CBC · California Building Code

What are the differences and requirements for fire partitions, smoke barriers and smoke partitions?

In plain terms: fire partitions (§ 708) are walls used to separate spaces for fire safety and require protected openings and fireblocking or draftstops if they don’t extend fully; smoke barriers (§ 709, § 709.4) are continuous 1‑hour walls intended to stop the spread of smoke and must extend from foundation to underside of the floor/roof above; smoke partitions (§ 710, § 710.2) provide a lesser level of smoke control, usually need not be 1‑hour rated but must meet material, continuity and door/window sealing rules. Always check the specific occupancy chapters for size, compartment and door automation requirements.

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

Fire partitions are walls/partitions used to separate specific spaces and are governed by Section 708 (§ 708); they must meet the construction, opening protection, penetration and joint requirements called out in that section (and related sections) and, where they do not extend fully, require fireblocking or draftstopping (§ 708). Smoke barriers are continuous membranes intended to restrict smoke movement and (unless an exception applies) must have a 1‑hour fire‑resistance rating and be continuous from foundation/floor to underside of the assembly above (§ 709 and § 709.3, § 709.4). Smoke partitions are smoke‑resisting walls that are generally not required to be fire‑resistance‑rated but must meet material, continuity and opening control requirements in § 710 (see § 710.2–§ 710.4).

Requirements in detail

Quick comparison (decision‑relevant dimensions)

Feature / dimension	Fire partition	Smoke barrier	Smoke partition	Code Reference
Primary purpose	Fire separation between spaces or units	Restrict movement of smoke between smoke compartments	Limit transfer of smoke (lower level of protection than smoke barrier)	§ 708; § 709; § 710
Required fire‑resistance rating	Not universally stated in the retrieved excerpts (varies by use/occupancy) — see applicable code calls to § 708 and occupancy chapters	1 hour (unless exception for 0.10‑in steel in Group I‑3) — § 709.3	Not required unless called for elsewhere — § 710.3	§ 709.3; § 710.3
Continuity / vertical extent	If not continuous to underside of floor/roof, must provide fireblocking or draftstops in combustible construction (lists exceptions) — § 708.4.3	Must be continuous from top of foundation or floor below to underside of floor/roof sheathing/deck/slab above and through concealed/interstitial spaces — § 709.4	Extend from top of foundation/floor below to underside of floor/roof sheathing or to underside of ceiling that limits smoke transfer — § 710.4	§ 708.4.3; § 709.4; § 710.4
Openings (doors/windows)	Openings must be protected per Section 716 — § 708.6	Openings protected per § 716; special door rules for health‑care occupancies (automatic closing for hold‑open doors in certain corridors) — § 709.6, § 709.5.1	Windows must be sealed to resist free passage of smoke or be automatic‑closing on smoke detection; doors must meet smoke‑door or self/auto‑closing requirements; louvers prohibited — § 710.5, § 710.5.1–.3	§ 708.6; § 709.5–.6; § 710.5
Penetrations & joints	Penetrations: Section 714; joints: Section 715	Penetrations: Section 714; joints: Section 715	Penetrations/joints must meet the referenced sections where applicable	§ 714; § 715 (see §§ 708.7–.8; 709.6–.7; 710.5) file
Ducts & air transfer openings	Must comply with § 717 for penetrations through fire partitions	Must comply with § 717 for penetrations through smoke barriers	Duct/air‑transfer penetrations regulated; see § 717	§ 717; §§ 708.9; 709.8; 710.5 references
Special material requirement (Group I‑2 / R‑2.1)	See occupancy chapters; exceptions exist	See occupancy chapters for smoke‑barrier sizing/where required	In Group I‑2, framing must be covered with noncombustible materials with an approved thermal barrier index ≥ 15 — § 710.2	§ 710.2
Occupancy size / compartment limits (when smoke barriers are required)	Depends on occupancy; consult occupancy chapters	When required, smoke compartments generally not to exceed 22,500 sq ft and travel to a smoke barrier door ≤ 200 ft (applies in several occupancy rules)	Same as smoke barrier when used to subdivide stories — see occupancy sections	22,500 sq ft; 200 ft travel — occupancy rules referencing § 709

Notes on table sources: the table rows are drawn from § 708, § 709, § 709.4 and § 710.2 and associated subsections as shown in the CBC excerpts.

Fire partitions — detail (§ 708)

Section 708 governs fire partitions. Openings and penetrations in fire partitions must be protected in accordance with the opening‑protective and penetration sections (Section 716 and Section 714 respectively) and joints must comply with Section 715 (§ 708.6–708.8).
In combustible construction where a fire partition does not extend to the underside of the floor or roof sheathing, the code requires fireblocking or draftstopping above the partition (with several exceptions, for example full‑building sprinklers and specific R‑occupancy exceptions) (§ 708.4.3). Do not assume an unbroken vertical extension is optional without checking those fireblocking/draftstop rules.

