CEBC · California Existing Building Code
Alteration Level 2 — reconfiguration up to 50% and related systems
If your project reconfigures spaces or extends systems that affect **50% or less** of a building, it's a **Level 2 alteration** and must follow Chapter 8 of the California Existing Building Code — and also meet applicable Level 1 (Chapter 7) rules. Some limited system-only work and low movable partitions are excluded; new elements generally must meet the California Building Code unless an explicit exception applies.
Last reviewed: July 6, 2026
What the code requires — plain English
Level 2 alterations are alterations that involve space reconfiguration or the addition/extension of building systems where the work area is equal to or less than 50 percent of the building area. The work must comply with the Level 2 chapter (Chapter 8) and with Level 1 requirements (Chapter 7) as applicable. See § 603.1 and § 603.2 for the definition and application, and § 801.1 and § 802.1 for Chapter 8 scope and how section requirements apply to the work area.
The single most important rule: if the identified work area is ≤ 50% of the building area, treat the project as a Level 2 alteration and apply Chapter 8 (plus Chapter 7 where required). § 603.1 and § 801.1 set this threshold and scope.
Requirements in detail
1) Basic classification and trigger
- What makes it Level 2: Addition or elimination of any door or window, reconfiguration or extension of any system, or installation of additional equipment when the work area ≤ 50% of the building area (§ 603.1).
- Not Level 2 (exception): Movement/addition of nonfixed and movable fixtures, cases, racks, counters and partitions not over 5 feet 9 inches (1753 mm) in height are not Level 2 work (§ 603.1 Exception).
- Application: Level 2 projects must comply with Chapter 7 (Level 1) requirements where applicable and the special requirements in Chapter 8 (§ 603.2 and § 801.2).
2) System-only work: when work-area rules do not apply
- If the alteration is limited solely to one or more of these, the work-area-based Chapter 8 provisions are not applicable (they are treated differently):
- Mechanical systems, electrical systems, fire protection systems and hazardous materials abatement
- Windows, hardware, operating controls, electrical outlets and signs
- Work primarily to increase accessibility
(See § 801.3.)
3) New elements and code compliance
- New construction elements, components, systems and spaces installed as part of a Level 2 alteration must comply with the California Building Code (CBC) — with certain listed exceptions in § 801.4 (for example, added windows need not meet CBC light/ventilation).
4) Where the Section 802 provisions apply
- § 802.1 limits the requirements of Section 802 to the Level 2 work areas, but some Section 802 provisions apply beyond the immediate work area where the text specifically requires it.
Decision table — quick thresholds & effects
| Decision dimension | Value / threshold | Effect (what it triggers) | Code Reference |
|---|---|---|---|
| Work-area percentage | ≤ 50% of building area | Project is Level 2; apply Chapter 8 and Level 1 requirements | § 603.1, § 603.2 |
| Work type examples | Add/eliminate door/window; reconfigure/extend systems; install equipment | Typical Level 2 scope — see Chapter 8 requirements | § 603.1 |
| Movable partitions limit | ≤ 5 ft‑9 in (1753 mm) height | These changes are NOT Level 2 | § 603.1 Exception |
| System-only scope exemption | Mechanical, electrical, fire protection, abatement, windows/controls/outlets/signs, accessibility work | Chapter 8 work-area requirements need not apply | § 801.3 |
| New elements compliance | — | New elements must meet CBC unless exception applies | § 801.4 |
| Section 802 coverage | Work area and beyond where specified | Section 802 applies within Level 2 work areas; some requirements reach past work area | § 802.1 |
Exceptions & special cases
- If the reconfiguration exists solely to meet accessibility mandates under § 306.7.1, the project may be permitted to comply with Chapter 7 (Level 1) instead of Chapter 8 (see § 801.1 Exception).
- System-only work (mechanical, electrical, fire protection, hazardous-material abatement, limited window/hardware/outlet/sign work, and accessibility upgrades) is specifically called out so that the Level 2 work-area provisions are not applied in those limited situations (§ 801.3).
- New structural members and connections may be allowed to follow alternative design criteria per § 302 (cross-referenced in § 801.4 Exception 6). If you rely on that exception, confirm the specific alternative criteria allowed.
If a specific required detail from Chapter 8 or Chapter 7 is not covered in the retrieved excerpts, state law requires consulting the CEBC text for the exact wording — the excerpts used here establish scope and the principal triggers but do not reproduce all technical requirements.
