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

• CRC § 1.20 High relevance — show source text

  Actual lengths of the sides of the circumscribed rectangle shall be rounded to the next highest unit of 10 when using this table.
  d. For Exposure Category C, multiply bracing units by a factor of 1.20 for a one-story building, 1.30 for a two-story building and 1.40 for a three-story building.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447m/s.
  a. Interpolation shall not be permitted.
  b. Cripple walls or wood-framed basement walls in a walk-out condition shall be designated as the first story and the stories above shall be redesignated as the second and third
  stories, respectively, and shall be prohibited in a three-story structure.
  c. Actual lengths of the sides of the circumscribed rectangle shall be rounded to the next highest unit of 10 when using this table.
  d. For Exposure Category C, multiply bracing units by a factor of 1.20 for a one-story building, 1.30 for a two-story building and 1.40 for a three-story building.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447m/s.
  a. Interpolation shall not be permitted.
  b. Cripple walls or wood-framed basement walls in a walk-out condition shall be designated as the first story and the stories above shall be redesignated as the second and third
  stories, respectively, and shall be prohibited in a three-story structure.
  c. Actual lengths of the sides of the circumscribed rectangle shall be rounded to the next highest unit of 10 when using this table.
  d. For Exposure Category C, multiply bracing units by a factor of 1.20 for a one-story building, 1.30 for a two-story building and 1.40 for a three-story building.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447m/s.
  a. Interpolation shall not be permitted.
  b. Cripple walls or wood-framed basement walls in a walk-out condition shall be designated as the first story and the stories above shall be redesignated as the second and third
  stories, respectively, and shall be prohibited in a three-story structure.
  c. Actual lengths of the sides of the circumscribed rectangle shall be rounded to the next highest unit of 10 when using this table.
  d. For Exposure Category C, multiply bracing units by a factor of 1.20 for a one-story building, 1.30 for a two-story building and 1.40 for a three-story building.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447m/s.
  a. Interpolation shall not be permitted.
  b. Cripple walls or wood-framed basement walls in a walk-out condition shall be designated as the first story and the stories above shall be redesignated as the second and third
  stories, respectively, and shall be prohibited in a three-story structure.
  c. Actual lengths of the sides of the circumscribed rectangle shall be rounded to the next highest unit of 10 when using this table.
  d. For Exposure Category C, multiply bracing units by a factor of 1.20 for a one-story building, 1.30 for a two-story building and 1.40 for a three-story building.|

• CRC § 7.3 High relevance — show source text

  3|7.3|9.9|14.6| |26|NP|NP|NP|NP|13.2|22.4|NP|NP|5.0|8.5|11.4|16.9| |28|NP|NP|NP|NP|15.1|25.7|NP|NP|5.7|9.7|13.1|19.4| |30|NP|NP|NP|NP|17.2|NP|NP|NP|6.5|11.0|14.9|22.0| |32|NP|NP|NP|NP|19.4|NP|NP|NP|7.3|12.4|16.8|24.8| |34|NP|NP|NP|NP|21.7|NP|NP|NP|8.2|13.9|18.8|NP| |36|NP|NP|NP|NP|24.1|NP|NP|NP|9.1|15.4|20.9|NP| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
  NP = Not Permitted. Pressure loss exceeds reasonable limits.
  a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
  b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
  100 feet.
  c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
  NP = Not Permitted. Pressure loss exceeds reasonable limits.
  a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
  b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
  100 feet.
  c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
  NP = Not Permitted. Pressure loss exceeds reasonable limits.
  a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
  b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
  100 feet.
  c. Flow rate from Section P2904.4.2.