Smoke barriers — detail (§ 709, § 709.4)

Purpose and rating: smoke barriers are intended to form an effective membrane to restrict smoke movement; they require a 1‑hour fire‑resistance rating (§ 709.1, § 709.3). Exception: smoke barriers of minimum 0.10‑inch thick steel are permitted in Group I‑3 under the exception to § 709.3.
Continuity: smoke barriers must be continuous from the top of the foundation or floor below to the underside of the floor/roof sheathing, deck or slab above, and must maintain continuity through concealed/interstitial spaces (§ 709.4). There is an explicit exception for interstitial spaces that are constructed to provide equivalent resistance to passage of fire and smoke. § 709.4 also specifies added continuity requirements where smoke barriers separate smoke compartments or enclose areas of refuge or elevator lobbies (see § 709.4.1–709.4.2).
Openings and specialized door rules: openings in smoke barriers must meet Section 716; certain occupancies (e.g., Group I‑2, R‑2.1, and ambulatory care) have additional door requirements (automatic‑closing on hold‑open devices across corridors, vision‑panel limits, etc.) (§ 709.5.1). Penetrations and joints follow § 714 and § 715; ducts/air transfer openings follow § 717 (§ 709.6–709.8).

Smoke partitions — detail (§ 710, § 710.2)

Materials: § 710.2 requires smoke partitions be constructed of materials permitted by the building type of construction. For Group I‑2, smoke‑partition framing must be covered with noncombustible materials having an approved thermal barrier with an index ≥ 15 (referenced test standards included).
Fire‑resistance rating: unless some other part of the code requires a rating, smoke partitions are not required to be fire‑resistance rated (§ 710.3).
Continuity: smoke partitions must extend from the top of foundation/floor below to the underside of floor/roof sheathing or to the underside of a ceiling that is constructed to limit smoke transfer. There is an explicit exception allowing lay‑in ceilings to be treated as limiting smoke transfer in Group I‑2 when certain weights and HVAC ducting conditions are met (§ 710.4 and exception).
Openings: windows in smoke partitions must be sealed against free smoke passage or automatic‑closing on smoke detection (§ 710.5.1). Doors must not have louvers (except as permitted elsewhere) and, where required, must meet smoke and draft control door criteria (UL 1784 leakage limits) and be installed per NFPA 105; where required by other code sections, doors must be self‑ or automatic‑closing by smoke detection (§ 710.5.2–.3).

Exceptions & special cases

Interstitial spaces: smoke‑barrier walls are not required in interstitial spaces where the space is constructed with ceilings or exterior walls that provide resistance to passage of fire/smoke equivalent to a smoke‑barrier wall (§ 709.4, exception).
Group‑specific deviations: certain occupancies (Group I‑2, R‑2.1, I‑3, ambulatory care, etc.) have specific smoke‑barrier/partition thresholds, occupant limits, restraint rules and material prescriptions referenced in occupancy chapters and appendices; for example, where smoke barriers are required the smoke compartment area is commonly limited to 22,500 sq ft and the travel distance to a smoke‑barrier door is limited to 200 ft in multiple occupancy provisions (§ 709 reference in occupancy rules). Always check the occupancy chapter (e.g., Group I‑2 rules) in addition to § 709–§ 710.
Lay‑in ceilings in Group I‑2: a lay‑in ceiling system with tiles ≥ 1 lb/ft2 and fully ducted HVAC can be considered to limit smoke transfer so a smoke partition may terminate at the underside of that ceiling (§ 710.4, exception).
Thin steel exception for I‑3: smoke barriers of minimum 0.10‑inch‑thick steel are allowed in Group I‑3 under the § 709.3 exception even though the general smoke‑barrier rating is 1 hour.

Common mistakes

Treating smoke partitions as equivalent to smoke barriers. Smoke partitions do not carry the same continuity and rating obligations as smoke barriers and are not inherently 1‑hour rated; check § 710.3 vs § 709.3.
Forgetting to protect openings/penetrations. Openings in fire partitions, smoke barriers and smoke partitions must be protected per Section 716 and penetrations must comply with § 714; neglecting these is a frequent error. file
Assuming vertical continuity is optional. When a fire partition does not extend fully, combustible construction requires fireblocking or draftstops per § 708.4.3 (with defined exceptions) — do not simply terminate the partition without the required blocking or system compliance.
Installing louvers or non‑rated doors in smoke partitions where prohibited. Doors in smoke partitions must not include louvers ( § 710.5.2.1) and where smoke and draft control doors are required they must meet UL 1784 leakage limits and NFPA 105 installation standards.

Worked example — hospital floor subdivision

Scenario: An acute‑care floor (Group I‑2) is 18,000 sq ft and must be subdivided into smoke compartments.

