What limits apply to chimney offsets, insulation shields and elbow counts for factory-built chimneys?

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

• CRC § 0.52 High relevance — show source text

  R1004.5 Gasketed fireplace doors. A gasketed fireplace door shall not be installed on a factory-built fireplace except where the fireplace system has been specifically tested, listed and labeled for such use in accordance with UL 127.

  SECTION R1005—FACTORY-BUILT CHIMNEYS

  R1005.1 Listing. Factory-built chimneys shall be listed and labeled and shall be installed and terminated in accordance with the manufacturer’s installation instructions.

  R1005.2 Decorative shrouds. Decorative shrouds shall not be installed at the termination of factory-built chimneys except where the shrouds are listed and labeled for use with the specific factory-built chimney system and installed in accordance with the manufacturer’s installation instructions.

  R1005.3 Solid-fuel appliances. Factory-built chimneys installed in dwelling units with solid-fuel-burning appliances shall comply with the Type HT requirements of UL 103 and shall be marked “Type HT” and “Residential Type and Building Heating Appliance Chimney.”

  Exception: Chimneys for use with open combustion chamber fireplaces shall comply with the requirements of UL 103 and shall be marked “Residential Type and Building Heating Appliance Chimney.”

  Chimneys for use with open combustion chamber appliances installed in buildings other than dwelling units shall comply with the requirements of UL 103 and shall be marked “Building Heating Appliance Chimney” or “Residential Type and Building Heating Appliance Chimney.”

  R1005.4 Factory-built fireplaces. Chimneys for use with factory-built fireplaces shall comply with the requirements of UL 127.

  R1005.5 Support. Where factory-built chimneys are supported by structural members, such as joists and rafters, those members shall be designed to support the additional load.

  R1005.6 Medium-heat appliances. Factory-built chimneys for medium-heat appliances producing flue gases having a temperature above 1,000°F (538°C), measured at the entrance to the chimney, shall comply with UL 959.

  R1005.7 Factory-built chimney offsets. Where a factory-built chimney assembly incorporates offsets, no part of the chimney shall be at an angle of more than 30 degrees (0.52 rad) from vertical at any point in the assembly and the chimney assembly shall not include more than four elbows.

  R1005.8 Insulation shield. Where factory-built chimneys pass through insulated assemblies, an insulation shield constructed of steel having a thickness of not less than 0.0187 inch (0.4712 mm) (No. 26 gage) shall be installed to provide clearance between the chimney and the insulation material. The clearance shall be not less than the clearance to combustibles specified by the chimney manufacturer’s installation instructions. Where chimneys pass through attic space, the shield shall terminate not less than 2 inches (51 mm) above the insulation materials and shall be secured in place to prevent displacement. Insulation shields provided as part of a listed chimney system shall be installed in accordance with the manufacturer’s installation instructions.

  R1005.9 Factory-built chimney offsets. Where a fireplace manufacturer’s instructions do not address factory-built chimney offsets, no part of the chimney shall be at an angle of more than 30 degrees (0.52 rad) from vertical at any point in the assembly and the chimney assembly shall not include more than four elbows.

  SECTION R1006—EXTERIOR AIR SUPPLY

• CRC § 0.52 High relevance — show source text

  R1005.6 Medium-heat appliances. Factory-built chimneys for medium-heat appliances producing flue gases having a temperature above 1,000°F (538°C), measured at the entrance to the chimney, shall comply with UL 959.

  R1005.7 Factory-built chimney offsets. Where a factory-built chimney assembly incorporates offsets, no part of the chimney shall be at an angle of more than 30 degrees (0.52 rad) from vertical at any point in the assembly and the chimney assembly shall not include more than four elbows.

  R1005.8 Insulation shield. Where factory-built chimneys pass through insulated assemblies, an insulation shield constructed of steel having a thickness of not less than 0.0187 inch (0.4712 mm) (No. 26 gage) shall be installed to provide clearance between the chimney and the insulation material. The clearance shall be not less than the clearance to combustibles specified by the chimney manufacturer’s installation instructions. Where chimneys pass through attic space, the shield shall terminate not less than 2 inches (51 mm) above the insulation materials and shall be secured in place to prevent displacement. Insulation shields provided as part of a listed chimney system shall be installed in accordance with the manufacturer’s installation instructions.