• CRC § 0.266 High relevance — show source text

  099 × 0.266 head diameter)|4|3| |60|24/0|3/8|8d common
  (21/2 × 0.131 × 0.281 head diameter)|6|4| |70|24/16|7/16|8d common
  (21/2× 0.131 × 0.281 head diameter)|4|4| |70|24/16|7/16|10d box
  (3 × 0.128 × 0.312 head diameter)|6|4| |80|24/16|7/16|8d common
  (21/2 × 0.131 × 0.281 head diameter)|4|4| |80|24/16|7/16|10d box
  (3 × 0.128 × 0.312 head diameter)|6|4| |90|32/16|15/32|8d common
  (21/2 × 0.131 × 0.281 head diameter)|4|3| |90|32/16|15/32|10d box
  (3 × 0.128 × 0.312 head diameter)|6|4| |For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
  a. Fasteners shall comply with Sections R703.3.2 and R703.3.3.
  b. Maximum spacing of exterior soffit framing members shall not exceed 24 inches.
  c. Wood structural panels shall be of an exterior exposure grade.
  d. Wood structural panels shall be installed with strength axis perpendicular to supports with not fewer than two continuous spans.
  e. Fastener spacing applies where wood exterior soffit framing member-specific gravity is 0.42 or larger. Where the specific gravity of exterior soffit framing members is greater
  than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, the fastener spacing shall be multiplied by 0.67 or the same fastener spacing as prescribed for galvanized
  steel nails shall be permitted to be used where RSRS-01 (2-inch by 0.099-inch by 0.266-inch head) nails replace 6d box nails and RSRS-03 (21/2-inch × 0.131-inch × 0.281-inch
  head) nails replace 8d common nails or 10d box nails. RSRS is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667. Framing members shall be mini-
  mum 2 × 3 nominal with the larger dimension in the cross section aligning with the length of fasteners to provide sufficient embedment depths.
  f. Spacing at intermediate supports shall be not greater than 12 inches on center.|For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
  a. Fasteners shall comply with Sections R703.3.2 and R703.3.3.
  b. Maximum spacing of exterior soffit framing members shall not exceed 24 inches.
  c. Wood structural panels shall be of an exterior exposure grade.
  d. Wood structural panels shall be installed with strength axis perpendicular to supports with not fewer than two continuous spans.
  e. Fastener spacing applies where wood exterior soffit framing member-specific gravity is 0.42 or larger.

• CRC § 0.42 High relevance — show source text

  Fastener spacing applies where wood exterior soffit framing member-specific gravity is 0.42 or larger. Where the specific gravity of exterior soffit framing members is greater
  than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, the fastener spacing shall be multiplied by 0.67 or the same fastener spacing as prescribed for galvanized
  steel nails shall be permitted to be used where RSRS-01 (2-inch by 0.099-inch by 0.266-inch head) nails replace 6d box nails and RSRS-03 (21/2-inch × 0.131-inch × 0.281-inch
  head) nails replace 8d common nails or 10d box nails. RSRS is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667. Framing members shall be mini-
  mum 2 × 3 nominal with the larger dimension in the cross section aligning with the length of fasteners to provide sufficient embedment depths.
  f. Spacing at intermediate supports shall be not greater than 12 inches on center.|For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
  a. Fasteners shall comply with Sections R703.3.2 and R703.3.3.
  b. Maximum spacing of exterior soffit framing members shall not exceed 24 inches.
  c. Wood structural panels shall be of an exterior exposure grade.
  d. Wood structural panels shall be installed with strength axis perpendicular to supports with not fewer than two continuous spans.
  e. Fastener spacing applies where wood exterior soffit framing member-specific gravity is 0.42 or larger. Where the specific gravity of exterior soffit framing members is greater
  than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, the fastener spacing shall be multiplied by 0.67 or the same fastener spacing as prescribed for galvanized
  steel nails shall be permitted to be used where RSRS-01 (2-inch by 0.099-inch by 0.266-inch head) nails replace 6d box nails and RSRS-03 (21/2-inch × 0.131-inch × 0.281-inch
  head) nails replace 8d common nails or 10d box nails. RSRS is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667. Framing members shall be mini-
  mum 2 × 3 nominal with the larger dimension in the cross section aligning with the length of fasteners to provide sufficient embedment depths.
  f. Spacing at intermediate supports shall be not greater than 12 inches on center.|For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
  a. Fasteners shall comply with Sections R703.3.2 and R703.3.3.
  b. Maximum spacing of exterior soffit framing members shall not exceed 24 inches.
  c. Wood structural panels shall be of an exterior exposure grade.
  d. Wood structural panels shall be installed with strength axis perpendicular to supports with not fewer than two continuous spans.
  e. Fastener spacing applies where wood exterior soffit framing member-specific gravity is 0.42 or larger.

