Appliance Venting & Chimneys

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

• CRC § 803.0. High relevance — show source text

  (1) Those listed in Section 803.0.

  (2) The effective areas of the vent connector and chimney flue of a venting system serving a single appliance with a draft hood shall be not less than the area

  of the appliance flue collar or draft hood outlet or greater than seven times the draft hood outlet area.

  (3) The effective area of the chimney flue of a venting system serving two appliances with draft hoods shall be not less than the area of the larger draft hood outlet plus 50 percent of the area of the smaller draft hood outlet or greater than seven times the smaller draft hood outlet area.

  (4) Chimney venting systems using mechanical draft shall be sized in accordance with engineering methods.

  (5) Other engineering methods. [NFPA 54:12.6.3.1]

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  CHIMNEYS AND VENTS

  FIGURE 802.5.4

  TYPICAL TERMINATION LOCATIONS FOR

  CHIMNEYS AND SINGLE-WALL METAL PIPES SERVING

  RESIDENTIAL-TYPE AND LOW-HEAT APPLIANCE

  [NFPA 54: FIGURE A.12.6.2.1]

  802.5.6 Inspection of Chimneys or Vents. This inspection shall be made after chimneys, vents, or parts thereof, authorized by the permit, have been installed and before such vent or part thereof has been covered or concealed.

  802.5.7 Inspection of Chimneys. Before replacing an existing appliance or connecting a vent connector to a chimney, the chimney passageway shall be examined to ascertain that it is clear and free of obstructions and shall be cleaned if previously used for venting solid- or liquid-fuel-burning appliances or fireplaces. [NFPA 54:12.6.4.1] 802.5.7.1 Standard. Chimneys shall be lined in accordance with NFPA 211. [NFPA 54:12.6.4.2]

  802.5.7.2 Cleanouts. Cleanouts shall be examined and where they do not remain tightly closed when not in use, they shall be repaired or replaced. [NFPA 54:12.6.4.3] 802.5.7.3 Existing Chimney. When inspection reveals that an existing chimney is not safe for the intended application, it shall be repaired, rebuilt, lined, relined, or replaced with a vent or chimney to conform to NFPA 211 and shall be suitable for the appliances to be attached. [NFPA 54:12.6.4.4] 802.5.8 Chimney Serving Appliances Burning Other Fuels. An appliance shall not be connected to a chimney flue serving a separate appliance designed to burn solid fuel. [NFPA 54:12.6.5.1] 802.5.8.1 Gas and Liquid Fuel-Burning Appliances. Where one chimney serves gas appliances and liquid fuel-burning appliances, the appliances shall be connected through separate openings or connected through a single opening where joined by a suitable fitting located as close as practical to the chimney. Where two or more openings are provided into one chimney flue, they shall be at different levels.

• CRC § 2-8 High relevance — show source text

  Residential-type appliance. An approved chimney for removing the products of combustion from fuel-burning, residential-type appliances producing combustion gases not in excess of 1,000°F (538°C) under normal operating conditions, and capable of producing combustion gases of 1,400°F (760°C) during intermittent forces firing for periods up to 1 hour. All temperatures shall be measured at the appliance flue outlet. Residential-type appliance chimneys include masonry and factory-built types.

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  DEFINITIONS

  CHRONICALLY ILL. See “TERMINALLY ILL.”

  [MP] CIRCUIT VENT. A vent that connects to a horizontal drainage branch and vents two traps to not more than eight traps or trapped fixtures connected into a battery.

  [MP] CIRCULATING HOT WATER SYSTEM. A specifically designed water distribution system where one or more pumps are operated in the service hot water piping to circulate heated water from the water-heating equipment to fixtures and back to the water-heating equipment.

  [RB] CLADDING. The exterior materials that cover the surface of the building envelope that is directly loaded by the wind.

  [MP] CLEANOUT. An access opening in the drainage system utilized for the removal of obstructions. Types of cleanouts include a removable plug or cap, and a removable fixture or fixture trap.

  [RE] CLIMATE ZONE. A geographical region based on climatic criteria as specified in this code.

