CBC · California Building Code

Where are the technical requirements for Level 1, 2 and 3 alterations?

For a homeowner: the CEBC organizes alterations by level — simple replacements are Level 1 (Chapter 7), reconfigurations up to half the building are Level 2 (Chapters 7+8), and larger reconfigurations are Level 3 (Chapters 7+8+9); the work area must be shown on plans and each level chapter contains the specific technical requirements you must follow.

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Last reviewed: July 5, 2026

What the code requires — 2-4 sentences

The California Existing Building Code (CEBC) assigns technical requirements for existing‑building alterations by "level" and places the detailed, technical rules for each level in separate chapters: Level 1 requirements are in Chapter 7 (see §701.1), Level 2 requirements are in Chapter 8 (see §801.1), and Level 3 requirements are in Chapter 9 (see §901.1). The Chapter/section that defines each level and which chapters apply are in the Classification of Work (Chapter 6: §602, §603, §604) and each level chapter contains the technical requirements that must be met. The CEBC also requires the work area to be identified on the construction documents (§601.2).

Requirements in detail

High‑level mapping (decision rules)

  • Level 1 = replacement/covering of existing materials/equipment/fixtures with like purpose — governed by Chapter 7 (§602.1 and §701.1).
  • Level 2 = addition/elimination of doors/windows, reconfiguration or extension of systems, or new equipment where the work area is equal to or less than 50% of the building — Chapters 7 and 8 apply (§603.1, §603.2, §801.1, §801.2).
  • Level 3 = work area exceeds 50% of building area — Chapters 7, 8 and 9 apply (§604.1, §604.2, §901.1, §901.2).

Decision‑relevant table

Decision dimension Level 1 value Level 2 value Level 3 value Code reference
Typical scope Removal/replacement or covering using like materials (no space reconfiguration) Space reconfiguration and/or addition/extension of systems; work area ≤ 50% of building Extensive reconfiguration; work area > 50% of building §602.1; §603.1; §604.1
Controlling chapter(s) Chapter 7 Chapters 7 and 8 Chapters 7, 8 and 9 §701.1; §801.1; §901.1; §801.2; §604.2
Work‑area threshold N/A (no reconfiguration) ≤ 50% of building area > 50% of building area §602.1; §603.1; §604.1
Must also comply with Level 1 rules? n/a Yes — Chapter 7 requirements apply in addition to Chapter 8 Yes — Chapters 7 and 8 requirements apply in addition to Chapter 9 §603.2; §801.2; §604.2; §901.2
Work‑area shown on plans Required to be identified Required to be identified Required to be identified §601.2
Key cross‑discipline triggers called out (examples) New interior finishes, floor finishes, trim—must meet CBC provisions when installed Means of egress, fire‑protection, structural, electrical, mechanical, plumbing upgrades may be required within work area Same as Level 2 but may require upgrades beyond work area to improve safety elsewhere §702.x series; §802.x; §803–805; §903.x

Key specific provisions you will encounter in each chapter (illustrative)

  • Chapter 7: general scope, conformance rule (an alteration must not make a building less safe), flood hazard note, and building‑element specifics such as interior finishes and floor finishes (§701.1, §701.2, §701.3, §702.1–§702.4).
  • Chapter 8: general scope for Level 2, requirement that Chapter 7 also applies, system‑installation exceptions (when Level 2 building element triggers are not applicable), and requirements for means of egress, fire protection, structural, electrical and mechanical work within the work area (§801.1–§801.4; §§802–807).
  • Chapter 9: general scope for Level 3, requirement that Chapters 7 and 8 also apply, and provisions that may require improvements beyond the work area (examples include shaft enclosures, smoke compartments and separations in certain occupancies) (§901.1–§901.2; §§902–903).

Exceptions & special cases

  • Movable/nonfixed fixtures (counters, racks, cases, partitions under 5 ft 9 in) are not considered Level 2—even if they change layout—so they do not alone trigger Chapter 8 (§603.1 exception).
  • Reconfiguration that is exclusively to meet accessibility requirements (Section 306.7.1) may permit compliance under Chapter 7 instead of Chapter 8 (§801.1 exception and §901.2 exception where applicable).
  • Some work types are explicitly limited in Chapter 8 system rules: if Level 2 work is limited solely to mechanical, electrical, fire‑protection, hazardous‑material abatement, windows/hardware/outlets/signs, or accessibility work, certain Chapter 8 work‑area requirements do not apply (§801.3).
  • Historic buildings are handled under the California Historical Building Code (Part 8, Title 24), not Chapters 7–9 (see §701.1 note and §607 in Chapter 6).

