Openings, Penetrations, Joints & Duct/Air Transfer Protection

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

• CBC § 717.5.6 High relevance — show source text

  Exception: Smoke dampers are not required where the openings in ducts are limited to a single smoke compartment and the ducts are constructed of steel. � 717.5.6 Exterior walls. Ducts and air transfer openings in fire-resistance-rated exterior walls required to have protected openings in accordance with Section 705.11 shall be protected with listed fire dampers installed in accordance with their listing.

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  FIRE AND SMOKE PROTECTION FEATURES

  717.5.7 Smoke partitions. A listed smoke damper designed to resist the passage of smoke shall be provided at each point that an air transfer opening penetrates a smoke partition. Smoke dampers and smoke damper actuation methods shall comply with Section 717.3.3.2.

  Exception: Where the installation of a smoke damper will interfere with the operation of a required smoke control system in accordance with Section 909, approved alternative protection shall be utilized.

  717.6 Horizontal assemblies. Penetrations by ducts and air transfer openings of a floor, floor/ceiling assembly or the ceiling membrane of a roof/ceiling assembly shall be protected by a shaft enclosure that complies with Section 713 or shall comply with Sections 717.6.1 through 717.6.3.

  717.6.1 Through penetrations. A duct constructed of approved materials in accordance with the California Mechanical Code that penetrates a fire-resistance-rated floor/ceiling assembly that connects not more than two stories is permitted without shaft enclosure protection, provided that a listed fire damper is installed at the floor line or the duct is protected in accordance with Section 714.5. For air transfer openings, see Section 712.1.9.

  Exception: In occupancies other than Groups I-2 and I-3, a duct is permitted to penetrate three floors or less without a fire damper at each floor, provided that such duct meets all of the following requirements:

  1. The duct shall be contained and located within the cavity of a wall and shall be constructed of steel having a minimum wall thickness of 0.0187 inches (0.4712 mm) (No. 26 gage).
  2. The duct shall open into only one dwelling unit or sleeping unit and the duct system shall be continuous from the unit to the exterior of the building.
  3. The duct shall not exceed 4-inch (102 mm) nominal diameter and the total area of such ducts shall not exceed 100 square inches (0.065 m [2] ) in any 100 square feet (9.3 m [2] ) of floor area.
  4. The annular space around the duct is protected with materials that prevent the passage of flame and hot gases sufficient to ignite cotton waste where subjected to ASTM E119 or UL 263 time-temperature conditions under a minimum positive pressure differential of 0.01 inch of water (2.49 Pa) at the location of the penetration for the time period equivalent to the fire-resistance rating of the construction penetrated.
  5. Grille openings located in a ceiling of a fire-resistance-rated floor/ceiling or roof/ceiling assembly shall be protected with a listed ceiling radiation damper installed in accordance with Section 717.6.2.1.
• CBC § 1105.7.3 High relevance — show source text

  1105.7.3 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.

  Exceptions:

  1. Existing wired glass vision panels in doors shall be permitted to remain.
  2. Existing nonlabeled protection plates shall be permitted to remain.

  1105.7.4 Penetrations. Penetrations of smoke barriers shall comply with the California Building Code .

  Exception: Approved existing materials and methods of construction.

  1105.7.5 Joints. Joints made in or between smoke barriers shall comply with the California Building Code .

  Exception: Approved existing materials and methods of construction.

  1105.7.6 Duct and air transfer openings. Penetrations in a smoke barrier by duct and air transfer openings shall comply with Section 717 of the California Building Code .

  Exception: Where existing duct and air transfer openings in smoke barriers exist without smoke dampers, they shall be permitted to remain. Any changes to existing smoke dampers shall be submitted for review and approved in accordance with Section 717 of the California Building Code .

  1105.8 Group I-2 care suites. Care suites in existing Group I-2, Condition 2 occupancies shall comply with Sections 407.4.4 through 407.4.4.7.2 of the California Building Code .

