CEBC · California Existing Building Code

What makes an alteration Level 3 and what special occupancy rules apply (R-2.1, ambulatory care)?

If your renovation affects more than half the building by area, it is a Level 3 alteration under the CEBC and Chapter 9 requirements apply; if that Level 3 area contains Group R‑2.1 sleeping spaces or an ambulatory care facility that is enlarged above **10,000 sq ft** on one story or could have **4 or more** care recipients unable to self‑preserve, the CEBC requires added smoke compartmentation and separations as specified in **§ 902.2**, **§ 902.2.1**, and **§ 902.3**.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

An alteration is classified as Level 3 when the work area exceeds 50 percent of the aggregate building area — see § 604.1. Level 3 work must follow Chapter 9 plus the requirements of Chapters 7 and 8; the general Chapter 9 scope and compliance requirements are stated in § 901.1 and § 901.2. For special occupancies, Group R‑2.1 classification and smoke‑barrier triggers for sleeping care recipients are set out in § 902.2 and § 902.2.1, and specific rules for ambulatory care facilities in a Level 3 work area are in § 902.3.

The single most important rule: If your alteration work area is more than 50% of the building area, you are in Level 3 and must apply the Chapter 9 requirements — and if that Level 3 work area includes an ambulatory care facility over 10,000 sq ft on one story or has the potential for 4 or more care recipients incapable of self‑preservation, additional smoke compartments or separations are required.

Requirements in detail

Quick decision table

Decision dimension Key value or threshold What that triggers Code reference
Work area size (work area ÷ aggregate building area) > 50% Alteration is Level 3; Chapter 9 applies in addition to Chapters 7 & 8 § 604.1; see Chapter 9 scope § 901.1
Applicability of Chapter 9 Level 3 alterations (work area >50%) Must comply with Chapter 9 requirements plus Chapters 7 & 8; Sections 802–805 apply within work areas § 901.1, § 901.2
Group classification for R‑2.1 Group R‑2.1 Occupancy classification follows CBC Section 308.2 (per CEBC § 902.2) § 902.2
Smoke barriers in R‑2.1 Story used for sleeping rooms for more than 30 care recipients Story must be divided into ≥ two smoke compartments (smoke barrier walls per CBC § 420.6) § 902.2.1
Ambulatory care — size trigger Ambulatory care > 10,000 sq ft on one story (as a result of the alteration) Provide a smoke compartment per CBC § 422.3 § 902.3(1)
Ambulatory care — patient‑capability trigger Potential for 4 or more care recipients incapable of self‑preservation Provide separation from adjacent spaces per CBC § 422.2 § 902.3(2)

(First mention of thresholds and controlling sections is bolded above; see the cited CEBC sections for exact language.)

How the pieces fit together (step logic)

  • Step 1 — Determine work area percentage: calculate the total area where alteration work will occur and divide by the building’s aggregate area. If > 50%, you are in Level 3 and must apply Chapter 9 requirements in addition to Chapters 7 and 8 (§ 604.1, § 901.1, § 901.2).
  • Step 2 — Identify occupancies inside the Level 3 work area: if there are Group R‑2.1 spaces, classify them per CBC § 308.2 as required by § 902.2. If the work area is on a story used for sleeping rooms for more than 30 care recipients, add smoke barriers to create at least two compartments per § 902.2.1.
  • Step 3 — If the Level 3 area includes an ambulatory care facility, check the two special triggers in § 902.3: size (> 10,000 sq ft on one story) and patient capability (4 or more incapable of self‑preservation) — each trigger compels specific smoke/s separation measures indicated in § 902.3(1) and § 902.3(2).

What “ambulatory care facility” triggers mean in practice

  • Smoke compartment requirement (when alteration produces ambulatory care > 10,000 sq ft on a single story) — design and location of the compartment must comply with CBC § 422.3 as referenced in § 902.3(1).
  • Separation from adjacent spaces (where 4+ care recipients unable to self‑preserve are possible) — provide the separation specified in CBC § 422.2 as called out by § 902.3(2).

