CEBC · California Existing Building Code
Alteration Level 3 and additions — extensive reconfiguration and integration
If your renovation changes more than half of the building (work area >50%), it’s a Level 3 alteration and must follow Chapters 7, 8 and 9 of the CEBC (see **§ 604.1** and **§ 901.1**). Additions are treated as new construction and Chapter 11 governs how the addition integrates with the existing building (see **§ 606.1**). I could not retrieve the exact text of **§ 1101** from the files you provided — please supply Chapter 11 / § 1101 if you want a line-by-line interpretation.
Last reviewed: July 6, 2026
The single most important rule: If the work area exceeds 50% of the building area, the project is a Level 3 alteration and must follow the Level 3 chapter plus the Level 1 and 2 requirements. § 604.1.
What the code requires — 2–4 sentences
Level 3 alterations apply where the work area exceeds 50 percent of the building area — § 604.1. Level 3 work must comply with Chapter 9 (Level 3) requirements and, in addition, the requirements for Level 1 and Level 2 alterations in Chapters 7 and 8 (see § 901.1). Additions are treated as new construction and must comply with Chapter 11; the CEBC frames Chapter 11 as focusing on safe integration of the addition with the existing building (see § 606.1 and Chapter 11 overview).
Requirements in detail
Scope and when Level 3 applies
- Defined threshold: work area > 50% of building area → Level 3 (scope: § 604.1).
- Level 3 projects must meet Level 1 (Chapter 7) and Level 2 (Chapter 8) provisions in addition to Chapter 9 (see § 604.2 and § 901.1).
How additions are treated
- Additions are considered new construction and Chapter 11 contains the requirements to integrate an addition safely with the existing building. The CEBC explicitly points to Chapter 11 for additions (scope: § 606.1).
- Chapter 11 emphasizes limits on overall height and area where the addition is not separated from the existing building by a firewall (overview in Chapter 11 description).
Additional mandatory upgrades triggered by Level 3 work
- Where Level 3 work affects means of egress, fire protection, or structural systems, Chapter 9 may require upgrades beyond the work area (see § 901.2 and Chapter 9 user notes).
- Existing stairways that are part of the means of egress must be enclosed from the highest work-area floor to exit discharge and all floors below (see § 903.1).
- The requirements of selected sections from Chapters 7 and 8 — for example, building elements, fire protection, and egress — apply within all Level 3 work areas even if shared with other tenants (see § 901.2).
Decision-relevant dimensions, thresholds and references
| Decision dimension / question | Key value or action | What it controls | Code Reference |
|---|---|---|---|
| Work-area threshold for Level 3 | > 50% of building area | Classifies project as Alteration — Level 3 | § 604.1 |
| Required chapters for Level 3 work | Chapters 7, 8 and 9 | All applicable Level 1 & 2 provisions plus Level 3 rules | § 604.2; § 901.1 |
| Additions classification | Additions = new construction (integrate with existing) | Follow Chapter 11 integration requirements | § 606.1; Chapter 11 overview |
| Egress / shared exits in work area | Applies regardless of occupant load | Sections 802, 803, 804, 805 apply inside work areas | § 901.2 |
| Stairway enclosure requirement | Enclose stairways from highest work-area floor to exit discharge | Protects vertical egress routes | § 903.1 |
| Accessibility-only reconfiguration | If reconfiguration affects exits/shared egress solely to meet accessibility § 306.7.1 | May be excepted from Chapter 9 | § 901.2 exception |
(Every bolded term above is a defined/code-critical term in the CEBC on first mention.)
Compliance flow (practical checklist)
- Measure and mark the work area on the drawings (the CEBC requires the work area to be identified; see Chapter 6 general provisions).
- If the work area is >50%, apply Chapter 9 plus Chapters 7 and 8 requirements (§ 604.1, § 901.1).
- Identify egress and shared-corridor impacts — Sections 802–805 must be checked for the work area (§ 901.2).