  1105.9 Group I-2 automatic sprinkler system. An automatic sprinkler system installed in accordance with Section 903.3.1.1 shall be provided throughout the floor containing the Group I-2 fire area. The sprinkler system shall be provided throughout the floor where the Group I-2 occupancy is located, on all floors between the Group I-2 occupancy fire area and the level of exit discharge, the level of exit discharge, and all floors below the level of exit discharge.

  Exception: Floors classified as an open parking garage are not required to be sprinklered.

  1105.10 Group I-2 automatic fire alarm system. An automatic fire alarm system shall be installed in existing Group I-2 occupancies in accordance with Section 907.2.6.2.

  Exception: Manual fire alarm boxes in patient sleeping areas shall not be required at exits if located at all nurses’ control stations or other constantly attended staff locations, provided such that manual fire alarm boxes are visible, are provided with ready access, and travel distances required in Section 907.4.2.1 are not exceeded.

  1105.11 Essential electrical systems. Essential electrical systems in Group I-2, Condition 2 occupancies shall be in accordance with Sections 1105.11.1 and 1105.11.2.

  1105.11.1 Where required. Where required by NFPA 99, Group I-2, Condition 2 occupancies shall be provided with an essential electrical system in accordance with NFPA 99.

  1105.11.2 Installation and duration. In Group I-2, Condition 2 occupancies, the installation and duration of operation of existing essential electrical systems shall be based on a hazard vulnerability analysis conducted in accordance with NFPA 99.

• CBC § 717.5.1 High relevance — show source text

  717.5.1 Fire walls. Ducts and air transfer openings permitted in fire walls in accordance with Section 706.11 shall be protected with listed fire dampers installed in accordance with their listing.

  717.5.1.1 Horizontal exits. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a fire wall that serves as a horizontal exit.

  717.5.2 Fire barriers. In other than Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal. Ducts and air transfer openings of fire barriers shall be protected with listed fire dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate enclosures for interior exit stairways and ramps and exit passageways, except as permitted by Sections 1023.5 and 1024.6, respectively.

  Exceptions: Fire dampers are not required at penetrations of fire barriers where any of the following apply:

  1. Penetrations are tested in accordance with ASTM E119 or UL 263 as part of the fire-resistance-rated assembly.
  2. Ducts are used as part of an approved smoke control system in accordance with Section 909 and where the use of a fire damper would interfere with the operation of a smoke control system.
  3. Such walls are penetrated by fully ducted HVAC systems, have a required fire-resistance rating of 1 hour or less, are in areas of other than Group H and are in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2. For the purposes of this exception, a fully ducted HVAC system shall be a duct system for conveying supply, return or exhaust air as part of the structure’s HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous from the air-handling appliance or equipment to the air outlet and inlet terminals. Nonmetal flexible air connectors shall be permitted in the following locations in accordance with Section 603 of the California Mechanical Code: 3.1. At the duct connection to the air handling unit or equipment located within the mechanical room. 3.2. From an overhead metal duct to a ceiling diffuser within the same room.

  [SFM] For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings of fire barriers shall be protected with approved fire and smoke dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate exit enclosures and exit passageways except as permitted by Sections 1023.5 and 1024.6, respectively.

  Exceptions: 1. Fire dampers are not required at penetrations of fire barriers where penetrations are tested in accordance with ASTM E119 as part of the fire-resistance rated assembly.

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  FIRE AND SMOKE PROTECTION FEATURES

• CBC § 713.6 High relevance — show source text

  713.6 Exterior walls. Where exterior walls serve as a part of a required shaft enclosure, such walls shall comply with the requirements of Section 705 for exterior walls and the fire-resistance-rated enclosure 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.

  713.7 Openings. Openings in a shaft enclosure shall be protected in accordance with Section 716 as required for fire barriers. Doors shall be self- or automatic-closing by smoke detection in accordance with Section 716.2.6.6.

