CBC · California Building Code

What are the requirements for fire‑resistant joint systems and concealed voids?

The CBC requires joints and concealed voids in fire‑rated walls, floors and roofs to be protected so fire and hot gases cannot pass through; listed joint systems or approved materials must be installed continuously per the manufacturer’s instructions and listing, and joint systems must meet specified test standards and exceptions in §§ 715, 715.1 and 715.2.

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Last reviewed: July 5, 2026

What the code requires — 2-4 sentences

The CBC requires that joints and voids in or between horizontal and vertical assemblies be protected so they resist passage of fire and hot gases for at least the fire‑resistance rating of the assembly in which they occur (see § 715 and § 715.3). Listed joint systems and approved materials must be installed for their full length and in accordance with the manufacturer’s installation instructions and listing criteria (see § 715.2, § 715.2.1 and § 715.2.2). Specific rules and exceptions apply for curtain wall perimeters, intersections of rated assemblies and testing criteria for joint systems (§ 715.3.1, § 715.4).

Requirements in detail

Scope / general rule

  • § 715 governs protection of joints and voids in or between horizontal and vertical assemblies; the purpose is to prevent passage of fire and hot gases through joints or concealed voids.

Installation requirements (how the protection must be installed)

  • Listed joint systems, perimeter fire containment systems and continuity head‑of‑wall systems must be securely installed in accordance with the manufacturer’s instructions and the listing criteria, and must protect the joint or void for its entire length so they are not dislodged or impaired by expected building movement (§ 715.2.1).
  • Approved materials used to protect voids (when a listed system is not used) must likewise be securely installed per manufacturer instructions for the entire length of the void (§ 715.2.2).

Protection level required

  • Joints in or between fire‑resistance‑rated walls, floors (and floor/ceiling assemblies), and roofs shall be protected by an approved fire‑resistant joint system designed to resist fire for not less than the required fire‑resistance rating of the adjacent assembly (§ 715.3).

Test standards and test exposure rules

  • Fire‑resistant joint systems must be tested to ASTM E1966 or UL 2079 (§ 715.3.1). For nonsymmetrical wall joint systems, tests are required with both faces exposed and the assigned rating is the shorter result unless the building official accepts evidence otherwise (§ 715.3.1).
  • For exterior walls with a horizontal fire separation distance greater than 10 ft, the joint system need only be tested for interior fire exposure (§ 715.3.1, Exception).

Curtain wall perimeter / void intersections

  • Voids at the intersection of exterior curtain wall assemblies and fire‑resistance‑rated floor or floor/ceiling assemblies must be protected with an approved perimeter fire containment system that provides an F‑rating at least equal to the fire‑resistance rating of the floor assembly (§ 715.4). Perimeter systems are tested to ASTM E2307 (§ 715.4.1).
  • Where the floor assembly is non‑rated, the void shall be filled with an approved material or system to retard interior spread of fire and hot gases (§ 715.5).

Concealed voids at intersections with nonrated assemblies

  • Voids at intersections of fire barriers with nonfire‑resistance‑rated roof sheathing/slab/deck above must be filled with approved material or protected by an approved continuity head‑of‑wall system tested to ASTM E2837 to provide an F/T rating not less than the fire barrier’s required rating (§ 715.6).

Installation quality and permanence

  • Whether using a listed system or approved material, installation must prevent dislodgement and maintain ability to accommodate expected building movement while resisting the passage of fire and hot gases—i.e., continuous installation for entire length of the joint or void is required (§ 715.2.1, § 715.2.2).

Decision‑relevant numeric dimensions and values (quick reference table)

Topic / dimension Value or requirement Code reference
Must resist fire for same time as adjacent rated assembly Not less than the required fire‑resistance rating of that wall, floor or roof § 715.3
Listed joint system fire test standards ASTM E1966 or UL 2079 § 715.3.1
Perimeter fire containment test standard ASTM E2307 § 715.4.1
Exception—control joint maximum width (no fire‑resistant joint required) ≤ 0.625 in (15.9 mm), tested in accordance with ASTM E119 or UL 263 § 715.3 Exception 9
Testing exposure exception for exterior walls If horizontal fire separation distance > 10 ft, test may be interior exposure only § 715.3.1 Exception
L‑rating limit for joints/voids in smoke barriers (air leakage) ≤ 5 cfm/ft at 0.30 in. w.g. for both ambient and elevated tests § 715.9

Exceptions & special cases

  • The code lists multiple exceptions where a fire‑resistant joint system is not required (examples include floors within a single dwelling unit; floors protected by shaft enclosures in § 713; mezzanine floors; certain parking garage ramps; walls permitted unprotected openings; most exterior curtain wall/roof slab intersections). See the ten exceptions listed in § 715.3 for the full list.
  • Exterior curtain wall/floor intersections where vision glass extends to finished floor may be protected with an approved material (subject to an ASTM E119 exposure/ignition performance requirement) instead of full perimeter containment (§ 715.4 Exception).
  • For smoke barriers, joint systems and perimeter containment systems must also meet UL 2079 air‑leakage criteria and the L‑rating requirement in § 715.9.