Exceptions & special cases

  • Exception to Chapter 9 application: where space reconfiguration affecting exits or shared egress access is done exclusively to meet accessibility requirements of § 306.7.1, the project is not required to comply with Chapter 9. See § 901.2.
  • Group R‑2.1 classification: CEBC directs you to the California Building Code for specific occupancy classification rules — CEBC § 902.2 references CBC § 308.2 for that purpose. This means some classification details are in the CBC rather than CEBC text.
  • The CEBC cross‑references CBC sections (e.g., CBC § 420.6, § 422.2, § 422.3) for technical design requirements; follow those CBC sections for the construction details required by CEBC § 902.2.1 and § 902.3.

Common mistakes

  • Treating a building as Level 2 because the work “feels” extensive — always compute the work area percentage (work area ÷ aggregate building area). If the result is > 50%, Chapter 9 applies; this is an objective threshold under § 604.1.
  • Overlooking the special ambulatory‑care triggers: even if the Level 3 area is small in other respects, an ambulatory care area created or enlarged to > 10,000 sq ft on one story requires a smoke compartment per § 902.3(1).
  • Forgetting patient capability: the code uses the phrase “incapable of self‑preservation.” If the facility has the potential for 4 or more such care recipients at any time, separation per § 902.3(2) is required — it’s not only about current occupants but potential.
  • Not coordinating with the referenced CBC sections: CEBC invokes CBC design criteria (smoke walls, compartmentation, separation). Designers sometimes stop at the CEBC trigger and fail to implement the CBC‑level details that CEBC requires.

Worked example — concrete scenario

Scenario facts:

  • Existing building aggregate area = 20,000 sq ft.
  • The owner proposes renovation work that will be performed in a contiguous work area of 11,000 sq ft (the area of alteration).
  • The work area includes an existing ambulatory care clinic that, after reconfiguration, will occupy 12,000 sq ft on a single story.
  • The clinic regularly serves patients some of whom may be incapable of self‑preservation, and at peak times 5 such patients could be present.

Steped application:

  1. Compute work area percentage: 11,000 ÷ 20,000 = 0.55 = 55% → > 50%, so this is a Level 3 alteration. Apply Chapter 9 plus Chapters 7 and 8 as required by § 604.1 and § 901.1/§ 901.2.
  2. Ambulatory care checks under § 902.3: the altered ambulatory care area becomes 12,000 sq ft on one story, which is > 10,000 sq ft, so a smoke compartment per CBC § 422.3 is required (CEBC § 902.3(1)).
  3. Patient‑capability check: the clinic has the potential for 5 care recipients incapable of self‑preservation (≥ 4), so separation from adjacent spaces per CBC § 422.2 is required under CEBC § 902.3(2).

Resulting requirements to carry into the design permit set:

  • Full Chapter 9 scope and the applicable Chapters 7 & 8 upgrades.
  • Design and provide smoke compartmentation per CBC § 422.3 for the ambulatory care area.
  • Provide the required separation from adjacent spaces per CBC § 422.2 because of the 4+ incapable‑of‑self‑preservation trigger.

Related provisions (CEBC sections to review)

  • § 604.1 — Definition and scope of Alteration — Level 3 (work area > 50%).
  • § 901.1 — Chapter 9 scope (Level 3 alterations).
  • § 901.2 — Compliance rules; applicability of Sections 802–805 in work areas and the accessibility exception (§ 306.7.1).
  • § 902.2 — Group R‑2.1 occupancy classification direction (reference to CBC § 308.2).
  • § 902.2.1 — Smoke barrier compartmentation trigger for R‑2.1 where sleeping rooms serve more than 30 care recipients.
  • § 902.3 — Ambulatory care facility triggers (> 10,000 sq ft on one story; 4 or more care recipients incapable of self‑preservation) and the required measures.
  • For parallel prescriptive triggers when work exceeds 50% (other chapters): § 503.16 / § 503.17 address similar R‑2.1 and ambulatory care triggers in the Chapter 5 prescriptive method; see those sections when using Chapter 5 compliance.

If you want, I can:

  • Walk through your specific building areas and compute the work‑area percentage;
  • Map the CEBC triggers to the CBC design sections you’ll need (smoke barrier details, ratings, doors, egress) and produce a checklist for permit plan review.

