Floors on ground, decks and cold-formed steel framing

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

• California Residential Code High relevance — show source text

  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.

  Chapter 4 provides the requirements for the design and construction of foundation systems for buildings regulated by this code. Provisions for seismic load, flood load and frost protection are contained in this chapter. A foundation system consists of two interdependent components: the foundation structure itself and the supporting soil.

  The prescriptive provisions of this chapter provide requirements for constructing footings and walls for foundations of wood, masonry, concrete and precast concrete. In addition to a foundation’s ability to support the required design loads, this chapter addresses several other factors that can affect foundation performance. These include controlling surface water and subsurface drainage, requiring soil tests where conditions warrant and evaluating proximity to slopes and minimum depth requirements. The chapter also provides requirements to minimize adverse effects of moisture, decay and pests in basements and crawl spaces.

  Chapter 5 Floors.

  Chapter 5 provides the requirements for the design and construction of floor systems that will be capable of supporting minimum required design loads. This chapter covers four different types: wood floor framing, wood floors on the ground, cold-formed steel floor framing and concrete slabs on the ground. Allowable span tables are provided that greatly simplify the determination of joist, girder and sheathing sizes for raised floor systems of wood framing and cold-formed steel framing. This chapter also contains prescriptive requirements for wood-framed exterior decks and their attachment to the main building.

  Chapter 6 Wall Construction.

  Chapter 6 contains provisions that regulate the design and construction of walls. The wall construction covered in Chapter 6 consists of five different types: wood framed, cold-formed steel framed, masonry, concrete and structural insulated panel (SIP). The primary concern of this chapter is the structural integrity of wall construction and transfer of all imposed loads to the supporting structure. This chapter provides the requirements for the design and construction of wall systems that are capable of supporting the minimum design vertical loads (dead, live and snow loads) and lateral loads (wind or seismic loads). This chapter contains the prescriptive requirements for wall bracing and/or shear walls to resist t

• CRC § 2025 High relevance — show source text

  The prescriptive provisions of this chapter provide requirements for constructing footings and walls for foundations of wood, masonry, concrete and precast concrete. In addition to a foundation’s ability to support the required design loads, this chapter addresses several other factors that can affect foundation performance. These include controlling surface water and subsurface drainage, requiring soil tests where conditions warrant and evaluating proximity to slopes and minimum depth requirements. The chapter also provides requirements to minimize adverse effects of moisture, decay and pests in basements and crawl spaces.

  Chapter 5 Floors.

  Chapter 5 provides the requirements for the design and construction of floor systems that will be capable of supporting minimum required design loads. This chapter covers four different types: wood floor framing, wood floors on the ground, cold-formed steel floor framing and concrete slabs on the ground. Allowable span tables are provided that greatly simplify the determination of joist, girder and sheathing sizes for raised floor systems of wood framing and cold-formed steel framing. This chapter also contains prescriptive requirements for wood-framed exterior decks and their attachment to the main building.

  Chapter 6 Wall Construction.

  Chapter 6 contains provisions that regulate the design and construction of walls. The wall construction covered in Chapter 6 consists of five different types: wood framed, cold-formed steel framed, masonry, concrete and structural insulated panel (SIP). The primary concern of this chapter is the structural integrity of wall construction and transfer of all imposed loads to the supporting structure. This chapter provides the requirements for the design and construction of wall systems that are capable of supporting the minimum design vertical loads (dead, live and snow loads) and lateral loads (wind or seismic loads). This chapter contains the prescriptive requirements for wall bracing and/or shear walls to resist the imposed lateral loads due to wind and seismic activity.

  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.

• CRC § 5-14 High relevance — show source text

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  FLOORS

  R505.2 Structural framing. Load-bearing cold-formed steel floor framing members shall be in accordance with this section.

  R505.2.1 Material. Load-bearing cold-formed steel framing members shall be cold formed to shape from structural quality sheet steel complying with the requirements of AISI S240, Section A3.