• CRC § 17.4 High relevance — show source text

  8|17.4|1.5|2.5|3.4|5.1|0.6|1.0|1.3|1.9| |10|7.7|13.1|17.8|26.3|2.3|3.8|5.2|7.7|0.8|1.4|2.0|2.9| |12|10.8|18.4|24.9|NP|3.2|5.4|7.3|10.7|1.2|2.0|2.7|4.0| |14|14.4|24.5|NP|NP|4.2|7.1|9.6|14.3|1.6|2.7|3.6|5.4| |16|18.4|NP|NP|NP|5.4|9.1|12.4|18.3|2.0|3.4|4.7|6.9| |18|22.9|NP|NP|NP|6.7|11.4|15.4|22.7|2.5|4.3|5.8|8.6| |20|27.8|NP|NP|NP|8.1|13.8|18.7|27.6|3.1|5.2|7.0|10.4| |22|NP|NP|NP|NP|9.7|16.5|22.3|NP|3.7|6.2|8.4|12.4| |24|NP|NP|NP|NP|11.4|19.3|26.2|NP|4.3|7.3|9.9|14.6| |26|NP|NP|NP|NP|13.2|22.4|NP|NP|5.0|8.5|11.4|16.9| |28|NP|NP|NP|NP|15.1|25.7|NP|NP|5.7|9.7|13.1|19.4| |30|NP|NP|NP|NP|17.2|NP|NP|NP|6.5|11.0|14.9|22.0| |32|NP|NP|NP|NP|19.4|NP|NP|NP|7.3|12.4|16.8|24.8| |34|NP|NP|NP|NP|21.7|NP|NP|NP|8.2|13.9|18.8|NP| |36|NP|NP|NP|NP|24.1|NP|NP|NP|9.1|15.4|20.9|NP| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
  NP = Not Permitted. Pressure loss exceeds reasonable limits.
  a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
  b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
  100 feet.
  c. Flow rate from Section P2904.4.2.

• CRC § 0.099 High relevance — show source text

  c, d, e	Col2	Col3	Col4	Col5	Col6
  MAXIMUM DESIGN PRESSURE (+ or - psf)	MINIMUM PANEL SPAN RATING	MINIMUM PANEL PERFORMANCE CATEGORY	NAIL TYPE AND SIZE	FASTENERa SPACINGe ALONG EDGES AND INTERMEDIATE SUPPORTS (inches)	FASTENERa SPACINGe ALONG EDGES AND INTERMEDIATE SUPPORTS (inches)
  MAXIMUM DESIGN PRESSURE (+ or - psf)	MINIMUM PANEL SPAN RATING	MINIMUM PANEL PERFORMANCE CATEGORY	NAIL TYPE AND SIZE	Galvanized Steel	Stainless Steel
  30	24/0	3/8	6d box (2 × 0.099 × 0.266 head diameter)	6f	4
  40	24/0	3/8	6d box (2 × 0.099 × 0.266 head diameter)	6	4
  50	24/0	3/8	6d box (2 × 0.099 × 0.266 head diameter)	4	4
  50	24/0	3/8	8d common (21/2 × 0.131 × 0.281 head diameter)	6	6
  60	24/0	3/8	6d box (2 × 0.099 × 0.266 head diameter)	4	3
  60	24/0	3/8	8d common (21/2 × 0.131 × 0.281 head diameter)	6	4
  70	24/16	7/16	8d common (21/2× 0.131 × 0.281 head diameter)	4	4
  70	24/16	7/16	10d box (3 × 0.128 × 0.312 head diameter)	6	4
  80	24/16	7/16	8d common (21/2 × 0.131 × 0.281 head diameter)	4	4
  80	24/16	7/16	10d box (3 × 0.128 × 0.312 head diameter)	6	4
  90	32/16	15/32	8d common (21/2 × 0.131 × 0.281 head diameter)	4	3
  90	32/16	15/32	10d box (3 × 0.128 × 0.312 head diameter)	6	4
  For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa. a. Fasteners shall comply with Sections R703.3.2 and R703.3.3. b. Maximum spacing of exterior soffit framing members shall not exceed 24 inches. c. Wood structural panels shall be of an exterior exposure grade. d. Wood structural panels shall be installed with strength axis perpendicular to supports with not fewer than two continuous spans. e.

