CRC · California Residential Code
Factory-built Fireplaces & Chimneys
Chapter 10 of the CRC requires factory-built fireplaces and chimneys to be listed and installed per their listings, applicable UL standards, and manufacturer instructions.
Last reviewed: July 6, 2026
Overview
This hub covers California Residential Code requirements for listed, factory-built fireplace and chimney systems — how they must be tested, listed, installed and vented when used in dwelling units. Chapter 10 organizes these requirements; key provisions include §R1004 (factory-built fireplaces), §R1005 (factory-built chimneys) and §R1006 (exterior combustion‑air supply) which set the listing/testing standards (for example UL 127 for fireplaces and UL 103/UL 959 for chimneys) and installation/termination rules.
The CRC relies largely on the listing-and-labeling approach for factory-built systems: units and components must be installed in accordance with their listings and the manufacturer's instructions (including required clearances, offsets, insulation shields, hearth extensions and limitations on decorative shrouds and gasketed doors). See §R1004.1, §R1004.2, §R1004.5 and §R1005.1–R1005.9 for these specifics.
Definitions and referenced standards are also important: the CRC defines "factory-built fireplace" and "factory-built chimney" and points to the applicable UL standards and other referenced documents used throughout Chapter 10. Consult the definitions and the referenced‑standards list when determining which test standard or marking applies to a given appliance.
In this section
- What limits apply to chimney offsets, insulation shields and elbow counts for factory-built chimneys?
- What limits exist for hearth extensions, gasketed doors and decorative shrouds on factory-built systems?
- What listing, labeling and installation requirements apply to factory-built fireplaces and chimneys?
- What marking and UL requirements apply for factory-built chimneys serving solid-fuel or medium-heat appliances?
Code references
Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:
CRC § 25.4 High relevance — show source text
FIGURE R1003.20—CHIMNEY CRICKET
AIRSPACE
ROOF LINE
For SI: 1 inch = 25.4 mm.
FLUE LINER Col2 Col3 Col4 Col5 1 IN.
AIRS1 IN.
AIRS1 IN.
AIRS1 IN.
AIRS1 IN.
AIRSW W W W W 2025 CALIFORNIA RESIDENTIAL CODE 10-11
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CHIMNEYS AND FIREPLACES
SECTION R1004—FACTORY-BUILT FIREPLACES
R1004.1 General. Factory-built fireplaces shall be listed and labeled and shall be installed in accordance with the conditions of the listing. Factory-built fireplaces shall be tested in accordance with UL 127.
R1004.1.1 Factory-built wood burning fireplaces. Factory-built wood burning fireplaces shall be qualified at the U.S. EPA’s Volun- tary Fireplace Program Phase 2 emissions level and be in accordance with the California Green Building Standards Code, Chapter 4, Division 4.5.
R1004.2 Hearth extensions. Hearth extensions of approved factory-built fireplaces shall be installed in accordance with the listing of the fireplace. The hearth extension shall be readily distinguishable from the surrounding floor area. Listed and labeled hearth extensions shall comply with UL 1618.
R1004.3 Decorative shrouds. Decorative shrouds shall not be installed at the termination of chimneys for factory-built fireplaces except where the shrouds are listed and labeled for use with the specific factory-built fireplace system and installed in accordance with the manufacturer’s instructions.
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.
CRC § 2025 High relevance — show source text
Chapter 9 Roof Assemblies.
Chapter 9 regulates the design and construction of roof assemblies. A roof assembly includes the roof deck, vapor retarder, substrate or thermal barrier, insulation, vapor retarder and roof covering. This chapter provides the requirement for wind resistance of roof coverings.
The types of roof covering materials and installation regulated by Chapter 9 are: asphalt shingles, clay and concrete tile, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shakes and shingles, built-up roofs, metal roof panels, modified bitumen roofing, thermoset and thermoplastic single-ply roofing, sprayed polyurethane foam roofing, liquid applied coatings and photovoltaic shingles. Chapter 9 also provides requirements for roof drainage, flashing, above deck thermal insulation, rooftop-mounted photovoltaic systems and recovering or replacing an existing roof covering.
Chapter 10 Chimneys and Fireplaces.