Common mistakes

  • Installing a listed joint product but not following the manufacturer’s instructions or the listing details (e.g., not filling the full length of the joint or not allowing required clearances for movement). The code requires secure, full‑length installation per § 715.2.1 and § 715.2.2.
  • Treating every curtain wall/floor gap the same: perimeter fire containment is required for rated floors (§ 715.4), but different rules apply for nonrated floors (§ 715.5) and specific exceptions (e.g., single dwelling unit floors). Verify which subsection applies before choosing a protection method.
  • Using control joints that exceed the narrow control‑joint exemption width (0.625 in) expecting them to be exempt—joints wider than this generally require a listed fire‑resistant system (§ 715.3 Exception 9).
  • Overlooking required testing standards—listed systems must be tested per ASTM E1966 or UL 2079; perimeter systems per ASTM E2307 (§ 715.3.1, § 715.4.1). Using products without appropriate test evidence or listing risks rejection.

Worked example

Scenario: You have a 2‑hour fire‑rated floor/ceiling assembly intersecting an exterior curtain wall. The joint between the curtain wall and the floor creates a continuous perimeter void around the floor.

  1. Code requirement: Protect the void with an approved perimeter fire containment system that provides an F‑rating not less than the floor’s fire‑resistance rating (i.e., 2 hours) (§ 715.4).
  2. Product selection: Choose a perimeter fire containment system with an ASTM E2307 test report showing an F‑rating of 2 hours (or greater) when installed as listed (§ 715.4.1).
  3. Installation: Install the listed system continuously around the entire perimeter void per the manufacturer’s instructions and the listing criteria so it cannot be dislodged and will accommodate expected movement (§ 715.2.1). Document the installation per the listing.
  4. Special checks: If the building is an exterior wall with a horizontal fire separation distance > 10 ft and the product’s test exposure is relevant, confirm whether interior‑exposure testing applies per § 715.3.1 Exception (may reduce required exposure test).

Related provisions

  • § 715 — Joints and voids (general scope and requirements)
  • § 715.1 — General (governs materials and methods for protecting joints and voids)
  • § 715.2 — Installation requirements (listed systems and approved materials)
  • § 715.3 / § 715.3.1 — Fire‑resistance‑rated assembly intersections; test criteria (ASTM E1966 or UL 2079)
  • § 715.4 / § 715.4.1 — Exterior curtain wall / fire‑rated floor intersections; perimeter fire containment and ASTM E2307 testing
  • § 715.5 — Exterior curtain wall / nonfire‑resistance‑rated floor intersections (approved materials to retard fire/hot gas spread)
  • § 715.6 — Fire barrier / nonfire‑rated roof intersections (ASTM E2837 continuity systems)
  • § 715.9 — Joints and voids in smoke barriers (UL 2079 air leakage L‑rating limit)
  • § 714 — Penetrations (related protection for penetrations)
  • § 1705.A.18 — Special inspection requirements for fire‑resistant penetrations and joints in higher‑risk buildings (inspection standards referenced)

Code references

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

  • CBC § 715.3.1 High relevance — show source text

    715.3.1 Fire test criteria. Fire-resistant joint systems shall be tested in accordance with the requirements of either ASTM E1966 or UL 2079. Nonsymmetrical wall joint systems shall be tested with both faces exposed to the furnace, and the assigned fire-resistance rating shall be the shortest duration obtained from the two tests. Where evidence is furnished to show that the wall was tested with the least fire-resistant side exposed to the furnace, subject to acceptance of the building official, the wall need not be subjected to tests from the opposite side.

    Exception: For exterior walls with a horizontal fire separation distance greater than 10 feet (3048 mm), the joint system shall be required to be tested for interior fire exposure only.

    715.4 Exterior curtain wall/fire-resistance-rated floor intersections. Voids created at the intersection of exterior curtain wall assemblies and fire-resistance-rated floor or floor/ceiling assemblies shall be protected with an approved perimeter fire contain

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    ment system to prevent the interior spread of fire. Such systems shall provide an F rating for a time period not less than the fireresistance rating of the floor or floor/ceiling assembly.

    Exceptions: An approved perimeter fire containment system shall not be required for voids in the following locations:

    1. Floors within a single dwelling unit.

    2. Floors and ramps within parking garages or structures constructed in accordance with Sections 406.5 and 406.6.

    3. Mezzanine floors.

    715.4.1 Fire test criteria. Perimeter fire containment systems shall be tested in accordance with the requirements of ASTM E2307.

    Exception: Voids created at the intersection of the exterior curtain wall assemblies and floor assemblies where the vision glass extends to the finished floor level shall be permitted to be protected with an approved material to prevent the interior spread of fire. Such material shall be securely installed and capable of preventing the passage of flame and hot gases sufficient to ignite cotton waste where subjected to ASTM E119 time-temperature fire conditions under a minimum positive pressure differential of 0.01 inch of water (2.49 Pa) for the time period not less than the fire-resistance rating of the floor assembly.