Common mistakes
- Misclassifying low-height movable partitions (≤ 5 ft‑9 in) as Level 2 — these are excluded under § 603.1 Exception.
- Treating every system work as Level 2 instead of checking the system-only exemption in § 801.3 (mechanical, electrical, fire protection, abatement, certain window/hardware/outlet/sign work, accessibility work).
- Forgetting that Level 2 work must also meet Level 1/Chapter 7 requirements where applicable (§ 603.2, § 801.2). Always read Chapter 7 and Chapter 8 together.
- Overlooking that new elements introduced by the alteration must comply with the CBC (unless a specific exception applies) — see § 801.4.
- Failing to correctly identify the work area on construction documents — the CEBC requires the work area, as defined in Chapter 2, to be identified on the construction documents (see § 601.2).
Worked example
Scenario:
- Existing small office building = 10,000 sq ft gross area.
- Planned work: Remove two interior walls and add one new exterior window; relocate/build-out HVAC ductwork and add a kitchenette totaling 4,500 sq ft of floor area within the building.
Analysis:
- Calculate work-area percent: 4,500 / 10,000 = 45% → ≤ 50%, so this is a Level 2 alteration under § 603.1.
- Because it's Level 2, apply Chapter 8 requirements (§ 801.1) and the Level 1 requirements of Chapter 7 as applicable (§ 603.2, § 801.2). The HVAC extension and kitchenette are system changes and new elements that must meet the CBC where required (§ 801.4).
- If the work had been only replacing HVAC diffusers and changing light switches (system-only tasks listed in § 801.3), the Chapter 8 work-area rules might not apply; but because the scope here includes space reconfiguration and a new window, Level 2 applies.
Practical steps for the designer/owner:
- Clearly identify and show the work area on plans (Chapter 2 definition; see § 601.2).
- List all system work and confirm which items are subject to Chapter 8 vs. which fall under the system-only exemption in § 801.3.
- Demonstrate compliance with Chapter 7 where those provisions apply, and apply CBC requirements for any new elements per § 801.4.
Related provisions (CEBC sections)
- § 603.1 — Definition/scope of Level 2 alterations (work‑area threshold ≤ 50%).
- § 603.2 — Application: Level 2 must also meet Chapter 7 requirements where applicable.
- § 801.1 — Chapter 8 scope; Level 2 alterations must comply with Chapter 8.
- § 801.2 — Requirement that Level 2 work also comply with Chapter 7 (Level 1) in addition to Chapter 8.
- § 801.3 — System installations and the list of work for which Chapter 8 work-area rules are not applicable.
- § 801.4 — New elements installed as part of Level 2 alterations must comply with the CBC, with listed exceptions.
- § 802.1 — Limits Section 802 requirements to Level 2 work areas and notes when they apply beyond the work area.
- § 601.2 — Requires the work area to be identified on construction documents (Chapter 2 defines the term).
Code references
Grounded in the retrieved California Existing Building Code — click a citation to read the verbatim passage:
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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8 ALTERATIONS—LEVEL 2
User notes:
About this chapter: Like Chapter 7, the purpose of this chapter is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, building spaces and building structural system when a building is being altered. This chapter is distinguished from Chapters 7 and 9 by involving space reconfiguration that could be up to and including 50 percent of the area of the building. In contrast, Level 1 alterations (Chapter 7) do not involve space reconfiguration, and Level 3 alterations (Chapter 9) involve extensive space reconfiguration that exceeds 50 percent of the building area. Depending on the nature of alteration work, its location within the building, and whether it encompasses one or more tenants, improvements and upgrades could be required for the open floor penetrations, sprinkler system or the installation of additional means of egress such as stairs or fire escapes.
SECTION 801—GENERAL
801.1 Scope. Level 2 alterations as described in Section 603 shall comply with the requirements of this chapter.
Exception: Buildings in which the reconfiguration is exclusively the result of compliance with the accessibility requirements of Section 306.7.1 shall be permitted to comply with Chapter 7.
801.2 Alteration Level 1 compliance. In addition to the requirements of this chapter, all work shall comply with the requirements of Chapter 7.
801.3 System installations. Requirements related to work area are not applicable where the Level 2 alterations are limited solely to one or more of the following:
- Mechanical systems, electrical systems, fire protection systems and abatement of hazardous materials.
- Windows, hardware, operating controls, electrical outlets and signs.