- For any addition, treat the addition as new construction and follow Chapter 11 integration rules (CEBC Chapter 11 overview; § 606.1). If you need the exact text of § 1101, see “Missing retrieval” below.
Exceptions & special cases
- Accessibility-only reconfiguration: Buildings where reconfiguration of space affecting exits/shared egress is done exclusively to meet accessibility § 306.7.1 may be excepted from Chapter 9 (see the exception to § 901.2).
- Chapter adoption differences: Some CEBC sections are not adopted by every state agency (matrix notes). Verify adopted/amended status with your local authority; the CEBC includes a matrix that shows adoption differences.
- Additions that exceed certain size thresholds may trigger different seismic retrofit evaluation entries (see seismic provisions and Table references in Chapter 3A / Section 317 notes). These are cross-referenced in the CEBC; review Section 317 for seismic evaluation triggers.
Important note about Section 1101: the user requested Section § 1101 as a controlling citation. I could retrieve the CEBC Chapter 11 overview and the CEBC statement that additions are treated as new construction (see § 606.1 and Chapter 11 description), but the specific text of § 1101 (the first section inside Chapter 11) was not available in the files you provided. I cannot invent or paraphrase a section I did not retrieve; please supply the file containing § 1101 or consult Chapter 11 directly for the precise 1101 language.
Common mistakes
- Failing to calculate the work area correctly — designers sometimes use tenant areas rather than the CEBC-defined work-area boundaries; an incorrect work-area measure changes the entire compliance path (Level 2 vs Level 3). See Chapter 6 requirement to identify the work area.
- Treating additions as “minor” and not applying Chapter 11 integration checks — additions are explicitly treated like new construction in the CEBC (§ 606.1).
- Ignoring cross-chapter requirements: Level 3 requires applying Chapters 7 & 8 in addition to Chapter 9 — missing these overlap requirements leads to incomplete scope of work. § 901.1–901.2.
- Assuming accessibility-driven layout changes never trigger Level 3 — there is a narrow exception where reconfiguration affecting exits/shared egress done exclusively for § 306.7.1 accessibility compliance may be excepted; this is not a blanket exemption. § 901.2 exception.
Worked example — concrete scenario with numbers
Scenario: Existing office building, total area = 10,000 ft². Owner proposes a renovation that reconfigures open office and tenant spaces over 6,000 ft² and also adds a new 2,000 ft² unseparated addition connected to the existing building.
- Work-area classification:
- Work area = 6,000 ft² / 10,000 ft² = 60% → Level 3 alteration (threshold >50%, § 604.1).
- Compliance path:
- Apply Chapters 7 and 8 (Level 1 & 2) requirements plus Chapter 9 (Level 3) per § 604.2 and § 901.1.
- Egress and stairways:
- If the reconfiguration affects shared exits, ensure Sections 802–805 are satisfied in the work area (per § 901.2). Enclose existing stairways from highest work-area floor down to exit discharge if required (per § 903.1).
- Addition integration:
- The 2,000 ft² addition is treated as new construction; follow Chapter 11 integration requirements. Because the addition is connected (not separated by a firewall), Chapter 11’s guidance about limiting overall height/area and integrating fire protection applies (CEBC Chapter 11 overview; see § 606.1). For the exact Chapter 11/§ 1101 text and the specific new-construction limits/criteria, the precise § 1101 language must be consulted (not retrieved here).
- Seismic/structural consequences:
- Because the project involves a significant alteration plus an addition, consult the CEBC seismic evaluation triggers (e.g., Section 317 notes and Table 317.5) to see whether a seismic evaluation or retrofit is required.
Related provisions
- § 604.1 — Alteration—Level 3 scope (work-area >50%).
- § 604.2 — Level 3 application: must comply with Chapters 7 and 8 as well.
- § 901.1 — Chapter 9 general (Level 3 compliance).