    715.5 Exterior curtain wall/nonfire-resistance-rated floor assembly intersections. Voids created at the intersection of exterior curtain wall assemblies and nonfire-resistance-rated floor or floor/ceiling assemblies shall be filled with an approved material or system to retard the interior spread of fire and hot gases.

    Exceptions: An approved material or system to retard the interior spread of fire and hot gases shall not be required for voids in the following locations:

    1. Floors within a single dwelling unit.

    2. Floors and ramps within parking garages or structures constructed in accordance with Sections 406.5 and 406.6.

    3. Mezzanine floors.

    715.6 Fire barrier/nonfire-resistance-rated roof assembly intersections. Voids created at the intersection of a fire barrier and the underside of a nonfire-resistance-rated roof sheathing, slab or deck above shall be filled by an approved material or system to retard the passage of fire and hot gases, or shall be protected by an approved continuity head-of-wall system tested in accordance with ASTM E2837 to provide an F rating/T rating for a time period not less than the required fire-resistance rating of the fire barrier in which it is installed.

  • CBC § 715.2.2 High relevance — show source text

    715.2.2 Approved materials installation. Approved materials protecting voids shall be securely installed in accordance with the manufacturer’s installation instructions in or on the void for its entire length so as not to dislodge, loosen or otherwise impair its ability to accommodate expected building movements and to resist the passage of fire and hot gases.

    715.3 Fire-resistance-rated assembly intersections. Joints installed in or between fire-resistance-rated walls, floor or floor/ceiling assemblies and roofs or roof/ceiling assemblies shall be protected by an approved fire-resistant joint system designed to resist the passage of fire for a time period not less than the required fire-resistance rating of the wall, floor or roof in or between which the system is installed.

    Exception: Fire-resistant joint systems shall not be required for joints in the following locations:

    1. Floors within a single dwelling unit.
    2. Floors where the joint is protected by a shaft enclosure in accordance with Section 713.
    3. Floors within atriums where the space adjacent to the atrium is included in the volume of the atrium for smoke control

    purposes.

    1. Floors within malls.

    2. Floors and ramps within parking garages or structures constructed in accordance with Sections 406.5 and 406.6.

    3. Mezzanine floors.

    4. Walls that are permitted to have unprotected openings.

    5. Roofs where openings are permitted.

    6. Control joints not exceeding a maximum width of 0.625 inch (15.9 mm) and tested in accordance with ASTM E119 or UL 263.

    7. The intersection of exterior curtain wall assemblies and the roof slab or roof deck.

    715.3.1 Fire test criteria. Fire-resistant joint systems shall be tested in accordance with the requirements of either ASTM E1966 or UL 2079. Nonsymmetrical wall joint systems shall be tested with both faces exposed to the furnace, and the assigned fire-resistance rating shall be the shortest duration obtained from the two tests. Where evidence is furnished to show that the wall was tested with the least fire-resistant side exposed to the furnace, subject to acceptance of the building official, the wall need not be subjected to tests from the opposite side.

    Exception: For exterior walls with a horizontal fire separation distance greater than 10 feet (3048 mm), the joint system shall be required to be tested for interior fire exposure only.

    715.4 Exterior curtain wall/fire-resistance-rated floor intersections. Voids created at the intersection of exterior curtain wall assemblies and fire-resistance-rated floor or floor/ceiling assemblies shall be protected with an approved perimeter fire contain

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    ment system to prevent the interior spread of fire. Such systems shall provide an F rating for a time period not less than the fireresistance rating of the floor or floor/ceiling assembly.

    Exceptions: An approved perimeter fire containment system shall not be required for voids in the following locations:

    1. Floors within a single dwelling unit.

    2. Floors and ramps within parking garages or structures constructed in accordance with Sections 406.5 and 406.6.

    3. Mezzanine floors.

    715.4.1 Fire test criteria. Perimeter fire containment systems shall be tested in accordance with the requirements of ASTM E2307.

  • CBC § 0.01 High relevance — show source text

    Exception: Voids created at the intersection of the exterior curtain wall assemblies and floor assemblies where the vision glass extends to the finished floor level shall be permitted to be protected with an approved material to prevent the interior spread of fire. Such material shall be securely installed and capable of preventing the passage of flame and hot gases sufficient to ignite cotton waste where subjected to ASTM E119 time-temperature fire conditions under a minimum positive pressure differential of 0.01 inch of water (2.49 Pa) for the time period not less than the fire-resistance rating of the floor assembly.

    715.5 Exterior curtain wall/nonfire-resistance-rated floor assembly intersections. Voids created at the intersection of exterior curtain wall assemblies and nonfire-resistance-rated floor or floor/ceiling assemblies shall be filled with an approved material or system to retard the interior spread of fire and hot gases.