  [RB] CLOSET. A small room or chamber used for storage.

  [RB] COLLAPSIBLE SOILS. Soils that exhibit volumetric reduction in response to partial or full wetting under load.

  [MP] COLLECTION PIPE. Unpressurized pipe used within the collection system that drains on-site nonpotable water or rainwater to a storage tank by gravity.

  [MP] COMBINATION WASTE AND VENT SYSTEM. A specially designed system of waste piping embodying the horizontal wet venting of one or more sinks, lavatories or floor drains by means of a common waste and vent pipe adequately sized to provide free movement of air above the flow line of the drain.

  [RB] COMBUSTIBLE MATERIAL. Any material not defined as noncombustible.

  [MP] COMBUSTION AIR. The air provided to fuel-burning equipment including air for fuel combustion, draft hood dilution and ventilation of the equipment enclosure.

  [RB] COMPRESSIBLE SOILS. Soils that exhibit volumetric reduction in response to the application of load even in the absence of wetting or drying.

  [MP] CONDENSATE. The liquid that separates from a gas due to a reduction in temperature; for example, water that condenses from flue gases and water that condenses from air circulating through the cooling coil in air conditioning equipment.

  [MP] CONDENSING APPLIANCE. An appliance that condenses water generated by the burning of fuels.

  [RB] CONDITIONED AIR. Air treated to control its temperature, relative humidity or quality.

• CRC § 11.5 High relevance — show source text

  R1003.11.5 Oil-fired appliances approved for use with Type L vent. Flue lining and vent systems for use in masonry chimneys with oil-fired appliances approved for use with Type L vent shall be limited to the following:

  1. Flue lining systems complying with Section R1003.11.1.
  2. Listed chimney liners complying with UL 641 (see Section R1003.11.6 for marking).

  R1003.11.6 Notice of usage. Where a flue is relined with a material not complying with Section R1003.11.1, the chimney shall be plainly and permanently identified by a label attached to a wall, ceiling or other conspicuous location adjacent to where the connector enters the chimney. The label shall include the following message or equivalent language:

  THIS CHIMNEY FLUE IS FOR USE ONLY WITH [TYPE OR CATEGORY OF APPLIANCE] APPLIANCES THAT BURN [TYPE OF FUEL]. DO NOT CONNECT OTHER TYPES OF APPLIANCES.

  R1003.12 Clay flue lining (installation). Clay flue liners shall be installed in accordance with ASTM C1283 and extend from a point not less than 8 inches (203 mm) below the lowest inlet or, in the case of fireplaces, from the top of the smoke chamber to a point above the enclosing walls. The lining shall be carried up vertically, with a slope not greater than 30 degrees (0.52 rad) from the vertical.

  Clay flue liners shall be laid in medium-duty water insoluble refractory mortar conforming to ASTM C199 with tight mortar joints left smooth on the inside and installed to maintain an airspace or insulation not to exceed the thickness of the flue liner separating the flue liners from the interior face of the chimney masonry walls. Flue liners shall be supported on all sides. Only enough mortar shall be placed to make the joint and hold the liners in position.

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  CHIMNEYS AND FIREPLACES

  R1003.12.1 Listed materials. Listed materials used as flue linings shall be installed in accordance with the terms of their listings and manufacturer’s instructions.

  R1003.12.2 Space around lining. The space surrounding a chimney lining system or vent installed within a masonry chimney shall not be used to vent any other appliance.

  Exception: This shall not prevent the installation of a separate flue lining in accordance with the manufacturer’s instructions.

  R1003.13 Multiple flues. Where two or more flues are located in the same chimney, masonry wythes shall be built between adjacent flue linings. The masonry wythes shall be not less than 4 inches (102 mm) thick and bonded into the walls of the chimney.

  Exception: Where venting only one appliance, two flues shall be permitted to adjoin each other in the same chimney with only the flue lining separation between them. The joints of the adjacent flue linings shall be staggered not less than 4 inches (102 mm).