  R1005.9 Factory-built chimney offsets. Where a fireplace manufacturer’s instructions do not address factory-built chimney offsets, no part of the chimney shall be at an angle of more than 30 degrees (0.52 rad) from vertical at any point in the assembly and the chimney assembly shall not include more than four elbows.

  SECTION R1006—EXTERIOR AIR SUPPLY

  R1006.1 Exterior air. Factory-built or masonry fireplaces covered in this chapter shall be equipped with an exterior air supply to ensure proper fuel combustion unless the room is mechanically ventilated and controlled so that the indoor pressure is neutral or positive.

  R1006.1.1 Factory-built fireplaces. Exterior combustion air ducts for factory-built fireplaces shall be a listed component of the fireplace and shall be installed in accordance with the fireplace manufacturer’s instructions.

  R1006.1.2 Masonry fireplaces. Listed combustion air ducts for masonry fireplaces shall be installed in accordance with the terms of their listing and the manufacturer’s instructions.

  R1006.2 Exterior air intake. The exterior air intake shall be capable of supplying all combustion air from the exterior of the dwelling unit or from spaces within the dwelling unit ventilated with outdoor air such as nonmechanically ventilated crawl or attic spaces. The

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  CHIMNEYS AND FIREPLACES

  exterior air intake shall not be located within the garage or basement of the dwelling unit. The exterior air intake, for other than listed factory-built fireplaces, shall not be located at an elevation higher than the firebox. The exterior air intake shall be covered with a corrosion-resistant screen of [1] / 4 -inch (6.4 mm) mesh.

• CRC § 5.2 High relevance — show source text

  Defined R202 Dwelling-garage wall and ceiling penetration R302.5.2 System, definition R202 Dwelling Unit Separation R302.2, R302.3 Sprinklers (see Automatic Sprinkler System)

  Electric Vehicle Charging Stations R317.6 Elevator R323.1, R323.3 Emergency Escape and Rescue Openings R319

  Additions R319.6

  Area wells R319.4 Bars, grilles, covers and screens R319.4.4

  Basements, existing R319.7 Dimensions R319.2

  Doors R319.3

  Replacement window R319.5 Under decks and porches R319.2.4 Where required R319.1 Window fall protection R321.2 Emergency Housing Appendix CJ Energy Storage Systems R328 ESS vehicle impact protection Figure R330.8.1 Maximum aggregate ratings of ESS Table R330.5 Protection from impact R330.8 Toxic and highly toxic gas R330.12 Entry 1.8.5, R104.4 Existing Buildings Appendix BO Administrative R101.2, R102.6, R105.1, R105.8, R106.2, R113.1, R113.2 Basements R313.1.2, R319.7 Carbon monoxide alarms R311.2.2, R311.5, R311.6 Flood R104.3.1

  Smoke alarms R310.2.2, R310.6 Stairways R318.7.9 Windows, replacement R319.5 Exterior Balconies and elevated walking surfaces R106.1.6

  Covering R703 Insulation finish systems R703.9 Lath R703.7.1

  Plaster R703.7 Exterior Insulation and Finish Systems (EIFS) 703.9

  Exterior Wall

  Construction R302.1

  Fire-resistance rating R302.1

  Factory Built Chimneys R1005 Fireplace stoves R1005.3 Fireplaces R1004 Fastening Table R602.3(1) Fees, Permit R108 Finishes Flame spread and smoke density R302.9 For ceilings R805 Interior R302.9, R311, R702 Fire Sprinkler System (see Automatic Sprinkler System) Ceiling configurations R309.3.4.1.1, R309.3.4.1.2, R309.3.4.1.3 Flow rate R309.3.4.1 Fireblocking Barrier between stories R302.11,