    Exceptions: An approved material or system to retard the interior spread of fire and hot gases shall not be required for voids in the following locations:

    1. Floors within a single dwelling unit.

    2. Floors and ramps within parking garages or structures constructed in accordance with Sections 406.5 and 406.6.

    3. Mezzanine floors.

    715.6 Fire barrier/nonfire-resistance-rated roof assembly intersections. Voids created at the intersection of a fire barrier and the underside of a nonfire-resistance-rated roof sheathing, slab or deck above shall be filled by an approved material or system to retard the passage of fire and hot gases, or shall be protected by an approved continuity head-of-wall system tested in accordance with ASTM E2837 to provide an F rating/T rating for a time period not less than the required fire-resistance rating of the fire barrier in which it is installed.

    715.7 Exterior wall/vertical fire barrier intersections. Voids created at the intersection of nonfire-resistance-rated exterior wall assemblies and vertical fire barriers shall be filled with an approved material or system to retard the interior spread of fire and hot

    gases.

    715.8 Curtain wall spandrels. Height and fire-resistance requirements for curtain wall spandrels shall comply with Section 705.9.5. Where Section 705.9.5 does not require fire-resistance-rated curtain wall spandrels, the requirements of Sections 715.4 and 715.5 shall still apply to the intersection between the curtain wall spandrels and the floor.

    715.9 Joints and voids in smoke barriers. Fire-resistant joint systems protecting joints in smoke barriers, and perimeter fire containment systems protecting voids at the intersection of a horizontal smoke barrier and an exterior curtain wall, shall be tested in accordance with the requirements of UL 2079 for air leakage. The L rating of the joint system shall not exceed 5 cubic feet per minute per linear foot (0.00775 m [3] /s m) of joint at 0.30 inch of water (74.7 Pa) for both the ambient temperature and elevated temperature

    tests.

    SECTION 716—OPENING PROTECTIVES

    716.1 General. Opening protectives required by other sections of this code shall comply with the provisions of this section and shall be installed in accordance with NFPA 80.

  • CBC § 715.7 High relevance — show source text

    715.7 Exterior wall/vertical fire barrier intersections. Voids created at the intersection of nonfire-resistance-rated exterior wall assemblies and vertical fire barriers shall be filled with an approved material or system to retard the interior spread of fire and hot

    gases.

    715.8 Curtain wall spandrels. Height and fire-resistance requirements for curtain wall spandrels shall comply with Section 705.9.5. Where Section 705.9.5 does not require fire-resistance-rated curtain wall spandrels, the requirements of Sections 715.4 and 715.5 shall still apply to the intersection between the curtain wall spandrels and the floor.

    715.9 Joints and voids in smoke barriers. Fire-resistant joint systems protecting joints in smoke barriers, and perimeter fire containment systems protecting voids at the intersection of a horizontal smoke barrier and an exterior curtain wall, shall be tested in accordance with the requirements of UL 2079 for air leakage. The L rating of the joint system shall not exceed 5 cubic feet per minute per linear foot (0.00775 m [3] /s m) of joint at 0.30 inch of water (74.7 Pa) for both the ambient temperature and elevated temperature

    tests.

    SECTION 716—OPENING PROTECTIVES

    716.1 General. Opening protectives required by other sections of this code shall comply with the provisions of this section and shall be installed in accordance with NFPA 80.

    TABLE 716.1(1)—MARKING FIRE-RATED GLAZING ASSEMBLIES Col2 Col3
    FIRE TEST STANDARD MARKING DEFINITION OF MARKING
    ASTM E119 or UL 263 W Meets wall assembly criteria.
    ASTM E119 or UL 263 FC Meets floor/ceiling criteriaa
    NFPA 257 or UL 9 OH Meets fire window assembly criteria including the hose stream test.
    NFPA 252 or UL 10B or UL 10C D Meets fire door assembly criteria.
    NFPA 252 or UL 10B or UL 10C H Meets fire door assembly hose stream test.
    NFPA 252 or UL 10B or UL 10C T Meets 450°F temperature rise criteria for 30 minutes
    — XXX The time in minutes of the fire resistance or fire protection rating of the glazing assembly.
    For SI:°C = [(°F) – 32]/1.8.
    a. See Section 2409.1    		 For SI:°C = [(°F) – 32]/1.8.
    a. See Section 2409.1    		 For SI:°C = [(°F) – 32]/1.8.
    a. See Section 2409.1

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    |TABLE 716.1(2)—OPENING FIRE PROTECTION ASSEMBLIES,

  • CBC § 714.6 High relevance — show source text

    714.6 Nonfire-resistance-rated assemblies. Penetrations of nonfire-resistance-rated floor or floor/ceiling assemblies or the ceiling membrane of a nonfire-resistance-rated roof/ceiling assembly shall meet the requirements of Section 713 or shall comply with Section 714.6.1 or 714.6.2.

    714.6.1 Noncombustible penetrating items. Noncombustible penetrating items that connect not more than five stories are permitted, provided that the annular space is filled to resist the free passage of flame and the products of combustion with an approved noncombustible material or with a fill, void or cavity material that is tested and classified for use in through-penetration firestop systems.

    714.6.2 Penetrating items. Penetrating items that connect not more than two stories are permitted, provided that the annular space is filled with an approved material to resist the free passage of flame and the products of combustion.