Code references

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

  • CEBC § 902.1 High relevance — show source text

    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.

    903.2.1 Separation required. Where the work area is in any attached dwelling unit in Group R-3 or any multiple single-family dwelling (townhouse), walls separating the dwelling units that are not continuous from the foundation to the underside of the roof sheathing shall be constructed to provide a continuous fire separation using construction materials consistent with the existing wall or complying with the requirements for new structures. Work shall be performed on the side of the dwelling unit wall that is part of the work area.

    Exception: Where alterations or repairs do not result in the removal of wall or ceiling finishes exposing the structure, walls are not required to be continuous through concealed floor spaces.

    903.3 Interior finish. Interior finish in exits serving the work area shall comply with Section 802.4 between the highest floor on which there is a work area to the floor of exit discharge.

    903.4 Enhanced classroom acoustics. In Group E occupancies, where the work area is a Level 3 alteration, enhanced classroom acoustics shall be provided in all classrooms with a volume of 20,000 cubic feet (565 m [3] ) or less. Enhanced classroom acoustics shall comply with the reverberation time in Section 808 of ICC A117.1.

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    ALTERATIONS—LEVEL 3

    SECTION 904—FIRE PROTECTION

    904.1 Automatic sprinkler systems. An automatic sprinkler system shall be provided in accordance with Section 903 of the California Building and California Fire Codes.

  • 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:

    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.

  • CEBC § 422.3 High relevance — show source text

    503 A .16 Reserved.

    503 A .17 Ambulatory care facilities. Where a work area exceeds 50 percent of the building area and the work area includes an existing ambulatory care facility, the following shall be provided:

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

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    PRESCRIPTIVE COMPLIANCE METHOD

    503 A .18 Reserved.

    503 A .19 Reserved.

    503 A .20 Two-way communications systems. Where the work area for alterations exceeds 50 percent of the building area and the building has elevator service, a two-way communication systems shall be provided where required by Section 1009.8 of the Califor- nia Building Code.

    SECTION 504 A

    RESERVED

    SECTION 505 A

    RESERVED

    SECTION 506 A —CHANGE OF OCCUPANCY

    506 A .1 Compliance. A change of occupancy shall not be made in any building unless that building is made to comply with the requirements of the California Building Code for the use or occupancy. Changes of occupancy in a building or portion thereof shall be such that the existing building is not less complying with the provisions of this code than the existing building or structure was prior to the change. Subject to the approval of the building official, changes of occupancy shall be permitted without complying with all of the requirements of this code for the new occupancy, provided that the new occupancy is less hazardous, based on life and fire risk, than the existing occupancy.

    Exception: The building need not be made to comply with Chapter 16 A of the California Building Code unless required by Section 506 A .5.

    506 A .1.1 Change in function . A change in function shall require compliance with all the functional requirements for new construc- tion in the California Building Code, including requirements in California Building Code Section 1224. Compliance shall be only as necessary to meet the specific provisions and is not intended to require the entire building be brought into compliance.

    Exception: Minimum room clearances, areas and dimensions may meet the requirements of the 2001 California Building Code for existing rooms re-used for a similar purpose, subject to the approval of OSHPD.

    506 A .2 Certificate of occupancy. A certificate of occupancy shall be issued where it has been determined that the requirements for the new occupancy classification have been met.

    506 A .3 Stairways. An existing stairway shall not be required to comply with the requirements of Section 1011 of the California Build- ing Code where the existing space and construction does not allow a reduction in pitch or slope.

  • CEBC § 503.14 High relevance — show source text

    503.14 Smoke compartments. In Group I-2 occupancies where the alteration is on a story used for sleeping rooms for more than 30 care recipients, the story shall be divided into not less than two compartments by smoke barrier walls in accordance with Section 407.5 of the California Building Code as required for new construction.

    503.15 Refuge areas. Where alterations affect the configuration of an area utilized as a refuge area, the capacity of the refuge area shall not be reduced below the required capacity of the refuge area for horizontal exits in accordance with Section 1026.4 of the Cali- fornia Building Code .