- § 901.2 — Chapter 9 compliance details and exceptions (802–805 applicability; accessibility exception).
- § 903.1 — Existing shafts and vertical openings (stairway enclosure requirement).
- § 606.1 — Additions scope (Chapter 11 applies).
- Chapter 11 overview / additions treated as new construction (integration, height/area limits).
- Chapter 6 — Work-area identification and classification (general rules for determining Level 1/2/3).
- Section 317 and Table 317.5 — seismic performance / evaluation triggers relevant to additions and substantial work.
Code references
Grounded in the retrieved California Existing Building Code — click a citation to read the verbatim passage:
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
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 § 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.
California Existing Building Code High relevance — show source text
|100 psf|1 hr
23 min|||7|1, 2|11/3| |F/C-4-RC-9|4″|4″ deep (4370 psi);1/4″ reinforcement bars
at 6″ pitch with3/4″ cover;1/4″ main rein-
forcement bars at 4″ pitch perpendicular
with1/2″ cover; 13′1″ span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-10|4″|4″ thick (5140 psi) deck;1/4″ reinforce-
ment bars at 71/2″ pitch with7/8″ cover;3/8″
main reinforcement bars at 33/4″ pitch
perpendicular with1/2″ cover; 13′1″ span
restrained.|140 psf|1 hr
16 min|||7|1, 5|11/4| |F/C-4-RC-11|4″|4″ thick (4000 psi) concrete deck;
3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
with top surface; 4″ × 6″ x 13 SWG mesh
reinforcement 1″ from bottom of slab; 6′6″
span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-12|4″|4″ deep (2380 psi) concrete deck;
3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
with top surface; 4″ × 6″ x 13 SWG mesh
reinforcement 1″ from bottom surface;
6′6″ span restrained.|150 psf|1 hr
3 min|||7|1, 2|1| |F/C-4-RC-13|41/2″|41/2″ thick (5200 psi) deck;1/4″ reinforce-
ment bars at 71/4″ pitch with7/8″ cover;3/8″
main reinforcement bars at 33/4″ pitch
perpendicular with1/2″ cover; 13′1″ span
restrained.|140 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-14|41/2″|41/2″ deep (2525 psi) concrete deck;1/4″
reinforcement bars at 71/2″ pitch with7/8″
cover;3/8″ main reinforcement bars at
33/8″ pitch perpendicular with1/2″ cover;
13′1″ span restrained.|150 psf|42 min|||7|1, 5|2/3| |F/C-4-RC-15|41/2″|41/2″ deep (4830 psi) concrete deck;
11/2″ × No.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.
CBC § 301 High relevance — show source text
The IEBC is a model code in the International Code family of codes intended to provide requirements for repair and alternative approaches for alterations, changes of occupancy and additions to existing buildings. A large number of existing buildings and structures do not comply with the current building code requirements for new construction. Although many of these buildings are potentially salvageable, rehabilitation is often cost-prohibitive because compliance with all the requirements for new construction could require extensive changes that go well beyond the value of the building or the original scope of the alteration. At the same time, it is necessary to regulate construction in existing buildings that undergo additions, alterations, extensive repairs or change of occupancy. Such activity represents an opportunity to ensure that new construction complies with the current building codes and that existing conditions are maintained, at a minimum, to their current level of compliance or are improved as required to meet basic safety levels. To accomplish this objective, and to make the alteration process easier, this code allows for options for controlled departure from full compliance with the International Codes dealing with new construction, while maintaining basic levels for fire safety, structural and life safety features of the rehabilitated building.
This code provides three main options for a designer in dealing with alterations of existing buildings. These are laid out in Section 301 of this code:
Option 1: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Prescriptive Compliance Method given in Chapter 5. It should be noted that this method originates from the former Chapter 34 of the IBC (2012 and earlier editions).
Option 2: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Work Area Compliance Method given in Chapters 6 through 12.