  R505.2.2 Corrosion protection. Load-bearing cold-formed steel framing shall have a metallic coating complying with AISI S240, Section A4.

  R505.2.3 Dimension, thickness and material grade. Load-bearing cold-formed steel floor framing members shall comply with AISI S230, Section A4.3 and material grade requirements as specified in AISI S230, Section A4.4.

  R505.2.4 Identification. Load-bearing cold-formed steel framing members shall meet the product identification requirements of AISI S240, Section A5.5.

  R505.2.5 Fastening. Screws for steel-to-steel connections shall be installed with a minimum edge distance and center-to-center spacing of [1] / 2 inch (12.7 mm), shall be self-drilling tapping, and shall conform to ASTM C1513. Floor sheathing shall be attached to cold-formed steel joists with minimum No. 8 self-drilling tapping screws that conform to ASTM C1513. Screws attaching floor sheathing to cold-formed steel joists shall have a minimum head diameter of 0.292 inch (7.4 mm) with countersunk heads and shall be installed with a minimum edge distance of [3] / 8 inch (9.5 mm). Gypsum board ceilings shall be attached to cold-formed steel joists with minimum No. 6 screws conforming to ASTM C954 or ASTM C1513 with a bugle-head style and shall be installed in accordance with Section R702. For all connections, screws shall extend through the steel not fewer than three exposed threads. Fasteners shall have a rust-inhibitive coating suitable for the installation in which they are being used, or be manufactured from material not susceptible to corrosion.

  R505.2.6 Web holes, web hole reinforcing and web hole patching. Web holes in floor framing members shall comply with the conditions as prescribed in AISI S230, Section A4.5. Web holes not in compliance with the conditions as prescribed in AISI S230, Section A4.5 shall be reinforced in accordance with the provisions of AISI S230, Section A4.6 or patched in accordance with the provisions of AISI S230, Section A4.7.

  R505.3 Floor construction. Cold-formed steel floors shall be constructed in accordance with this section.

  R505.3.1 Floor-to-foundation or load-bearing wall connections. Cold-formed steel-framed floors shall be anchored to foundations, wood sills or load-bearing walls in accordance with Table R505.3.1(1) and Figure R505.3.1(1), R505.3.1(2), R505.3.1(3), R505.3.1(4), R505.3.1(5) or R505.3.1(6). Anchor bolts shall be located not more than 12 inches (305 mm) from corners or the termination of bottom tracks.

• CRC § 5-1 High relevance — show source text

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

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  5 FLOORS

  User notes:

  About this chapter: Chapter 5 provides the requirements for the design and construction of floor systems that will be capable of supporting minimum required design loads. This chapter covers wood floor framing, wood floors on the ground, cold-formed steel floor framing and concrete slabs on the ground. Allowable span tables are provided that greatly simplify the determination of joist, girder and sheathing sizes for raised floor systems of wood framing and cold-formed steel framing. This chapter also contains prescriptive requirements for wood-framed exterior decks and their attachment to the main building.

  SECTION R501—GENERAL

  R501.1 Application. The provisions of this chapter shall control the design and construction of the floors for buildings, including the floors of attic spaces used to house mechanical or plumbing fixtures and equipment.

  R501.2 Requirements. Floor construction shall be capable of accommodating all loads in accordance with Section R301 and of transmitting the resulting loads to the supporting structural elements.

  SECTION R502—WOOD FLOOR FRAMING

  R502.1 General. Wood and wood-based products used for load-supporting purposes shall conform to the applicable provisions of this section.

  R502.1.1 Sawn lumber. Sawn lumber shall be identified by a grade mark of an accredited lumber grading or inspection agency and have design values certified by an accreditation body that complies with DOC PS 20. In lieu of a grade mark, a certificate of inspection issued by a lumber grading or inspection agency meeting the requirements of this section shall be accepted.

  Note: See Section R301.1.1.1 for limited-density owner- built rural dwellings.