- Alterations undertaken for the primary purpose of increasing the accessibility of a facility.
801.4 Compliance. New construction elements, components, systems and spaces shall comply with the requirements of the Califor- nia Building Code .
Exceptions:
Where windows are added they are not required to comply with the light and ventilation requirements of the California Building Code .
Newly installed electrical equipment shall comply with the requirements of Section 806.
The length of dead-end corridors in newly constructed spaces shall only be required to comply with the provisions of Section 804.8.
The minimum ceiling height of the newly created habitable and occupiable spaces and corridors shall be 7 feet (2134 mm).
Where 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).
New structural members and connections shall be permitted to comply with alternative design criteria in accordance with Section 302.
SECTION 802—BUILDING ELEMENTS AND MATERIALS
802.1 Scope. The requirements of this section are limited to work areas in which Level 2 alterations are being performed and shall apply beyond the work area where specified.
CEBC § 1.10.1 High relevance — show source text
Chapter 5A Prescriptive Compliance Method.
Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 6 Classification of Work.
Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.
Chapter 7 Alterations—Level 1.
Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.
Chapter 8 Alterations—Level 2.
A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.
Chapter 9 Alterations—Level 3.
Chapter 9 provides the technical requirements for those existing buildings that undergo Level 3 alterations. Level 3 alterations are those involving alterations that cover 50 percent of the aggregate area of the building. Under certain situations, this chapter also intends to improve the safety of certain building features beyond the work area and in other parts of the building where no alteration work might be taking place.
Chapter 10 Change of Occupancy.
The purpose of Chapter 10 is to address existing buildings that are subject to a change of occupancy. This chapter is an assembly of requirements to upgrade safety without having to comply fully as a new building. A change of occupancy classification is considered a change of occupancy, however, it will involve a higher level of regulation since the use of the building has made a more significant change.
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Chapter 11 Additions.
Chapter 11 provides the requirements for additions, which are considered new construction. The requirements focus on safely integrating the addition with the existing building. This includes issues such as limiting the overall height and area of the building where the addition is not separated by a fire wall.
Chapter 12 Historic Buildings —Reserved
Chapter 12 is not adopted by the State of California. Historic buildings and structures shall comply with Part 8, Title 24, California Code of Regulations.
Chapter 13 Performance Compliance Methods.
Chapter 13 allows for existing buildings to be evaluated to show that alterations or a change of occupancy, while not meeting new construction requirements, will provide a level of safety to demonstrate compliance. Provisions are based on a numerical scoring system involving 21 safety parameters where, when evaluated, such buildings must meet a minimum overall safety score.
CEBC § 601.1.1 High relevance — show source text
1|||X|||||||||||||||||||||| |601.1.1|||X|||||||||||||||||||||| |607.1|||X||||||||||||||||||||||
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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6 CLASSIFICATION OF WORK
User notes:
About this chapter: Chapter 6 provides an overview of the Work Area Method available as an option for rehabilitation of a building. The chapter defines the different classifications of alterations and provides general requirements for alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in Chapters 7 through 11.
SECTION 601—GENERAL
601.1 Scope. The provisions of this chapter shall be used in conjunction with Chapters 7 through 11 and shall apply to the alteration, addition and change of occupancy of existing structures, as referenced in Section 301.3.2. The work performed on an existing building shall be classified in accordance with this chapter. Historic buildings and structures shall comply with Part 8, Title 24, C.C.R.
Exceptions: 1. [SFM] Use of Chapters 6-11 is not permitted in H, I and L, R-2.1, R-3.1 occupancies and high-rise buildings. 2. [BSC] Use of Chapters 6-11 is not permitted in occupancies, buildings and applications regulated by Building Standards Commission and listed in Section 1.2.
601.1.1 Compliance with other alternatives. Alterations, additions and changes of occupancy to existing structures shall comply with the provisions of Chapters 7 through 11 or with one of the alternatives provided in Section 301.3.
601.2 Work area. The work area, as defined in Chapter 2, shall be identified on the construction documents.
SECTION 602—ALTERATION—LEVEL 1
602.1 Scope. Level 1 alterations include the removal and replacement or the covering of existing materials, elements, equipment or fixtures using new materials, elements, equipment or fixtures that serve the same purpose.