  R602.8 Chimney R1003.19 Fireplace R1001.12 Fireplaces Chapter 10 Clearance R1001.11 Corbeling R1001.8 Factory-built R1004 Fireblocking R1001.12 Walls R1001.5

  Fire-Resistant Construction R302 Draftstopping R302.2 Dwelling-garage fire separation R302.6 Dwelling-garage opening and penetration R302.5 Exterior walls R302.1 Fireblocking R302.11 Floors R302.13

  Foam plastics R302.8 Insulation R302.10, R302.14 Penetrations R302.4

• CRC § 7.1 High relevance — show source text

  Covering R703 Insulation finish systems R703.9 Lath R703.7.1

  Plaster R703.7 Exterior Insulation and Finish Systems (EIFS) 703.9

  Exterior Wall

  Construction R302.1

  Fire-resistance rating R302.1

  Factory Built Chimneys R1005 Fireplace stoves R1005.3 Fireplaces R1004 Fastening Table R602.3(1) Fees, Permit R108 Finishes Flame spread and smoke density R302.9 For ceilings R805 Interior R302.9, R311, R702 Fire Sprinkler System (see Automatic Sprinkler System) Ceiling configurations R309.3.4.1.1, R309.3.4.1.2, R309.3.4.1.3 Flow rate R309.3.4.1 Fireblocking Barrier between stories R302.11,

  R602.8 Chimney R1003.19 Fireplace R1001.12 Fireplaces Chapter 10 Clearance R1001.11 Corbeling R1001.8 Factory-built R1004 Fireblocking R1001.12 Walls R1001.5

  Fire-Resistant Construction R302 Draftstopping R302.2 Dwelling-garage fire separation R302.6 Dwelling-garage opening and penetration R302.5 Exterior walls R302.1 Fireblocking R302.11 Floors R302.13

  Foam plastics R302.8 Insulation R302.10, R302.14 Penetrations R302.4

  Townhouse separation R302.2 Two-family dwellings R302.3 Under-stair protection R302.7 Wall and ceiling finishes R302.9 Fire-Separation Distance Exterior walls and wall projections R302.1 Ground-mounted photovoltaic systems R329.7, R329.8 Fixtures

  Clearance R327.1

  Flood protection R306.1.6 Plumbing fixture, general R326, R327 Flame Spread Index R302.10, R302.9 Flashing R703.4, R703.8.5, R903.2, R905 Flood Protection Plan Areas protected by the facilities of Central Valley Appendix CK Flood-Resistant Construction

  General and structural R301.2.4, R306 Floors

  Bathtub and shower R327.2 Concrete (on ground) R506 Loads R301, R501.2 Steel framing R505 Treated wood (on ground) R504

  Wood framing R502 Flue

  Area R1003.14, R1003.15 Lining R1003.11, R1003.12 Multiple R1003.13 Foam Plastics R303 Footings R403 Foundations Chapter 4 Cripple walls R602.10.9, R602.11.2, R602.9

  Frost protection R403.1.4.1 Inspection R109.1.1 Walls R404

  Frame

• CRC § 104.1 High relevance — show source text

  [A] 104.1 General. The building official is hereby authorized and directed to enforce the provisions of this code.

  [A] 104.2 Determination of compliance. The building official shall have the authority to determine compliance with this code, to render interpretations of this code and to adopt policies and procedures in order to clarify the application of its provisions. Such interpretations, policies and procedures:

  1. Shall be in compliance with the intent and purpose of this code.
  2. Shall not have the effect of waiving requirements specifically provided for in this code.

  [A] 104.2.1 Listed compliance. Where this code or a referenced standard requires equipment, materials, products or services to be listed and a listing standard is specified, the listing shall be based on the specified standard. Where a listing standard is not specified, the listing shall be based on an approved listing criteria. Listings shall be germane to the provision requiring the listing. Installation shall be in accordance with the listing and the manufacturer’s instructions, and where required to verify compliance, the listing standard and manufacturer’s instructions shall be made available to the building official.