If a particular technical trigger (eg, shaft enclosures, smoke compartments, sprinkler extensions, structural upgrades) is relevant, look up the specific section in the applicable chapter (Chapters 7, 8 or 9) because those chapters contain topic‑by‑topic technical prescriptions (see chapter tables of contents: e.g., Chapter 7 sections 702–708; Chapter 8 sections 802–809; Chapter 9 sections 902–905).

Common mistakes

  • Misclassifying the level by failing to calculate the work area correctly (CEBC requires the work area be identified on the construction documents — §601.2).
  • Assuming Level 2 or 3 rules replace Level 1 rules — in fact, Level 2 must comply with Chapter 7 as well as Chapter 8 (§603.2 and §801.2); Level 3 must comply with Chapters 7 and 8 in addition to Chapter 9 (§604.2 and §901.2).
  • Treating temporary or movable fixtures (counters, racks, partitions under 5 ft 9 in) as Level 2 triggers; they are excluded by the §603.1 exception.
  • Omitting required cross‑discipline checks (means of egress, fire protection, structural, energy) that Chapters 7–9 require for work areas — the chapters are intentionally cross‑referenced to cover building systems (see Chapter 8 and Chapter 9 chapter descriptions and section lists).

Worked example — concrete scenario

Scenario: A 10,000 sq ft one‑story office building. The owner plans to remove existing partitions and reconfigure the interior of multiple tenant spaces totaling 4,500 sq ft (all on the single floor). New interior partitions, two new operable windows, and extension of mechanical ductwork and electrical circuits are included.

Step 1 — classify by work area:

  • Work area = 4,500 sq ft ÷ building area 10,000 sq ft = 45% → this is ≤ 50% so the work is Level 2 per §603.1.

Step 2 — determine which chapters apply:

  • Level 2 work must comply with Chapter 7 (Level 1 rules) and Chapter 8 (Level 2 rules) (§603.2, §801.2). So the design must verify Chapter 7 items (e.g., interior finishes rules at §702.x) and Chapter 8 items for egress/fire/structural/equipment (§802–§805).

Step 3 — check exceptions:

  • If the partition changes were only movable partitions under 5 ft 9 in, they might not be Level 2. But here partitions are full height reconfiguration so Chapter 8 applies (§603.1 exception clarifies the cutoff).

Step 4 — documentation:

  • Identify the 4,500 sq ft work area and show it on the construction documents as required by §601.2. Provide compliance narrative showing which Chapter 7 and Chapter 8 provisions are met, and call out any required upgrades to egress or fire protection found in Chapter 8.

If instead the same project had been 6,000 sq ft of reconfiguration (60% of the building), it would be Level 3 and Chapters 7, 8 and 9 would apply; additional requirements in Chapter 9 might require upgrades beyond the immediate work area (see §604.2 and §901.2).

Related provisions

  • Classification and definitions for Level 1, 2 and 3: §602, §603, §604 (Chapter 6)
  • Work‑area identification requirement: §601.2 (Chapter 6)
  • Chapter 7 general scope and conformance: §701.1, §701.2, §701.3 (Chapter 7)
  • Chapter 7 building elements: §702 (interior finishes, floor finishes, trim) (Chapter 7)
  • Chapter 8 general, system exceptions, and cross‑discipline triggers: §801.1–§801.4 and §§802–807 (Chapter 8)
  • Chapter 9 general scope and requirements that may extend beyond work area: §901.1–§901.2 and §§902–903 (Chapter 9)

Code references

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

  • CBC § 1.10.1 High relevance — show source text

    Chapter 5A Prescriptive Compliance Method.

    Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).

    Chapter 6 Classification of Work.

    Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.

    Chapter 7 Alterations—Level 1.

    Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.

    Chapter 8 Alterations—Level 2.

    A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.

    Chapter 9 Alterations—Level 3.

    Chapter 9 provides the technical requirements for those existing buildings that undergo Level 3 alterations. Level 3 alterations are those involving alterations that cover 50 percent of the aggregate area of the building. Under certain situations, this chapter also intends to improve the safety of certain building features beyond the work area and in other parts of the building where no alteration work might be taking place.

    Chapter 10 Change of Occupancy.

    The purpose of Chapter 10 is to address existing buildings that are subject to a change of occupancy. This chapter is an assembly of requirements to upgrade safety without having to comply fully as a new building. A change of occupancy classification is considered a change of occupancy, however, it will involve a higher level of regulation since the use of the building has made a more significant change.

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    Chapter 11 Additions.

    Chapter 11 provides the requirements for additions, which are considered new construction. The requirements focus on safely integrating the addition with the existing building. This includes issues such as limiting the overall height and area of the building where the addition is not separated by a fire wall.