  713.7.1 Prohibited openings. Openings other than those necessary for the purpose of the shaft shall not be permitted in shaft enclosures.

  713.8 Penetrations. Penetrations in a shaft enclosure shall be protected in accordance with Section 714 as required for fire barriers or horizontal assemblies or both. Structural elements, such as beams or joists, where protected in accordance with Section 714 shall be permitted to penetrate a shaft enclosure.

  713.8.1 Prohibited penetrations. Penetrations other than those necessary for the purpose of the shaft shall not be permitted in shaft enclosures.

  Exception: Membrane penetrations shall be permitted on the outside of shaft enclosures. Such penetrations shall be protected in accordance with Section 714.4.2.

  713.9 Joints. Joints in a shaft enclosure shall comply with Section 715.

  713.10 Duct and air transfer openings. Penetrations of a shaft enclosure by ducts and air transfer openings shall comply with Section 717.

  713.11 Enclosure at the bottom. Shafts that do not extend to the bottom of the building or structure shall comply with one of the following:

  1. Be enclosed at the lowest level with construction of the same fire-resistance rating as the lowest floor through which the shaft passes, but not less than the rating required for the shaft enclosure.

  2. Terminate in a room having a use related to the purpose of the shaft. The room shall be separated from the remainder of the building by fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 711, or both. The fire-resistance rating and opening protectives shall be not less than the protection required for the shaft enclosure.

  3. Be protected by approved fire dampers installed in accordance with their listing at the lowest floor level within the shaft enclosure.

  Exceptions:

  1. The fire-resistance-rated room separation is not required, provided that the only openings in or penetrations of the shaft enclosure to the interior of the building occur at the bottom. The bottom of the shaft shall be closed off around the penetrating items with materials permitted by Section 718.3.1 for draftstops, or the room shall be provided with an approved automatic sprinkler system.
  2. A shaft enclosure containing a waste or linen chute shall not be used for any other purpose and shall discharge in a room protected in accordance with Section 713.13.4.
  3. The fire-resistance-rated room separation and the protection at the bottom of the shaft are not required provided that there are no combustibles in the shaft and there are no openings or other penetrations through the shaft enclosure to the interior of the building.
• CBC § 3.1. High relevance — show source text

  For the purposes of this exception, a fully ducted HVAC system shall be a duct system for conveying supply, return or exhaust air as part of the structure’s HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous from the air-handling appliance or equipment to the air outlet and inlet terminals. Nonmetal flexible air connectors shall be permitted in the following locations in accordance with Section 603 of the California Mechanical Code: 3.1. At the duct connection to the air handling unit or equipment located within the mechanical room. 3.2. From an overhead metal duct to a ceiling diffuser within the same room.

  [SFM] For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings of fire barriers shall be protected with approved fire and smoke dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate exit enclosures and exit passageways except as permitted by Sections 1023.5 and 1024.6, respectively.

  Exceptions: 1. Fire dampers are not required at penetrations of fire barriers where penetrations are tested in accordance with ASTM E119 as part of the fire-resistance rated assembly.

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  FIRE AND SMOKE PROTECTION FEATURES

  2. Fire and smoke dampers are not required where ducts are used as part of an approved smoke control system in accordance with Section 909 and where the use of a fire or smoke damper would interfere with the operation of a smoke control system.

  717.5.2.1 Horizontal exits. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a fire barrier that serves as a horizontal exit.

  717.5.3 Shaft enclosures. Shaft enclosures that are permitted to be penetrated by ducts and air transfer openings shall be protected with listed fire and smoke dampers installed in accordance with their listing.

