CEBC · California Existing Building Code
What are the rules for vertical openings, smoke compartments and interior finish in Level 2 work areas?
For Level 2 alterations the CEBC requires most vertical openings that connect two or more floors to be protected by a **1‑hour fire‑resistance** enclosure (with limited exceptions), demands smoke‑barrier subdivision of patient‑sleeping stories with more than **30** care recipients, and requires exits/corridors serving the work area to meet the California Building Code interior finish rules — with several supplement rules that apply when the work area exceeds **50%** of the floor. All of these requirements are found in CEBC **§ 802.1**, **§ 802.2 / § 802.2.1**, **§ 802.3**, **§ 802.4**, and **§ 802.4.1** file.
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
Level 2 alterations are governed by the CEBC’s Section § 802.1 scope; the chapter requires existing vertical openings connecting two or more floors to be enclosed with assemblies having a minimum 1‑hour fire‑resistance rating (§ 802.2.1) and subjects certain floors used for patient sleeping to smoke‑compartment subdivision (§ 802.3) while requiring exits and corridors in work areas to meet California Building Code interior finish rules (§ 802.4, § 802.4.1) . Supplemental enclosure and stair requirements apply when the work area exceeds 50 percent of the floor area (§ 802.2.2 / § 802.2.3) .
The single most important rule: in Level 2 work areas, interior vertical openings that connect floors must be protected (typically by a 1‑hour enclosure) and interior exit/corridor finishes that serve the work area must comply with the Building Code — and when the work area covers more than 50% of a floor, those protections apply across the whole floor. § 802.2.1, § 802.4.1 .
Requirements in detail
Scope and applicability
- Scope (§ 802.1) — The Section applies to work areas where Level 2 alterations are being performed and, where stated, the requirements extend beyond the immediate work area .
- Defined thresholds that trigger additional, floor‑wide protections: the 50 percent of the floor‑area threshold appears repeatedly (supplemental shaft/stair/enfinish rules) — see § 802.2.2, § 802.2.3, § 802.4.1 .
Vertical openings (what you must do)
- Baseline rule: Existing interior vertical openings connecting two or more floors shall be enclosed with approved assemblies having a fire‑resistance rating of not less than 1 hour and with approved opening protectives (§ 802.2.1) .
- Permitted alternatives/exceptions in § 802.2.1:
- If the vertical opening enclosure is not required by the CBC or CFC, the 1‑hour enclosure may not be required.
- Vertical openings other than stairways may be blocked at the floor and ceiling of the work area by installing not less than 2 inches (51 mm) of solid wood or equivalent construction.
- The enclosure is not required for openings that only connect a main floor and mezzanines, or where a set of specific conditions are met (low hazard or sprinklered moderate hazard, street floor at lowest level, open/unobstructed area, combined exit capacity, and floor‑by‑floor egress capacity) — see § 802.2.1(3) for the full conditional list .
Supplemental vertical‑opening and stairway requirements (when work area > 50% of floor)
- If the work area exceeds 50% of that floor, the enclosure requirements of § 802.2 apply to vertical openings other than stairways throughout the floor (§ 802.2.2) .
- Where the work area exceeds 50%, stairways that are part of the means of egress serving the work area must be enclosed with smoke‑tight construction on the highest work area floor and all floors below (minimum requirement) — see § 802.2.3 .
Smoke compartments (Group I‑2 sleeping floors)
- In Group I‑2 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 the CBC requirements for smoke compartments (§ 802.3) — CEBC references the CBC smoke barrier provisions for details (CBC Section 407.5) .
- The CBC guidance (referenced by CEBC) sets smoke compartment maximum areas and travel distances (e.g., 22,500 ft² default max in I‑2; exceptions and larger areas allowed under conditions) — see CBC § 407.5 for the sizing and refuge requirements .
Interior finish and trim in exits and corridors
- The interior finish and trim of walls and ceilings in exits and corridors in any work area must comply with the CBC Chapter 8 requirements (i.e., flame spread, smoke development, NFPA 286 or ASTM E84/UL 723 classifications) per § 802.4; existing noncompliant materials may be treated with approved fire‑retardant coatings and tested to demonstrate compliance as allowed by the CEBC exception in § 802.4 .
- Supplemental requirement (§ 802.4.1) — If the work area on any floor exceeds 50 percent of that floor, § 802.4 applies to exits and corridors serving the work area throughout the floor (not just within the immediate work area) — exception for finishes within tenant spaces entirely outside the work area .
- For testing/classification criteria see CBC Chapter 8 (e.g., NFPA 286 acceptance criteria or ASTM E84 class limits) referenced by CEBC § 802.4 for material performance thresholds .