602.2 Application. Level 1 alterations shall comply with the provisions of Chapter 7.
SECTION 603—ALTERATION—LEVEL 2
603.1 Scope. Level 2 alterations include the addition or elimination of any door or window, the reconfiguration or extension of any system, or the installation of any additional equipment, and shall apply where the work area is equal to or less than 50 percent of the building area.
Exception: The movement or addition of nonfixed and movable fixtures, cases, racks, counters and partitions not over 5 feet 9 inches (1753 mm) in height shall not be considered a Level 2 alteration.
603.2 Application. Level 2 alterations shall comply with the provisions of Chapter 7 for Level 1 alterations as well as the provisions of Chapter 8.
SECTION 604—ALTERATION—LEVEL 3
CEBC § 1.10.1 High relevance — show source text
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Chapter 3 Provisions for All Compliance Methods.
Chapter 3 guides the use of the three compliance methods of the CEBC and provides requirements that apply globally. The globally applicable requirement include general requirements related to buildings materials and other applicable codes, storm shelters, structural loads, in-situ load tests, accessibility, smoke alarms, carbon monoxide detection and exterior wall coverings.
Chapter 3A Provisions for All Compliance Methods.
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 Sections 1.10.1 (OSHPD 1).
Chapter 4 Repairs.
Chapter 4, a chapter independent of the three compliance methods, governs the repair of existing buildings. The provisions define conditions under which repairs may be made using materials and methods like those of the original construction or the extent to which repairs must comply with requirements for new buildings.
Chapter 4A Repairs.
Chapter 4A governs the repair of existing buildings regulated by the Department of Health Care Access and Information/Office of State- wide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 5 Prescriptive Compliance Method.
Chapter 5 provides one of the three main options of compliance available in the CEBC for buildings and structures undergoing alteration, addition or change of occupancy. The base requirements are more administrative in nature. The structural triggers for upgrades are consistent with the Work Area Method.
Chapter 5A Prescriptive Compliance Method.
Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 6 Classification of Work.
Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.
Chapter 7 Alterations—Level 1.
Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.
Chapter 8 Alterations—Level 2.
A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.
Chapter 9 Alterations—Level 3.
CEBC § 901.1 High relevance — show source text
In contrast, Level 1 alterations do not involve space reconfiguration, and Level 2 alterations involve extensive space reconfiguration that does not exceed 50 percent of the building area. Depending on the nature of alteration work, its location within the building, and whether it encompasses one or more tenants, improvements and upgrades could be required for the open floor penetrations, sprinkler system or the installation of additional means of egress such as stairs or fire escapes. At times and under certain situations, this chapter also is intended to improve the safety of certain building features beyond the work area and in other parts of the building where no alteration work might be taking place.
SECTION 901—GENERAL
901.1 Scope. Level 3 alterations as described in Section 604 shall comply with the requirements of this chapter.
901.2 Compliance. In addition to the provisions of this chapter, work shall comply with all of the requirements of Chapters 7 and 8. The requirements of Sections 802, 803, 804 and 805 shall apply within all work areas whether or not they include exits and corridors shared by more than one tenant and regardless of the occupant load.
Exception: Buildings in which the reconfiguration of space affecting exits or shared egress access is exclusively the result of compliance with the accessibility requirements of Section 306.7.1 shall not be required to comply with this chapter.
SECTION 902—SPECIAL USE AND OCCUPANCY
902.1 Reserved.
902.2 Group R-2.1 occupancies. Group R-2.1 occupancies shall be classified in accordance with Section 308.2 of the California Build- ing Code .
902.2.1 Smoke barriers in Group R-2.1 . In Group R-2.1 occupancies where the work area is on a story used for sleeping rooms for more than 30 care recipients, the story shall be divided into not fewer than two compartments by smoke barrier walls in accordance with Section 420.6 of the California Building Code .
902.3 Ambulatory care facilities. Where a Level 3 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 incapable of self-preservation at any time.
SECTION 903—BUILDING ELEMENTS AND MATERIALS
903.1 Existing shafts and vertical openings. Existing stairways that are part of the means of egress shall be enclosed in accordance with Section 802.2.1 from the highest work area floor to, and including, the level of exit discharge and all floors below.
903.2 Fire partitions in Group R-3. Fire separation in Group R-3 occupancies shall be in accordance with Section 903.2.1.