    Chapter 12 Historic Buildings —Reserved

    Chapter 12 is not adopted by the State of California. Historic buildings and structures shall comply with Part 8, Title 24, California Code of Regulations.

    Chapter 13 Performance Compliance Methods.

    Chapter 13 allows for existing buildings to be evaluated to show that alterations or a change of occupancy, while not meeting new construction requirements, will provide a level of safety to demonstrate compliance. Provisions are based on a numerical scoring system involving 21 safety parameters where, when evaluated, such buildings must meet a minimum overall safety score.

  • CBC § 2.2 High 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.

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    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:

    1. The window is operable.
    2. One of the following applies: 2.1.
  • CBC § 701.1 High relevance — show source text
    Adopting Agency BSC BSC-
    CG    		 SFM 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-
    CG    		 SFM 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 below
    Chapter / 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.

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    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

  • CBC § 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.)

  • CBC § 1.11. High relevance — show source text

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

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    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:

    1. Mechanical systems, electrical systems, fire protection systems and abatement of hazardous materials.
    2. Windows, hardware, operating controls, electrical outlets and signs.
    3. 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:

    1. Where windows are added they are not required to comply with the light and ventilation requirements of the California Building Code .

    2. Newly installed electrical equipment shall comply with the requirements of Section 806.

    3. The length of dead-end corridors in newly constructed spaces shall only be required to comply with the provisions of Section 804.8.

    4. The minimum ceiling height of the newly created habitable and occupiable spaces and corridors shall be 7 feet (2134 mm).

    5. 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).

    6. 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.

  • CBC § 604.1 High relevance — show source text

    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.)

    Adopting Agency BSC BSC-
    CG    		 SFM 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-
    CG    		 SFM 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 below
    Chapter / Section
    701.1 X
    702.7 X
    703.2 X
    703.2.1 X
    _703.2.
  • CBC § 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.

  • CBC § 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 .

  • CBC § 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.

    2025 CALIFORNIA EXISTING BUILDING CODE 8-1

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    8-2 2025 CALIFORNIA EXISTING BUILDING CODE

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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.

  • CBC § 601.1.1 Medium 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.

    2025 CALIFORNIA EXISTING BUILDING CODE 6-1

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    6-2 2025 CALIFORNIA EXISTING BUILDING CODE

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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

  • CBC § 901.1 Medium 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:

    1. A smoke compartment in accordance with Section 422.3 of the California Building Code, where the alteration results in an ambulatory care facility greater than 10,000 square feet on one story.
    2. Separation from adjacent spaces in accordance with Section 422.2 of the California Building Code, where any such facility has the potential for four or more care recipients 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.

  • CBC § 7-3 Medium relevance — show source text

    702 Building Elements and Materials . . . . . . . . . . . . . . . . . 7-3

    703 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4

    704 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4

    705 Reroofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4

    706 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5

    707 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6

    708 Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6

    CHAPTER 8 ALTERATIONS—LEVEL 2 . . . . . . . . . . . . . . . . . .8-3

    801 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3

    802 Building Elements and Materials . . . . . . . . . . . . . . . . . 8-3

    803 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5

    804 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5

    805 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9

    806 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10

    807 Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10

    808 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10

    809 Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10

    CHAPTER 9 ALTERATIONS—LEVEL 3 . . . . . . . . . . . . . . . . . .9-3

    901 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3

Frequently asked questions

How do I tell whether my renovation is Level 1, 2 or 3?

Check the scope definitions in Chapter 6: Level 1 is replacement/covering (no reconfiguration) (§602.1); Level 2 is reconfiguration or system extension where the work area is ≤ 50% (§603.1); Level 3 is when the work area exceeds 50% (§604.1).

If I add a few new windows, which chapter applies?

Adding windows is listed as a Level 2 activity in §603.1, so Chapter 7 and Chapter 8 apply unless the work is limited to windows only and an exception applies per §801.3.

Do Level 2 or 3 rules replace Level 1 rules?

No. Level 2 work must also comply with Chapter 7 (Level 1) (§603.2, §801.2). Level 3 work must comply with Chapters 7 and 8 in addition to Chapter 9 (§604.2, §901.2).

Are movable displays and low partitions counted toward the work area?

Movable or nonfixed fixtures, cases, racks, counters and partitions not over 5 ft 9 in (1753 mm) high are not considered Level 2 work under the §603.1 exception.

What must I show on the plans to support the classification?

You must identify the work area on the construction documents (see §601.2) and document applicable Chapters/sections you are complying with (Chapters 7–9 as applicable).

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