Decision‑relevant dimensions / values (quick reference table)
| Topic | Key value/threshold | Code Reference |
|---|---|---|
| Minimum fire‑resistance for vertical opening enclosures | 1‑hour | § 802.2.1 |
| Blocking alternative for non‑stair vertical openings | 2 inches (51 mm) solid wood or equivalent | § 802.2.1(2) |
| Work‑area floor threshold requiring supplemental protections | 50 percent of floor area | § 802.2.2, § 802.2.3, § 802.4.1 |
| Patient‑sleeping story smoke‑compartment trigger (I‑2) | More than 30 care recipients → divide into ≥ 2 compartments | § 802.3 (references CBC § 407.5) |
| Smoke‑barrier fire‑resistance (CBC) | 1‑hour (smoke barriers per CBC § 709.3) | CBC § 709 / referenced from § 802.3 |
| Interior finish performance | Comply with CBC Chapter 8 (NFPA 286 or ASTM E84 / UL 723 criteria) | § 802.4 (CBC Ch. 8) file |
Exceptions & special cases
- The CEBC expressly defers to the CBC/CFC: if the CBC or CFC do not require vertical‑opening enclosure for a particular condition, CEBC § 802.2.1 exemption applies and an enclosure may not be required .
- Vertical openings other than stairways may be temporarily or permanently blocked at the work‑area floor/ceiling with 2‑inch solid wood (or equivalent) in lieu of providing the 1‑hour enclosure (§ 802.2.1(2)) .
- For Group I‑2 smoke‑compartment sizing and refuge requirements, CEBC points to the CBC (Section 407.5) for area limits and refuge sizing — larger compartments (e.g., up to 40,000 ft²) are permitted under specific conditions in CBC § 407.5 exceptions; CEBC does not restate those numeric exceptions, so consult the CBC text cited by § 802.3 for the full criteria .
- Interior finish that is existing and noncompliant may be accepted if treated with an approved fire‑retardant coating and tested on the same or similar material to demonstrate required classification (CEBC exception under § 802.4) .
Common mistakes
- Treating the CEBC as requiring the same scope everywhere: CEBC rules apply specifically to Level 2 work areas and only extend beyond the work area where the section explicitly says so (e.g., the 50% floor rule) — see § 802.1, § 802.4.1 file.
- Assuming all vertical openings may remain unenclosed if sprinklered — some occupancies have different exceptions (e.g., Group I‑2 still generally requires 1‑hour protection; the CFC/CBC contain nuanced exceptions) — review § 802.2.1 and the referenced CBC/CFC language rather than relying on a general rule file.
- Forgetting to apply supplemental requirements across the whole floor when the work area exceeds 50% — blocking a single opening in the work area does not negate the floor‑wide requirement for enclosures, stair smoke‑tighting, and finish compliance where the threshold is met (§ 802.2.2, § 802.2.3, § 802.4.1) .
- Overlooking the CEBC exception that permits treating existing finish with a tested fire‑retardant coating — the coating must be tested on the same or a similar material and installed in accordance with the manufacturer's instructions (§ 802.4 exception) .
Worked example — concrete scenario with numbers
Scenario: A Level 2 alteration in a hospital (Group I‑2) floor where a work area reconfigures 60% of the floor. The floor contains a vertical atrium opening connecting three stories and patient sleeping rooms with a total of 40 care recipients on that story.
Apply the CEBC rules:
- Because the work area > 50% of the floor, the enclosure requirements of § 802.2 apply to vertical openings (other than stairways) throughout the floor — you cannot limit enclosure work to just the work‑area footprint; you must address all vertical openings on that floor (§ 802.2.2) .
- The baseline CEBC rule requires vertical openings connecting two or more floors to be enclosed with 1‑hour fire‑resistance assemblies with approved opening protectives (§ 802.2.1) — so the atrium/shaft will need a compliant 1‑hour enclosure or qualify under a specific exception (unlikely here because it connects three stories in a Group I‑2) .
- Because the story is a patient‑sleeping story with more than 30 care recipients, § 802.3 requires the story be divided into not fewer than two smoke compartments (see CBC § 407.5 for compartment size and refuge area calculations) — you must provide smoke barrier walls and comply with smoke compartment sizing/egress rules referenced from CBC § 407.5 file.
- Exits and corridors serving the work area must have interior finish that complies with CBC Chapter 8 (e.g., NFPA 286 acceptance or ASTM E84 class limits) — and because the work area exceeds 50%, this finish requirement applies throughout the floor to exits/corridors serving the work area (§ 802.4.1) file.
- If existing corridor wall finishes do not meet CBC Chapter 8, CEBC § 802.4 allows treating them with an approved fire‑retardant coating, provided testing on the same or similar material demonstrates compliance — document testing and coating installation per manufacturer instructions and submit for approval .
Result summary for this scenario: plan for 1‑hour enclosures (or justified exceptions), provide smoke barriers to divide the sleeping‑patient story into at least two compartments, and ensure exit/corridor finishes meet CBC Chapter 8 (or are tested/coated per § 802.4 exception). All of the above derive directly from § 802.2.1, § 802.2.2, § 802.3, and § 802.4.1 of the CEBC file.