CEBC § 2.1 High relevance — show source text
2.1 Exceptions 4 – 9 and
13-14||||†|†|||||||||||||||||||| |802.3||||†|†|||||||||||||||||||| |803.2|||X|||||||||||||||||||||| |803.2.3||||†|†|||||||||||||||||||| |803.3_Reserved_|||X|||||||||||||||||||||| |803.4|||X|||||||||||||||||||||| |803.4.1|||X|||||||||||||||||||||| |804.3_Reserved_|||X|||||||||||||||||||||| |804.5|||X|||||||||||||||||||||| |804.5.1.2|||X|||||||||||||||||||||| |804.5.1.2.1|||X|||||||||||||||||||||| |804.5.3||||†|†|||||||||||||||||||| |804.6.3|||X|||||||||||||||||||||| |804.6.4||||†|†|||||||||||||||||||| |804.6.4.1|||X|||||||||||||||||||||| |804.7.1|||X|||||||||||||||||||||| |804.7.2|||X|||||||||||||||||||||| |804.8|||X|||||||||||||||||||||| |804.12||||†|†|||||||||||||||||||| |804.13|||X|||||||||||||||||||||| |804.13.1|||X|†|†|||||||||||||||||||| |804.14.2 Exceptions||||†|†|||||||||||||||||||| |806.2|||X|†|†|||||||||||||||||||| |806.3|||X|†|†|||||||||||||||||||| |808_Reserved_|||X||||||||||||||||||||||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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8 ALTERATIONS—LEVEL 2
User notes:
About this chapter: Like Chapter 7, the purpose of this chapter is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, building spaces and building structural system when a building is being altered. This chapter is distinguished from Chapters 7 and 9 by involving space reconfiguration that could be up to and including 50 percent of the area of the building. In contrast, Level 1 alterations (Chapter 7) do not involve space reconfiguration, and Level 3 alterations (Chapter 9) involve extensive space reconfiguration that exceeds 50 percent of the building area. Depending on the nature of alteration work, its location within the building, and whether it encompasses one or more tenants, improvements and upgrades could be required for the open floor penetrations, sprinkler system or the installation of additional means of egress such as stairs or fire escapes.
SECTION 801—GENERAL
801.1 Scope. Level 2 alterations as described in Section 603 shall comply with the requirements of this chapter.
CEBC § 601.1.1 High relevance — show source text
601.1.1 Compliance with other alternatives. Alterations, additions and changes of occupancy to existing structures shall comply with the provisions of Chapters 7 through 11 or with one of the alternatives provided in Section 301.3.
601.2 Work area. The work area, as defined in Chapter 2, shall be identified on the construction documents.
SECTION 602—ALTERATION—LEVEL 1
602.1 Scope. Level 1 alterations include the removal and replacement or the covering of existing materials, elements, equipment or fixtures using new materials, elements, equipment or fixtures that serve the same purpose.
602.2 Application. Level 1 alterations shall comply with the provisions of Chapter 7.
SECTION 603—ALTERATION—LEVEL 2
603.1 Scope. Level 2 alterations include the addition or elimination of any door or window, the reconfiguration or extension of any system, or the installation of any additional equipment, and shall apply where the work area is equal to or less than 50 percent of the building area.
Exception: The movement or addition of nonfixed and movable fixtures, cases, racks, counters and partitions not over 5 feet 9 inches (1753 mm) in height shall not be considered a Level 2 alteration.
603.2 Application. Level 2 alterations shall comply with the provisions of Chapter 7 for Level 1 alterations as well as the provisions of Chapter 8.
SECTION 604—ALTERATION—LEVEL 3
604.1 Scope. Level 3 alterations apply where the work area exceeds 50 percent of the building area.
604.2 Application. Level 3 alterations shall comply with the provisions of Chapters 7 and 8 for Level 1 and 2 alterations, respectively, as well as the provisions of Chapter 9.
SECTION 605—CHANGE OF OCCUPANCY
605.1 Scope. Change of occupancy provisions apply where the activity is classified as a change of occupancy as defined in Chapter 2.