  [A] 104.2.2 Technical assistance. To determine compliance with this code, the building official is authorized to determine compliance with this code, to require the owner or owner’s authorized agent to provide a technical opinion and report.

  [A] 104.2.2.1 Cost. A technical opinion and report shall be provided without charge to the jurisdiction.

  [A] 104.2.2.2 Preparer qualifications. The technical opinion and report shall be prepared by a qualified engineer, specialist, laboratory or specialty organization acceptable to the building official. The building official is authorized to require design submittals to be prepared by, and bear the stamp of, a registered design professional.

  [A] 104.2.2.3 Content. The technical opinion and report shall analyze the properties of the design, operation or use of the building or premises and the facilities and appurtenances situated thereon to identify and propose necessary recommendations.

  [A] 104.2.2.4 Tests. Where there is insufficient evidence of compliance with the provisions of this code, the building official shall have the authority to require tests as evidence of compliance. Test methods shall be as specified in this code or by other recognized test standards. In the absence of recognized test standards, the building official shall approve the testing procedures. Such tests shall be performed by a party acceptable to the building official.

  [A] 104.2.3 Alternative materials, design and methods of construction and equipment. The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved.

  Exception: Performance-based alternative materials, designs or methods of construction and equipment complying with the International Code Council Performance Code . This exception shall not apply to alternative structural materials or to alternative structural designs. [DSA-SS, DSA-SS/CC] The International Code Council Performance Code is not permitted by DSA.

  [DSA-SS, DSA-SS/CC & OSHPD 1, 1R, 2, 4 & 5] Alternative system shall satisfy ASCE 7 Section 1.3, unless more restrictive require- ments are established by this code for an equivalent system.

  [DSA-SS, DSA-SS/CC] Alternative systems shall also satisfy the California Administrative Code, Section 4-304.

• CRC § 5.5 Medium relevance — show source text

  The width used to calculate_A_ and_I_ shall not exceed 8 inches.
  e. Vertical core is assumed to be circular. Another shape of core is permitted provided the minimum thickness is 7 inches, the moment of inertia,I, about the centerline of the
  wall (ignoring the web) is not less than 200 inch4, and the area,A, is not less than 49 square inches. The width used to calculate_A_ and_I_ shall not exceed 8 inches.
  f. Vertical core is assumed to be circular. Another shape of core is permitted provided the minimum thickness is 5.5 inches, the moment of inertia,I, about the centerline of the
  wall is not less than 76 inch4, and the area,A, is not less than 30.25 square inches. The width used to calculate_A_ and_I_ shall not exceed 6.25 inches.|For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa, 1 pound per cubic foot = 2402.77 kg/m3, 1 square inch = 645.16 mm2, 1 inch4 = 42 cm4.
  NA = Not Applicable.
  a. Width “W,” thickness “T,” spacing and web thickness, refer to Figures R608.3(2) and R608.3(3).
  b. Wall weight is based on a unit weight of concrete of 150 pcf. For flat walls the weight is based on the nominal thickness. The tabulated values do not include any allowance for
  interior and exterior finishes.
  c. Nominal wall thickness. The actual as-built thickness of a flat wall shall not be more than1/2 inch less or more than1/4 inch more than the nominal dimension indicated.
  d. Vertical core is assumed to be elliptical-shaped. Another shape of core is permitted provided the minimum thickness is 5 inches, the moment of inertia,I, about the centerline
  of the wall (ignoring the web) is not less than 65 inch4, and the area,A, is not less than 31.25 square inches. The width used to calculate_A_ and_I_ shall not exceed 8 inches.
  e. Vertical core is assumed to be circular. Another shape of core is permitted provided the minimum thickness is 7 inches, the moment of inertia,I, about the centerline of the
  wall (ignoring the web) is not less than 200 inch4, and the area,A, is not less than 49 square inches. The width used to calculate_A_ and_I_ shall not exceed 8 inches.
  f. Vertical core is assumed to be circular. Another shape of core is permitted provided the minimum thickness is 5.5 inches, the moment of inertia,I, about the centerline of the
  wall is not less than 76 inch4, and the area,A, is not less than 30.25 square inches. The width used to calculate_A_ and_I_ shall not exceed 6.25 inches.|