Related provisions
- CEBC — Scope for Level 2 work areas: § 802.1
- CEBC — Supplemental shaft/floor opening enclosure when work area >50%: § 802.2.2
- CEBC — Supplemental stairway enclosure when work area >50%: § 802.2.3
- CEBC — Existing stairways to be enclosed per § 802.2.1 from highest work area floor down: § 903.1 (CEBC Section 903 reference)
- CBC — Smoke compartment sizing and refuge area requirements: CBC § 407.5 (referenced by CEBC § 802.3)
- CBC — Smoke barriers (construction, 1‑hour rating, continuity): CBC § 709 (used by CEBC when requiring smoke barriers)
- CBC — Interior wall/ceiling finish performance tests and classes (NFPA 286, ASTM E84/UL 723): CBC § 803 (referenced by CEBC § 802.4)
Code references
Grounded in the retrieved California Existing Building Code — click a citation to read the verbatim passage:
CEBC § 802.3 High relevance — show source text
Exception: Where stairway enclosure is not required by the California Building Code or the California Fire Code .
802.3 Smoke compartments. In Group I-2 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 407.5 of the California Building Code as required for new construction.
802.4 Interior finish. The interior finish and trim of walls and ceilings in exits and corridors in any work area shall comply with the requirements of the California Building Code .
Exception: Existing materials that do not comply with the requirements of the California Building Code shall be permitted to be treated with an approved fire-retardant coating in accordance with the manufacturer’s instructions to achieve the required classification. Compliance with this section shall be demonstrated by testing the fire-retardant coating on the same material and achieving the required performance. Where the same material is not available, testing on a similar material shall be permitted.
802.4.1 Supplemental interior finish requirements. Where the work area on any floor exceeds 50 percent of the floor area, Section 802.4 shall apply to the interior finish and trim in exits and corridors serving the work area throughout the floor.
Exception: Interior finish within tenant spaces that are entirely outside the work area.
802.5 Guards. The requirements of Sections 802.5.1 and 802.5.2 shall apply in all work areas.
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ALTERATIONS—LEVEL 2
802.5.1 Minimum requirement. Every portion of a floor, such as a balcony or a loading dock, that is more than 30 inches (762 mm) above the floor or grade below and is not provided with guards, or those in which the existing guards are judged to be in danger of collapsing, shall be provided with guards.
802.5.2 Design. Where there are no guards or where existing guards must be replaced, the guards shall be designed and installed in accordance with the California Building Code .
802.6 Fire-resistance ratings. Where approved by the code official, 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.
SECTION 803—FIRE PROTECTION
803.1 Scope. The requirements of this section shall be limited to work areas in which Level 2 alterations are being performed, and where specified they shall apply throughout the floor on which the work areas are located or otherwise beyond the work area.
CEBC § 7.2. High relevance — show source text
7.2. Special-purpose occupancies where necessary for manufacturing operations and direct access is provided to not fewer than one protected stairway. 7.3. Buildings protected throughout by an approved automatic sprinkler system.
Reserved.
In Group M occupancies, a minimum 30-minute enclosure shall be provided to protect all vertical openings not exceeding three stories. This enclosure, or the enclosure specified in Section 802.2.1, shall not be required in the following locations: 9.1. Openings connecting only two floor levels. 9.2. Occupancies protected throughout by an approved automatic sprinkler system.
Reserved.
Reserved.
One- and two-family dwellings.
Group S occupancies where connecting not more than two floor levels or where connecting not more than three floor levels and the structure is equipped throughout with an approved automatic sprinkler system.
Group S occupancies where vertical opening protection is not required for open parking garages and ramps.
802.2.2 Supplemental shaft and floor opening enclosure requirements. Where the work area on any floor exceeds 50 percent of that floor area, the enclosure requirements of Section 802.2 shall apply to vertical openings other than stairways throughout the floor.
Exception: Vertical openings located in tenant spaces that are entirely outside the work area.
802.2.3 Supplemental stairway enclosure requirements. Where the work area on any floor exceeds 50 percent of that floor area, stairways that are part of the means of egress serving the work area shall, at a minimum, be enclosed with smoketight construction on the highest work area floor and all floors below.
Exception: Where stairway enclosure is not required by the California Building Code or the California Fire Code .
802.3 Smoke compartments. In Group I-2 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 407.5 of the California Building Code as required for new construction.
802.4 Interior finish. The interior finish and trim of walls and ceilings in exits and corridors in any work area shall comply with the requirements of the California Building Code .
Exception: Existing materials that do not comply with the requirements of the California Building Code shall be permitted to be treated with an approved fire-retardant coating in accordance with the manufacturer’s instructions to achieve the required classification. Compliance with this section shall be demonstrated by testing the fire-retardant coating on the same material and achieving the required performance. Where the same material is not available, testing on a similar material shall be permitted.