605.2 Application. Changes of occupancy shall comply with the provisions of Chapter 10.
SECTION 606—ADDITIONS
606.1 Scope. Provisions for additions shall apply where work is classified as an addition as defined in Chapter 2.
606.2 Application. Additions to existing buildings shall comply with the provisions of Chapter 11.
SECTION 607—HISTORIC BUILDINGS
607.1 Scope. 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 7 – ALTERATIONS—LEVEL 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 § 902.1 High relevance — show source text
2 Exception||||†|†|||||||||||||||||||| |902.1_Reserved_|||X|||||||||||||||||||||| |902.2 – 902.2.1|||X|||||||||||||||||||||| |902.2 – 902.3||||†|†|||||||||||||||||||| |903.4||||†|†|||||||||||||||||||| |904.1|||X|||||||||||||||||||||| |904.2|||X|||||||||||||||||||||| |904.2.1|||X|||||||||||||||||||||| |908||||†|†||||||||||||||||||||
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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9 ALTERATIONS—LEVEL 3
User notes:
About this chapter : Chapter 9 provides the technical requirements for those existing buildings that undergo Level 3 alterations. The purpose of this chapter is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, building spaces and building structural system. This chapter is distinguished from Chapters 7 and 8 by involving alterations that cover 50 percent or more of the aggregate area of the building. In contrast, Level 1 alterations do not involve space reconfiguration, and Level 2 alterations involve extensive space reconfiguration that does not exceed 50 percent of the building area. Depending on the nature of alteration work, its location within the building, and whether it encompasses one or more tenants, improvements and upgrades could be required for the open floor penetrations, sprinkler system or the installation of additional means of egress such as stairs or fire escapes. At times and under certain situations, this chapter also is intended to improve the safety of certain building features beyond the work area and in other parts of the building where no alteration work might be taking place.
SECTION 901—GENERAL
901.1 Scope. Level 3 alterations as described in Section 604 shall comply with the requirements of this chapter.
901.2 Compliance. In addition to the provisions of this chapter, work shall comply with all of the requirements of Chapters 7 and 8. The requirements of Sections 802, 803, 804 and 805 shall apply within all work areas whether or not they include exits and corridors shared by more than one tenant and regardless of the occupant load.
Exception: Buildings in which the reconfiguration of space affecting exits or shared egress access is exclusively the result of compliance with the accessibility requirements of Section 306.7.1 shall not be required to comply with this chapter.
SECTION 902—SPECIAL USE AND OCCUPANCY
902.1 Reserved.
902.2 Group R-2.1 occupancies. Group R-2.1 occupancies shall be classified in accordance with Section 308.2 of the California Build- ing Code .
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:
- 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 § 317.3.2 High relevance — show source text
2. There are changes in risk category. 3. The modification to the structural components increases the seismic forces in or strength requirements of any structural component of the existing structure by more than 10 percent cumulative since the original construction, unless the component has the capacity to resist the increased forces determined in accordance with Section 319. If the building’s seismic base shear capacity has been increased since the original construction, the percent change in base shear may be calculated relative to the increased value.
4. Structural elements need repair where the damage has reduced the lateral-load-resisting capacity of the structural system by more than 10 percent. 5. Changes in live or dead load increase story shear by more than 10 percent.
317.3.2 Public school buildings. [DSA-SS] For public schools, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.
317.3.3 Community college buildings. [DSA-SS/CC] For community colleges, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.
317.4 Evaluation required. If the criteria in Section 317.3 apply to the project under consideration, the design professional of record shall provide an evaluation in accordance with Section 317 to determine the seismic performance of the building in its current configuration and condition. If the structure's seismic performance as required by Section 317.5 is evaluated as satisfactory and the peer reviewer(s), when Method B of Section 321 is used, concur, then no structural retrofit is required.
317.5 Minimum seismic design performance levels for structural and nonstructural components. Following the notations of ASCE 41, the seismic requirements for design and assessment are based upon a prescribed Seismic Hazard Level (BSE-1N, BSE-2N, BSE-1E, BSE-R or BSE-C), a specified structural performance level (S-1 through S-5) and a nonstructural performance level (N-A through N-E). The minimum seismic performance criteria are given in Table 317.5 according to the Building Regulatory Authority and the Risk Category as determined in Chapter 16 of the California Building Code or by the regulatory authority. The building shall be evaluated in accordance with a Tier 3 Systematic Evaluation and Retrofit per ASCE 41 Chapter 6 for both the Level 1 and Level 2 performance levels, and the more restrictive requirements shall apply.