  Exceptions:

  1. Fire dampers are not required at penetrations of shafts where any of the following criteria are met: 1.1. Steel exhaust subducts having a wall thickness of not less than 0.0187 inch (0.4712 mm) are extended not less than 22 inches (559 mm) vertically in exhaust shafts, and an exhaust fan is installed at the upper terminus of the shaft that is powered continuously in accordance with Section 909.11, so as to maintain a continuous upward airflow to the outdoors. 1.2. Penetrations are tested in accordance with ASTM E119 or UL 263 as part of the fire-resistance-rated assembly. 1.3. Ducts are used as part of an approved smoke control system designed and installed in accordance with Section 909 and where the fire damper will interfere with the operation of the smoke control system. 1.4. The penetrations are in parking garage exhaust or supply shafts that are separated from other building shafts by not less than 2-hour fire-resistance-rated construction.
• CBC § 710.5.3 High relevance — show source text

  710.5.3 Pass-through openings in Group I-2, Condition 2. Where pass-through openings are provided in smoke partitions in Group I-2, Condition 2 occupancies, such openings shall comply with the following:

  1. The smoke compartment in which the pass-through openings occur does not contain a patient care suite or sleeping

  room.

  2. Pass-through openings are installed in a wall, door or vision panel that is not required to have a fire-resistance rating.
  3. The top of the pass-through opening is located a maximum of 48 inches (1219 mm) above the floor.
  4. The aggregate area of all such pass-through openings within a single room shall not exceed 80 square inches (0.05 m [2] ).

  710.6 Penetrations. The space around penetrating items shall be filled with an approved material to limit the free passage of smoke.

  710.7 Joints. Joints shall be filled with an approved material to limit the free passage of smoke.

  710.8 Ducts and air transfer openings. The space around a duct penetrating a smoke partition shall be filled with an approved material to limit the free passage of smoke. Air transfer openings in smoke partitions shall be provided with a smoke damper complying with Section 717.3.2.2. For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, duct openings in smoke partitions shall also be provided with a smoke damper comply- ing with Section 717.3.2.2.

  Exception s :

  1. Where the installation of a smoke damper will interfere with the operation of a required smoke control system in accordance with Section 909, approved alternative protection shall be utilized. 2. [SFM] Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019- inch (0.40 mm) in thickness and there are no openings serving the corridor.

  SECTION 711—FLOOR AND ROOF ASSEMBLIES

  711.1 General. Horizontal assemblies shall comply with Section 711.2. Nonfire-resistance-rated floor and roof assemblies shall comply with Section 711.3.

  711.2 Horizontal assemblies. Horizontal assemblies shall comply with Sections 711.2.1 through 711.2.6.

  711.2.1 Materials. Assemblies shall be of materials permitted by the building type of construction.

  711.2.2 Continuity. Assemblies shall be continuous without vertical openings, except as permitted by this section and Section 712.

  711.2.3 Supporting construction. The supporting construction shall be protected to afford the required fire-resistance rating of the horizontal assembly supported.

  Exception: In buildings of Type IIB, IIIB or VB construction, the construction supporting the horizontal assembly is not required to be fire-resistance rated at the following:

  1. Horizontal assemblies at the separations of incidental uses as specified by Table 509.1 provided that the required fireresistance rating does not exceed 1 hour.

  2. Horizontal assemblies at the separations of dwelling units and sleeping units as required by Section 420.3.

  3. Horizontal assemblies at smoke barriers constructed in accordance with Section 709.

  711.2.4 Fire-resistance rating. The fire-resistance rating of horizontal assemblies shall comply with Sections 711.2.4.1 through 711.2.4.6 but shall be not less than that required by the building type of construction.

• CBC § 2.1 High relevance — show source text

  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.

  K102.2.5 Joints. Joints made in or between smoke barriers shall comply with the California Building Code .

  Exception: Approved existing materials and methods of construction.

  2025 CALIFORNIA FIRE CODE APPENDIX K-3

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  APPENDIX K—CONSTRUCTION REQUIREMENTS FOR EXISTING AMBULATORY CARE FACILITIES

  K102.2.6 Duct and air transfer openings. Penetrations in a smoke barrier by duct and air-transfer openings shall comply with Section 717 of the California Building Code .