    Where the horizontal exit also forms a smoke compartment, the capacity of the refuge area for Group I-2 and I-3 occupancies and ambulatory care facilities shall not be reduced below that required in Sections 407.5.3, 408.6.2, 420.6.1 and 422.3.2 of the California Building Code, as applicable.

    503.16 Group R-2.1 occupancies. Group R-2.1 occupancies that are being altered and where the work area is greater than 50 percent of the aggregate building area shall be classified in accordance with Section 310.3.1 of the California Building Code .

    503.16.1 Smoke Barriers in Group R-2.1 , Condition 2. 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 less than two compartments by smoke barrier walls in accordance with Section 420.6 of the California Building Code .

    503.17 Ambulatory care facilities. Where a work area exceeds 50 percent of the building area and the work area includes an existing ambulatory care facility, the following shall be provided:

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

    503.18 Enhanced classroom acoustics. In Group E occupancies, where the work area exceeds 50 percent of the building area, enhanced classroom acoustics shall be provided in all classrooms with a volume of 20,000 cubic feet (565 m [3] ) or less. Enhanced classroom acoustics shall comply with the reverberation time in Section 808 of ICC A117.1.

    503.19 Locking arrangements in educational occupancies. In Group E occupancies, Group B educational occupancies and Group I4 occupancies, egress doors with locking arrangements designed to keep intruders from entering the room shall comply with Section 1010.2.8 of the California Building Code .

    503.20 Two-way communications systems. Where the work area for alterations exceeds 50 percent of the building area and the building has elevator service, a two-way communication systems shall be provided where required by Section 1009.8 of the Califor- nia Building Code .

    SECTION 504—FIRE ESCAPES (NOT ADOPTED BY HCD)

  • CEBC § 503A.4 High relevance — show source text

    503 A .13 Voluntary lateral force-resisting system alterations. Structural alterations that are intended exclusively to improve the lateral force-resisting system and are not required by other sections of this code shall not be subject to the structural requirements of Section 503 A except as described below, provided that all of the following apply:

    1. With the alteration complete, the capacity of existing structural systems to resist forces is not reduced.
    2. New structural elements are detailed and connected to existing or new structural elements as required by the selected design criteria in accordance with Section 503A.4 or 304A.3.4 of this code. Exception: New lateral force-resisting systems designed in accordance with the California Building Code are permitted to be of a type designated as “Ordinary” or “Intermediate” where ASCE 7 Table 12.2-1 states these types of systems are not permitted.
    3. Supports and attachments for nonstructural elements removed and reinstalled to facilitate the work comply with the Cali- fornia Building Code for new construction.
    4. The alterations do not create a structural irregularity as defined in ASCE 7 or make an existing structural irregularity more

    severe.

    Exception: Condition 4 need not be satisfied where the work complies with Section 304A.3.4 of this code.

    503 A .14 Smoke compartments. Shall comply with California Building Standards Code.

    503 A .15 Refuge areas. Shall comply with California Building Standards Code.

    503 A .16 Reserved.

    503 A .17 Ambulatory care facilities. Where a work area exceeds 50 percent of the building area and the work area includes an existing ambulatory care facility, the following shall be provided:

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

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    503 A .18 Reserved.

    503 A .19 Reserved.

    503 A .20 Two-way communications systems. Where the work area for alterations exceeds 50 percent of the building area and the building has elevator service, a two-way communication systems shall be provided where required by Section 1009.8 of the Califor- nia Building Code.

    SECTION 504 A

    RESERVED

    SECTION 505 A

    RESERVED

    SECTION 506 A —CHANGE OF OCCUPANCY

  • 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 § 1.8.2.1.3. High relevance — show source text

    Exceptions: 1. [HCD 2] For relocated or moved buildings and maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures in mobilehome parks or special occupancy parks as provided in Section 1.8.2.1.3. See California Code of Regulations, Title 25, Division 1, Chapters 2 and 2.2. 2. [HCD 1] Limited-density owner-built rural dwellings.

    [HCD 1] In addition to the requirements in this chapter, maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures under the authority of the Department of Housing and Community Development, as provided in Section 1.8.2.1.1, shall comply with California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1.

