CRC · California Residential Code

Which cold-formed steel standards apply to framing and prescriptive methods?

For a homeowner: the CRC tells builders to use specific AISI standards: nonload‑bearing gypsum partitions follow AISI S220 (and studs must be at least 1 1/4" wide), load‑bearing steel members must meet AISI S240 (with engineered design per AISI S100 when required), and the prescriptive AISI S230 tables can be used for one‑ and two‑family homes where the code figures and tables allow it.

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Last reviewed: July 6, 2026

What the code requires — plain English

The California Residential Code requires that the designer or builder use the referenced AISI standards for cold-formed steel depending on whether the framing is prescriptive (AISI S230), nonload-bearing (AISI S220), or load-bearing/engineered (AISI S240 / AISI S100). The specific calls appear in § R608.9.2, § R608.9.3, and § R702.3.3 and are listed in the code’s referenced-standards chapter.

Use AISI S220 for nonload-bearing steel stud framing, AISI S240 (or AISI S100 for design) for load‑bearing/engineered members, and AISI S230 when the prescriptive one‑ and two‑family dwelling method is followed.

Requirements in detail

Key standards called out by the CRC (what to pick)

AISI S220 — nonload-bearing cold‑formed steel framing (referenced in § R702.3.3).
AISI S240 — load‑bearing cold‑formed steel framing and material/identification/corrosion requirements (referenced across floor, roof and wall sections).
AISI S100 — design specification for cold‑formed steel structural members; used where an engineered design is required.
AISI S230 — prescriptive method for cold‑formed steel framing for one‑ and two‑family dwellings (permitted alternative/prescriptive approach where the code allows).

These standards are explicitly listed in the CRC referenced‑standards chapter and are mapped to the CRC sections above.

When the CRC requires each standard (decision rules)

If the member is nonload‑bearing (e.g., interior partitions supporting gypsum), use AISI S220 as required in § R702.3.3.
If the member is load‑bearing (walls, floor/roof framing members), use AISI S240 for material, corrosion protection, identification and manufacturing requirements; AISI S100 governs the design approach when engineered calculations are used (see R608 framing connection options referencing engineered design).
If you follow the CRC’s prescriptive one‑ and two‑family tables and figures for cold‑formed steel framing, AISI S230 is the listed prescriptive standard to be used in lieu of full engineered design where the prescriptive limits and figures apply.

Decision‑relevant dimensions / values

Decision factor	Key value / threshold	Standard to use	Code Reference
Framing function	Nonload‑bearing	AISI S220	§ R702.3.3
Framing function	Load‑bearing	AISI S240 (material/identification/corrosion); design per AISI S100 if engineered	§ R702.3.3; R505 & R804 (floor/roof framing)
Method chosen	Prescriptive (one‑ & two‑family)	AISI S230 (prescriptive method)	§ R301.1.1 and referenced standards list
Applicability limits (floors/roofs)	≤ 60 ft length, ≤ 40 ft width, ≤ 3 stories; Vult < 140 mph; ground snow ≤ 70 psf	Use R505 / R804 or design per AISI S230/S240 as allowed	R505.1.1 and R804.1.1
Gypsum support	Minimum stud width 1 1/4 in	Applies to cold‑formed steel supporting gypsum	§ R702.3.3

How the connection/prescriptive figures tie in

Sections § R608.9.2 and § R608.9.3 let you use the CRC’s prescriptive connection details (Figures R608.9(5)–(12)) for connections between concrete walls and light‑frame floor/ceiling/roof systems; the figures include both wood and cold‑formed‑steel details and specify when the cold‑formed‑steel figures apply “where permitted by the tables accompanying those figures.”
Where the figure tables do not permit prescriptive use, or for conditions outside the applicability limits, the CRC requires proprietary connector design or an engineered design (e.g., per AISI S100 or ASCE 7). § R608.9.2 and § R608.9.3 list these alternative compliance paths.

Exceptions & special cases

The prescriptive figures and tables apply only “where permitted by the tables accompanying those figures” — if the table cell is shaded or the project falls outside the listed wind/snow/geometry limits you must use an alternative (proprietary connector design or engineered design). § R608.9.2 and § R608.9.3 require this.
Cold‑formed steel floor/roof provisions in R505 and R804 include applicability limits (e.g., 60 ft, 40 ft, 3 stories, Vult < 140 mph, ground snow ≤ 70 psf). If your project exceeds those limits, the code permits designing and constructing per AISI S230 or fully engineered design per AISI S100 / AISI S240.
For gypsum board support, minimum stud width of 1 1/4 inches is required for cold‑formed steel members per § R702.3.3; do not substitute narrower furring/track unless specifically allowed.

If a specific connection detail, fastener spacing or web‑hole condition is needed and the prescriptive figures don’t show it, the CRC directs you to the applicable AISI provision (AISI S230/S240/S100) or to follow R505/R804 tables and figures.