Chapter 10 contains requirements for the safe construction of masonry chimneys and fireplaces and establishes the 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; the factory-built type relies on the listing and labeling method of approval. Chapter 10 provides the requirements for seismic reinforcing and anchorage of masonry fireplaces and chimneys.
Chapter 11 [RE] Energy Efficiency.
Chapter 11 is not adopted in California. See California Energy Code, Title 24, Part 6.
Chapter 12 Mechanical Administration.
Chapter 12 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 13 General Mechanical System Requirements.
Chapter 13 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 14 Heating and Cooling Equipment and Appliances.
Chapter 14 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 15 Exhaust Systems.
Chapter 15 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 16 Duct Systems.
Chapter 16 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 17 Combustion Air.
Chapter 17 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 18 Chimneys and Vents.
Chapter 18 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 19 Special Appliances, Equipment and Systems.
Chapter 19 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 20 Boilers and Water Heaters.
Chapter 20 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
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Chapter 21 Hydronic Piping.
Chapter 21 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 22 Special Piping and Storage Systems.
Chapter 22 is not adopted in California. See California Mechanical Code, Title 24, Part 4.
Chapter 23 Solar Thermal Energy Systems.
CRC § 2025 High relevance — show source text
Chapter 6 also regulates exterior windows and doors installed in walls. This chapter contains criteria for the performance of exterior windows and doors and includes provisions for testing and labeling, garage doors, windborne debris protection and anchorage details.
Chapter 7 Wall Covering.
Chapter 7 contains provisions for the design and construction of interior and exterior wall coverings. This chapter establishes the various types of materials, materials standards and methods of application permitted for use as interior coverings, including interior plaster, gypsum board, ceramic tile, wood veneer paneling, hardboard paneling, wood shakes and wood shingles. Chapter 7 also contains requirements for the use of vapor retarders for moisture control in walls.
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Exterior wall coverings provide the weather-resistant exterior envelope that protects the building’s interior from the elements. Chapter 7 provides the requirements for wind resistance and water-resistive barrier for exterior wall coverings. This chapter prescribes the exterior wall coverings as well as the water-resistive barrier required beneath the exterior materials. Exterior wall coverings regulated by this section include aluminum, stone and masonry veneer, wood, hardboard, particleboard, wood structural panel siding, wood shakes and shingles, exterior plaster, steel, vinyl, fiber cement and exterior insulation finish systems.
Chapter 8 Roof-Ceiling Construction.
Chapter 8 regulates the design and construction of roof-ceiling systems. This chapter contains two roof-ceiling framing systems: wood framing and cold-formed steel framing. Allowable span tables are provided to simplify the selection of rafter and ceiling joist size for wood roof framing and cold-formed steel framing. Chapter 8 also provides requirements for the application of ceiling finishes, the proper ventilation of concealed spaces in roofs (e.g., enclosed attics and rafter spaces), unvented attic assemblies and attic access.
Chapter 9 Roof Assemblies.
Chapter 9 regulates the design and construction of roof assemblies. A roof assembly includes the roof deck, vapor retarder, substrate or thermal barrier, insulation, vapor retarder and roof covering. This chapter provides the requirement for wind resistance of roof coverings.
The types of roof covering materials and installation regulated by Chapter 9 are: asphalt shingles, clay and concrete tile, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shakes and shingles, built-up roofs, metal roof panels, modified bitumen roofing, thermoset and thermoplastic single-ply roofing, sprayed polyurethane foam roofing, liquid applied coatings and photovoltaic shingles. Chapter 9 also provides requirements for roof drainage, flashing, above deck thermal insulation, rooftop-mounted photovoltaic systems and recovering or replacing an existing roof covering.
Chapter 10 Chimneys and Fireplaces.
Chapter 10 contains requirements for the safe construction of masonry chimneys and fireplaces and establishes the 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; the factory-built type relies on the listing and labeling method of approval. Chapter 10 provides the requirements for seismic reinforcing and anchorage of masonry fireplaces and chimneys.
Chapter 11 [RE] Energy Efficiency.
Chapter 11 is not adopted in California. See California Energy Code, Title 24, Part 6.
Chapter 12 Mechanical Administration.