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  WALL CONSTRUCTION

  FIGURE R608.3(1)—FLAT WALL SYSTEM

  CONCRETE WALL THICKNESS

  FORM STAY-IN-PLACE OR REMOVABLE

  CONCRETE

  VERTICAL WALL REINFORCEMENT AS REQUIRED

  PLAN VIEW

• CRC § 104.5 Medium relevance — show source text

  [A] 104.5 Identification. The fire code official shall carry proper identification when inspecting structures or premises in the performance of duties under this code.

  [A] 104.6 Notices and orders. The fire code official shall issue necessary notices or orders to ensure compliance with this code. Notices of violations shall be in accordance with Section 113.

  [A] 104.7 Official records. The fire code official shall keep official records as required by Sections 104.7.1 through 104.7.6. Such official records shall be retained for not less than 5 years or for as long as the building or structure to which such records relate remains in existence, unless otherwise provided by other regulations.

  [A] 104.7.1 Approvals. A record of approvals shall be maintained by the fire code official and shall be available for public inspection during business hours in accordance with applicable laws.

  [A] 104.7.2 Inspections. The fire code official shall keep a record of each inspection made, including notices and orders issued, showing the findings and disposition of each.

  104.7.3 Fire records. The fire code official shall keep a record of fires occurring within its jurisdiction and of facts concerning the same, including statistics as to the extent of such fires and the damage caused thereby, together with other information as required by the fire code official.

  [A] 104.7.4 Code alternatives and modifications. Application for alternative materials, design and methods of construction and equipment in accordance with Section 104.2.3; modifications in accordance with Section 104.2.4; and documentation of the final decision of the fire code official for either shall be in writing and shall be retained in the official records.

  [A] 104.7.5 Tests. The fire code official shall keep a record of tests conducted to comply with Sections 104.2.2.4 and 104.2.3.5.

  [A] 104.7.6 Fees. The fire code official shall keep a record of fees collected and refunded in accordance with Section 108.

  [A] 104.8 Liability. The fire code official, member of the board of appeals, officer or employee charged with the enforcement of this code, while acting for the jurisdiction, in good faith and without malice in the discharge of the duties required by this code or other pertinent law or ordinance, shall not thereby be rendered personally liable, either civilly or criminally, and is hereby relieved from all personal liability for any damage accruing to persons or property as a result of any act or by reason of an act or omission in the discharge of official duties.

  [A] 104.8.1 Legal defense. Any suit or criminal complaint instituted against any officer or employee because of an act performed by that officer or employee in the lawful discharge of duties and under the provisions of this code or other laws or ordinances implemented through the enforcement of this code shall be defended by the legal representatives of the jurisdiction until the final termination of the proceedings. The fire code official or any subordinate shall not be liable for costs in an action, suit or proceeding that is instituted in pursuance of the provisions of this code; and any officer of the department of fire prevention, acting in

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  DIVISION II—SCOPE AND ADMINISTRATION

• CRC § 803.1.2 Medium relevance — show source text

  803.1.2 Elbows. Single-appliance venting configurations with zero (0) lateral lengths in Table 803.1.2(1), Table 803.1.2(2), and Table 803.1.2(5) shall not have elbows in the venting system. Single-appliance venting with lateral lengths include two 90 degree elbows. For each additional elbow up to and including 45 degrees, the maximum capacity listed in the venting tables shall be reduced by 5 percent. For each additional elbow greater than 45 degrees up to and including 90 degrees, the maximum capacity listed in the venting tables shall be reduced by 10 percent. Where multiple offsets occur in a vent, the total lateral length of all offsets combined shall not exceed that specified in Table 803.1.2(1) through Table 803.1.2(5). [NFPA 54:13.1.3]