Common mistakes

Relying on AISI S220 for load‑bearing members. The code requires AISI S240 (load‑bearing) and AISI S220 is for nonload‑bearing framing. § R702.3.3 clarifies this distinction.
Using the prescriptive figures outside their applicability (ignoring shaded cells or wind/snow/geometry limits). § R608.9.2 and § R608.9.3 require an engineered solution in those cases.
Forgetting the minimum 1 1/4‑inch least dimension for cold‑formed steel that supports gypsum board. This is stated in § R702.3.3.
Omitting required corrosion/coating or identification requirements for load‑bearing members; R505 and R804 require compliance with AISI S240 for metallic coatings and product ID.

Worked example — applying the rule with numbers

Scenario: You are installing interior partitions and attaching gypsum board to cold‑formed steel studs for a single‑family house (not load‑bearing). The studs are 3 5/8 inches wide and the partition will not carry floor or roof loads.

Because the framing is nonload‑bearing, the CRC directs you to AISI S220 for nonload‑bearing cold‑formed steel framing. Also verify the studs meet the minimum 1 1/4‑inch least dimension for supporting gypsum per § R702.3.3.
Actionable steps: specify studs manufactured per AISI S220, confirm the stud web/flange dimensions meet the ≥ 1 1/4‑inch requirement and install gypsum per Table R702.3.5 attachments. If the partition becomes load‑bearing or must resist lateral loads, switch to AISI S240 and follow floor/roof/wall rules in R505/R804 or provide an engineered design per AISI S100.

Second scenario (connection): A cold‑formed‑steel floor assembly attaches to a concrete wall and basic wind speed and exposure fall into a table cell that is not shaded. The CRC allows use of the prescriptive Figure (e.g., Figures R608.9(5)–R608.9(8)) for cold‑formed steel floor to concrete connections where the accompanying table permits it; otherwise you must provide an engineered connection per § R608.9.2. Check the specific figure/table for required anchor bolt spacing and tension‑tie spacing.

Related provisions (quick list)

§ R702.3.3 — Cold‑formed steel framing for gypsum support (nonload vs load‑bearing; min width).
§ R608.9.2 — Connections between concrete walls and light‑frame floor systems (includes cold‑formed‑steel figures/tables).
§ R608.9.3 — Connections between concrete walls and light‑frame ceiling and roof systems (includes cold‑formed‑steel figures/tables).
§ R505.1.1 / R505 — Cold‑formed steel floor framing applicability limits and material/fastener requirements.
§ R804.1.1 / R804 — Cold‑formed steel roof framing applicability limits and material/fastener requirements.
§ R301.1.1 — Permits use of AISI S230 as an alternative prescriptive method for one‑ and two‑family dwellings (see referenced‑standards list).
Chapter 44 (Referenced Standards) — Lists AISI S100, S220, S230, S240 as the applicable AISI standards cited in the CRC.

Code references

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

CRC § 1.3 High relevance — show source text
332—20: Residential Code Requirements for Structural Concrete

R402.2, R403.1, R404.1.3, R404.1.3.4, R404.1.4.2, R506.1

AISI American Iron and Steel Institute 25 Massachusetts Avenue, NW Suite 800 Washington, DC 20001

AISI S100—16 (2020) w/S2—20: North American Specification for the Design of Cold-Formed Steel Structural Members, 2016 Edition (Reaffirmed 2020), with Supplement 2, 2020 Edition

R608.9.2, R608.9.3

AISI S220—20: North American Standard for Cold-Formed Steel Nonstructural Framing, 2020 Edition

R702.3.3

AISI S230—19: North American Standard for Cold-Formed Steel Framing—Prescriptive Method for One and Two Family Dwellings, 2019 Edition

R301.1.1, R301.2.1.1, R301.2.2.7, R301.2.2.8, R603.6, R603.9.4.1, R603.9.4.2, Figure R608.9(11), R608.9.2, R608.9.3, R608.10

AISI S240—20: North American Standard for Cold-Formed Steel Structural Framing, 2020 Edition

R505.1.3, R603.6, R702.3.3, R804.3.6

ALI Automotive Lift Institute, Inc. PO Box 85 Cortland, NY 13045

ALI ALCTV—2017: Standard for Automotive Lifts—Safety Requirements for Construction, Testing and Validation (ANSI)

R317.7

ANSI American National Standards Institute 25 West 43rd Street, 4th Floor New York, NY 10036

A108.1A—17: Installation of Ceramic Tile in the Wet-Set Method, with Portland Cement Mortar

R702.4.1

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REFERENCED STANDARDS

A108.1B—2017: Installation of Ceramic Tile on a Cured Portland Cement Mortar Setting Bed with Dry-Set or Latex Portland

Cement Mortar

R702.4.1

A108.4—19: Installation of Ceramic Tile with Organic Adhesives or Water-cleanable Tile-setting Epoxy Adhesive

R702.4.1

A108.5—21: Setting of Ceramic Tile with Dry-Set Cement Mortar, Modified Dry-Set Cement Mortar, EGP (Exterior Glue Plywood) Modified Dry-Set Cement Mortar, or Improved Modified Dry-Set Cement Mortar

R702.4.1

A108.6—99 (R2019): Installation of Ceramic Tile with Chemical Resistant, Water Cleanable Tile-Setting and -Grouting Epoxy