Are smoke barriers required? Yes — occupancy rules for many health‑care occupancies require smoke barriers to subdivide stories used for sleeping or care; when required they must follow § 709. (Check the specific Group I‑2 chapter for threshold triggers.)
Compartment sizing: the 18,000 sq ft floor is under the common single‑compartment maximum of 22,500 sq ft, but the story must be divided into not fewer than two smoke compartments where the occupancy chapter requires subdivision (if the occupancy rule triggers subdivision, divide floor area into two compartments as required). If two compartments are required, each compartment could be ~9,000 sq ft — both below 22,500 sq ft and within travel distance limits (≤ 200 ft) if corridors and paths comply with the travel‑distance rules referenced in the occupancy section. § 709 and occupancy references apply.
Construction: smoke barriers used here must be continuous from foundation/floor below to underside of floor/roof sheathing (or meet the continuity rules in § 709.4), and must have a 1‑hour rating per § 709.3 (unless the narrow steel exception for I‑3 applies, which it does not for this I‑2 hospital). Openings in the smoke barrier (doors, windows) must be protected per § 716; doors across corridors in I‑2 that are held open must be automatic‑closing per § 709.5.1.
Ducts/penetrations: any penetrations of the smoke barrier must comply with § 714 and § 717 for ducts/air transfer openings to maintain the barrier integrity.

Result: Build two continuous 1‑hour smoke‑barrier walls meeting continuity, opening and penetration protections; verify compartment travel distances and provide required door automation and firestop details per § 709, § 716 and § 714.

Related provisions (useful cross‑references)

Opening protectives — § 716 (opening protection requirements referenced by all three sections)
Penetrations (through‑penetrations and membrane penetrations) — § 714 (penetration firestopping and sleeves)
Joints and voids — § 715 (joints made in or between partitions/barriers)
Ducts and air transfer openings — § 717 (penetrations of partitions/barriers by HVAC)
Smoke‑control and pressure differentials (mechanical smoke control systems) — Chapter 9 of the Fire Code (pressure difference, testing) — see California Fire Code references used with smoke barriers in design/testing contexts.
Maintenance and owner responsibilities for smoke barriers/partitions — § 701 (maintenance and inspection duties)

Code references

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

CBC § 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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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.
CBC § 1010.1.1. High relevance — show source text
Positive latching devices are not required. Factory-applied or field-applied protective plates are not required to be labeled. Doors installed across corridors shall comply with Section 1010.1.1. 2. In Group I- 2, R-2.1 and ambulatory care facilities, special purpose horizontal sliding, accordion or folding doors installed in accordance with Section 1010.3.3 and protected in accordance with Section 716. Doors installed across corridors shall comply with Section 1010.1.1.

709.5.1 Group I-2, R-2.1 and ambulatory care facilities. In Group I-2, R-2.1 and ambulatory care facilities, where doors protecting openings in smoke barriers are installed across a corridor and have hold-open devices, the doors shall be automatic-closing in accordance with Section 716.2.6.6. Such doors shall have a vision panel with fire-protection-rated glazing materials in fire-protection-rated frames, the area of which shall not exceed that tested. In Group I-2, where swinging doors are installed across a corridor, such doors shall be opposite swinging pairs.

709.6 Penetrations. Penetrations of smoke barriers shall comply with Section 714.

709.7 Joints. Joints made in or between smoke barriers shall comply with Section 715.

709.8 Ducts and air transfer openings. Penetrations in a smoke barrier by ducts and air transfer openings shall comply with Section 717.

SECTION 710—SMOKE PARTITIONS

710.1 General. Smoke partitions installed as required elsewhere in the code shall comply with this section.

710.2 Materials. The walls shall be of materials permitted by the building type of construction. In Group I-2, smoke partitions shall have framing covered with noncombustible materials having an approved thermal barrier with an index of not less than 15 in accor- dance with FM 4880, UL 1040, NFPA 286 or UL 1715.

710.3 Fire-resistance rating. Unless required elsewhere in the code, smoke partitions are not required to have a fire-resistance rating.

710.4 Continuity. Smoke partitions shall extend from the top of the foundation or floor below to the underside of the floor or roof sheathing, deck or slab above or to the underside of the ceiling above where the ceiling membrane is constructed to limit the transfer of smoke.

Exception: In Group I-2, a lay-in ceiling system shall be considered capable of limiting the transfer of smoke where the ceiling tiles weigh not less than 1 pound per square foot (4.882 kg/m2) and where the HVAC system is fully ducted in accordance with the Cali- fornia Mechanical Code.

710.4.1 Smoke partition walls enclosing elevator lobbies. Smoke partition walls used to enclose elevator lobbies in accordance with Section 3006.3 shall form an enclosure that terminates at a fire barrier having a fire-resistance rating of not less than 1 hour, another smoke partition or an outside wall.

710.5 Openings. Openings in smoke partitions shall comply with Sections 710.5.1 through 710.5.3.

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CBC § 1.11. High relevance — show source text
- The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Fire Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.
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7 FIRE AND SMOKE PROTECTION FEATURES

User notes:

About this chapter: Chapter 7 provides requirements to maintain the fire-resistance ratings of building elements and to limit fire spread. Section 701 addresses the maintenance of and owner’s responsibility for construction elements such as fire barriers and smoke barriers. The rest of the chapter deals with various aspects that also must be maintained to achieve overall fire resistance of the main fire- and smoke-resistive features. These include penetrations, joint protection, door and window openings, and duct and air transfer opening protection.