Exception: If the floor area of an addition is greater than the larger of 50 percent of the floor area of the original building or 1,000 square feet (93 m [2] ), then the Table 317.5 entries for BSE-R (or BSE-1E) and BSE-C are replaced by BSE-1N and BSE-2N, respectively.
|TABLE 317.5—SEISMIC PERFORMANCE REQUIREMENTS2,
CEBC § 701.1 Medium relevance — show source text
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter X X Adopt Entire Chapter as
amended (amended
sections listed below)X Adopt only those sections
that are listed belowChapter / Section 701.1 X 702.7 X 703.2 X 703.2.1 X 703.2.2 X 703.3 X 704.3 † † 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 7-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
7-2 2025 CALIFORNIA EXISTING BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
7 ALTERATIONS—LEVEL 1
User notes:
About this chapter: Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 603, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter, similar to other chapters of this code, covers all building-related subjects, such as structural, mechanical, plumbing, electrical and accessibility as well as the fire and life safety issues when the alterations are classified as Level 1. The purpose of this chapter is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, building spaces and building structural system. This chapter is distinguished from Chapters 8 and 9 by involving only replacement of building components with new components. In contrast, Level 2 alterations involve more space reconfiguration, and Level 3 alterations involve more extensive space reconfiguration, exceeding 50 percent of the building area.
SECTION 701—GENERAL
CEBC § 2.2 Medium relevance — show source text
2.2_|||X|||||||||||||||||||||| |703.3|||X|||||||||||||||||||||| |704.3||||†|†||||||||||||||||||||
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 7-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
7-2 2025 CALIFORNIA EXISTING BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
7 ALTERATIONS—LEVEL 1
User notes:
About this chapter: Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 603, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter, similar to other chapters of this code, covers all building-related subjects, such as structural, mechanical, plumbing, electrical and accessibility as well as the fire and life safety issues when the alterations are classified as Level 1. The purpose of this chapter is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, building spaces and building structural system. This chapter is distinguished from Chapters 8 and 9 by involving only replacement of building components with new components. In contrast, Level 2 alterations involve more space reconfiguration, and Level 3 alterations involve more extensive space reconfiguration, exceeding 50 percent of the building area.
SECTION 701—GENERAL
701.1 Scope. Level 1 alterations as described in Section 602 shall comply with the requirements of this chapter. Alterations to historic buildings and structures shall comply with Part 8, Title 24, C.C.R.
701.2 Conformance. An existing building or portion thereof shall not be altered such that the building becomes less safe than its existing condition.
Exception: Where the current level of safety or sanitation is proposed to be reduced, the portion altered shall conform to the requirements of the California Building Code .
[BS] 701.3 Flood hazard areas. In flood hazard areas, alterations that constitute substantial improvement shall require that the building comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable.
SECTION 702—BUILDING ELEMENTS AND MATERIALS
702.1 Interior finishes. Newly installed interior wall and ceiling finishes shall comply with Chapter 8 of the California Building Code .
702.2 Interior floor finish. New interior floor finish, including new carpeting used as an interior floor finish material, shall comply with Section 804 of the California Building Code .
702.3 Interior trim. Newly installed interior trim materials shall comply with Section 806 of the California Building Code .
702.4 Window fall prevention. In Group R-2 or R-3 buildings containing dwelling units and one- and two-family dwellings and townhouses regulated by the California Residential Code, window opening control devices or other window fall prevention devices complying with ASTM F2090 shall be installed where an existing window is replaced and where all of the following apply to the replacement window:
- The window is operable.
- One of the following applies: 2.1.
Frequently asked questions
Can small freestanding counters be moved without triggering Level 2?
Yes — nonfixed and movable fixtures, cases, racks, counters and partitions not over 5 ft‑9 in (1753 mm) high are explicitly excluded from Level 2 classification under § 603.1 Exception.
If I only upgrade the HVAC system, do I have to treat the project as Level 2?
Not necessarily. System-only work such as mechanical, electrical, fire protection, hazardous-material abatement, and limited window/hardware/outlet/sign work may be exempt from the Chapter 8 work-area rules under § 801.3. Evaluate whether space reconfiguration or other Level 2 triggers are present.
Do new windows added during a Level 2 project need to meet CBC light and ventilation rules?
Per § 801.4 Exception 1, where windows are added they are not required to comply with the CBC light and ventilation requirements — but other CBC requirements may still apply. Confirm other applicable Chapter 8/7 provisions.
Must Level 2 projects also meet Chapter 7?
Yes. § 603.2 and § 801.2 require Level 2 alterations to comply with the provisions of Chapter 7 (Level 1) in addition to Chapter 8 where those Level 1 provisions apply.
Where do I show the work area on my submittal?
The CEBC requires the work area (as defined in Chapter 2) to be identified on the construction documents (see § 601.2).
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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