  803.1.3 Zero Lateral. Zero (0) lateral ( L ) shall apply only to a straight vertical vent attached to a top outlet draft hood or flue collar. [NFPA 54:13.1.4]

  803.1.4 High-Altitude Installations. Sea level input ratings shall be used when determining maximum capacity for high-altitude installation. Actual input (derated for altitude) shall be used for determining minimum capacity for high-altitude installation. [NFPA 54:13.1.5]

  803.1.5 Two-Stage/Modulating Appliances. For appliances with more than one input rate, the minimum vent capacity (FAN Min) determined from Table 803.1.2(1) through Table 803.2(9) shall be less than the lowest appliance input rating, and the maximum vent capacity (FAN Max/NAT Max) determined from the tables shall be greater than the highest appliance rating input. [NFPA 54:13.1.6]

  803.1.6 Corrugated Chimney Liners. Listed corrugated metallic chimney liner systems in masonry chimneys shall be sized by using Table 803.1.2(1) or Table 803.1.2(2) for Type B vents, with the maximum capacity reduced by 20 percent (0.80 x maximum capacity) and the minimum capacity as shown in Table 803.1.2(1) or Table 803.1.2(2).

  Corrugated metallic liner systems installed with bends or offsets shall have their maximum capacity fur

  ther reduced in accordance with Section 803.1.2. The 20 percent reduction for corrugated metallic chimney liner systems includes an allowance for one long radius 90 degree (1.57 rad) turn at the bottom of the liner. [NFPA 54:13.1.7]

  803.1.7 Connection to Chimney Liners. Connections between chimney liners and listed double-wall connectors shall be made with listed adapters designed for such purpose. [NFPA 54:13.1.8]

• CRC § 103.1 Medium relevance — show source text

  PART 2—ADMINISTRATION AND ENFORCEMENT

  SECTION 103—CODE COMPLIANCE AGENCY

  [A] 103.1 Creation of agency. The [ INSERT NAME OF DEPARTMENT ] is hereby created and the official in charge thereof shall be known as the fire code official. The function of the agency shall be the implementation, administration and enforcement of the provisions of this code.

  [A] 103.2 Appointment. The fire code official shall be appointed by the chief appointing authority of the jurisdiction.

  [A] 103.3 Deputies. In accordance with the prescribed procedures of this jurisdiction and with the concurrence of the appointing authority, the fire code official shall have the authority to appoint a deputy fire code official, other related technical officers, inspectors and other employees. Such employees shall have powers as delegated by the fire code official.

  SECTION 104—DUTIES AND POWERS OF THE FIRE CODE OFFICIAL

  [A] 104.1 General. The fire code official is hereby authorized to enforce the provisions of this code.

  [A] 104.2 Determination of compliance. The fire code official shall have the authority to determine compliance with this code, to render interpretations of this code and to adopt policies and procedures in order to clarify the application of its provisions. Such interpretations, policies and procedures:

  1. Shall be in compliance with the intent and purpose of this code.
  2. Shall not have the effect of waiving requirements specifically provided for in this code.

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  DIVISION II—SCOPE AND ADMINISTRATION

  [A] 104.2.1 Listed compliance. Where this code or a referenced standard requires equipment, materials, products or services to be listed and a listing standard is specified, the listing shall be based on the specified standard. Where a listing standard is not specified, the listing shall be based on an approved listing criteria. Listings shall be germane to the provision requiring the listing. Installation shall be in accordance with the listing and the manufacturer’s instructions, and where required to verify compliance, the listing standard and manufacturer’s instructions shall be made available to the fire code official.

  [A] 104.2.2 Technical assistance. To determine compliance with this code, the fire code official is authorized to require the owner or owner’s authorized agent to provide a technical opinion and report.

  [A] 104.2.2.1 Cost. A technical opinion and report shall be provided without charge to the jurisdiction.

  [A] 104.2.2.2 Preparer qualifications. The technical opinion and report shall be prepared by a qualified engineer, specialist, laboratory or fire safety specialty organization acceptable to the fire code official. The fire code official is authorized to require design submittals to be prepared by, and bear the stamp of, a registered design professional.