802.4.1 Supplemental interior finish requirements. Where the work area on any floor exceeds 50 percent of the floor area, Section 802.4 shall apply to the interior finish and trim in exits and corridors serving the work area throughout the floor.
Exception: Interior finish within tenant spaces that are entirely outside the work area.
802.5 Guards. The requirements of Sections 802.5.1 and 802.5.2 shall apply in all work areas.
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ALTERATIONS—LEVEL 2
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:
- 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.
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 § 1103.3.3 High relevance — show source text
1103.3.3 Medical emergency elevator. For existing hoistways with elevator alterations, or replacements, where the elevator car dimensions do not comply with Section 3002.4.1a of the California Building Code. The elevator car dimensions and/or the clear entrance opening dimensions may be altered where it can be demonstrated to the local jurisdictional authority’s satisfaction that the proposed configuration will accommodate the designated gurney or stretcher with equivalent ease to the existing car and/or clear entrance conditions. Written documentation from the local authority shall be provided to the California Occupational Safety and Health Elevator Unit.
1103.4 Vertical openings. Interior vertical openings, including but not limited to stairways, elevator hoistways, service and utility shafts, that connect two or more stories of a building shall be enclosed or protected as specified in Sections 1103.4.1 through 1103.4.10.
1103.4.1 Group I-2 and I-3 occupancies. In Group I-2 and I-3 occupancies, interior vertical openings connecting two or more stories shall be protected with 1-hour fire-resistance-rated construction.
Exceptions:
- In Group I-2, unenclosed vertical openings not exceeding two connected stories and not concealed within the building construction shall be permitted as follows: 1.1. The unenclosed vertical openings shall be separated from other unenclosed vertical openings serving other floors by a smoke barrier. 1.2. The unenclosed vertical openings shall be separated from corridors by smoke partitions. 1.3. The unenclosed vertical openings shall be separated from other fire or smoke compartments on the same floors by a smoke barrier. 1.4. On other than the lowest level, the unenclosed vertical openings shall not serve as a required means of
egress. 2. In Group I-2, atriums connecting three or more stories shall not require 1-hour fire-resistance-rated construction where the building is equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3, and all of the following conditions are met: 2.1. For other than existing approved atriums with a smoke control system, where the atrium was constructed and is maintained in accordance with the code in effect at the time the atrium was created, the atrium shall have a smoke control system that is in compliance with Section 909. 2.2. Glass walls forming a smoke partition or a glass-block wall assembly shall be permitted where in compliance with Condition 2.2.1 or 2.2.2.
2.2.1. Glass walls forming a smoke partition shall be permitted where all of the following conditions are met:
2.2.1.1. Automatic sprinklers are provided along both sides of the separation wall and doors, or on the room side only if there is not a walkway or occupied space on the atrium side.
2.2.1.2. The sprinklers shall be not more than 12 inches (305 mm) away from the face of the glass and at intervals along the glass of not greater than 72 inches (1829 mm).
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CONSTRUCTION REQUIREMENTS FOR EXISTING BUILDINGS
2.2.1.3. Windows in the glass wall shall be nonoperating type. 2.2.1.4.
CEBC § 802.1 High relevance — show source text
- 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.
802.2 Vertical openings. Existing vertical openings shall comply with the provisions of Sections 802.2.1, 802.2.2 and 802.2.3.
802.2.1 Existing vertical openings. Existing interior vertical openings connecting two or more floors shall be enclosed with approved assemblies having a fire-resistance rating of not less than 1 hour with approved opening protectives.
Exceptions:
- Where vertical opening enclosure is not required by the California Building Code or the California Fire Code .
- Interior vertical openings other than stairways may be blocked at the floor and ceiling of the work area by installation of not less than 2 inches (51 mm) of solid wood or equivalent construction.
- The enclosure shall not be required where: 3.1. Connecting the main floor and mezzanines; or 3.2. All of the following conditions are met: 3.2.1. The communicating area has a low-hazard occupancy or has a moderate-hazard occupancy that is protected throughout by an automatic sprinkler system.
3.2.2. The lowest or next-to-the-lowest level is a street floor.
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ALTERATIONS—LEVEL 2
3.2.3. The entire area is open and unobstructed in a manner such that it is reasonable to assume that a fire in any part of the interconnected spaces will be readily obvious to all of the occupants. 3.2.4. Exit capacity is sufficient to provide egress simultaneously for all occupants of all levels by considering all areas to be a single floor area for the determination of required exit capacity. 3.2.5. Each floor level, considered separately, has not less than one-half of its individual required exit capacity provided by an exit or exits leading directly out of that level without having to traverse another communicating floor level or be exposed to the smoke or fire spreading from another communicating floor level.
Reserved.
In Group B occupancies, a minimum 30-minute enclosure shall be provided to protect all vertical openings not exceeding three stories. This enclosure, or the enclosure specified in Section 802.2.1, shall not be required in the following locations: 5.1. Buildings not exceeding 3,000 square feet (279 m [2] ) per floor. 5.2. Buildings protected throughout by an approved automatic fire sprinkler system.