  R1003.14 Flue area (appliance). Chimney flues shall not be smaller in area than that of the area of the connector from the appliance

  [see Tables R1003.14(1) and R1003.14(2)]. The sizing of a chimney flue to which multiple appliance venting systems are connected shall be in accordance with the California Mechanical Code.

• CRC § 25.4 High relevance — show source text

  R1003.13 Multiple flues. Where two or more flues are located in the same chimney, masonry wythes shall be built between adjacent flue linings. The masonry wythes shall be not less than 4 inches (102 mm) thick and bonded into the walls of the chimney.

  Exception: Where venting only one appliance, two flues shall be permitted to adjoin each other in the same chimney with only the flue lining separation between them. The joints of the adjacent flue linings shall be staggered not less than 4 inches (102 mm).

  R1003.14 Flue area (appliance). Chimney flues shall not be smaller in area than that of the area of the connector from the appliance

  [see Tables R1003.14(1) and R1003.14(2)]. The sizing of a chimney flue to which multiple appliance venting systems are connected shall be in accordance with the California Mechanical Code.

  TABLE R1003.14(1)—NET CROSS-SECTIONAL AREA OF ROUND FLUE SIZESa	Col2
  ** FLUE SIZE, INSIDE DIAMETER (inches)**	** CROSS-SECTIONAL AREA (square inches)**
  6	28
  7	38
  8	50
  10	78
  103/4	90
  12	113
  15	176
  18	254
  For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2. a. Flue sizes are based on ASTM C315.	For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2. a. Flue sizes are based on ASTM C315.

  TABLE R1003.14(2)—NET CROSS-SECTIONAL AREA OF SQUARE AND RECTANGULAR FLUE SIZES	Col2
  ** FLUE SIZE, OUTSIDE NOMINAL DIMENSIONS (inches)**	** CROSS-SECTIONAL AREA (square inches)**
  4.5 × 8.5	23
  4.5 × 13	34
  8 × 8	42
  8.5 × 8.5	49
  8 × 12	67
  8.5 × 13	76
  12 × 12	102
  8.5 × 18	101
  13 × 13	127
  12 × 16	131
  13 × 18	173
  16 × 16	181
  16 × 20	222
  18 × 18	233
  20 × 20	298
  20 × 24	335
  24 × 24	431
  For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2.	For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2.

  R1003.15 Flue area (masonry fireplace). Flue sizing for chimneys serving fireplaces shall be in accordance with Section R1003.15.1 or R1003.15.2.

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  CHIMNEYS AND FIREPLACES

• CRC § 12.6.2.1 High relevance — show source text

  ** A chimney for residential-type or low-heat appliances shall extend at least 3 feet (914 mm) above the highest point where it passes through a roof of a building and at least 2 feet (610 mm) higher than any portion of a building within a horizontal distance of 10 feet (3048 mm). [NFPA 54:12.6.2.1] (See Figure 802.5.4) 802.5.4.1 Medium-Heat Gas Appliances. A chimney for medium-heat appliances shall extend at least 10 feet (3048 mm) higher than any portion of any building within 25 feet (7620 mm). [NFPA 54:12.6.2.2]

  802.5.4.2 Chimney Height. A chimney shall extend at least 5 feet (1524 mm) above the highest connected appliance draft hood outlet or flue collar.

  [NFPA 54:12.6.2.3]

  802.5.4.3 Decorative Shrouds. Decorative

  shrouds shall not be installed at the termination of factory-built chimneys except where such shrouds are

  listed and labeled for use with the specific factorybuilt chimney system and are installed in accordance with the manufacturer’s installation instructions.

  [NFPA 54:12.6.2.4]

  802.5.5 Size of Chimneys. The effective area of a chimney venting system serving listed appliances with draft hoods, Category I appliances, and other appliances listed for use with Type B vents shall be in accordance with one of the following methods:

  (1) Those listed in Section 803.0.

  (2) The effective areas of the vent connector and chimney flue of a venting system serving a single appliance with a draft hood shall be not less than the area

  of the appliance flue collar or draft hood outlet or greater than seven times the draft hood outlet area.