  Exception: Where existing duct and air-transfer openings in smoke barriers exist without smoke dampers, they shall be permitted to remain. Any changes to existing smoke dampers shall be submitted for review and approved in accordance with Section 717 of the California Building Code .

  K102.2.7 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 originated.

  K102.3 Automatic sprinkler system. An automatic sprinkler system shall be provided in ambulatory care facilities where required by Sections K102.3.1 and K102.3.2.

  K102.3.1 Types IIB, IIIB and VB construction. An automatic sprinkler system shall be provided throughout the entire floor containing an ambulatory care facility in Type IIB, IIIB and VB construction where either of the following conditions exist at any time:

  1. Four or more care recipients are rendered incapable of self-preservation.
  2. One or more care recipients that are rendered incapable of self-preservation are located at other than the level of exit discharge serving such a facility.
• CBC § 1105.7 High relevance — show source text

  1105.7 Smoke compartments. Smoke compartments shall be provided in existing Group I-2, Condition 2, in accordance with Sections 1105.7.1 through 1105.7.6.

  1105.7.1 Design. Smoke barriers shall be provided to subdivide each story used for patients sleeping with an occupant load of more than 30 patients into not fewer than two smoke compartments.

  1105.7.1.1 Refuge areas. Refuge areas shall be provided within each smoke compartment. The size of the refuge area shall accommodate the occupants and care recipients from the adjoining smoke compartment. Where a smoke compartment is adjoined by two or more smoke compartments, the minimum area of the refuge area shall accommodate the largest occupant load of the adjoining compartments.

  The size of the refuge area shall provide the following:

  1. Not less than 30 net square feet (2.8 m [2] ) for each care recipient confined to a bed or stretcher.
  2. Not less than 15 square feet (1.4 m [2] ) for each resident in a Group I-2 using mobility assistance devices.
  3. Not less than 6 square feet (0.56 m [2] ) for each occupant not addressed in Items 1 and 2.

  Areas of spaces permitted to be included in the calculation of the refuge area are corridors, sleeping areas, treatment rooms, lounge or dining areas and other low-hazard areas.

  2025 CALIFORNIA FIRE CODE 11-21

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  CONSTRUCTION REQUIREMENTS FOR EXISTING BUILDINGS

  1105.7.2 Smoke barriers. Smoke barriers shall be constructed in accordance with Section 709 of the California Building Code .

  Exceptions:

  1. Existing smoke barriers are permitted to remain where the existing smoke barrier has a minimum fire-resistance rating of [1] / 2 hour.
  2. Smoke barriers shall be permitted to terminate at an atrium enclosure in accordance with Section 404.6 of the Califor- nia Building Code .

  1105.7.3 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.

  Exceptions:

  1. Existing wired glass vision panels in doors shall be permitted to remain.
  2. Existing nonlabeled protection plates shall be permitted to remain.

  1105.7.4 Penetrations. Penetrations of smoke barriers shall comply with the California Building Code .

  Exception: Approved existing materials and methods of construction.

  1105.7.5 Joints. Joints made in or between smoke barriers shall comply with the California Building Code .

  Exception: Approved existing materials and methods of construction.

  1105.7.6 Duct and air transfer openings. Penetrations in a smoke barrier by duct and air transfer openings shall comply with Section 717 of the California Building Code .

  Exception: Where existing duct and air transfer openings in smoke barriers exist without smoke dampers, they shall be permitted to remain. Any changes to existing smoke dampers shall be submitted for review and approved in accordance with Section 717 of the California Building Code .

  1105.8 Group I-2 care suites. Care suites in existing Group I-2, Condition 2 occupancies shall comply with Sections 407.4.4 through 407.4.4.7.2 of the California Building Code .

• CBC § 0.019 High relevance — show source text

  Exceptions:

  1. Smoke dampers are not required where the building is equipped throughout with an approved smoke control system in accordance with Section 909, and smoke dampers are not necessary for the operation and control of the system.
  2. Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness and there are no openings serving the corridor.