In Group E occupancies, the enclosure shall not be required for vertical openings not exceeding two stories where the building is protected throughout by an approved automatic fire sprinkler system.
In Group F occupancies, the enclosure shall not be required in the following locations: 7.1. Vertical openings not exceeding two stories. 7.2. Special-purpose occupancies where necessary for manufacturing operations and direct access is provided to not fewer than one protected stairway. 7.3. Buildings protected throughout by an approved automatic sprinkler system.
Reserved.
CEBC § 1231.4 High relevance — show source text
1231.4 Enclosure of vertical openings. Elevator shafts, vent shafts and other vertical openings shall be enclosed, and the enclosure shall be as set forth in Chapter 7.
1231.5 Fire-extinguishing systems. Automatic fire-extinguishing systems, standpipes and basement pipe inlets shall be installed when and as required by Chapter 9.
1231.6 Existing Group I occupancies. Existing buildings housing existing protective social-care homes or facilities established prior to the effective date of these regulations may have their use continued if they conform, or are made to conform, to the following provisions.
1231.6.1 Use of floors. The use of floor levels in buildings of Type III, IV or V nonfire-rated construction may be as follows:
Nonambulatory—first floor only;
Ambulatory—not higher than the third-floor level, provided walls and partitions are constructed of materials equal in fire- resistive quality to that of wood lath and plaster in good repair and all walls are firestopped at each floor level.
1231.6.2 Enclosure of exits and vertical openings. Except for two-story structures housing ambulatory guests, all interior stairs shall be enclosed in accordance with Chapter 10. In lieu of stairway enclosures, floor separations or smoke barriers may be provided in such a manner that fire and smoke will not spread rapidly to floors above or otherwise impair exit facilities. In these instances, floor separations or smoke barriers shall have a fire resistance equal to not less than [1] / 2 -inch (12.7 mm) gypsum wall board on each side of wood studs with openings protected by not less than a 1 [3] / 4 -inch (44 mm) solid bonded wood-core door of the self-closing type. All other vertical openings shall be enclosed in accordance with the provisions of Chapter 7.
1231.6.3 Exit access. Each floor or portion thereof of buildings used for the housing of existing protective social-care homes or facili- ties shall have access to not less than two exits in such a manner as to furnish egress from the building or structure in the event of an emergency substantially equivalent to the provisions of Chapter 10. 1231.6.4 Corridor openings. Openings from rooms to interior corridors shall be protected by not less than 1 [3] / 4 -inch (44 mm) solid- bonded wood-core doors. Transoms and other similar openings shall be sealed with materials equivalent to existing corridor wall construction.
1231.6.5 Interior wall and ceiling finishes shall conform to the requirements for a Group R, Division 1 occupancy as specified in Chap- ter 8.
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INTERIOR ENVIRONMENT
1231.6.6 Automatic sprinkler systems shall be installed in existing protective social-care occupancies in accordance with the provi- sions of Chapter 9.
1231.6.7 Fire alarm systems. Automatic fire alarm systems shall be installed in existing protective social-care homes or facilities in accordance with the provisions of Chapter 9.
CEBC § 1.1. High relevance — show source text
met:
1.1. The doors shall be provided with vision panels of approved fire-protection-rated glazing so located as to furnish clear vision of the approach to the elevator. Such glazing shall not exceed 100 square inches (0.065 m [2] ) in area. 1.2. The doors shall be held open but be automatic-closing by activation of a fire alarm initiating device installed in accordance with the requirements of NFPA 72 as for Phase I Emergency Recall Operation, and shall be located at each floor served by the elevator; in the associated elevator machine room, control space, or control room; and in the elevator hoistway, where sprinklers are located in those hoistways. 1.3. The doors, when closed, shall have signs visible from the approach area stating: “WHEN THESE DOORS ARE CLOSED OR IN CASE OF FIRE, ELEVATORS ARE OUT OF SERVICE. USE EXIT.” 2. Buildings without occupied floors located more than 55 feet (16 764 mm) above or 25 feet (7620 mm) below the lowest level of fire department vehicle access where provided with automatic sprinkler systems installed in accordance with Section 903.3.1.1 or 903.3.1.2.
- Freight elevators in buildings provided with both automatic sprinkler systems installed in accordance with Section 903.3.1.1 or 903.3.1.2 and not less than one ASME 17.3-compliant elevator serving the same floors.
Elimination of previously installed Phase I emergency recall or Phase II emergency in-car systems shall not be permitted.
1103.3.3 Medical emergency elevator. For existing hoistways with elevator alterations, or replacements, where the elevator car dimensions do not comply with Section 3002.4.1a of the California Building Code. The elevator car dimensions and/or the clear entrance opening dimensions may be altered where it can be demonstrated to the local jurisdictional authority’s satisfaction that the proposed configuration will accommodate the designated gurney or stretcher with equivalent ease to the existing car and/or clear entrance conditions. Written documentation from the local authority shall be provided to the California Occupational Safety and Health Elevator Unit.