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Option 3: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Performance Compliance Method given in Chapter 13. It should be noted that this option was also provided in the former Chapter 34 of the IBC (2012 and earlier editions).
Under limited circumstances, a building alteration can be made to comply with the laws under which the building was originally built, as long as the accessibility requirements are met, there has been no substantial structural damage and there will be limited structural alteration. Flood hazard provisions also must still be addressed where there is a substantial improvement.
Note that all repairs must comply with Chapter 4 and all relocated buildings are addressed by Chapter 14.
ARRANGEMENT AND FORMAT OF THE 2025 CEBC
The format of the CEBC allows each chapter to be devoted to a particular subject. The following table shows how the CEBC is divided. The subsequent table shows CEBC requirements that are correlated with other California Codes. The chapter synopses detail the scope and intent of the provisions of the CEBC.
CEBC § 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-
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. CRC § 301 High relevance — show source text
This change expands the current process from two independent 1-year cycles to a single continuous 3year cycle. There will be two groups of code development committees and they will meet in separate years. The current groups will be reworked. With the energy provisions of the International Energy Conservation Code ® (IECC®) and Chapter 11 of the International Residential Code ® (IRC®) now moved to the Code Council’s Standards Development Process, the reduced volume of code changes will be distributed between Groups A and B.
Code change proposals submitted for code sections that have a letter designation in front of them will be heard by the respective committee responsible for such code sections. Because different committees hold Committee Action Hearings in different years, proposals for most codes will be heard by committees in both the 2024 (Group A) and the 2025 (Group B) code development cycles. It is very important that anyone submitting code change proposals understands which code development committee is responsible for the section of the code that is the subject of the code change proposal.
Please visit the ICC website at iccsafe.org/products-and-services/i-codes/code-development/current-code-development-cycle for further information on the Code Development Committee responsibilities as it becomes available.
Coordination of the I-Codes
The coordination of technical provisions allows the I-Codes to be used as a complete set of complementary documents. Individual codes can also be used in subsets or as stand-alone documents. Some technical provisions that are relevant to more than one subject area are duplicated in multiple model codes.
INTRODUCTION TO THE INTERNATIONAL EXISTING BUILDING CODE
The IEBC establishes minimum requirements for existing buildings using prescriptive and performance-related provisions. It is founded on broad-based principles intended to encourage the use and reuse of existing buildings while requiring reasonable upgrades and improvements.
The IEBC is a model code in the International Code family of codes intended to provide requirements for repair and alternative approaches for alterations, changes of occupancy and additions to existing buildings. A large number of existing buildings and structures do not comply with the current building code requirements for new construction. Although many of these buildings are potentially salvageable, rehabilitation is often cost-prohibitive because compliance with all the requirements for new construction could require extensive changes that go well beyond the value of the building or the original scope of the alteration. At the same time, it is necessary to regulate construction in existing buildings that undergo additions, alterations, extensive repairs or change of occupancy. Such activity represents an opportunity to ensure that new construction complies with the current building codes and that existing conditions are maintained, at a minimum, to their current level of compliance or are improved as required to meet basic safety levels. To accomplish this objective, and to make the alteration process easier, this code allows for options for controlled departure from full compliance with the International Codes dealing with new construction, while maintaining basic levels for fire safety, structural and life safety features of the rehabilitated building.
This code provides three main options for a designer in dealing with alterations of existing buildings. These are laid out in Section 301 of this code:
Option 1: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Prescriptive Compliance Method given in Chapter 5. It should be noted that this method originates from the former Chapter 34 of the IBC (2012 and earlier editions).
Option 2: Work for alteration, change of occupancy or addition of all existing buildings shall be done in accordance with the Work Area C
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 § 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 § 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 § 501A.3 Medium relevance — show source text
501 A .2 Fire-resistance ratings. Fire-resistance ratings shall comply with the California Building Standards Code.
501A.3 Prescriptive compliance provisions. Alterations, additions and changes of occupancy to the following categories of existing buildings and structures shall comply with the provisions of this section.