  [SFM] For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, a listed smoke damper designed to resist the passage of smoke shall also be provided at each point a duct or air transfer opening penetrates a fire-resistance rated corridor enclosure required to have smoke and draft doors in accordance with Section 716.2.2.1 or doors that provide an effective barrier to limit the transfer of smoke in accordance with Section 407.3.1.

  Exceptions: 1. Smoke dampers are not required where ducts are used as part of an approved mechanical smoke control system designed in accordance with Section 909 and where the smoke damper will interfere with the operation of the smoke control system. 2. Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness and there are no openings serving the corridor. 717.5.5 Smoke barriers. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a smoke barrier. Smoke dampers and smoke damper actuation methods shall comply with Section 717.3.3.2.

  Exception: Smoke dampers are not required where the openings in ducts are limited to a single smoke compartment and the ducts are constructed of steel. � 717.5.6 Exterior walls. Ducts and air transfer openings in fire-resistance-rated exterior walls required to have protected openings in accordance with Section 705.11 shall be protected with listed fire dampers installed in accordance with their listing.

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  FIRE AND SMOKE PROTECTION FEATURES

  717.5.7 Smoke partitions. A listed smoke damper designed to resist the passage of smoke shall be provided at each point that an air transfer opening penetrates a smoke partition. Smoke dampers and smoke damper actuation methods shall comply with Section 717.3.3.2.

  Exception: Where the installation of a smoke damper will interfere with the operation of a required smoke control system in accordance with Section 909, approved alternative protection shall be utilized.

  717.6 Horizontal assemblies. Penetrations by ducts and air transfer openings of a floor, floor/ceiling assembly or the ceiling membrane of a roof/ceiling assembly shall be protected by a shaft enclosure that complies with Section 713 or shall comply with Sections 717.6.1 through 717.6.3.

• CBC § 7-21 High relevance — show source text

  713 Shaft Enclosures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-21

  714 Penetrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-23

  715 Joints and Voids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-26

  716 Opening Protectives . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-27

  717 Ducts and Air Transfer Openings . . . . . . . . . . . . . . . . 7-34

  718 Concealed Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-40

  719 Fire-Resistance Requirements for Plaster . . . . . . . . 7-42

  720 Thermal- and Sound-Insulating Materials . . . . . . . . 7-42

  721 Prescriptive Fire Resistance. . . . . . . . . . . . . . . . . . . . . 7-43

  722 Calculated Fire Resistance. . . . . . . . . . . . . . . . . . . . . . 7-66

  CHAPTER 7A [SFM] MATERIALS AND CONSTRUCTION

  METHODS FOR EXTERIOR WILDFIRE EXPOSURE . . . . . . . 7A-1

  CHAPTER 8 INTERIOR FINISHES. . . . . . . . . . . . . . . . . . . . . .8-1

  801 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3

  802 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3

  803 Wall and Ceiling Finishes . . . . . . . . . . . . . . . . . . . . . . . . 8-3

  804 Interior Floor Finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6

  805 Combustible Materials in Types I and II Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7

  806 Decorative Materials and Trim . . . . . . . . . . . . . . . . . . . 8-7

  807 Insulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8

  808 Acoustical Ceiling Systems . . . . . . . . . . . . . . . . . . . . . . 8-8

  CHAPTER 9 FIRE PROTECTION AND LIFE

• CBC § 712.1.5.2 High relevance — show source text

  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

  3. 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

  712.1.8 Masonry chimney. Approved vertical openings for masonry chimneys shall be permitted where the annular space is fireblocked at each floor level in accordance with Section 718.2.5.

  712.1.9 Two-story openings. In other than Groups I-2 and I-3, a vertical opening that is not used as one of the applications specified in this section shall be permitted if the opening complies with all of the following items:

  1. Does not connect more than two stories.

  2. Does not penetrate a horizontal assembly that separates fire areas or smoke barriers that separate smoke compartments.