• CRC § 0.42 High relevance — show source text

  Spacing of fasteners not included in this table shall be based on Table R602.3(2).
  f. For wood structural panel roof sheathing attached to gable end roof framing and to intermediate supports within 48 inches of roof edges and ridges, nails shall be spaced at 4
  inches on center where the ultimate design wind speed is greater than 130 mph in Exposure B or greater than 110 mph in Exposure C. Fastener spacing applies where roof
  framing specific gravity is 0.42 or larger. Where roof framing specific gravity is greater than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, fastening of roof
  sheathing shall be with RSRS-03 (21/2″ × 0.131″ × 0.281″ head) nails.
  g. Gypsum sheathing shall conform to ASTM C1396 and shall be installed in accordance with ASTM C1280 or GA 253 . Fiberboard sheathing shall conform to ASTM C208.
  h. Spacing of fasteners on floor sheathing panel edges applies to panel edges supported by framing members and required blocking and at floor perimeters only. Spacing of fasteners
  on roof sheathing panel edges applies to panel edges supported by framing members and required blocking. Blocking of roof or floor sheathing panel edges perpendicular to the
  framing members need not be provided except as required by other provisions of this code. Floor perimeter shall be supported by framing members or solid blocking.
  i. Where a rafter is fastened to an adjacent parallel ceiling joist in accordance with this schedule, provide two toe nails on one side of the rafter and toe nails from the ceiling joist
  to top plate in accordance with this schedule. The toe nail on the opposite side of the rafter shall not be required.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447 m/s; 1 ksi = 6.895 MPa.
  a. Nails are smooth-common, box or deformed shanks except where otherwise stated. Nails used for framing and sheathing connections are carbon steel and shall have mini-
  mum average bending yield strengths as shown: 80 ksi for shank diameter of 0.192 inch (20d common nail), 90 ksi for shank diameters larger than 0.142 inch but not larger than
  0.177 inch, and 100 ksi for shank diameters of 0.142 inch or less. Connections using nails and staples of other materials, such as stainless steel, shall be designed by accepted
  engineering practice or approved under Section R104.2.2.
  b. RSRS-01 is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667.
  c. Nails shall be spaced at not more than 6 inches on center at all supports where spans are 48 inches or greater.
  d. Four-foot by 8-foot or 4-foot by 9-foot panels shall be applied vertically.
  e. Spacing of fasteners not included in this table shall be based on Table R602.3(2).
  f. For wood structural panel roof sheathing attached to gable end roof framing and to intermediate supports within 48 inches of roof edges and ridges, nails shall be spaced at 4
  inches on center where the ultimate design wind speed is greater than 130 mph in Exposure B or greater than 110 mph in Exposure C. Fastener spacing applies where roof
  framing specific gravity is 0.42 or larger.

• 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

  10-12 2025 CALIFORNIA RESIDENTIAL CODE

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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.

  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.

  2025 CALIFORNIA RESIDENTIAL CODE 10-13

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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 § 2025 High relevance — show source text

  It is important to understand that the IRC contains coverage for what is conventional and common in residential construction practice. While the IRC will provide all of the needed coverage for most residential construction, it might not address construction practices and systems that are atypical or rarely encountered in the industry. Therefore, the IRC contains several references to other codes either as an alternative to the provisions of the IRC or where the IRC lacks coverage for a particular type of structure, design, system, appliance or method of construction. In other words, the IRC is meant to be all inclusive for typical residential construction and it relies on other codes only where alternatives are desired or where the code lacks coverage for the uncommon aspect of residential construction. Of course, the IRC constantly evolves to address new technologies and construction practices that were once uncommon, but are now common.

  The IRC is unique in that much of it, including Chapters 3 through 9 and Chapters 34 through 43, is presented in an ordered format that is consistent with the normal progression of construction, starting with the design phase and continuing through the final trimout phase. This is consistent with the “cookbook” philosophy of the IRC.