  [A] 104.2.2.3 Content. The technical opinion and report shall analyze the properties of the design, operation or use of the building or premises and the facilities and appurtenances situated thereon to identify and propose necessary recommendations.

• CRC § 910.3 Medium relevance — show source text

  910.3 Smoke and heat vents. The design and installation of smoke and heat vents shall be in accordance with Sections 910.3.1 through 910.3.3.

  910.3.1 Listing and labeling. Smoke and heat vents shall be listed and labeled to indicate compliance with UL 793 or FM 4430 or ICC-ES AC 331.

  910.3.2 Smoke and heat vent locations. Smoke and heat vents shall be located 20 feet (6096 mm) or more from adjacent lot lines and fire walls and 10 feet (3048 mm) or more from fire barriers. Vents shall be uniformly located within the roof in the areas of the building where the vents are required to be installed by Section 910.2, with consideration given to roof pitch, sprinkler location and structural members.

  910.3.3 Smoke and heat vents area. The required aggregate area of smoke and heat vents shall be calculated as follows:

  For buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1:

  Equation 9-3 A VR = V /9000

  where:

  A VR = The required aggregate vent area (ft [2] ). V = Volume (ft [3] ) of the area that requires smoke removal.

  For unsprinklered buildings:

  Equation 9-4 A VR = A FA /50

  where:

  A VR = The required aggregate vent area (ft [2] ).

  A FA = The area of the floor in the area that requires smoke removal.

  910.3.4 Vent operation. Smoke and heat vents shall be capable of being operated by approved automatic and manual means.

  910.3.5 Fusible link temperature rating. Where vents are installed in areas provided with automatic fire sprinklers and the vents operate by fusible link, the fusible link shall have a temperature rating of 360°F (182°C).

  910.4 Mechanical smoke removal systems. Mechanical smoke removal systems shall be designed and installed in accordance with Sections 910.4.1 through 910.4.7.

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  FIRE PROTECTION AND LIFE SAFETY SYSTEMS

  910.4.1 Automatic sprinklers required. The building shall be equipped throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1.

  910.4.2 Exhaust fan construction. Exhaust fans that are part of a mechanical smoke removal system shall be rated for operation at 221°F (105°C). Exhaust fan motors shall be located outside of the exhaust fan airstream.

  910.4.3 System design criteria. The mechanical smoke removal system shall be sized to exhaust the building at a minimum rate of two air changes per hour based on the volume of the building or portion thereof without contents. The capacity of each exhaust fan shall not exceed 30,000 cubic feet per minute (14.2 m [3] /s).

• CRC § 1001.11 Medium relevance — show source text

  3||||X|||||||||||||||||||| |R1001.4||||X|||||||||||||||||||| |Table R1001.1, Footnote (b)||||X|||||||||||||||||||| |R1001.11|||X||||||||||||||||||||| |Figure 1001.11|||X||||||||||||||||||||| |R1001.12|||X||||||||||||||||||||| |R1003.3||||X|||||||||||||||||||| |R1003.4||||X|||||||||||||||||||| |R1003.9.1|||X||||||||||||||||||||| |R1003.9.2|||X||||||||||||||||||||| |R1003.11.3||||X|||||||||||||||||||| |R1003.14||||X|||||||||||||||||||| |R1003.18|||X||||||||||||||||||||| |Figure R1003.18|||X||||||||||||||||||||| |R1003.19|||X||||||||||||||||||||| |R1004.1.1||||X|||||||||||||||||||| |R1004.4||||†||||||||||||||||||||

  The state agency does not adopt sections identified with the following symbol: †

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  10 CHIMNEYS AND FIREPLACES

  User notes:

  About this chapter: Chapter 10 contains requirements for the construction, seismic reinforcing and anchorage of masonry chimneys and fireplaces; and establishes standards for the use and installation of factory-built chimneys, fireplaces and masonry heaters. Chimneys and fireplaces constructed of masonry rely on prescriptive requirements for the details of their construction; factory-built versions rely on the listing and labeling method of approval.