SECTION 701—GENERAL

701.1 Scope. The provisions of this chapter shall govern the inspection and maintenance of the materials, systems and assemblies used for structural fire resistance, fire-resistance-rated construction separation of adjacent spaces and construction installed to resist the passage of smoke to safeguard against the spread of fire and smoke within a building and the spread of fire to or from buildings. New buildings shall comply with the California Building Code.

701.2 Fire-resistance-rated construction. The fire-resistance rating of the following fire-resistance-rated construction shall be maintained:
1. Structural members.
2. Exterior walls.
3. Fire walls, fire barriers, fire partitions.
4. Horizontal assemblies.
5. Shaft enclosures.
701.2.1 Hanging displays. The hanging and displaying of salable goods and other decorative materials from acoustical ceiling systems that are part of a fire-resistance-rated horizontal assembly shall be prohibited.

701.3 Smoke barriers. The fire-resistance rating and smoke-resistant characteristics of smoke barriers shall be maintained.

701.4 Smoke partitions. The smoke-resistant characteristics of smoke partitions shall be maintained.

701.5 Maintaining protection. Materials, systems and devices used to repair or protect breaches and openings in fire-resistance-rated construction and construction installed to resist the passage of smoke shall be maintained in accordance with Sections 703 through 707.

701.6 Owner’s responsibility. The owner shall maintain an inventory of all required fire-resistance-rated construction, construction installed to resist the passage of smoke and the construction included in Sections 703 through 707 and Sections 602.4.1 and 602.4.2 of the California Building Code . Such construction shall be visually inspected by the owner annually and properly repaired, restored or replaced where damaged, altered, breached or penetrated. Where concealed, such elements shall not be required to be visually inspected by the owner unless the concealed space is accessible by the removal or movement of a panel, access door, ceiling tile or similar movable entry to the space.
CBC § 2.1 High relevance — show source text
ICC code development note: Code change proposals to this appendix will be considered by the IFC Code Development Committee during the 2024 (Group A) Code Development Cycle.

SECTION K101—GENERAL

K101.1 Scope. The provisions of this chapter shall apply to existing buildings containing ambulatory care facilities in addition to the requirements of Chapter 11. Where the provisions of this chapter conflict with either the construction requirements in Chapter 11 or the construction requirements that applied at the time of construction, the most restrictive provision shall apply.

K101.2 Intent. The intent of this appendix is to provide a minimum degree of fire and life safety to persons occupying and existing buildings containing ambulatory care facilities where such buildings do not comply with the minimum requirements of the California Building Code .

SECTION K102—FIRE SAFETY REQUIREMENTS FOR EXISTING AMBULATORY CARE FACILITIES

K102.1 Separation. Ambulatory care facilities where the potential exists for four or more care recipients to be incapable of self-preservation at any time, whether rendered incapable by staff or staff has accepted responsibility for a care recipient already incapable, shall be separated from adjacent spaces, corridors or tenants with a fire partition installed in accordance with Section 708 of the Cali- fornia Building Code .

K102.2 Smoke compartments. Where the aggregate area of one or more ambulatory care facilities is greater than 10,000 square feet (929 m [2] ) on one story, the story shall be provided with a smoke barrier to subdivide the story into not fewer than two smoke compartments. The area of any one such smoke compartment shall be not greater than 22,500 square feet (2092 m [2] ). The travel distance from any point in a smoke compartment to a smoke barrier door shall be not greater than 200 feet (60 960 mm). The smoke barrier shall be installed in accordance with Section 709 of the California Building Code with the exception that smoke barriers shall be continuous from an outside wall to an outside wall, a floor to a floor, or from a smoke barrier to a smoke barrier or a combination thereof.

K102.2.1 Refuge area. Not less than 30 net square feet (2.8 m [2] ) for each nonambulatory care recipient shall be provided within the aggregate area of corridors, care recipient rooms, treatment rooms, lounge or dining areas and other low-hazard areas within each smoke compartment. Each occupant of an ambulatory care facility shall be provided with access to a refuge area without passing through or utilizing adjacent tenant spaces.

K102.2.2 Smoke barriers. Smoke barriers shall be constructed in accordance with Sections 422 and 709 of the California Building Code .

Exceptions:
1. Smoke barriers shall be permitted to terminate at an atrium enclosure in accordance with Section 404.6 of the Califor- nia Building Code .
2. Smoke barriers shall be continuous from an outside wall to an outside wall, a floor to a floor, a smoke barrier to a smoke barrier or a combination thereof.
K102.2.3 Opening protectives. Openings in smoke barriers shall be protected in accordance with Section 716 of the California Building Code . Opening protectives shall have a minimum fire protection rating of [1] / 3 hour.