    SECTION 715—JOINTS AND VOIDS

    715.1 General. The provisions of this section shall govern the materials and methods of construction used to protect joints and voids in or between horizontal and vertical assemblies.

    715.2 Installation. Systems or materials protecting joints and voids shall be installed in accordance with Sections 715.2.1 and 715.2.2.

    715.2.1 List system installation. Listed fire-resistant joint systems, perimeter fire containment systems and continuity head-ofwall systems shall be securely installed in accordance with the manufacturer’s installation instructions and the listing criteria in or on the joint or void for its entire length so as not to dislodge, loosen or otherwise impair its ability to accommodate expected building movements and to resist the passage of fire and hot gases.

    715.2.2 Approved materials installation. Approved materials protecting voids shall be securely installed in accordance with the manufacturer’s installation instructions in or on the void for its entire length so as not to dislodge, loosen or otherwise impair its ability to accommodate expected building movements and to resist the passage of fire and hot gases.

    715.3 Fire-resistance-rated assembly intersections. Joints installed in or between fire-resistance-rated walls, floor or floor/ceiling assemblies and roofs or roof/ceiling assemblies shall be protected by an approved fire-resistant joint system designed to resist the passage of fire for a time period not less than the required fire-resistance rating of the wall, floor or roof in or between which the system is installed.

    Exception: Fire-resistant joint systems shall not be required for joints in the following locations:

    1. Floors within a single dwelling unit.
    2. Floors where the joint is protected by a shaft enclosure in accordance with Section 713.
    3. Floors within atriums where the space adjacent to the atrium is included in the volume of the atrium for smoke control

    purposes.

    1. Floors within malls.

    2. Floors and ramps within parking garages or structures constructed in accordance with Sections 406.5 and 406.6.

    3. Mezzanine floors.

    4. Walls that are permitted to have unprotected openings.

    5. Roofs where openings are permitted.

    6. Control joints not exceeding a maximum width of 0.625 inch (15.9 mm) and tested in accordance with ASTM E119 or UL 263.

    7. The intersection of exterior curtain wall assemblies and the roof slab or roof deck.

  • CBC § 17.1 High relevance — show source text

    [BF] 1705 A .16 Intumescent fire-resistive materials. Special inspections and tests for intumescent fire-resistive materials applied to structural elements and decks shall be performed in accordance with AWCI 12-B. Special inspections and tests shall be based on the fire-resistance design as designated in the approved construction documents. Special inspections and tests shall be performed during construction. Additional visual inspection shall be performed after the rough installation and, where applicable, prior to the concealment of electrical, automatic sprinkler, mechanical and plumbing systems.

    [BF] 1705 A .17 Exterior insulation and finish systems (EIFS). Special inspections shall be required for all EIFS applications.

    Exceptions:

    1. Special inspections shall not be required for EIFS applications installed over a water-resistive barrier with a means of draining moisture to the exterior.
    2. Special inspections shall not be required for EIFS applications installed over masonry or concrete walls.

    [BF] 1705 A .17.1 Water-resistive barrier coating. A water-resistive barrier coating complying with ASTM E2570 requires special inspection of the water-resistive barrier coating where installed over a sheathing substrate.

    [BF] 1705 A .18 Fire-resistant penetrations and joints. In high-rise buildings, in buildings assigned to Risk Category III or IV, or in fire areas containing Group R occupancies with an occupant load greater than 250, special inspections for through-penetrations, membrane penetration firestops, fire-resistant joint systems and perimeter fire containment systems that are tested and listed in accordance with Sections 714.4.1.2, 714.5.1.2, 715.3.1 and 715.4 shall be in accordance with Section 1705 A .18.1 or 1705 A .18.2.

    [DSA SS, DSA-SS/CC] Buildings assigned to Risk Category II, III or IV shall be subject to special inspections for fire-resistant penetrations and joints.

    [BF] 1705 A .18.1 Penetration firestops. Inspections of penetration firestop systems that are tested and listed in accordance with Sections 714.4.1.2 and 714.5.1.2 shall be conducted by an approved agency in accordance with ASTM E2174.

    [BF] 1705 A .18.2 Fire-resistant joint systems. Inspection of fire-resistant joint systems that are tested and listed in accordance with Sections 715.3.1 and 715.4 shall be conducted by an approved agency in accordance with ASTM E2393.

    [F] 1705 A .19 Testing for smoke control. Smoke control systems shall be tested by a special inspector.

    [F] 1705 A .19.1 Testing scope. The test scope shall be as follows:

    1. During erection of ductwork and prior to concealment for the purposes of leakage testing and recording of device location.

    2. Prior to occupancy and after sufficient completion for the purposes of pressure difference testing, flow measurements and detection and control verification.

    [F] 1705 A .19.2 Qualifications. Approved agencies for smoke control testing shall have expertise in fire protection engineering, mechanical engineering and certification as air balancers.

  • CBC § 3114.6 High relevance — show source text

    3114.6 Roof assemblies. Intermodal shipping container roof assemblies shall comply with the applicable requirements of Chapter 15.