  (3) The effective area of the chimney flue of a venting system serving two appliances with draft hoods shall be not less than the area of the larger draft hood outlet plus 50 percent of the area of the smaller draft hood outlet or greater than seven times the smaller draft hood outlet area.

  (4) Chimney venting systems using mechanical draft shall be sized in accordance with engineering methods.

  (5) Other engineering methods. [NFPA 54:12.6.3.1]

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  CHIMNEYS AND VENTS

  FIGURE 802.5.4

  TYPICAL TERMINATION LOCATIONS FOR

  CHIMNEYS AND SINGLE-WALL METAL PIPES SERVING

  RESIDENTIAL-TYPE AND LOW-HEAT APPLIANCE

  [NFPA 54: FIGURE A.12.6.2.1]

  802.5.6 Inspection of Chimneys or Vents. This inspection shall be made after chimneys, vents, or parts thereof, authorized by the permit, have been installed and before such vent or part thereof has been covered or concealed.

• CRC § 12.4.5.2 Medium relevance — show source text

  (2) The vent system shall be installed such that no fittings or joints between sections are installed in the above-ceiling space.

  (3) The venting system shall be installed in a conduit or enclosure with joints between the interior of the enclosure and the ceiling space sealed. [NFPA 54:12.4.5.2] 802.4 Type of Venting System to be Used. The type of venting system to be used shall be in accordance with Table 802.4. [NFPA 54:12.5.1]

  802.4.1 Plastic Piping. Where plastic piping is used to vent an appliance, the appliance shall be listed for use with such venting materials and the appliance manufacturer’s installation instructions shall identify the specific plastic piping material. The plastic pipe venting materials shall be labeled in accordance with the product standards specified by the appliance manufacturer or shall be listed and labeled in accordance with UL 1738. [NFPA 54:12.5.2]

  802.4.2 Plastic Vent Joints. Plastic pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions. Plastic pipe venting materials listed and labeled in accordance with UL 1738 shall be installed in accordance

  with the vent manufacturer’s installation instructions. Where primer is required, it shall be of a contrasting color.

  [NFPA 54:12.5.3]

  802.4.3 Special Gas Vents. Special gas vents shall be listed and labeled in accordance with UL 1738 and installed in accordance with the special gas vent manufacturer’s installation instructions. [NFPA 54:12.5.4]

  802.5 Masonry, Metal, and Factory-Built Chimneys. Chimneys shall be installed in accordance with Section 802.5.1 through Section 802.5.3.

  802.5.1 Factory-Built Chimneys. Factory-built chimneys shall be listed in accordance with UL 103, UL 959, or UL 2561. Factory-built chimneys used to vent appliances that operate at positive vent pressure shall be listed for such application. [NFPA 54:12.6.1.1]

  802.5.1.1 Decorative Shrouds. Decorative shrouds addressed in Section 802.5.4.3 shall comply with UL 103 for factory-built residential chimneys, UL 127 for factory-built fireplaces, or UL 1482 for solid-fuel room heaters.

  802.5.2 Metal Chimneys. Metal chimneys shall be built and installed in accordance with NFPA 211. [NFPA 54:12.6.1.2]

  802.5.3 Masonry Chimneys. Masonry chimneys shall be built and installed in accordance with NFPA 211 and lined with one of the following:

  (1) Approved clay flue lining.

  (2) A chimney lining system listed and labeled in accordance with UL 1777.

  (3) Other approved material that resists corrosion, erosion, softening, or cracking from vent gases at temperatures up to 1800°F (982°C).

  Exception: Masonry chimney flues lined with a chimney lining system specifically listed for use with listed appliances with draft hoods, Category I appliances, and

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  CHIMNEYS AND VENTS

• CRC § 0.79 Medium relevance — show source text

  [MP] VENT COLLAR. See “Flue collar.”

  [MP] VENT CONNECTOR. That portion of a venting system that connects the flue collar or draft hood of an appliance to a vent.

  [MP] VENT DAMPER DEVICE, AUTOMATIC. A device intended for installation in the venting system, in the outlet of an individual, automatically operated fuel-burning appliance and that is designed to open the venting system automatically where the appliance is in operation and to close off the venting system automatically where the appliance is in a standby or shutdown condition.