1103.4 Vertical openings. Interior vertical openings, including but not limited to stairways, elevator hoistways, service and utility shafts, that connect two or more stories of a building shall be enclosed or protected as specified in Sections 1103.4.1 through 1103.4.10.
1103.4.1 Group I-2 and I-3 occupancies. In Group I-2 and I-3 occupancies, interior vertical openings connecting two or more stories shall be protected with 1-hour fire-resistance-rated construction.
Exceptions:
- In Group I-2, unenclosed vertical openings not exceeding two connected stories and not concealed within the building construction shall be permitted as follows: 1.1. The unenclosed vertical openings shall be separated from other unenclosed vertical openings serving other floors by a smoke barrier. 1.2. The unenclosed vertical openings shall be separated from corridors by smoke partitions. 1.3. The unenclosed vertical openings shall be separated from other fire or smoke compartments on the same floors by a smoke barrier. 1.4. On other than the lowest level, the unenclosed vertical openings shall not serve as a required means of
CEBC § 3.2.3. High relevance — show source text
ALTERATIONS—LEVEL 2
3.2.3. The entire area is open and unobstructed in a manner such that it is reasonable to assume that a fire in any part of the interconnected spaces will be readily obvious to all of the occupants. 3.2.4. Exit capacity is sufficient to provide egress simultaneously for all occupants of all levels by considering all areas to be a single floor area for the determination of required exit capacity. 3.2.5. Each floor level, considered separately, has not less than one-half of its individual required exit capacity provided by an exit or exits leading directly out of that level without having to traverse another communicating floor level or be exposed to the smoke or fire spreading from another communicating floor level.
Reserved.
In Group B occupancies, a minimum 30-minute enclosure shall be provided to protect all vertical openings not exceeding three stories. This enclosure, or the enclosure specified in Section 802.2.1, shall not be required in the following locations: 5.1. Buildings not exceeding 3,000 square feet (279 m [2] ) per floor. 5.2. Buildings protected throughout by an approved automatic fire sprinkler system.
In Group E occupancies, the enclosure shall not be required for vertical openings not exceeding two stories where the building is protected throughout by an approved automatic fire sprinkler system.
In Group F occupancies, the enclosure shall not be required in the following locations: 7.1. Vertical openings not exceeding two stories. 7.2. Special-purpose occupancies where necessary for manufacturing operations and direct access is provided to not fewer than one protected stairway. 7.3. Buildings protected throughout by an approved automatic sprinkler system.
Reserved.
In Group M occupancies, a minimum 30-minute enclosure shall be provided to protect all vertical openings not exceeding three stories. This enclosure, or the enclosure specified in Section 802.2.1, shall not be required in the following locations: 9.1. Openings connecting only two floor levels. 9.2. Occupancies protected throughout by an approved automatic sprinkler system.
Reserved.
Reserved.
One- and two-family dwellings.
Group S occupancies where connecting not more than two floor levels or where connecting not more than three floor levels and the structure is equipped throughout with an approved automatic sprinkler system.
Group S occupancies where vertical opening protection is not required for open parking garages and ramps.
802.2.2 Supplemental shaft and floor opening enclosure requirements. Where the work area on any floor exceeds 50 percent of that floor area, the enclosure requirements of Section 802.2 shall apply to vertical openings other than stairways throughout the floor.
Exception: Vertical openings located in tenant spaces that are entirely outside the work area.
802.2.3 Supplemental stairway enclosure requirements. Where the work area on any floor exceeds 50 percent of that floor area, stairways that are part of the means of egress serving the work area shall, at a minimum, be enclosed with smoketight construction on the highest work area floor and all floors below.
Exception: Where stairway enclosure is not required by the California Building Code or the California Fire Code .
CEBC § 708.5 High relevance — show source text
708.5 Exterior walls. Where exterior walls serve as a part of a required fire-resistance-rated separation, such walls shall comply with the requirements of Section 705 for exterior walls, and the fire-resistance-rated separation requirements shall not apply.
Exception: Exterior walls required to be fire-resistance rated in accordance with Section 1021.2 for exterior egress balconies, Section 1023.7 for interior exit stairways and ramps and Section 1027.6 for exterior exit stairways and ramps.
708.6 Openings. Openings in a fire partition shall be protected in accordance with Section 716.
708.7 Penetrations. Penetrations of fire partitions shall comply with Section 714.
708.8 Joints. Joints made in or between fire partitions shall comply with Section 715.
708.9 Ducts and air transfer openings. Penetrations in a fire partition by ducts and air transfer openings shall comply with Section 717.