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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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 § 25.4 High relevance — show source text
br>G||||||||||||||| |FLUE
LINING
FLUE
LINING
G|||||||||||||||R1003.19 Chimney fireblocking. Spaces between chimneys and floors and ceilings through which chimneys pass shall be fireblocked with noncombustible material securely fastened in place. The fireblocking of spaces between chimneys and wood joists, beams or headers shall be self-supporting or be placed on strips of metal or metal lath laid across the spaces between combustible
material and the chimney.
R1003.20 Chimney crickets. Chimneys shall be provided with crickets where the dimension parallel to the ridgeline is greater than
30 inches (762 mm) and does not intersect the ridgeline. The intersection of the cricket and the chimney shall be flashed and counter-
flashed in the same manner as normal roof-chimney intersections. Crickets shall be constructed in compliance with Figure R1003.20
and Table R1003.20.Col2 TABLE R1003.20—CRICKET DIMENSIONS TABLE R1003.20—CRICKET DIMENSIONS ** ROOF SLOPE** ** H** 12:12 1/2 of W 8:12 1/3 of W 6:12 1/4 of W 4:12 1/6 of W 3:12 1/8 of W FIGURE R1003.20—CHIMNEY CRICKET
AIRSPACE
ROOF LINE
For SI: 1 inch = 25.4 mm.
FLUE LINER Col2 Col3 Col4 Col5 1 IN.
AIRS1 IN.
AIRS1 IN.
AIRS1 IN.
AIRS1 IN.
AIRSW W W W W 2025 CALIFORNIA RESIDENTIAL CODE 10-11
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CHIMNEYS AND FIREPLACES
SECTION R1004—FACTORY-BUILT FIREPLACES
R1004.1 General. Factory-built fireplaces shall be listed and labeled and shall be installed in accordance with the conditions of the listing. Factory-built fireplaces shall be tested in accordance with UL 127.
R1004.1.1 Factory-built wood burning fireplaces. Factory-built wood burning fireplaces shall be qualified at the U.S. EPA’s Volun- tary Fireplace Program Phase 2 emissions level and be in accordance with the California Green Building Standards Code, Chapter 4, Division 4.5.
R1004.2 Hearth extensions. Hearth extensions of approved factory-built fireplaces shall be installed in accordance with the listing of the fireplace. The hearth extension shall be readily distinguishable from the surrounding floor area. Listed and labeled hearth extensions shall comply with UL 1618.
CRC § 1001.11 High 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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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 wallsG 6 inches
8 inchesChimney
Vertical reinforcingbH 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 § 1.1 High relevance — show source text
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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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.
R1006.3 Clearance. Unlisted c ombustion air ducts shall be installed with a minimum 1-inch (25 mm) clearance to combustibles for all parts of the duct within 5 feet (1524 mm) of the duct outlet. R1006.4 Passageway. The combustion air passageway shall be not less than 6 square inches (3870 mm [2] ) and not more than 55 square inches (0.035 m [2] ), except that combustion air systems for listed fireplaces shall be constructed in accordance with the fireplace manufacturer’s instructions.
R1006.5 Outlet. The exterior air outlet shall be located in the back or side of the firebox chamber or shall be located outside of the firebox, at the level of the hearth and not greater than 24 inches (610 mm) from the firebox opening. The outlet shall be closable and designed to prevent burning material from dropping into concealed combustible spaces.
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Part IV—Energy Conservation
(Note: Part IV is not adopted. See California Energy Code, Title 24, Part 6.)
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Part V—Mechanical
(Note: Part V is not adopted. See California Mechanical Code, Title 24, Part 4.)