  [MP] VENT GASES. Products of combustion from fuel-burning appliances, plus excess air and dilution air, in the venting system above the draft hood or draft regulator.

  [MP] VENT STACK. A vertical vent pipe installed to provide circulation of air to and from the drainage system and that extends through one or more stories.

  [MP] VENT SYSTEM. Piping installed to equalize pneumatic pressure in a drainage system to prevent trap seal loss or blowback due to siphonage or back pressure.

  [RB] VENTILATION. The natural or mechanical process of supplying conditioned or unconditioned air to, or removing such air from,

  any space.

  [MP] VENTING. Removal of combustion products to the outdoors.

  [MP] VENTING SYSTEM. A continuous open passageway from the flue collar of an appliance to the outside atmosphere for the purpose of removing flue or vent gases. A venting system is usually composed of a vent or a chimney and vent connector, if used, assembled to form the open passageway.

  [MP] VERTICAL PIPE. Any pipe or fitting that makes an angle of 45 degrees (0.79 rad) or more with the horizontal.

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  DEFINITIONS

  [RB] VINYL SIDING. A shaped material, made principally from rigid polyvinyl chloride (PVC), that is used to cover exterior walls of buildings.

  [RB] WALL, RETAINING. A wall not laterally supported at the top, that resists lateral soil load and other imposed loads.

  [RB] WALLS. Walls shall be defined as follows:

  Load-bearing wall. A wall supporting any vertical load in addition to its own weight.

  Nonbearing wall. A wall which does not support vertical loads other than its own weight.

  [MP] WASTE. Liquidborne waste that is free of fecal matter.

  [MP] WASTE PIPE OR STACK. Piping that conveys only liquid sewage not containing fecal material.

  [MP] WASTE RECEPTOR. A floor sink, standpipe, hub drain or a floor drain that receives the discharge of one or more indirect waste pipes.

  [MP] WATER DISTRIBUTION SYSTEM. Piping that conveys water from the service to the plumbing fixtures, appliances, appurtenances, equipment, devices or other systems served, including fittings and control valves.

  [MP] WATER HEATER. Any heating appliance or equipment that heats potable water and supplies such water to the potable hot water distribution system.

  [MP] WATER MAIN. A water supply pipe for public use.

• CRC § 9-4 Medium relevance — show source text

  R904 Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4

  R905 Requirements for Roof Coverings . . . . . . . . . . . . . . . . 9-4

  R906 Roof Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R907 Rooftop-Mounted Photovoltaic Panel Systems . . . 9-19

  R908 Reroofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R909 Roof Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-20

  CHAPTER 10 CHIMNEYS AND FIREPLACES . . . . . . . . . . . .10-3

  R1001 Masonry Fireplaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3

  R1002 Masonry Heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

  R1003 Masonry Chimneys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7

  R1004 Factory-Built Fireplaces. . . . . . . . . . . . . . . . . . . . . . . . 10-12

  R1005 Factory-Built Chimneys . . . . . . . . . . . . . . . . . . . . . . . . 10-12

  R1006 Exterior Air Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-12

  Part IV—Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . .11-1

  Part V—Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-1

  Part VI—Fuel Gas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24-1

  Part VII—Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25-1

  Part VIII—Electrical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34-1

  Part IX— Referenced Standards . . . . . . . . . . . . . . . . . . . . . .44-3

  CHAPTER 44 REFERENCED STANDARDS . . . . . . . . . . . . . .44-3

• CRC § 12.14.1 Medium relevance — show source text

  placing the appliance in service. Balancing baffles shall be listed in accordance with UL 378. [NFPA 54:12.14.1 – 12.14.3]

  802.14 Automatically Operated Vent Dampers. An automatically operated vent damper shall be listed. [NFPA 54:12.15]

  802.14.1 Listing. Automatically operated vent dampers for oil-fired appliances shall comply with UL 17. The automatic damper control shall comply with UL 378.