    501.1.1 Compliance with other methods. Alterations, additions and changes of occupancy to existing buildings and structures shall comply with the provisions of this chapter or with one of the methods provided in Section 301.3.

    501.1.2 Existing state-owned structures. [BSC] The provisions of Sections 317 through 322 establish minimum standards for earth- quake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University and the Judicial Council.

    The provisions of Sections 317 through 322 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings.

    501.2 Fire-resistance ratings. Where approved by the code official, in buildings where an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2 of the California Building Code has been added, and the building is now sprinklered throughout, the required fire-resistance ratings of building elements and materials shall be permitted to meet the requirements of the current building code. The building is required to meet the other applicable requirements of the California Building Code .

    Plans, investigation and evaluation reports, and other data shall be submitted indicating which building elements and materials the applicant is requesting the code official to review and approve for determination of applying the current building code fire-resistance ratings. Any special construction features, including fire-resistance-rated assemblies and smoke-resistive assemblies, conditions of occupancy, means of egress conditions, fire code deficiencies, approved modifications or approved alternative materials, design and methods of construction, and equipment applying to the building that impact required fire-resistance ratings shall be identified in the evaluation reports submitted.

    501.3 Health care facilities. In Group I-2 facilities, ambulatory care facilities and outpatient clinics, any altered or added portion of an existing electrical or medical gas systems shall be required to meet installation and equipment requirements in NFPA 99.

    501.4 Existing Group R occupancies. [SFM] See the California Residential Code for existing Group R-3 occupancies or Chapter 11 of the California Fire Code for all other existing Group R occupancies.

    501.5 Carbon monoxide alarms. [HCD 1, SFM] Pursuant to Health and Safety Code Section 17926, carbon monoxide detection shall be provided in all existing Group R buildings, as required in Section 915 of the California Building Code or Section R315 of the California Resi- dential Code, as applicable.

  • CEBC § 2.1 High relevance — show source text

    SECTION 302 A —GENERAL PROVISIONS

    302 A .1 Dangerous conditions. The code official shall have the authority to require the elimination of conditions deemed dangerous.

    302 A .2 Additional codes. Alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and struc- tures shall comply with the provisions for alterations, repairs, additions and changes of occupancy or relocation, respectively, in the California Fire Code, California Mechanical Code, California Plumbing Code and California Electrical Code. Where provisions of the other codes conflict with provisions of this chapter, the provisions of this chapter shall take precedence.

    302 A .2.1 Additional codes in health care. In existing Group I-2 occupancies, ambulatory health care facilities, outpatient clinics and hyperbaric facilities, alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and structures shall also comply with NFPA 99.

    302 A .3 Existing materials and equipment. Materials and equipment already in use in a building in compliance with requirements or approvals in effect at the time of their erection or installation shall be permitted to remain in use unless determined by the code official to be unsafe in accordance with California Building Code Section 116.

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    302A.3.1 Existing seismic force-resisting systems. Where the existing seismic force-resisting system is a type that can be designated ordinary or is a welded steel moment frame constructed under a permit issued prior to October 25, 1994, values of R, W0 and Cd for the existing seismic force-resisting system shall be those specified by the California Building Code for an ordinary system unless it is demonstrated that the existing system will provide performance equivalent to that of a detailed, intermediate or special system.

    302 A .4 New and replacement materials. Except as otherwise required or permitted by this code, materials and equipment permitted by the applicable code for new construction shall be used. Like materials shall be permitted for repairs and alterations, provided no hazard to life, health or property is c reated. Hazardous materials shall not be used where the code for new construction would not permit their use in buildings of similar occupancy, purpose and location.

    302 A .4.1 New structural members and connections. New structural members and connections shall comply with the detailing provisions of the California Building Code for new buildings of similar structure, purpose and location.

    Exception: Where alternative design criteria are specifically permitted.

    302 A .5 Occupancy and use. Where determining the appropriate application of the referenced sections of this code, the occupancy and use of a building shall be determined in accordance with Chapter 3 of the California Building Code .

  • 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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    members added as part of the alteration shall comply with the California Building Code . This exception shall not apply to the following:

    1. Alterations for accessibility required by the California Building Code, Chapter 11A.

    2. Alterations that constitute substantial improvement in flood hazard areas, which shall comply with Sections 503.2, 701.3 or 1303.1.3.