CRC § 9-4 High 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 § 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 § 10-12 High relevance — show source text
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
APPENDIX AA BOARD OF APPEALS. . . . . . . . . . APPENDIX AA-3
AA101 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .APPENDIX AA-3
APPENDIX AB PERMIT FEES. . . . . . . . . . . . . . . . APPENDIX AB-3
AB101 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .APPENDIX AB-3
APPENDIX AC RESERVED . . . . . . . . . . . . . . . . . . APPENDIX AC-1
APPENDIX BA RESERVED . . . . . . . . . . . . . . . . . . APPENDIX BA-1
APPENDIX BB TINY HOUSES . . . . . . . . . . . . . . . APPENDIX BB-3
BB101 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .APPENDIX BB-3
BB102 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . .APPENDIX BB-3
BB103 Ceiling Height . . . . . . . . . . . . . . . . . . . . . . . .APPENDIX BB-3
BB104 Lofts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .APPENDIX BB-3
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 § 0.26 Medium relevance — show source text
EXTERIOR WALL ASSEMBLY. A system or assembly of exterior wall components, including exterior wall covering materials, that provides protection of the building structural members, including framing and sheathing materials, and conditioned interior space, from the detri- mental effects of the exterior environment.
EXTERIOR WALL COVERING. A material or assembly of materials applied on the exterior side of exterior walls for the purpose of providing a weather-resisting barrier, insulation or for aesthetics, including but not limited to, veneers, siding, exterior insulation and finish systems, architectural trim and embellishments such as cornices, soffits, facias, gutters and leaders.
[RB] FACING. The wood structural panel facings that form the two outmost rigid layers of the structural insulated panel.
[MP] FACTORY-BUILT CHIMNEY. A listed and labeled chimney composed of factory-made components assembled in the field in accordance with the manufacturer’s instructions and the conditions of the listing.
[MP] FACTORY-MADE AIR DUCT. A listed and labeled duct manufactured in a factory and assembled in the field in accordance with the manufacturer’s instructions and conditions of the listing.
FAMILY. (HCD 1) An individual or two or more persons who are related by blood or marriage; or otherwise live together in a dwelling unit.
FENESTRATION. Products classified as either vertical fenestration or skylights and sloped glazing, installed in such a manner as to preserve the weather-resistant barrier of the wall or roof in which they are installed. Fenestration includes products with glass or other transparent or translucent materials.
[RE] FENESTRATION, VERTICAL. Windows that are fixed or movable, opaque doors, glazed doors, glazed block and combination opaque and glazed doors installed in a wall at less than 15 degrees (0.26 rad) from vertical.
[RB] FIBER-CEMENT (BACKERBOARD, SIDING, SOFFIT, TRIM AND UNDERLAYMENT) PRODUCTS. Manufactured thin section composites of hydraulic cementitious matrices and discrete nonasbestos fibers.
[RB] FIRE SEPARATION DISTANCE. The distance measured from the building face to one of the following:
To the closest interior lot line.
To the centerline of a street, an alley or public way.
To an imaginary line between two buildings or townhouse units on the lot.
The distance shall be measured at a right angle from the face of the wall.
[RB] FIREBLOCKING. Building materials or materials approved for use as fireblocking, installed to resist the free passage of flame to other areas of the building through concealed spaces.
2-12 2025 CALIFORNIA RESIDENTIAL CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
DEFINITIONS
[RB] FIREPLACE. An assembly consisting of a hearth and fire chamber of noncombustible material and provided with a chimney, for use with solid fuels.
Factory-built fireplace. A listed and labeled fireplace and chimney system composed of factory-made components, and assembled in the field in accordance with manufacturer’s instructions and the conditions of the listing.
Masonry fireplace. A field-constructed fireplace composed of solid masonry units, bricks, stones or concrete.
Frequently asked questions
Do factory-built fireplaces and chimneys have to be listed and installed exactly as the manufacturer prescribes?
Yes. The CRC requires factory-built fireplaces and chimneys to be listed and labeled and installed per the conditions of the listing and manufacturer’s installation instructions (see §R1004.1 and §R1005.1).
Are decorative shrouds or gasketed doors allowed at the chimney or fireplace termination?
Decorative shrouds and gasketed doors are prohibited unless they are specifically listed and labeled for use with that exact factory-built system and installed per the manufacturer’s instructions (see §R1004.3, §R1004.5 and §R1005.2).
Is exterior combustion air required for factory-built fireplaces?
Yes. Factory-built fireplaces must have an exterior air supply to ensure proper combustion unless the room is mechanically ventilated and maintained at neutral or positive pressure; exterior air components for listed fireplaces must be listed components and installed per the manufacturer (see §R1006.1 and §R1006.1.1).
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