Exception: Existing wired glass vision panels in doors shall be permitted to remain.

K102.2.4 Penetrations. Penetrations of smoke barriers shall comply with the California Building Code .

Exception: Approved existing materials and methods of construction.
CBC § 2.1 High relevance — show source text
Group R-2.1 occupancies housing bedridden clients shall be provided with smoke barriers constructed in accordance with Section 710 of the California Building Code regardless of the number of clients. When smoke barriers are required, the area within a smoke compartment shall not exceed 22,500 square feet (2090 m [2] ) nor shall its travel distance exceed 200 feet (60 960 mm). Such smoke barriers shall divide the floor as equally as possible.

435.5.2 Smoke partitions. Group R-2.1 occupancies where smoke partitions are required, framing shall be covered with noncombus- tible materials having an approved thermal barrier with an index of not less than 15 in accordance with FM 4880, UL 1040, NFPA 286 or UL 1715.

435.5.3 Independent egress. At least two means of egress shall be provided from each smoke compartment created by smoke barri- ers. Means of egress may pass through adjacent compartments provided it does not return through the smoke compartment from which means of egress originated.

435.6 Interior finish provisions.

435.6.1 Interior wall and ceiling finish. Group R-3.1 occupancies housing a bedridden client shall comply with Interior Wall and Ceil- ing Finish requirements specified for Group I-2 occupancies in Table 903.3 of the California Building Code.

435.6.2 Safety padding. Padding material used on walls, floors and ceilings in Group I and R-2.1 occupancies shall be of an approved type tested in accordance with the procedures established by State Fire Marshal Standard 12-8-100, Room Fire Test for Wall and Ceil- ing Materials, California Code of Regulations, Title 24, Part 12.

435.7 Fire Protection system provisions.

435.7.1 Automatic sprinkler systems in Group R-2.1, R-3.1 and R-4 occupancies. An automatic sprinkler system shall be installed where required in Section 903.

435.7.2 Fire alarm systems in Group R-2.1 and R-4 occupancies. An approved fire alarm system shall be installed where required in Section 907.

435.7.3 Smoke alarms in Groups R-2.1, R-3.1 and R-4 occupancies. Smoke alarms shall be installed where required in Section 907.2.11.2.

435.7.4 Hearing impaired. See Section 907.5.2.3.5.

435.8 Means of egress provisions.

435.8.1 General. In addition to the general means of egress requirements of Chapter 10, this section shall apply to Group R-2.1, R-3.1 and R-4 occupancies.

435.8.2 Number of exits.

435.8.2.1 Group R-2.1, R-3.1 and R-4 occupancies shall have a minimum of two exits.

Exception. Ancillary use areas or occupancies shall have egress as required by Section 1021.

435.8.3 Egress arrangements.

435.8.3.1 Egress through adjoining dwelling units shall not be permitted.
CBC § 435.3.3 High relevance — show source text
Every licensee admitting or retaining a bedridden resident shall, within 48 hours of the resident’s admission or retention in the facil- ity, notify the local fire authority with jurisdiction of the estimated length of time the resident will retain his or her bedridden status in the facility.

435.3.3 Limitations seven or more clients. Group R-4 occupancies, where nonambulatory clients are housed above the first story and there is more than 3,000 square feet (279 m [2] ) of floor area above the first story or housing not more than 16 clients above the first story, shall be constructed of not less than 1-hour fire-resistance-rated construction throughout.

435.3.4 Ambulatory and nonambulatory elderly clients. Group R-4 occupancies housing nonambulatory elderly clients shall be of not less than 1-hour fire-resistance-rated construction throughout.

435.4 Type of construction provisions.

435.4.1 Group R-2.1, occupancies are not permitted in non-fire-resistance-rated construction, see Health and Safety Code, Section 13131.5.

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APPENDIX CHAPTER 4—SPECIAL DETAILED REQUIREMENTS BASED ON USE AND OCCUPANCY

435.5 Fire-resistance-rated construction provisions.

435.5.1 Smoke barriers required. Group R-2.1 and R-4 occupancies licensed as a Residential Care Facility (RCF) with individual floor areas over 6000 square feet (557 m [2] ) per floor, shall be provided with smoke barriers, constructed in accordance with Section 710 of the California Building Code.

Group R-2.1 occupancies housing bedridden clients shall be provided with smoke barriers constructed in accordance with Section 710 of the California Building Code regardless of the number of clients. When smoke barriers are required, the area within a smoke compartment shall not exceed 22,500 square feet (2090 m [2] ) nor shall its travel distance exceed 200 feet (60 960 mm). Such smoke barriers shall divide the floor as equally as possible.

435.5.2 Smoke partitions. Group R-2.1 occupancies where smoke partitions are required, framing shall be covered with noncombus- tible materials having an approved thermal barrier with an index of not less than 15 in accordance with FM 4880, UL 1040, NFPA 286 or UL 1715.

435.5.3 Independent egress. At least two means of egress shall be provided from each smoke compartment created by smoke barri- ers. Means of egress may pass through adjacent compartments provided it does not return through the smoke compartment from which means of egress originated.