  R502.1.1.1 Preservative-treated lumber. Preservative treated dimension lumber shall be identified as required by Section R304.2.

  R502.1.1.2 End-jointed lumber. Approved end-jointed lumber identified by a grade mark conforming to Section R502.1.1 shall be permitted to be used interchangeably with solid-sawn members of the same species and grade. End-jointed lumber used in an assembly required elsewhere in this code to have a fire-resistance rating shall have the designation “Heat-Resistant Adhesive” or “HRA” included in its grade mark.

  R502.1.2 Prefabricated wood I-joists. Structural capacities and design provisions for prefabricated wood I-joists shall be established and monitored in accordance with ASTM D5055.

  R502.1.3 Structural glued-laminated timbers. Glued-laminated timbers shall be manufactured and identified as required in ANSI A190.1, ANSI 117 and ASTM D3737.

  R502.1.4 Structural log members. Structural log members shall comply with the provisions of ICC 400.

  R502.1.5 Structural composite lumber. Structural capacities for structural composite lumber shall be established and monitored in accordance with ASTM D5456.

  R502.1.6 Cross-laminated timber. Cross-laminated timber shall be manufactured and identified as required by ANSI/APA PRG 320.

• CRC § 4-6 High relevance — show source text

  R403 Footings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

  R404 Foundation and Retaining Walls . . . . . . . . . . . . . . . . 4-24

  R405 Foundation Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . 4-42

  R406 Foundation Waterproofing and Dampproofing . . . 4-43

  R407 Columns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-44

  R408 Under-Floor Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-44

  CHAPTER 5 FLOORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

  R501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

  R502 Wood Floor Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

  R503 Floor Sheathing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12

  R504 Pressure Preservative-Treated Wood

  Floors (On Ground) . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

  R505 Cold-Formed Steel Floor Framing . . . . . . . . . . . . . . . 5-14

  R506 Concrete Floors (On Ground) . . . . . . . . . . . . . . . . . . . 5-26

  R507 Exterior Decks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26

  CHAPTER 6 WALL CONSTRUCTION. . . . . . . . . . . . . . . . . . . 6-3

  R601 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

  R602 Wood Wall Framing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

  R603 Cold-Formed Steel Wall Framing. . . . . . . . . . . . . . . . 6-53

  R604 Wood Structural Panels . . . . . . . . . . . . . . . . . . . . . . . . 6-93

  R605 Particleboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-93

  R606 General Masonry Construction. . . . . . . . . . . . . . . . . . 6-93

• CRC § 5-14 High relevance — show source text

  Floors (On Ground) . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

  R505 Cold-Formed Steel Floor Framing . . . . . . . . . . . . . . . 5-14

  R506 Concrete Floors (On Ground) . . . . . . . . . . . . . . . . . . . 5-26

  R507 Exterior Decks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26

  CHAPTER 6 WALL CONSTRUCTION. . . . . . . . . . . . . . . . . . . 6-3

  R601 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

  R602 Wood Wall Framing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

  R603 Cold-Formed Steel Wall Framing. . . . . . . . . . . . . . . . 6-53

  R604 Wood Structural Panels . . . . . . . . . . . . . . . . . . . . . . . . 6-93

  R605 Particleboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-93

  R606 General Masonry Construction. . . . . . . . . . . . . . . . . . 6-93

  R607 Glass Unit Masonry . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-106

  R608 Exterior Concrete Wall Construction. . . . . . . . . . . . 6-107

  R609 Exterior Windows and Doors. . . . . . . . . . . . . . . . . . . 6-172

  R610 Structural Insulated Panel Wall Construction . . . 6-175

  CHAPTER 7 WALL COVERING. . . . . . . . . . . . . . . . . . . . . . . . 7-3

  R701 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3

  R702 Interior Covering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3

  R703 Exterior Wall Covering . . . . . . . . . . . . . . . . . . . . . . . . . 7-10