    3. Structural provisions of Section 304, Chapter 5 or to the structural provisions of Sections 706, 805 and 906.

    301.3.1 Prescriptive compliance. Alterations, additions and changes of occupancy complying with Chapter 5 of this code in buildings complying with the California Fire Code shall be considered in compliance with the provisions of this code.

    Exception: Hospital buildings removed from acute care service, skilled nursing facilities, intermediate-care facilities, correctional treatment centers and acute psychiatric hospitals [OSHPD 1R, 2, 4 and 5]. The provisions of adopted sections in Chapters 3 through 5 shall control the alteration, repair and change of occupancy or function of existing structures for applications listed in Section 1.10.1, 1.10.2, 1.10.4 and 1.10.5 regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD). Refer to Chapter 3A for services, systems and utilities that serve OSHPD 1 buildings.

  • CEBC § 310.4.1 High relevance — show source text

    Family Day-Care Homes that provide accommodations for 14 or fewer children, in the provider’s own home for less than 24-hours

    Adult care and child-care facilities that are within a single family home are permitted to comply with the California Residential Code

    Lodging houses with five or fewer guest rooms

    310.4.1 Residential Group R-3.1. This occupancy group may include facilities licensed by a governmental agency for a residentially based 24-hour care facility providing accommodations for six or fewer clients of any age. Clients may be classified as ambulatory, nonambulatory or bedridden. A Group R-3.1 occupancy shall meet the requirements for construction as defined for Group R-3, except as otherwise provided for in Section 435 Special Provisions For Licensed 24-Hour Care Facilities in a Group R-2.1, R-3.1 or R-4 Occu- pancy. This group may include:

    Adult residential facilities

    Congregate living health facilities

    Intermediate care facilities for the developmentally disabled habilitative

    Intermediate care facilities for the developmentally disabled nursing

    Nurseries for the full-time care of children under the age of six, but not including “infants” as defined in Chapter 2

    Residential care facilities for the elderly

    Small family homes and residential care facilities for the chronically ill

    Exception: Group Homes licensed by the Department of Social Services which provide nonmedical board, room and care for six or fewer ambulatory children or children two years of age or younger, and which do not have any nonambulatory clients shall not be subject to regulations found in Section 435.

    Pursuant to Health and Safety Code Section 13143 with respect to these exempted facilities, no city, county or public district shall adopt or enforce any requirement for the prevention of fire or for the protection of life and property against fire and panic unless the requirement would be applicable to a structure regardless of the special occupancy. Nothing shall restrict the application of state or local housing standards to such facilities if the standards are applicable to residential occupancies and are not based on the use of the structure as a facility for ambulatory children. For the purpose of this exception, ambulatory children do not include relatives of the licensee or the licensee’s spouse.

    310.4.2 Lodging houses. Owner-occupied lodging houses with five or fewer guest rooms shall be constructed in accordance with this code or the California Residential Code, provided that facilities constructed using the California Residential Code are protected by an automatic sprinkler system installed in accordance with Section 903.3.1.3 or Section R309.1.1 of the California Residential Code.

    310.5 Residential Group R-4. Residential Group R-4 occupancy shall include buildings, structures or portions thereof for more than six ambulatory clients, but not more than 16 persons, excluding staff, who reside on a 24-hour basis in a supervised residential environment and receive custodial care. The persons receiving care are capable of self-preservation. This occupancy classification may

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  • CEBC § 7.62 High relevance — show source text
    1. For occupancies in Groups R-2 and R-3, within the interior conditioned space of individual dwelling units, where the open-sided walking surface is located not more than 25 feet (7.62 meters) measured vertically to the floor or walking surface below, required guards shall not be less than 36 inches (914 mm) in height measured vertically above the adjacent walking surface. 3. For occupancies in Group R-3, and within individual dwelling units in occupancies in Group R-2, where the top of the guard serves as a handrail on the open sides of stairs, the top of the guard shall be not less than 34 inches (864 mm) and not more than 38 inches (965 mm) measured vertically from a line connecting the nosings. 4. The guard height in assembly seating areas shall comply with Section 1030.17 as applicable. 5. Along alternating tread devices and ship’s ladders, guards where the top rail serves as a handrail shall have height not less than 30 inches (762 mm) and not more than 34 inches (864 mm), measured vertically from a line connecting the leading edge of the treads. 6. In Group F occupancies where exit access stairways serve fewer than three stories and such stairways are not open to the public, and where the top of the guard also serves as a handrail, the top of the guard shall be not less than 34 inches (864 mm) and not more than 38 inches (965 mm) measured vertically from a line connecting the nosings.