435.6 Interior finish provisions.

435.6.1 Interior wall and ceiling finish. Group R-3.1 occupancies housing a bedridden client shall comply with Interior Wall and Ceil- ing Finish requirements specified for Group I-2 occupancies in Table 903.3 of the California Building Code.
CBC § 708.4.3 High relevance — show source text
Exception: In buildings of Types IIB, IIIB and VB construction, the supporting construction requirement shall not apply to fire partitions separating tenant spaces in covered and open mall buildings, fire partitions separating dwelling units, fire partitions separating sleeping units, fire partitions serving as corridor walls, fire partitions separating ambulatory care facilities from adjacent spaces or corridors, fire partitions separating dwelling and sleeping units from Group R-1 and R-2 occupancies and fire partitions separating vestibules from the level of exit discharge.

708.4.3 Fireblocks and draftstops in combustible construction. In combustible construction where fire partitions do not extend to the underside of the floor or roof sheathing, deck or slab above, the space above and along the line of the fire partition shall be provided with one of the following:
1. Fireblocking up to the underside of the floor or roof sheathing, deck or slab above using materials complying with Section 718.2.1.
2. Draftstops up to the underside of the floor or roof sheathing, deck or slab above using materials complying with Section 718.3.1 for floors or Section 718.4.1 for attics.
Exceptions:
1. Buildings equipped with an automatic sprinkler system installed throughout in accordance with Section 903.3.1.1, or in accordance with Section 903.3.1.2 provided that protection is provided in the space between the top of the fire partition and underside of the floor or roof sheathing, deck or slab above as required for systems complying with Section 903.3.1.1.
2. Where corridor walls provide a sleeping unit or dwelling unit separation, draftstops shall only be required above one of the corridor walls.
3. In Group R-2 occupancies with fewer than four dwelling units, fireblocking and draftstops shall not be required.
4. In Group R-2 occupancies up to and including four stories in height in buildings not exceeding 60 feet (18 288 mm) in height above grade plane, the attic space shall be subdivided by draftstops into areas not exceeding 3,000 square feet (279 m [2] ) or above every two dwelling units, whichever is smaller.
5. In Group R-3 occupancies with fewer than three dwelling units, fireblocking and draftstops shall not be required in floor assemblies.
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.

2025 CALIFORNIA BUILDING CODE 7-17
CBC § 710.2 High relevance — show source text
710.2 Materials. The walls shall be of materials permitted by the building type of construction. In Group I-2, smoke partitions shall have framing covered with noncombustible materials having an approved thermal barrier with an index of not less than 15 in accor- dance with FM 4880, UL 1040, NFPA 286 or UL 1715.

710.3 Fire-resistance rating. Unless required elsewhere in the code, smoke partitions are not required to have a fire-resistance rating.

710.4 Continuity. Smoke partitions shall extend from the top of the foundation or floor below to the underside of the floor or roof sheathing, deck or slab above or to the underside of the ceiling above where the ceiling membrane is constructed to limit the transfer of smoke.

Exception: In Group I-2, a lay-in ceiling system shall be considered capable of limiting the transfer of smoke where the ceiling tiles weigh not less than 1 pound per square foot (4.882 kg/m2) and where the HVAC system is fully ducted in accordance with the Cali- fornia Mechanical Code.

710.4.1 Smoke partition walls enclosing elevator lobbies. Smoke partition walls used to enclose elevator lobbies in accordance with Section 3006.3 shall form an enclosure that terminates at a fire barrier having a fire-resistance rating of not less than 1 hour, another smoke partition or an outside wall.

710.5 Openings. Openings in smoke partitions shall comply with Sections 710.5.1 through 710.5.3.

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FIRE AND SMOKE PROTECTION FEATURES

710.5.1 Windows. Windows in smoke partitions shall be sealed to resist the free passage of smoke or be automatic-closing upon detection of smoke.

710.5.2 Doors. Doors in smoke partitions shall comply with Sections 710.5.2.1 through 710.5.2.3.

710.5.2.1 Louvers. Doors in smoke partitions shall not include louvers.

Exception: Where permitted in accordance with Section 407.3.1.1.

710.5.2.2 Smoke and draft control doors. Where required elsewhere in the code, doors in smoke partitions shall meet the requirements for a smoke and draft control door assembly tested in accordance with UL 1784. The air leakage rate of the door assembly shall not exceed 3.0 cubic feet per minute per square foot [0.015424 m [3] /(s × m [2] )] of door opening at 0.10 inch of water (25 Pa) for both the ambient temperature test and the elevated temperature exposure test. Installation of smoke doors shall be in accordance with NFPA 105.

710.5.2.2.1 Smoke and draft control door labeling. Smoke and draft control doors complying only with UL 1784 shall be permitted to show the letter “S” on the manufacturer’s labeling.