  R704 Exterior Soffits and Fascias. . . . . . . . . . . . . . . . . . . . . 7-32

  R705 BIPV Systems for Exterior Wall Coverings and Fenestration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-35

  CHAPTER 8 ROOF-CEILING CONSTRUCTION. . . . . . . . . . . 8-3

• CRC § 2.6 Medium relevance — show source text

  Gypsum board ceilings shall be attached to cold-formed steel joists with minimum No. 6 screws conforming to ASTM C954 or ASTM C1513 with a bugle-head style and shall be installed in accordance with Section R702. For all connections, screws shall extend through the steel not fewer than three exposed threads. Fasteners shall have a rust-inhibitive coating suitable for the installation in which they are being used, or be manufactured from material not susceptible to corrosion.

  R505.2.6 Web holes, web hole reinforcing and web hole patching. Web holes in floor framing members shall comply with the conditions as prescribed in AISI S230, Section A4.5. Web holes not in compliance with the conditions as prescribed in AISI S230, Section A4.5 shall be reinforced in accordance with the provisions of AISI S230, Section A4.6 or patched in accordance with the provisions of AISI S230, Section A4.7.

  R505.3 Floor construction. Cold-formed steel floors shall be constructed in accordance with this section.

  R505.3.1 Floor-to-foundation or load-bearing wall connections. Cold-formed steel-framed floors shall be anchored to foundations, wood sills or load-bearing walls in accordance with Table R505.3.1(1) and Figure R505.3.1(1), R505.3.1(2), R505.3.1(3), R505.3.1(4), R505.3.1(5) or R505.3.1(6). Anchor bolts shall be located not more than 12 inches (305 mm) from corners or the termination of bottom tracks. Continuous cold-formed steel joists supported by interior load-bearing walls shall be constructed in accordance with Figure R505.3.1(7). Lapped cold-formed steel joists shall be constructed in accordance with Figure R505.3.1(8). End floor joists constructed on foundation walls parallel to the joist span shall be doubled unless a C-shaped bearing stiffener, sized in accordance with Section R505.3.4, is installed web-to-web with the floor joist beneath each supported wall stud, as shown in Figure R505.3.1(9). Fastening of cold-formed steel joists to other framing members shall be in accordance with Section R505.2.5 and Table R505.3.1(2).

  TABLE R505.3.1(1)—FLOOR-TO-FOUNDATION OR BEARING WALL CONNECTION REQUIREMENTSa, b	Col2	Col3
  ** FRAMING CONDITION**	** BASIC ULTIMATE WIND SPEED (mph) AND EXPOSURE**	** BASIC ULTIMATE WIND SPEED (mph) AND EXPOSURE**
  ** FRAMING CONDITION**	** 110 mph Exposure Category C or** less than 139 mph Exposure Category B	** Less than 139 mph Exposure Category C**
  Floor joist to wall track of exterior wall in accor- dance with Figure R505.3.1(1)	2-No. 8 screws	3-No. 8 screws
  Rim track or end joist to load-bearing wall top track in accordance with Figure R505.3.1(1)	1-No. 8 screw at 24 inches o.c.	1-No. 8 screw at 24 inches o.c.
  Rim track or end joist to wood sill in accordance with Figure R505.3.1(2)	Steel plate spaced at 4 feet o.c. with 4-No.

• CRC § 25.4 Medium relevance — show source text

  Other maximum span provided by an accredited lumber grading or inspection agency also allowed.
  c. Individual wood deck boards supported by two joists shall be considered single span and three or more joists shall be considered multiple span.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 degree = 0.01745 rad.
  a. Maximum angle of 45 degrees from perpendicular for wood deck boards.
  b. Other maximum span provided by an accredited lumber grading or inspection agency also allowed.
  c. Individual wood deck boards supported by two joists shall be considered single span and three or more joists shall be considered multiple span.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 degree = 0.01745 rad.
  a. Maximum angle of 45 degrees from perpendicular for wood deck boards.
  b. Other maximum span provided by an accredited lumber grading or inspection agency also allowed.
  c. Individual wood deck boards supported by two joists shall be considered single span and three or more joists shall be considered multiple span.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 degree = 0.01745 rad.
  a. Maximum angle of 45 degrees from perpendicular for wood deck boards.
  b. Other maximum span provided by an accredited lumber grading or inspection agency also allowed.
  c. Individual wood deck boards supported by two joists shall be considered single span and three or more joists shall be considered multiple span.|