SECTION 709—SMOKE BARRIERS
709.1 General. Vertical and horizontal smoke barriers shall comply with this section.
709.2 Materials. Smoke barriers shall be of materials permitted by the building type of construction.
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FIRE AND SMOKE PROTECTION FEATURES
709.3 Fire-resistance rating. A 1-hour fire-resistance rating is required for smoke barriers.
Exception: Smoke barriers constructed of minimum 0.10-inch-thick (2.5 mm) steel in Group I-3 buildings.
709.4 Continuity. Smoke barriers shall form an effective membrane continuous from the top of the foundation or floor/ceiling assembly below to the underside of the floor or roof sheathing, deck or slab above, including continuity through concealed spaces, such as those found above suspended ceilings, and interstitial structural and mechanical spaces. The supporting construction shall be protected to afford the required fire-resistance rating of the wall or floor supported in buildings of other than Type IIB, IIIB or VB construction. Smoke-barrier walls used to separate smoke compartments shall comply with Section 709.4.1. Smoke-barrier walls used to enclose areas of refuge in accordance with Section 1009.6.4 or to enclose elevator lobbies in accordance with Section 405.4.3, 3007.6.2, or 3008.6.2 shall comply with Section 709.4.2.
Exception: Smoke-barrier walls are not required in interstitial spaces where such spaces are designed and constructed with ceilings or exterior walls that provide resistance to the passage of fire and smoke equivalent to that provided by the smoke-barrier walls.
709.4.1 Smoke-barrier assemblies separating smoke compartments. Smoke-barrier assemblies used to separate smoke compartments shall form an effective membrane enclosure that is continuous from an outside wall or smoke barrier wall to an outside wall or another smoke barrier wall and to the horizontal assemblies.
CEBC § 801.2 High relevance — show source text
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.
802.2 Vertical openings. Existing vertical openings shall comply with the provisions of Sections 802.2.1, 802.2.2 and 802.2.3.
802.2.1 Existing vertical openings. Existing interior vertical openings connecting two or more floors shall be enclosed with approved assemblies having a fire-resistance rating of not less than 1 hour with approved opening protectives.
Exceptions:
- Where vertical opening enclosure is not required by the California Building Code or the California Fire Code .
- Interior vertical openings other than stairways may be blocked at the floor and ceiling of the work area by installation of not less than 2 inches (51 mm) of solid wood or equivalent construction.
- The enclosure shall not be required where: 3.1. Connecting the main floor and mezzanines; or 3.2. All of the following conditions are met: 3.2.1. The communicating area has a low-hazard occupancy or has a moderate-hazard occupancy that is protected throughout by an automatic sprinkler system.
3.2.2. The lowest or next-to-the-lowest level is a street floor.
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ALTERATIONS—LEVEL 2
CEBC § 701.1 High relevance — show source text
701.1 Scope. Level 1 alterations as described in Section 602 shall comply with the requirements of this chapter. Alterations to historic buildings and structures shall comply with Part 8, Title 24, C.C.R.
701.2 Conformance. An existing building or portion thereof shall not be altered such that the building becomes less safe than its existing condition.
Exception: Where the current level of safety or sanitation is proposed to be reduced, the portion altered shall conform to the requirements of the California Building Code .
[BS] 701.3 Flood hazard areas. In flood hazard areas, alterations that constitute substantial improvement shall require that the building comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable.
SECTION 702—BUILDING ELEMENTS AND MATERIALS
702.1 Interior finishes. Newly installed interior wall and ceiling finishes shall comply with Chapter 8 of the California Building Code .
702.2 Interior floor finish. New interior floor finish, including new carpeting used as an interior floor finish material, shall comply with Section 804 of the California Building Code .
702.3 Interior trim. Newly installed interior trim materials shall comply with Section 806 of the California Building Code .
702.4 Window fall prevention. In Group R-2 or R-3 buildings containing dwelling units and one- and two-family dwellings and townhouses regulated by the California Residential Code, window opening control devices or other window fall prevention devices complying with ASTM F2090 shall be installed where an existing window is replaced and where all of the following apply to the replacement window:
- The window is operable.
- One of the following applies: 2.1. The window replacement includes replacement of the sash and frame. 2.2. The window replacement includes the sash only where the existing frame remains.
- One of the following applies: 3.1. In Group R-2 or R-3 buildings containing dwelling units, the bottom of the clear opening of the window opening is at a height less than 36 inches (915 mm) above the finished floor. 3.2. In one- and two-family dwellings and townhouses regulated by the California Residential Code, the bottom of the clear opening of the window opening is at a height less than 24 inches (610 mm) above the finished floor.
- The window will permit openings that will allow passage of a 4-inch-diameter (102 mm) sphere when the window is in its largest opened position.
- The vertical distance from the bottom of the clear opening of the window opening to the finished grade or other surface below, on the exterior of the building, is greater than 72 inches (1829 mm).