710.5.2.3 Self- or automatic-closing doors. Where required elsewhere in the code, doors in smoke partitions shall be self- or automatic-closing by smoke detection in accordance with Section 716.2.6.6.
CBC § 92.9 Medium relevance — show source text
(See the California Fire Code.) Actuation of an initiating_ device shall sound an audible alarm throughout the entire story. When a building fire alarm system is required by other provisions of this code or the Fire Code, the alarm system shall be connected to the building alarm system. An approved alarm signal shall sound at an approved location in the Group I-4 facility to indicate a fire alarm or sprin- kler flow condition in other portions of the building; and 2.3. Group I-4 child-care center or adult day care, if more than 1,000 square feet (92.9 m [2] ) in area, is divided into at least two compartments of approximately the same size by a smoke barrier with door openings protected by smoke- and draft-control assemblies having a fire-protection rating of not less than 20 minutes. Smoke barriers shall have a fire-resistive rating of not less than one hour. In addition to the requirements of Section 508.3.3 of the California Building Code, occupancy separations between Group I-4 child-care center or adult day care and other occupan- cies shall be constructed as smoke barriers. Door openings in the smoke barrier shall be tightfittinq, with gaskets installed as required by Section 710 of the California Building Code, and shall be automatic closing by actuation of the automatic sprinklers, fire alarm or smoke-detection system. 2.4. Each compartment formed by the smoke barrier has not less than two exits or exit access doors, one of which is permitted to pass through the adjoining compartment; and 2.5. Where two or more exits or exit access are required, at least one shall not share a common path of travel. The egress system shall comply with the requirements of Section 709 for smoke barriers. 2.6. The building is equipped with an automatic sprinkler system throughout.

436.1.1 Egress. Rooms used for Group I-4 child-care or adult day care on the first floor shall have one exit door directly to the exterior.

Exception: One-hour rated corridors with a minimum width of 60 inches (1524 mm).

SECTION 452—SCHOOL FACILITIES FOR KINDERGARTEN THROUGH 12TH GRADE AND GROUP E CHILD-CARE

452.1 General provisions . School facilities for Kindergarten through 12th grade and Group E day care shall comply with the provisions of this section and other applicable provisions of this code including requirements for specific occupancies.

452.1.1 Location on property. All buildings housing Group E occupancies shall front directly on a public street or an exit discharge not less than 20 feet (6096 mm) in width. The exit discharge to the public street shall be a minimum 20-foot-wide (6096 mm) right-of-

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APPENDIX CHAPTER 4—SPECIAL DETAILED REQUIREMENTS BASED ON USE AND OCCUPANCY

way, unobstructed and maintained only as access to the public street. At least one required exit shall be located on the public street or on the exit discharge.
CBC § 408.5 Medium relevance — show source text
408.5 Protection of vertical openings. Any vertical opening shall be protected by a shaft enclosure in accordance with Section 713, or shall be in accordance with Section 408.5.1.

408.5.1 Floor openings. The open space in front of a cell tier and connected chases, not exceeding two tiers in height, shall not be considered a vertical shaft and need not meet the fire-resistive shaft enclosure requirements of Section 713.

408.5.2 Shaft openings in communicating floor levels. Where a floor opening is permitted between communicating floor levels of a housing unit in accordance with Section 408.5.1, plumbing chases serving vertically stacked individual cells contained with the housing unit shall be permitted without a shaft enclosure.

[BE] 408.6 Smoke barrier. Occupancies in Group I-3 shall have smoke barriers complying with Sections 408.6 and 709 to divide every story occupied by residents for sleeping, or any other story having an occupant load of 50 or more persons, into not fewer than two smoke compartments.

Exception: Spaces having a direct exit to one of the following, provided that the locking arrangement of the doors involved complies with the requirements for doors at the smoke barrier for the use condition involved:
1. A public way.
2. A building separated from the resident housing area by a 2-hour fire-resistance-rated assembly or 50 feet (15 240 mm) of
open space. 3. A secured yard or court having a holding space 50 feet (15 240 mm) from the housing area that provides 6 square feet (0.56 m [2] ) or more of refuge area per occupant, including residents, staff and visitors. 4. Holding facility.

[BE] 408.6.1 Smoke compartments. The number of residents in any smoke compartment shall be not more than 200. The distance of travel to a door in a smoke barrier from any room door required as exit access shall be not greater than 150 feet (45 720 mm). The distance of travel to a door in a smoke barrier from any point in a room shall be not greater than 200 feet (60 960 mm).

Exception: The travel distance may be increased by 50 feet from areas open only to the staff.

[BE] 408.6.2 Refuge area. Not less than 6 net square feet (0.56 m [2] ) per occupant shall be provided on each side of each smoke barrier for the total number of occupants in adjoining smoke compartments. This space shall be readily available wherever the occupants are moved across the smoke barrier in a fire emergency.

[BE] 408.6.3 Independent egress. A means of egress shall be provided from each smoke compartment created by smoke barriers without having to return through the smoke compartment from which means of egress originates.