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  xiv 2025 CALIFORNIA RESIDENTIAL CODE

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  Arrangement and Format of the 2025 CRC

  The CRC is divided into nine main parts, specifically: Part I—Administrative, Part II—Definitions, Part III—Building Planning and Construction, Part IV—Energy Conservation, Part V—Mechanical, Part VI—Fuel Gas, Part VII—Plumbing, Part VIII—Electrical and Part IX—Referenced Standards. Parts IV through VIII of IRC are not adopted in California and replaced with references to appropriate parts of Title 24. The following provides a brief description of the content of each chapter and appendix of the CRC:

  Chapter 1 Scope and Administration.

  Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.

  Chapter 2 Definitions.

  Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.

  Chapter 3 Building Planning.

  Chapter 3 provides guidelines for a minimum level of structural integrity, life safety, fire safety and livability for inhabitants of dwelling units regulated by this code. Chapter 3 is a compilation of the code requirements specific to the building planning sector of the design and construction process. This chapter sets forth code requirements dealing with light, ventilation, sanitation, minimum room size, ceiling height and environmental comfort. Chapter 3 establishes life-safety provisions including limitations on glazing used in hazardous areas, specifications on stairways, use of guards at elevated surfaces, window and fall protection, and rules for means of egress. Snow, wind and seismic design live and dead loads and flood-resistant construction, as well as solar energy systems are addressed in this chapter.

  Chapter 4 Foundations.

• CRC § 1.2. High relevance — show source text

  1.2. If the addition constitutes substantial improvement, the existing building and the addition shall comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable. 1.3. If the addition does not constitute substantial improvement, the addition is not required to comply with the flood design requirements for new construction, provided that both of the following apply: 1.3.1. The addition shall not create or extend any nonconformity of the existing building with the flood-resistant construction requirements. 1.3.2. The lowest floor of the addition shall be at or above the lower of the lowest floor of the existing building or the lowest floor elevation required in Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable. 2. For horizontal additions that are not structurally interconnected to the existing building: 2.1. The addition shall comply with Section 1612 of the California Building Code, or Section R306 of the California Resi- dential Code, as applicable. 2.2. If the addition and all other proposed work, when combined, constitute substantial improvement, the existing building and the addition shall comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable. 3. For vertical additions and all other proposed work that, when combined, constitute substantial improvement, the existing building shall comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable. 4. For a new foundation, replacement foundation or a foundation raised or extended upward, the foundation shall comply with Section 1612 of the California Building Code, or Section R306 of the California Residential Code, as applicable.

  SECTION 1104—ENERGY CONSERVATION

  1104.1 Minimum requirements. Additions to existing buildings shall comply with applicable provisions of the California Energy Code (Part 6, Title 24, C.C.R).

  11-4 2025 CALIFORNIA EXISTING BUILDING CODE

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  12 HISTORIC BUILDINGS

  Chapter 12 is not adopted by the State of California.

  Historic buildings and structures shall comply with Part 8, Title 24, California Code of Regulations.

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  CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

  CHAPTER 13 – PERFORMANCE COMPLIANCE METHODS

  Not adopted by the State of California (May be available for adoption by local ordinance. See Section 1.1.11.) (See Section 104.11 for consideration of alternative means of compliance.)

• CRC § 110.4 High relevance — show source text

  A heat pump pool heater as the primary heating system that meets the sizing requirements of Reference Joint Appendix JA16.3. The control for the heat pump pool heater shall meet the requirements specified in Title 24, Part 6, Section 110.4(d). The supplementary heater can be of any energy source; or 3. A heating system that derives at least 60 percent of the annual heating energy from on-site renewable energy or on-site recovered energy; or 4. A combination of a solar pool heating system and heat pump pool heater without any additional supplementary heater; or 5. A pool heating system determined by the Energy Commission Executive Director to use no more energy than the systems specified in Item 1, 2, 3, or 4 above.

  Exception 1 to A4.204.1.2: Portable electric spas compliant with 20 CCR, Section 1605.3(g)(7) of the Appliance Efficiency Regulations.

  Exception 2 to A4.204.1.2: A pool or spa that is heated solely by a solar pool heating system without any supplementary heater.

  Exception 3 to A4.204.1.2: An existing building with inadequate Solar Access Roof Area (SARA) as specified in Title 24, Part 6, Section 170.2(f) for a solar pool heating system to be installed.