  SECTION R1001—MASONRY FIREPLACES

  R1001.1 General. Masonry fireplaces shall be constructed in accordance with this section and the applicable provisions of Chapters 3 and 4.

  TABLE R1001.1—SUMMARY OF REQUIREMENTS FOR MASONRY FIREPLACES AND CHIMNEYS	Col2	Col3
  ** ITEM**	** LETTERa**	** REQUIREMENTS**
  Hearth slab thickness	A	4 inches
  Hearth extension (each side of opening)	B	8-inch fireplace opening < 6 square feet. 12-inch fireplace opening ≥ 6 square feet.
  Hearth extension (front of opening)	C	16-inch fireplace opening < 6 square feet. 20-inch fireplace opening ≥ 6 square feet.
  Hearth slab reinforcing	D	Reinforced to carry its own weight and all imposed loads.
  Thickness of wall of firebox	E	10-inch solid brick or 8 inches where a firebrick lining is used. Joints in firebrick1/4-inch maximum.
  Distance from top of opening to throat	F	8 inches
  Smoke chamber wall thickness Unlined walls	G	6 inches 8 inches
  Chimney Vertical reinforcingb	H	Four No. 4 full-length bars for chimney up to 40 inches wide. Add two No. 4 bars for each additional 40 inches or fraction of width or each additional flue.

• CRC § 10.6.2 Medium relevance — show source text

  10.6.2|See Section
  R602.10.6.2| |Intermittent
  Bracing
  Methods
  (continued)|PFG
  Portal frame at
  garage|7/16″||See Section R602.10.6.3|See Section
  R602.10.6.3| |Continuous
  Sheathing
  Methods|CS-WSP
  Continuously
  sheathed wood
  structural panel|3/8″||Exterior sheathing
  per Table R602.3(3)|6″ edges 12″ field| |Continuous
  Sheathing
  Methods|CS-WSP
  Continuously
  sheathed wood
  structural panel|3/8″||Interior sheathing per
  Table R602.3(1) or R602.3(2)|Varies by fastener| |Continuous
  Sheathing
  Methods|CS-Gb, c
  Continuously
  sheathed wood
  structural panel
  adjacent to
  garage openings|3/8″||See Method CS-WSP|See Method CS-WSP| |Continuous
  Sheathing
  Methods|CS-PF
  Continuously
  sheathed
  portal frame|7/16″||See Section R602.10.6.4|See Section
  R602.10.6.4|

  2025 CALIFORNIA RESIDENTIAL CODE 6-35

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  WALL CONSTRUCTION

  TABLE R602.10.4—BRACING METHODS—continued	Col2	Col3	Col4	Col5	Col6
  ** METHODS, MATERIAL**	** METHODS, MATERIAL**	** MINIMUM THICKNESS**	** FIGURE**	** CONNECTION CRITERIAa**	** CONNECTION CRITERIAa**
  ** METHODS, MATERIAL**	** METHODS, MATERIAL**	** MINIMUM THICKNESS**	** FIGURE**	** Fasteners**	** Spacing**
  Continuous Sheathing Methods (continued)	CS-SFBd Continuously sheathed structural fiberboard	1/2″ or25/32″ for maximum 16″ stud spacing		11/2″ long × 0.12″ dia. (for1/2″ thick sheathing) 13/4″ long × 0.12″ dia. (for25/32″ thick sheathing) galvanized roofing nails	3″ edges 6″ field
  For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 degree = 0.0175 rad, 1 pound per square foot = 47.8 N/m2, 1 mile per hour = 0.447 m/s. a. Adhesive attachment of wall sheathing, including Method GB, shall not be permitted in Seismic Design Categories C, D0, D1 and D2. b. Applies to panels next to garage door opening where supporting gable end wall or roof load only. Shall only be used on one wall of the garage. In Seismic Design Categories D0, D1 and D2, roof covering dead load shall not exceed 3 psf. c.