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  FLOORS

  R507.8 Vertical and lateral supports. Where supported by attachment to an exterior wall, decks shall be positively anchored to the primary structure and designed for both vertical and lateral loads. Such attachment shall not be accomplished by the use of toenails or nails subject to withdrawal. For decks with cantilevered framing members, connection to exterior walls or other framing members shall be designed and constructed to resist uplift resulting from the full live load specified in Table R301.5 acting on the cantilevered portion of the deck. Where positive connection to the primary building structure cannot be verified during inspection, decks shall be self-supporting.

  R507.9 Vertical and lateral supports at band joist. Vertical and lateral supports for decks shall comply with this section.

  R507.9.1 Vertical supports. Vertical loads shall be transferred to band joists with ledgers in accordance with this section.

  R507.9.1.1 Ledger details. Deck ledgers shall be a minimum 2-inch by 8-inch (51 mm by 203 mm) nominal, No. 2 grade or better pressure-preservative-treated Southern pine, incised pressure-preservative-treated hem-fir, or decay-resistant, naturally durable wood. Deck ledgers shall not support concentrated loads from beams or girders. Deck ledgers shall not be supported on stone or masonry veneer.

  R507.9.1.2 Band joist details. Band joists supporting a ledger shall be a minimum 2-inch-nominal (51 mm), solid-sawn, spruce-pine-fir or better lumber or a minimum 1-inch (25 mm) nominal engineered wood rim boards in accordance with Section R502.1.7. Band joists shall bear fully on the primary structure capable of supporting all required loads.

• CRC § 1.1 Medium relevance — show source text

  SECTION R505—COLD-FORMED STEEL FLOOR FRAMING

  R505.1 Cold-formed steel floor framing. Elements shall be straight and free of any defects that would significantly affect structural performance. Cold-formed steel floor framing members shall be in accordance with the requirements of this section.

  R505.1.1 Applicability limits. The provisions of this section shall control the construction of cold-formed steel floor framing for buildings not greater than 60 feet (18 288 mm) in length perpendicular to the joist span, not greater than 40 feet (12 192 mm) in width parallel to the joist span and less than or equal to three stories above grade plane. Cold-formed steel floor framing constructed in accordance with the provisions of this section shall be limited to sites where the ultimate design wind speed is less than 140 miles per hour (63 m/s), Exposure Category B or C, and the ground snow load is less than or equal to 70 pounds per square foot (3.35 kPa).

  R505.1.1.1 Alternate applications. Cold-formed steel floor framing for buildings exceeding the applicability limits of Section R505.1.1 is permitted to be designed and constructed in accordance with AISI S230, subject to the limits therein.

  R505.1.2 In-line framing. Where supported by cold-formed steel-framed walls in accordance with Section R603, cold-formed steel floor framing shall be constructed with floor joists located in-line with load-bearing studs located below the joists in accordance with the tolerances specified in AISI S240, Section B1.2.3.

  R505.1.3 Floor trusses. Cold-formed steel trusses shall be designed, braced and installed in accordance with AISI S230, Section D8. In the absence of specific bracing requirements, trusses shall be braced in accordance with accepted industry practices, such as the SBCA Cold-Formed Steel Building Component Safety Information (CFSBCSI), Guide to Good Practice for Handling, Installing & Bracing of Cold-Formed Steel Trusses . Truss members shall not be notched, cut or altered in any manner without an approved design.

