are required in the area of change and in any parts of the building that are not separated by a firewall from that area. § 1011.2.1 governs this.
What if my demising partition is an approved “alternative” assembly?
An approved compliance alternative that provides equivalent performance to the required fire‑resistance rating is acceptable; the code allows approved alternatives in § 1302.1.2. Get the alternative approved by the code official and document compliance.
Does a small change (e.g., 5% of building area) mean I can avoid upgrades?
Some provisions include a 10% area exception for specific structural/seismic or other numeric requirements, but that does not automatically bypass the separation requirement in § 1302.1.2. The cumulative effect of occupancy changes over time is also considered.
Who decides if my separation assembly is acceptable?
The code official reviews the submittal (investigation/evaluation and proposed compliance alternatives). Use the submittal requirements in § 1304.1.2 and be prepared to show supporting documentation.
More in California Existing Building Code
- Administration and Definitions (Scope, enforcement, code official duties, definitions)
- Provisions for All Compliance Methods (general requirements that apply to all compliance options; Chapter 3 / 3A)
- Seismic retrofit and evaluation (Appendix A and seismic provisions/sections for evaluation and retrofit)
- Referenced Standards and Appendices (Chapter 16 and Appendices A–E, Resource A)
- Repairs (Chapter 4 — repair-specific rules for materials, means of egress, structural, MEP, etc.)
- Alterations — Level 1, Level 2, Level 3 (technical requirements for each alteration level; Chapters 7–9)
- Change of Occupancy and Additions (requirements for occupancy changes and additions; Chapters 10–11)
- Compliance Methods — Prescriptive, Work Area, Performance (Chapters 5, 6–11, 13)
- Relocated Buildings (requirements for buildings moved or relocated; Chapter 14)
- Construction Safeguards (site safety, means of egress and life-safety during construction; Chapter 15)
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