  3. Is not concealed within the construction of a wall or a floor/ceiling assembly.

  4. Is not open to a corridor in Group I and R occupancies.

  5. Is not open to a corridor on nonsprinklered floors.

  6. Is separated from floor openings and air transfer openings serving other floors by construction conforming to required shaft enclosures.

  712.1.10 Parking garages. Vertical openings in parking garages for automobile ramps, elevators and duct systems shall comply with Section 712.1.10.1, 712.1.10.2 or 712.1.10.3, as applicable.

  712.1.10.1 Automobile ramps. Vertical openings for automobile ramps in parking garages shall be permitted where constructed in accordance with Sections 406.5 and 406.6.

  712.1.10.2 Elevators. Vertical openings for elevator hoistways in parking garages that serve only the parking garage, and complying with Sections 406.5 and 406.6, respectively, shall be permitted.

  712.1.10.3 Duct systems. Vertical openings for mechanical exhaust or supply duct systems in parking garages complying with Sections 406.5 and 406.6, respectively, shall be permitted to be unenclosed where such duct system is contained within and serves only the parking garage.

• CBC § 705.10 High relevance — show source text

  705.10 Joints. Joints made in or between exterior walls required by this section to have a fire-resistance rating shall comply with Section 715.

  Exception: Joints in exterior walls that are permitted to have unprotected openings.

  705.10.1 Voids. The void created at the intersection of a floor/ceiling assembly and an exterior curtain wall assembly shall be protected in accordance with Section 715.4.

  705.11 Ducts and air transfer openings. Penetrations by air ducts and air transfer openings in fire-resistance-rated exterior walls required to have protected openings shall comply with Section 717.

  Exception: Foundation vents installed in accordance with this code are permitted.

  705.12 Parapets. Parapets shall be provided on exterior walls of buildings.

  Exceptions: A parapet need not be provided on an exterior wall where any of the following conditions exist:

  1. The wall is not required to be fire-resistance rated in accordance with Table 705.5 because of fire separation distance.
  2. The building has an area of not more than 1,000 square feet (93 m [2] ) on any floor.
  3. Walls that terminate at roofs of not less than 2-hour fire-resistance-rated construction or where the roof, including the deck or slab and supporting construction, is constructed entirely of noncombustible materials.
  4. One-hour fire-resistance-rated exterior walls that terminate at the underside of the roof sheathing, deck or slab, provided that: 4.1. Where the roof/ceiling framing elements are parallel to the walls, such framing and elements supporting such framing shall not be of less than 1-hour fire-resistance-rated construction for a width of 4 feet (1220 mm) for Groups R and U and 10 feet (3048 mm) for other occupancies, measured from the interior side of the wall. 4.2. Where roof/ceiling framing elements are not parallel to the wall, the entire span of such framing and elements supporting such framing shall not be of less than 1-hour fire-resistance-rated construction. 4.3. Openings in the roof shall not be located within 5 feet (1524 mm) of the 1-hour fire-resistance-rated exterior wall for Groups R and U and 10 feet (3048 mm) for other occupancies, measured from the interior side of the wall. 4.4. The entire building shall be provided with not less than a Class B roof covering.
  5. In Groups R-2 and R-3 where the entire building is provided with a Class C roof covering, the exterior wall shall be permitted to terminate at the underside of the roof sheathing or deck in Types III, IV and V construction, provided that one or both of the following criteria is met: 5.1. The roof sheathing or deck is constructed of approved noncombustible materials or of fire-retardant-treated wood for a distance of 4 feet (1220 mm). 5.2. The roof is protected with 0.625-inch (16 mm) Type X gypsum board directly beneath the underside of the roof sheathing or deck, supported by not less than nominal 2-inch (51 mm) ledgers attached to the sides of the roof framing members for a minimum distance of 4 feet (1220 mm).
  6. Where the wall is permitted to have not less than 25 percent of the exterior wall areas containing unprotected openings based on fire separation distance as determined in accordance with Section 705.9.