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  FLOORS

  R505.2 Structural framing. Load-bearing cold-formed steel floor framing members shall be in accordance with this section.

  R505.2.1 Material. Load-bearing cold-formed steel framing members shall be cold formed to shape from structural quality sheet steel complying with the requirements of AISI S240, Section A3.

  R505.2.2 Corrosion protection. Load-bearing cold-formed steel framing shall have a metallic coating complying with AISI S240, Section A4.

  R505.2.3 Dimension, thickness and material grade. Load-bearing cold-formed steel floor framing members shall comply with AISI S230, Section A4.3 and material grade requirements as specified in AISI S230, Section A4.4.

  R505.2.4 Identification. Load-bearing cold-formed steel framing members shall meet the product identification requirements of AISI S240, Section A5.5.

  R505.2.5 Fastening. Screws for steel-to-steel connections shall be installed with a minimum edge distance and center-to-center spacing of [1] / 2 inch (12.7 mm), shall be self-drilling tapping, and shall conform to ASTM C1513.

• CRC § 25.4 Medium relevance — show source text

  For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

  (TYP.)

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  FLOORS

  SECTION R506—CONCRETE FLOORS (ON GROUND)

  R506.1 General. Concrete slab-on-ground floors shall be designed and constructed in accordance with the provisions of this section or ACI 332. Such floors shall be not less than 3 [1] / 2 inches (89 mm) thick (for expansive soils, see Section R403.1.8). The specified compressive strength of concrete shall be as set forth in Section R402.2.

  R506.2 Post-tensioned slab-on-ground floors. Post-tensioned concrete slabs-on-ground floors placed on expansive or stable soils shall be designed in accordance with PTI DC10.5.

  R506.3 Site preparation. The area within the foundation walls shall have all vegetation, topsoil and foreign material removed.

  R506.3.1 Fill. Fill material shall be free of vegetation and foreign material. The fill shall be compacted to ensure uniform support of the slab, and except where approved, the fill depths shall not exceed 24 inches (610 mm) for clean sand or gravel and 8 inches (203 mm) for earth.

  R506.3.2 Base. A 4-inch-thick (102 mm) base course consisting of clean graded sand, gravel, crushed stone, crushed concrete or crushed blast-furnace slag passing a 2-inch (51 mm) sieve shall be placed on the prepared subgrade where the slab is below grade.

  Exception: A base course is not required where the concrete slab is installed on well-drained or sand-gravel mixture soils classified as Group I according to the United Soil Classification System in accordance with Table R401.4.1(2).

  R506.3.3 Vapor retarder. A minimum 6 mil (0.006 inch; 152 μ m) polyethylene or approved vapor retarder with joints lapped not less than 6 inches (152 mm) shall be placed between the concrete floor slab and the base course or the prepared subgrade where a base course does not exist.

  Exception: The vapor retarder is not required for the following:

  1. Garages, utility buildings and other unheated accessory structures.
  2. For unheated storage rooms having an area of less than 70 square feet (6.5 m [2] ) and carports.
  3. Driveways, walks, patios and other flatwork not likely to be enclosed and heated at a later date.
  4. Where approved by the building official, based on local site conditions.

  R506.3.3.1 Capillary break. When a vapor retarder is required, a capillary break shall be installed in accordance with the Califor- nia Green Building Standards Code, Chapter 4, Division 4.5.

  R506.3.4 Reinforcement support. Where provided in slabs-on-ground, reinforcement shall be supported to remain in place from the center to upper one-third of the slab for the duration of the concrete placement.