Exception: Operable windows where the bottom of the clear opening of the window opening is located more than 75 feet (22 860 mm) above the finished grade or other surface below, on the exterior of the room, space or building, and that are provided with window fall prevention devices that comply with ASTM F2006.
702.5 Replacement window for emergency escape and rescue openings. Where windows are required to provide emergency escape and rescue openings in Group R-2 and R-3 occupancies and one- and two-family dwellings and townhouses regulated by the California Residential Code, replacement windows shall be exempt from the requirements of Section 1031.3 of the California Building Code and Section R310.2 of the California Residential Code, provided that the replacement window meets the following conditions: 1.
CEBC § 304A.3.4.4 Medium relevance — show source text
304A.3.4.4 SPC 2 using ASCE 41-13. Structures shall be considered to comply with SPC 2 requirements of Table 2.5.3, Chapter 6 of the California Administrative Code, when all of the following are satisfied: 1. Life Safety Structural Performance Level (S-3) in accordance with Section 2.3.1.3 of ASCE 41-13 at BSE-1E; and 2. Items identified in Chapter 6, Article 10 of the California Administrative Code satisfying the requirements of Position Retention nonstructural Performance Level (N-B) in accordance with Section 2.3.2.2 of ASCE 41-13 at BSE-1E.
304A.3.4.5 SPC-4D using ASCE 41-13. Structures shall be deemed to comply with the SPC-4D requirements of Table 2.5.3, Chapter 6 of the California Administrative Code, when all of the following requirements in ASCE 41-13 are satisfied: 1. Damage control Structural Performance Level (S-2) in accordance with Section 2.3.1.2.1 of ASCE 41-13 at BSE-1E; and 2. Collapse Prevention Structural Performance Level (S-5) in accordance with Section 2.3.1.5 of ASCE 41-13 at BSE-2E; and 3. Items identified in Chapter 6, Article 10 of the California Administrative Code satisfy the requirements of Position Reten- tion Nonstructural Performance Level (N-B) in accordance with ASCE 41-13 Section 2.3.2.2 at BSE-1E.
304A.3.4.5.1 Replace ASCE 41-13 § 7.2.13.2 with the following: A. Where the adjacent building was constructed using the 1989 or later edition of the California Building Code and built under OSHPD jurisdiction, the minimum building separation distance specified in Section 7.2.13.1 need not be evalu- ated for Structural Performance Level Damage Control or lower.
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PROVISIONS FOR ALL COMPLIANCE METHODS
B. Where adjacent structure or building evaluated is not less than half as tall and adjacent structure has floors/levels that match those of the building being evaluated, the following exceptions apply: 1) For Structural Performance Level of Life Safety or lower, the seismic separation between the adjacent structure and the building being evaluated need not be evaluated. 2) For Structural Performance Level of Damage Control, buildings need not meet the minimum separation distance specified in Section 7.2.13.1 where either a) or b) applies: a) Adjacent structure is more than 2 inches (50.8 mm) times the number of stories below that level away from the building being evaluated at all floor levels that align. b) The adjacent building does not have any of the following structural deficiencies as defined in the Califor- nia Administrative Code (CAC), Chapter 6, Article 3: 1) Load path (3.1) 2) Weak story (3.3.1) 3) Soft story (3.3.2) 4) _Vertical discontinuity (3.
Frequently asked questions
When does the CEBC require a 1‑hour enclosure for vertical openings?
The CEBC requires a 1‑hour rated enclosure for existing interior vertical openings connecting two or more floors under § 802.2.1, except where specific CEBC/CBC/CFC exceptions apply (or where alternative blocking of 2 inches solid wood is used for non‑stair openings) .
If my work area is only 30% of the floor, do I still need to enclose stairways and shafts across the whole floor?
No — the supplemental floor‑wide enclosure and stair requirements (and the expansion of finish rules across the floor) are triggered when the work area exceeds 50 percent of the floor area; otherwise the baseline § 802.2/§ 802.4 obligations apply to the openings and corridors serving the work area itself .
Are there tolerances for existing, noncompliant interior finishes in exits/corridors?
Yes. CEBC § 802.4 allows existing materials that do not meet CBC Chapter 8 to be treated with an approved fire‑retardant coating and tested on the same (or similar) material to demonstrate required performance — follow manufacturer and testing guidance and document results for approval .
For Group I‑2 sleeping floors with >30 care recipients, what does CEBC require?
CEBC § 802.3 requires the story to be divided into not less than two smoke compartments by smoke barrier walls in accordance with CBC § 407.5; consult CBC § 407.5 for compartment area limits, refuge sizing and travel‑distance rules file.
Can I use the building sprinkler system to avoid vertical opening enclosures?
Some occupancy‑specific exceptions allow reduced enclosure requirements for sprinklered buildings, but Group I‑2 and other occupancies have limited exceptions; do not assume sprinklers remove the need for 1‑hour protection without checking the specific CEBC/CBC/CFC exception language referenced in § 802.2.1 and related code sections file.
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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