  802.15 Obstruction of Flow. Devices that retard the flow of vent gases shall not be installed in a vent connector, chimney, or vent. The following shall not be considered as obstructions:

  (1) Draft regulators and safety controls specifically listed for installation in venting systems and installed in accordance with the manufacturer’s installation instructions.

  (2) Approved draft regulators and safety controls designed and installed in accordance with engineering methods.

  (3) Listed heat reclaimers and automatically operated vent dampers installed in accordance with the manufacturers’ installation instructions.

  (4) Vent dampers serving listed appliances installed in accordance with Section 803.1 or Section 803.2 or engineering methods.

  (5) Approved economizers, heat reclaimers, and recuperators installed in venting systems of appliances not required to be equipped with draft hoods, provided the appliance manufacturer’s instructions cover the installation of such a device in the venting system and performance in accordance with Section 802.3 and Section

  802.3.1 is obtained. [NFPA 54:12.16]

  803.0 Sizing of Category I Venting Systems.

  803.1 Additional Requirements to Single Appliance Vent. Venting Table 803.1.2(1) through Table 803.1.2(6) shall not be used where obstructions are installed in the venting system. The installation of vents serving listed appliances with vent dampers shall be in accordance with the appliance manufacturer’s instructions or in accordance with the following:

  (1) The maximum capacity of the vent system shall be determined using the “NAT Max” column.

  (2) The minimum capacity shall be determined as though the appliance were a fan-assisted appliance, using the “FAN Min” column to determine the minimum capacity of the vent system. Where the corresponding “FAN Min” is “NA,” the vent configuration shall not be permitted and an alternative venting configuration shall be utilized.

  [NFPA 54:13.1.1]

  803.1.1 Vent Downsizing. Where the vent size determined from the tables is smaller than the appliance draft hood outlet or flue collar, the use of the smaller size shall be permitted, provided that the installation complies with all of the following requirements:

  «

  «

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  CHIMNEYS AND VENTS

  (1) The total vent height ( H ) is at least 10 feet (3048 mm).

  (2) Vents for appliance draft hood outlets or flue collars 12 inches (305mm) in diameter or smaller are not reduced more than one table size.

  (3) Vents for appliance draft hood outlets or flue collars larger than 12 inches (305 mm) in diameter are not reduced more than two table sizes.

• CRC § 8-3 Medium relevance — show source text

  R802 Wood Roof Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3

  R803 Roof Sheathing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-30

  R804 Cold-Formed Steel Roof Framing . . . . . . . . . . . . . . . 8-31

  R805 Ceiling Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-44

  R806 Roof Ventilation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-44

  R807 Attic Access. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-46

  CHAPTER 9 ROOF ASSEMBLIES . . . . . . . . . . . . . . . . . . . . . .9-3

  R901 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3

  R902 Fire Classification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3

  R903 Weather Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4

  R904 Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4

  R905 Requirements for Roof Coverings . . . . . . . . . . . . . . . . 9-4

  R906 Roof Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R907 Rooftop-Mounted Photovoltaic Panel Systems . . . 9-19

  R908 Reroofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R909 Roof Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-20

  CHAPTER 10 CHIMNEYS AND FIREPLACES . . . . . . . . . . . .10-3

  R1001 Masonry Fireplaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3

  R1002 Masonry Heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

  R1003 Masonry Chimneys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7

• CRC § 10-8 Medium relevance — show source text

  10-8 2025 CALIFORNIA RESIDENTIAL CODE

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  CHIMNEYS AND FIREPLACES

  R1003.12.1 Listed materials. Listed materials used as flue linings shall be installed in accordance with the terms of their listings and manufacturer’s instructions.

  R1003.12.2 Space around lining. The space surrounding a chimney lining system or vent installed within a masonry chimney shall not be used to vent any other appliance.

  Exception: This shall not prevent the installation of a separate flue lining in accordance with the manufacturer’s instructions.

  R1003.13 Multiple flues. Where two or more flues are located in the same chimney, masonry wythes shall be built between adjacent flue linings. The masonry wythes shall be not less than 4 inches (102 mm) thick and bonded into the walls of the chimney.