  SECTION R507—EXTERIOR DECKS

• CRC § 2.95 Medium relevance — show source text

  00|2.95|2.20|1.45|3.00|2.35|1.25|DR| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#8 screw into 33 mil steel or
  thicker|8|3.00|2.55|1.60|0.60|3.00|1.80|DR|DR| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#8 screw into 33 mil steel or
  thicker|12|3.00|1.80|DR|DR|3.00|0.65|DR|DR| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#10 screw into 33 mil steel|6|4.00|3.50|2.70|1.95|4.00|2.90|1.70|0.55| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#10 screw into 33 mil steel|8|4.00|3.10|2.05|1.00|4.00|2.25|0.70|DR| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#10 screw into 33 mil steel|12|4.00|2.25|0.70|DR|3.70|1.05|DR|DR| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#10 screw into 43 mil steel or
  thicker|6|4.00|4.00|4.00|3.60|4.00|4.00|3.45|2.70| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#10 screw into 43 mil steel or
  thicker|8|4.00|4.00|3.70|3.00|4.00|3.85|2.80|1.80| |Cold-formed steel framing
  (minimum penetration of steel
  thickness plus 3 threads)|#10 screw into 43 mil steel or
  thicker|12|4.00|3.85|2.80|1.80|4.00|3.05|1.50|DR| |For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
  DR = design required, o.c. = on center.
  a. Cold-formed steel framing shall be minimum 33 ksi steel for 33 mil and 43 mil steel and 50 ksi steel for 54 mil steel or thicker.
  b. Screws shall comply with the requirements of AISI S240.
  c. Foam sheathing shall have a minimum compressive strength of 15 pounds per square inch in accordance with ASTM C578 or ASTM C1289.|For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
  DR = design required, o.c. = on center.
  a. Cold-formed steel framing shall be minimum 33 ksi steel for 33 mil and 43 mil steel and 50 ksi steel for 54 mil steel or thicker.
  b.

• CRC § 2.3.1 Medium relevance — show source text

  2025 CALIFORNIA RESIDENTIAL CODE APPENDIX CK-7

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

  APPENDIX CK-8 2025 CALIFORNIA RESIDENTIAL CODE

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

  2025 CALIFORNIA RESIDENTIAL CODE APPENDIX NA-1

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  APPENDIX NA-2 2025 CALIFORNIA RESIDENTIAL CODE

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

  Concrete Capillary break R506.2.3.1 Compressive strength R402.2 Floors (on ground) R506 Tile (roof) R905.3 Weathering Figure R301.2(1), R402.2 Construction

  3D-printed Appendix BM Cavity wall masonry R608 Cob Appendix BK Extended plate walls Appendix BN Flood-resistant R306

  Floors Chapter 5 Footings R403 Foundation material R402

  Foundation walls R404

  Foundations Chapter 4 Hemp-lime Appendix BL Masonry R606, R607, R608, R610 Pollutant control R340 Roofs Chapter 8 Steel framing R505, R603, R804 Strawbale Appendix BJ Straw-clay Appendix BI Walls Chapter 6 Waste R334.1 Wood framing R502, R602, R802 Construction Documents R106, R306.3.9

  Court Emergency escape and rescue openings R319.1, R319.2.4 Means of egress R318.1 Natural light R325.1.1 Covering Exterior R703

  Interior R702 Roof Chapter 9 Wall Chapter 7 Crawl Space R408

  Access R408.4

  Damper Fireplace R1001.7.1 Dampproofing R406 Day Care Appendix BD Defined R202 Large family day-care homes R336 Dead Loads R301.4

  Decay Protection against R304 Deck

  Attachment R318.5 Supported by exterior wall R507 Wood/plastic composite boards R507.2.2

  Definitions Building R202 Mechanical system R202 Plumbing R202 Design Criteria R301 Alternative provisions R301.1.1 Application R301.1 Climatic and geographic R301.2 Dead load R301.4

  Deflection R301.6 Engineered design R301.1.3

  Accessibility R322 Accessory Dwelling Unit R202 Authority to Enforce Automatic Fire Sprinkler Systems 1.8.9.1, R313.2 Accessory Structure Elevations R306.3.2

  Energy R330.5 Exterior walls R302.1

  Scope R101.2 Addition (see also Existing Buildings) Carbon monoxide alarms R311.2.2 Change of occupancy R110.1 Construction R302.2.3