408.7 Security glazing. In occupancies in Group I-3, windows and doors in 1-hour fire barriers constructed in accordance with Section 707, fire partitions constructed in accordance with Section 708 and smoke barriers constructed in accordance with Section 709 shall be permitted to have security glazing installed provided that the following conditions are met.
1. Individual panels of glazing shall not exceed 1,296 square inches (0.84 m [2] ).
2. The glazing shall be protected on both sides by an automatic sprinkler system. The sprinkler system shall be designed to, when actuated, wet completely the entire surface of any glazing affected by fire.
CBC § 2.1 Medium relevance — show source text
SECTION 420—GROUPS R-1, R-2, R-2.1, R-2.2, R-3, R-3.1 AND R-4

420.1 General. Occupancies in Groups R-1, R-2, R-2.1, R-2.2, R-3, R-3.1 and R-4 shall comply with the provisions of Sections 420.1 through 420.11 and other applicable provisions of this code.

420.2 Separation walls. Walls separating dwelling units in the same building, walls separating sleeping units in the same building, walls separating dwelling units from sleeping units in the same building and walls separating dwelling or sleeping units from other occupancies contiguous to them in the same building shall be constructed as fire partitions in accordance with Section 708.

420.3 Horizontal separation. Floor assemblies separating dwelling units in the same buildings, floor assemblies separating sleeping units in the same building, floor assemblies separating dwelling units from sleeping units in the same building and floor assemblies separating dwelling or sleeping units from other occupancies contiguous to them in the same building shall be constructed as horizontal assemblies in accordance with Section 711.

[F] 420.4 Automatic sprinkler system. Group R occupancies shall be equipped throughout with an automatic sprinkler system in accordance with Section 903.2.8. Group R-2.2 shall be equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1. Group R-2.1 occupancies shall be equipped throughout with an automatic sprinkler system in accordance with Section 903.2.6. Quick-response or residential automatic sprinklers shall be installed in accordance with Section 903.3.2.

[F] 420.5 Fire alarm systems and smoke alarms. Fire alarm systems and smoke alarms shall be provided in Group R-1, R-2 and R-2.1 occupancies in accordance with Sections 907.2.6, 907.2.8 and 907.2.9 and 907.2.10, respectively. Single- or multiple-station smoke alarms shall be provided in Groups R-2, R-2.1, R-3 and R-4 in accordance with Section 907.2.11. Group R-2.2 shall be equipped through- out with an automatic fire alarm systems per 907.2.9.2 and shall have a manual fire alarm pull station at the 24-hour staff watch office.

420.6 Smoke barriers in Group R-2.1 . Smoke barriers shall be provided in Group R-2.1 to subdivide every story used by persons receiving care, treatment or sleeping and to provide other stories with an occupant load of 50 or more persons, into not fewer than two smoke compartments. Such stories shall be divided into smoke compartments with an area of not more than 22,500 square feet (2092 m [2] ) and the distance of travel from any point in a smoke compartment to a smoke barrier door shall not exceed 200 feet (60 960 mm). The smoke barrier shall be in accordance with Section 709.

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SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE

Frequently asked questions

What is the single most important difference between a smoke barrier and a smoke partition?

A smoke barrier is an intended continuous membrane with a required 1‑hour fire‑resistance rating (unless an explicit exception applies) and stricter continuity rules (§ 709.3, § 709.4); a smoke partition provides smoke control but is generally not required to be fire‑resistance rated (§ 710.3).

Do smoke partitions ever need to be fire‑rated?

Yes — if another code requirement (occupancy chapter, egress/compartmentalization rule, or specific project condition) requires a fire‑resistance rating, a smoke partition must meet that requirement; otherwise § 710.3 states no rating is required. Always confirm with the applicable occupancy rules.

Can I terminate a smoke partition at a lay‑in ceiling?

In Group I‑2 occupancies a lay‑in ceiling system that meets the weight and HVAC ducting conditions in the § 710.4 exception may be considered to limit smoke transfer so the partition may terminate at the ceiling; otherwise, smoke partitions must extend to the underside of the floor/roof or sheathing above (§ 710.4).

Where do I find the requirements for protecting penetrations in these walls?

Penetrations for fire partitions, smoke barriers and smoke partitions are regulated by Section 714; ducts and air transfer openings are specifically covered by § 717; openings are covered under § 716.

If a wall is labeled a “fire partition” in the plans, do I still need to check smoke barrier rules?

Yes. The label does not relieve you from meeting smoke movement/control requirements where the occupancy or code requires a smoke barrier or where the wall is functioning as a smoke barrier; check both § 708 (fire partitions) and § 709 (smoke barriers) and the applicable occupancy provisions.

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Related in the CBC

When is a fire wall required and how must it be constructed/continued?

How to design and apply fire barriers (ratings, continuity, penetrations)

Protection of floor/roof assemblies, vertical openings and shaft enclosures

Fire Walls, Fire Barriers, Partitions, Shafts & Vertical Openings

California Building Code