501A.3.1 Prescriptive compliance provisions for SPC-4D using the California Building Code, 1980 (CBC 1980). Nonconforming buildings shall satisfy the following requirements: 1. The California Building Code, 1980 (CBC 1980), as used in this chapter, consists of the Uniform Building Code, 1979 (UBC 1979) along with requirements contained in: a) California Code of Regulations, Title 24- Building Standards, dated February 2, 1980 (Revision record for Register 80, No. 5). b) California Code of Regulations, Title 22 – Social Security, dated October 13, 1979 (Revision Record for Register 79, No 41). c) California Code of Regulations, Title 17 – Public Health, dated October 13, 1979 (Revision Record for Register 79, No 41-B). 2. All existing structural elements of Seismic Force Resisting System (SFRS) shall satisfy the detailing requirements in the CBC 1980 or demonstrate that the level of seismic performance is equivalent to that given in the CBC 1980, as determined by the building official. 3. A continuous load path or paths with adequate strength and stiffness to transfer all the forces from the point of origin to final point of resistance shall be justified by analysis. 4. Site data report in accordance with the CBC 1980 shall establish that seismically induced differential settlement does not exceed 1 ″ in 40 ′ .
5. Adjacent buildings shall satisfy the SPC building separation requirements in accordance with the California Administrative Code, Chapter 6 Section 3.4. 6. The addition of new structural elements or strengthening of existing structural elements for retrofit of nonconforming build- ings to SPC-4D shall comply with the following: a) The seismic demand (forces or displacements) shall be in accordance with the CBC 1980; b) Capacity, detailing and connections for new structural elements shall satisfy the requirements in the CBC 2025 for new construction; and c) The strengthening of existing structural elements shall use capacities determined in accordance with the CBC 2025 for new construction consistent with the detailing and connections used in the strengthened member. 7. All construction, quality assurance and quality control shall be in accordance with the new construction provisions of CBC 2025.
8. Elements not part of the Seismic Force-Resisting System (SFRS), including those identified in the California Administrative Code Chapter 6, Article 10, shall be evaluated using seismic forces and the requirements of the CBC 1980. 9. Any column or wall that forms part of two or more intersecting SFRS and is subjected to axial load due to seismic forces acting along either principal plan axis equaling or exceeding 20 percent of the axial design strength of the column or wall shall be _evaluated for the most critical load effect due to application of seismic force in any direction.
Frequently asked questions
Does any reconfiguration that touches 50% count as Level 3?
Yes — projects where the work area exceeds 50% of the building area are Level 3 under § 604.1. If the work area is exactly 50%, the project is typically a Level 2; Level 3 is for work that exceeds that 50% threshold.
Are additions always required to follow new-construction rules?
Additions are treated as new construction for integration purposes and Chapter 11 applies per § 606.1, but the CEBC frames Chapter 11 to focus on integrating the addition with the existing building rather than wholesale new-building compliance. For the specific Chapter 11 provisions (including § 1101), consult Chapter 11 text.
If I only move lightweight partitions in most of the building, is that Level 3?
If the moved/added partitions are nonfixed or under 5 ft 9 in (1753 mm) in height, they may be excluded from Level 2 counting; however, Level 3 depends on the work-area percentage and the nature of the work. Check the exception language for Level 2 and confirm the work-area calculation in Chapter 6.
Do stairways have to be enclosed for Level 3 projects?
Existing stairways that are part of means of egress must be enclosed from the highest work-area floor to exit discharge and floors below where required by Chapter 9 (see § 903.1).
Where can I find the exact requirements for § 1101?
The specific text of § 1101 was not available in the documents provided to me; I retrieved Chapter 11 overview that explains additions are considered new construction and references integration topics, but I could not retrieve the exact § 1101 wording. Please provide Chapter 11/§ 1101 or consult the CEBC Chapter 11 in your copy for the precise text.
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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