    Exception: Single-unit, stand-alone intermodal shipping containers not attached to, or stacked vertically over, other intermodal shipping containers, buildings or structures. [DSA-SS & DSA-SS/CC] Not permitted by DSA.

    3114.7 Joints and voids. Joints and voids that create concealed spaces between connected or stacked intermodal shipping containers at fire-resistance-rated walls, floor or floor/ceiling assemblies and roofs or roof/ceiling assemblies shall be protected by an approved fire-resistant joint system in accordance with Section 715.

    3114.8 Structural. Intermodal shipping containers that conform to ISO 1496-1 and are repurposed for use as buildings or structures, or as a part of buildings or structures, shall be designed in accordance with Chapter 16 and this section.

    3114.8.1 Foundations and supports. Intermodal shipping containers repurposed for use as a permanent building or structure shall be supported on foundations or other supporting structures designed and constructed in accordance with Chapters 16 through 23.

    3114.8.1.1 Anchorage. Intermodal shipping containers shall be anchored to foundations or other supporting structures as necessary to provide a continuous load path for all applicable design and environmental loads in accordance with Chapter 16.

    3114.8.1.2 Stacking. Intermodal shipping containers used to support stacked units shall comply with Section 3114.8.4.

    3114.8.2 Welds. The strength of new welds and connections shall be of not less than the strength provided by the original connections. All new welds and connections shall be designed and constructed in accordance with Chapters 16, 17 and 22.

    3114.8.3 Structural design. The structural design for the intermodal shipping containers repurposed for use as a building or structure, or as part of a building or structure, shall comply with Section 3114.8.4 or 3114.8.5.

    3114.8.4 Detailed design procedure. A structural analysis meeting the requirements of this section shall be provided to the building official to demonstrate the structural adequacy of the intermodal shipping containers.

    Exception: Structures using an intermodal shipping container designed in accordance with Section 3114 8.5.

    3114.8.4.1 Material properties. Structural material properties for existing intermodal shipping container steel components shall be established by Section 2202.

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    SPECIAL CONSTRUCTION

  • CBC § 4.3. High relevance — show source text

    4.3. In hurricane-prone regions and flood hazard areas, such units are designed in accordance with the applicable provisions of Chapter 16. 5. [HCD] Shipping containers constructed or converted off-site that meet the definition of Factory-built Housing in Health and Safety Code Section 19971 or Commercial Modular(s) as defined in Health and Safety Code Section 18001.8 shall be approved by the Department of Housing and Community Development.

    3114.2 Construction documents. The construction documents shall contain information to verify the dimensions and establish the physical properties of the steel components and wood floor components of the intermodal shipping container, in addition to the information required by Sections 107 and 1603.

    3114.3 Intermodal shipping container information. Intermodal shipping containers shall bear an existing data plate containing the following information as required by ISO 6346 and verified by an approved agency. A report of the verification process and findings shall be provided to the building owner.

    1. Manufacturer’s name or identification number.

    2. Date manufactured.

    3. Safety approval number.

    4. Identification number.

    5. Maximum operating gross mass or weight (kg) (lbs).

    6. Allowable stacking load for 1.8G (kg) (lbs).

    7. Transverse racking test force (Newtons).

    8. Valid maintenance examination date.

    Where approved by the building official, the markings and existing data plate are permitted to be removed from the intermodal shipping containers before they are repurposed for use as buildings or structures or as a part of buildings or structures.

    3114.4 Protection against decay and termites. Wood structural floors of intermodal shipping containers shall be protected from decay and termites in accordance with the applicable provisions of Section 2304.12.1.1.

    3114.5 Under-floor ventilation. The space between the bottom of the floor joists and the earth under any intermodal shipping container, except spaces occupied by basements and cellars, shall be provided with ventilation in accordance with Section 1202.4.

    3114.6 Roof assemblies. Intermodal shipping container roof assemblies shall comply with the applicable requirements of Chapter 15.

    Exception: Single-unit, stand-alone intermodal shipping containers not attached to, or stacked vertically over, other intermodal shipping containers, buildings or structures. [DSA-SS & DSA-SS/CC] Not permitted by DSA.

    3114.7 Joints and voids. Joints and voids that create concealed spaces between connected or stacked intermodal shipping containers at fire-resistance-rated walls, floor or floor/ceiling assemblies and roofs or roof/ceiling assemblies shall be protected by an approved fire-resistant joint system in accordance with Section 715.

    3114.8 Structural. Intermodal shipping containers that conform to ISO 1496-1 and are repurposed for use as buildings or structures, or as a part of buildings or structures, shall be designed in accordance with Chapter 16 and this section.

    3114.8.1 Foundations and supports. Intermodal shipping containers repurposed for use as a permanent building or structure shall be supported on foundations or other supporting structures designed and constructed in accordance with Chapters 16 through 23.

    3114.8.1.1 Anchorage. Intermodal shipping containers shall be anchored to foundations or other supporting structures as necessary to provide a continuous load path for all applicable design and environmental loads in accordance with Chapter 16.