  Exception 4 to A4.204.1.2: Heating systems which are used exclusively for permanent spa applications in existing buildings with gas availability.

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25402, 25402.1, 25402.4 and 25402.8, Public Resources Code.

  2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A4-11

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  APPENDIX A4-12 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

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  A4 RESIDENTIAL VOLUNTARY MEASURES

  DIVISION A4.3 – WATER EFFICIENCY AND CONSERVATION

  SECTION A4.301—GENERAL (RESERVED)

  SECTION A4.302—DEFINITIONS (RESERVED)

  SECTION A4.303—INDOOR WATER USE

  A4.303.1 Kitchen faucets. The maximum flow rate of kitchen faucets shall not exceed 1.5 gallons per minute at 60 psi. Kitchen faucets may temporarily increase the flow above the maximum rate, but not to exceed 2.2 gallons per minute at 60 psi, and must default to a maximum flow rate of 1.5 gallons per minute at 60 psi.

  Note: Where complying faucets are unavailable, aerators or other means may be used to achieve reduction.

  A4.303.2 Alternate water sources for nonpotable applications. Alternate nonpotable water sources are used for indoor potable water reduction. Alternate nonpotable water sources shall be installed in accordance with the California Plumbing Code.

  A4.303.3 Appliances. Install at least one qualified ENERGY STAR dishwasher or clothes washer.

  Note: See Section A5.303.3 for nonresidential dishwashers and clothes washers.

• CRC § 100.0 Medium relevance — show source text

  2025 CRC Residential Code

  Converted from PDF using pymupdf4llm Source: 2025 CRC Residential Code.pdf Text ratio: 100.0% Conversion date: 2025-10-05 02:35:50

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

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

  2025 California Residential Code California Code of Regulations, Title 24, Part 2.5

  COPYRIGHT  2025

  by INTERNATIONAL CODE COUNCIL, INC.

  For information on use rights and permissions, please contact:

  of the International Code Council, Inc., and/or its licensors (as applicable), and may not be used without permission.

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

  PREFACE

  This document is Part 2.5 of thirteen parts of the official triennial compilation and publication of the adoptions, amendments and repeal of administrative regulations to California Code of Regulations, Title 24, also referred to as the California Building Standards Code. This part is known as the California Residential Code.

  The California Building Standards Code is published in its entirety every three years by order of the California legislature, with supplements published in intervening years. The California legislature delegated authority to various state agencies, boards, commissions and departments to create building regulations to implement the State’s statutes. These building regulations, or standards, have the same force of law, and take effect 180 days after their publication unless otherwise stipulated. The Califor- nia Building Standards Code applies to occupancies in the State of California as annotated.

  A city, county, or city and county may establish more restrictive building standards reasonably necessary because of local climatic, geological or topographical conditions. Findings of the local condition(s) and the adopted local building standard(s) must generally be filed with the California Building Standards Commission (or other filing if indicated) to become effective, and may not be effective sooner than the effective date of this edition of the California Building Standards Code . Local building standards that were adopted and applicable to previous editions of the California Building Standards Code do not apply to this edition without appropriate adoption and the required filing.

  Should you find publication (e.g., typographical) errors or inconsistencies in this code or wish to offer comments toward improving its format, please address your comments to:

  California Building Standards Commission

  2525 Natomas Park Drive, Suite 130 Sacramento, CA 95833-2936

  Phone: (916) 263-0916 Email: cbsc@dgs.ca.gov

  Web page: www.dgs.ca.gov/bsc

  ACKNOWLEDGMENTS

  The 2025 California Building Standards Code (Code) was developed through the outstanding collaborative efforts of the Department of Housing and Community Development, Division of the State Architect, Office of the State Fire Marshal, Department of Health Care Access and Information, California Energy Commission, California Department of Public Health, California State Lands Commission, Board of State and Community Corrections, Department of Water Resources, State Historical Building Safety Board, Department of Consumer Affairs, State Librarian, Department of Food and Agriculture, and the California Building Standards Commission (Commission).

  This collaborative effort included the assistance of the Commission’s Code Advisory Committees and many other volunteers who worked tirelessly to assist the Commission in the production of this Code.

  Governor Gavin Newsom

  Members of the California Building Standards Commission