    [BE] 1015.4 Opening limitations. Required guards shall not have openings that allow passage of a sphere 4 inches (102 mm) in diameter from the walking surface to the required guard height.

    Exceptions:

    1. From a height of 36 inches (914 mm) to 42 inches (1067 mm), guards shall not have openings that allow passage of a sphere 4 [3] / 8 inches (111 mm) in diameter.
    2. The triangular openings at the open sides of a stair, formed by the riser, tread and bottom rail shall not allow passage of a sphere 6 inches (152 mm) in diameter.
    3. At elevated walking surfaces for access to and use of electrical, mechanical or plumbing systems or equipment, guards shall not have openings that allow passage of a sphere 21 inches (533 mm) in diameter.
    4. In areas that are not open to the public within occupancies in Group I-3, F, H or S, and for alternating tread devices and ship’s ladders, guards shall not have openings that allow passage of a sphere 21 inches (533 mm) in diameter.
    5. In assembly seating areas, guards required at the end of aisles in accordance with Section 1030.17.4 shall not have openings that allow passage of a sphere 4 inches (102 mm) in diameter up to a height of 26 inches (660 mm). From a height of 26 inches (660 mm) to 42 inches (1067 mm) above the adjacent walking surfaces, guards shall not have openings that allow passage of a sphere 8 inches (203 mm) in diameter.
    6. Within individual dwelling units and sleeping units in Group R-2 and R-3 occupancies, guards on the open sides of stairs shall not have openings that allow passage of a sphere 4 [3] / 8 (111 mm) inches in diameter. 7. [SFM] In lifeguard towers not open to the public, guards shall not have openings which allow passage of a sphere 21 inches (533 mm) in diameter.

Frequently asked questions

When exactly do I calculate the “work area” percentage and how is “aggregate building area” defined?

Calculate the work area (the floor area where alteration work occurs) and divide by the building’s total aggregate area. The threshold > 50% is the objective trigger for Level 3 under § 604.1; see Chapter 6 definitions and Chapter 9 scope for how the CEBC treats the work area.

If I only alter one tenant space that’s large, could that alone make the whole building Level 3?

Yes — the CEBC uses the aggregate building area in the denominator. If the single tenant work area exceeds 50% of the aggregate building area, the job is a Level 3 alteration and Chapter 9 requirements apply. § 604.1 and § 901.1 establish this.

Does CEBC design the smoke‑barrier details or do I look to the CBC?

CEBC § 902.2.1 and § 902.3 identify the triggers and require compliance with specific CBC sections (e.g., CBC § 420.6, § 422.2, § 422.3) for the technical design — you must use the CBC text for the construction details.

If an ambulatory care space is exactly 10,000 sq ft after alteration, is a smoke compartment required?

CEBC § 902.3(1) requires a smoke compartment where the alteration results in an ambulatory care facility greater than 10,000 square feet on one story. Exactly 10,000 sq ft does not exceed the threshold; “greater than” is the operative phrase in the CEBC text.

What does “incapable of self‑preservation” mean for the 4‑person trigger?

The CEBC uses that phrase as the condition for applying separation per § 902.3(2). The definition and assessment of “incapable of self‑preservation” are typically informed by the CBC and referenced standards (and by operational/clinical judgment); CEBC requires separation where the potential exists for 4 or more such persons.

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Related in the CEBC

When must structural evaluation or upgrades be performed for Level 3 alterations?

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What egress, exit-sign and two-way communications provisions apply for Level 3?

Level 3 technical requirements (Chapter 9)

California Existing Building Code