    3114.8.1.2 Stacking. Intermodal shipping containers used to support stacked units shall comply with Section 3114.8.4.

  • 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.

    2025 CALIFORNIA FIRE CODE 7-1

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    7-2 2025 CALIFORNIA FIRE CODE

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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 § 1023.3.1. High relevance — show source text

    1. Openings shall not be limited to 156 square feet (15 m [2] ) or an aggregate width of 25 percent of the length of the wall where the opening protective is a fire door assembly in a fire barrier separating an enclosure for exit access stairways and ramps, and interior exit stairways and ramps from an exit passageway in accordance with Section 1023.3.1.

    2. Openings providing entrance to an elevator car shall not be limited to 156 square feet (15 m [2] ) or an aggregate width of 25 percent of the length of the wall where the opening protective is a fire door assembly in a fire barrier that is an elevator hoistway enclosure.

    3. Openings shall not be limited to an aggregate width of 25 percent of the length of the wall where opening serves a shaft enclosure in accordance with Section 713.

    4. Openings shall not be limited to an aggregate width of 25 percent of the length of the wall where opening serves a chute access room in accordance with Section 713.13.3 or a chute discharge room in accordance with Section 713.13.4.

    707.7 Penetrations. Penetrations of fire barriers shall comply with Section 714.

    707.7.1 Prohibited penetrations. Penetrations into enclosures for shafts, interior exit stairways and ramps, and exit passageways shall be allowed only where permitted by Sections 713.8.1, 1023.5 and 1024.6, respectively.

    707.8 Joints. Joints made in or between fire barriers, and joints made at the intersection of fire barriers with the underside of a fireresistance-rated floor or roof sheathing, slab or deck above, and with other fire-resistance-rated wall assemblies shall comply with Section 715.

    707.9 Voids at intersections. The voids created at the intersection of a fire barrier and a nonfire-resistance-rated roof assembly or a nonfire-resistance-rated exterior wall assembly shall comply with Section 715.

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

    SECTION 708—FIRE PARTITIONS

    708.1 General. The following wall assemblies shall comply with this section:

    1. Separation walls as required by Section 420.2 for Group R occupancies.

    2. Walls separating tenant spaces in covered and open mall buildings as required by Section 402.4.2.1.

    3. Corridor walls as required by Section 1020.2 and in Group I-2 as required by Section 407.3.

    4. Enclosed elevator lobby separation as required by Section 3006.3.

    5. Egress balconies as required by Section 1021.2

    6. Walls separating ambulatory care facilities from adjacent spaces, corridors or tenants as required by Section 422.2.

    7. Walls separating dwelling and sleeping units in Groups R-1 and R-2 in accordance with Sections 907.2.8.1 and 907.2.9.1.

    8. Vestibules in accordance with Section 1028.2.

    9. Walls separating enclosed tenant spaces in high-rise buildings and in buildings of Types I, IIA, IIIA, IV or VA construction of Group A, E, H, I, L and R-2.1 occupancies and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal.

    708.2 Materials. The walls shall be of materials permitted by the building type of construction.

  • CBC § 712.1.3.1 High relevance — show source text

    712.1.3.1 Opening size. Protection by a draft curtain and closely spaced sprinklers in accordance with NFPA 13 shall be permitted where the area of the vertical opening between stories does not exceed twice the horizontal projected area of the escalator. In other than Groups B and M, this application is limited to openings that do not connect more than four stories.

    712.1.3.2 Automatic shutters. Protection of the vertical opening by listed or approved shutters at every penetrated floor shall be permitted in accordance with all of the following:

    1. The shutter shall be installed in accordance with the manufacturer’s instructions.

    2. The shutter shall be of noncombustible construction and have a fire-resistance rating of not less than 1.5 hours.

    3. The shutter shall close immediately upon the actuation of a smoke detector installed in accordance with Section 907.3.

    4. The shutter shall completely close off the vertical opening.

    5. Escalators shall cease operation when the shutter begins to close.

    6. The shutter shall operate at a speed of not more than 30 feet per minute (152.4 mm/s).

    7. The shutter shall be equipped with a sensing leading edge to stop closure where in contact with any obstacle, and continue to close when the obstacle is cleared.

    712.1.4 Penetrations. Penetrations, concealed and unconcealed, shall be permitted where protected in accordance with Section 714.

    712.1.5 Joints. Joints shall be permitted where complying with Section 712.1.5.1 or 712.1.5.2, as applicable.

    712.1.5.1 Joints in or between horizontal assemblies. Joints made in or between horizontal assemblies shall comply with Section 715. The void created at the intersection of a floor/ceiling assembly and an exterior curtain wall assembly shall be permitted where protected in accordance with Section 715.4.

    712.1.5.2 Joints in or between nonfire-resistance-rated floor assemblies. Joints in or between floor assemblies without a required fire-resistance rating shall be permitted where they comply with one of the following:

    1. The joint shall be concealed within the cavity of a wall.
    2. The joint shall be located above a ceiling.

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    FIRE AND SMOKE PROTECTION FEATURES

    1. The joint shall be sealed, treated or covered with an approved material or system to resist the free passage of flame and the products of combustion.