  Exception: Where venting only one appliance, two flues shall be permitted to adjoin each other in the same chimney with only the flue lining separation between them. The joints of the adjacent flue linings shall be staggered not less than 4 inches (102 mm).

  R1003.14 Flue area (appliance). Chimney flues shall not be smaller in area than that of the area of the connector from the appliance

  [see Tables R1003.14(1) and R1003.14(2)]. The sizing of a chimney flue to which multiple appliance venting systems are connected shall be in accordance with the California Mechanical Code.

  TABLE R1003.14(1)—NET CROSS-SECTIONAL AREA OF ROUND FLUE SIZESa	Col2
  ** FLUE SIZE, INSIDE DIAMETER (inches)**	** CROSS-SECTIONAL AREA (square inches)**
  6	28
  7	38
  8	50
  10	78
  103/4	90
  12	113
  15	176
  18	254
  For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2. a. Flue sizes are based on ASTM C315.	For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2. a. Flue sizes are based on ASTM C315.

• CMC § 2025 Medium relevance — show source text

  Systems that carry nonabrasive exhaust, such as smoke, moderate abrasives such as sawdust, and high abrasives such as manganese or acid vapors use product-conveying ducts. Part II provides the minimum fire safety requirements related to the design, installation, inspection, and maintenance of grease-type operations, such as cooking, for both fuel-gas and solid fuel. Cooking produces a significant amount of smoke, fumes, vapors, heat, and other pollutants. Therefore, acceptable kitchen ventilation is necessary to prevent fires from the build-up of grease and to provide the occupants protection from smoke, unpleasant odors, pollutants, and dangerous gases. There are two types of exhaust hoods (Type I and Type II) used in commercial kitchen applications.

  xiv 2025 CALIFORNIA MECHANICAL CODE

  ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

  FORMAT OF THE UNIFORM MECHANICAL CODE

  Type I hoods are intended to be installed above equipment or appliances that generate grease or smoke. Type II hoods are intended to be installed above equipment or appliances that generate steam, vapor, heat, or odors and do not generate grease or smoke.

  Chapter 6 Duct Systems. Chapter 6 regulates requirements for ducts and plenums that are portions of a heating, cooling, ventilation, or exhaust system. This chapter contains material and installation requirements for metal, gypsum, factory-made, flexible, and plastic ducts. It also contains provisions for duct insulation, dampers, fire protection, and automatic shutoff for the building’s air distribution system. It is worth noting that exhaust ducts are regulated by Chapter 5, and combustion air ducts are regulated by Chapter 7.

  Chapter 7 Combustion Air. Chapter 7 regulates combustion air requirements for ventilation and dilution of flue gases for appliances installed in buildings. Fuel-gas appliances not regulated by chapter include direct vent appliances and Type I clothes dryers. Makeup air requirements for Type I clothes dryers are located in Chapter 5. Chapter 7 provides acceptable methods for supplying satisfactory combustion air to ensure proper combustion. Combustion air can be supplied by using indoor combustion air or by introducing the air from the outdoors.

  Combustion is the rapid oxidation of fuel to release energy. The oxygen required to release the energy from the fuel normally comes from the air. Incomplete combustion of fuel occurs when inadequate oxygen is provided to the appliance. Combustion is needed to provide ventilation cooling for the casing and internal controls. When a lack of oxygen occurs, some of the carbon is not oxidized, and carbon monoxide forms.

  Chapter 8 Chimneys and Vents. Chapter 8 regulates the installation, design, and construction of venting systems for fuel-burning appliances. The provisions addressed within this chapter follow procedures an installer would use to design or evaluate a venting system. Many requirements apply to the design and construction of venting systems, chimneys, installation of gas vents, and the sizing of venting system for a Category I appliance. Sizing venting systems require rigorous engineering calculations. However, the venting sizing requirements and sizing tables in this chapter already perform the calculations for the benefit of the end user.

  Combustion appliances produce products of incomplete combustion, including potentially harmful carbon monoxide (CO). It is desirable to vent these products to the outdoors. Although the gas is clean-burning fuel, the products of combustion must not be allowed to collect within a building.