    Exception: Joints meeting one of the exceptions specified in Section 715.3.

    712.1.6 Ducts and air transfer openings. Penetrations by ducts and air transfer openings shall be protected in accordance with Section 717. Grease ducts shall be protected in accordance with the California Mechanical Code.

    712.1.7 Atriums. Atriums complying with Section 404 that connect two or more stories in Group I-2 or I-3 occupancies or three or more stories in other occupancies shall be permitted.

    Exceptions:

    1. Atriums shall not be permitted within Group H occupancies.
    2. Balconies or stories within Groups A-1, A-4 and A-5 and mezzanines that comply with Section 505 shall not be considered a story as it applies to this section
  • CBC § 501A.3 High relevance — show source text

    501 A .2 Fire-resistance ratings. Fire-resistance ratings shall comply with the California Building Standards Code.

    501A.3 Prescriptive compliance provisions. Alterations, additions and changes of occupancy to the following categories of existing buildings and structures shall comply with the provisions of this section.

    501A.3.1 Prescriptive compliance provisions for SPC-4D using the California Building Code, 1980 (CBC 1980). Nonconforming buildings shall satisfy the following requirements: 1. The California Building Code, 1980 (CBC 1980), as used in this chapter, consists of the Uniform Building Code, 1979 (UBC 1979) along with requirements contained in: a) California Code of Regulations, Title 24- Building Standards, dated February 2, 1980 (Revision record for Register 80, No. 5). b) California Code of Regulations, Title 22 – Social Security, dated October 13, 1979 (Revision Record for Register 79, No 41). c) California Code of Regulations, Title 17 – Public Health, dated October 13, 1979 (Revision Record for Register 79, No 41-B). 2. All existing structural elements of Seismic Force Resisting System (SFRS) shall satisfy the detailing requirements in the CBC 1980 or demonstrate that the level of seismic performance is equivalent to that given in the CBC 1980, as determined by the building official. 3. A continuous load path or paths with adequate strength and stiffness to transfer all the forces from the point of origin to final point of resistance shall be justified by analysis. 4. Site data report in accordance with the CBC 1980 shall establish that seismically induced differential settlement does not exceed 1 ″ in 40 ′ .

    5. Adjacent buildings shall satisfy the SPC building separation requirements in accordance with the California Administrative Code, Chapter 6 Section 3.4. 6. The addition of new structural elements or strengthening of existing structural elements for retrofit of nonconforming build- ings to SPC-4D shall comply with the following: a) The seismic demand (forces or displacements) shall be in accordance with the CBC 1980; b) Capacity, detailing and connections for new structural elements shall satisfy the requirements in the CBC 2025 for new construction; and c) The strengthening of existing structural elements shall use capacities determined in accordance with the CBC 2025 for new construction consistent with the detailing and connections used in the strengthened member. 7. All construction, quality assurance and quality control shall be in accordance with the new construction provisions of CBC 2025.

    8. Elements not part of the Seismic Force-Resisting System (SFRS), including those identified in the California Administrative Code Chapter 6, Article 10, shall be evaluated using seismic forces and the requirements of the CBC 1980. 9. Any column or wall that forms part of two or more intersecting SFRS and is subjected to axial load due to seismic forces acting along either principal plan axis equaling or exceeding 20 percent of the axial design strength of the column or wall shall be _evaluated for the most critical load effect due to application of seismic force in any direction.

Frequently asked questions

Do all joints in a fire‑rated wall require a listed joint system?

Not always — joints in fire‑resistance‑rated assemblies generally require an approved fire‑resistant joint system that resists fire for the assembly’s required rating (§ 715.3), but the code lists specific exceptions (for example, floors within a single dwelling unit, shaft‑protected floors, control joints ≤ 0.625 in, etc.). See § 715.3 for the full exceptions.

Can I use a generic sealant to fill a perimeter void at a curtain wall?

Only if the material or system is an approved product for that application — voids at curtain wall/fire‑rated floor intersections require a perimeter fire containment system providing an F‑rating at least equal to the floor if the floor is fire‑rated (§ 715.4). For nonrated floors, approved materials that retard fire/gases may be used (§ 715.5).

What tests must a fire‑resistant joint system have?

Joint systems must be tested to ASTM E1966 or UL 2079; perimeter fire containment systems use ASTM E2307. Nonsymmetrical wall joint systems generally require testing from both faces (§ 715.3.1, § 715.4.1).

How must a listed joint system be installed?

A listed system must be securely installed in accordance with the manufacturer’s installation instructions and the conditions of the listing for the entire length of the joint or void so it won’t be dislodged and will accommodate expected movement (§ 715.2.1).

Are there air‑leakage limits for joints in smoke barriers?

Yes. Joint systems protecting smoke barriers must be tested for air leakage per UL 2079 and have an L‑rating not exceeding 5 cfm/ft at 0.30 in. w.g. for both ambient and elevated temperature tests (§ 715.9).

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