R702.4.1

A108.11—18: Interior Installation of Cementitious Backer Units

R702.4.1

A118.1—19: American National Standard Specifications for Dry-Set Portland Cement Mortar

R702.4.1
CRC § 722.5.2.2.1 High relevance — show source text
ANSI/AISC 360—22: Specification for Structural Steel Buildings 722.5.2.2.1, 1604.3.3, 1705.2.1, 1705A.2.1, Table 1705A.2.1, 1705A.2.5, 2201A.5.1, 2202.1, 2202.2.1.1, 2204.4, 2204A.4, 2215.1.1, 2215A.1.2, 2215A.2.1

ANSI/AISC 370—21: Specification for Structural Stainless Steel Buildings 1705.2.2, 1705.2.2, Table 1705A.2.1, 1705A.2.2, 2203.1

AISI American Iron and Steel Institute, 25 Massachusetts Avenue, NW Suite 800, Washington, DC 20001

AISI S100—16(2020) w/S2—20: North American Specification for the Design of Cold-Formed Steel Structural Members, 2016 Edition (Reaffirmed 2020), with Supplement 2, 2020 Edition

1604.3.3, 1905.7.2, 2204, 2204.2.2, 2204A.1

AISI S202—20: Code of Standard Practice for Cold-formed Steel Structural Framing, 2020 Edition

2206.1.3.1, 2206.1.3.1

AISI S220—20: North American Standard for Cold-Formed Steel Nonstructural Framing, 2020 Edition 2203.1, 2206.2, 2206.3, Table 2506.2, Table 2507.2

AISI S230—2019: North American Standard for Cold-formed Steel Framing—Prescriptive Method for One and Two Family Dwellings, 2019 Edition

1609.1.1, 1609.1.1.1, 2204.1, 2206.1.2

AISI S240—20: North American Standard for Cold-Formed Steel Structural Framing, 2020 Edition Table 1404.5.2.1, Table 1404.5.2.2, Table 1705A.2.1, 1709A.2.9, 2206.1, 2206.1.1.1, 2206.1.3.3, 2206.3, 2212.1, 2206A.2, Table 2506.2, Table 2507.2

AISI S310—20 w/S1—22: North American Standard for the Design of Profiled Steel Diaphragm Panels, with Supplement 1, 2022 Edition

2204.1, 2208.1

AISI S400—20: North American Standard for Seismic Design of Cold-formed Steel Structural Systems, 2020 Edition

2204.2.1, 2204.2.2, 2206.1.1.1, 2206.1.1.2 , 2215A.4.3

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REFERENCED STANDARDS
CRC § 44-2 High relevance — show source text
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Part IX— Referenced Standards

44 REFERENCED STANDARDS

Notwithstanding California laws and regulations, these referenced standards shall be applicable only to those California Residential Code sections that are adopted.

User notes:

About this chapter: The one- and two-family dwelling code contains numerous references to standards promulgated by other organizations that are used to provide requirements for materials, products and methods of construction. Chapter 44 contains a comprehensive list of all standards that are referenced in this code. These standards, in essence, are part of this code to the extent of the reference to the standard.

This chapter lists the standards that are referenced in various sections of this document. The standards are listed herein by the promulgating agency of the standard, the standard identification, the effective date and title, and the section or sections of this document that reference the standard. The application of the referenced standards shall be as specified in Section R102.4.

ABTG Applied Building Technology Group LLC6300 Enterprise Lane Madison, WI 53719

ANSI/ABTG FS 100—2012 (R2018): Standard Requirements for Wind Pressure Resistance of Foam Plastic Insulation Sheathing Used in Exterior Wall Covering Assemblies

R303.8

ACCA Air Conditioning Contractors of America 1330 Braddock Place, Suite 350 Alexandria, VA 22314

ANSI/ACCA 2 Manual J—2016: Residential Load Calculation

Table R301.2

ACI American Concrete Institute 38800 Country Club Drive Farmington Hills, MI 48331

318—19: Building Code Requirements for Structural Concrete R402.2, R404.1.3, R404.1.3.1, Table R404.1.3.2(2), Table R404.1.3.2(5), Table R404.1.3.2(6), Table R404.1.3.2(7), Table R404.1.3.2(8), R404.1.3.3, R404.1.3.4, R404.1.4.2, R404.5.1, R608.1, R608.1.1, R608.1.2, R608.2, R608.5.1, R608.6.1, R608.8.2, R608.9.2, R608.9.3

332—20: Residential Code Requirements for Structural Concrete

R402.2, R403.1, R404.1.3, R404.1.3.4, R404.1.4.2, R506.1

AISI American Iron and Steel Institute 25 Massachusetts Avenue, NW Suite 800 Washington, DC 20001

AISI S100—16 (2020) w/S2—20: North American Specification for the Design of Cold-Formed Steel Structural Members, 2016 Edition (Reaffirmed 2020), with Supplement 2, 2020 Edition

R608.9.2, R608.9.3

AISI S220—20: North American Standard for Cold-Formed Steel Nonstructural Framing, 2020 Edition

R702.3.3

AISI S230—19: North American Standard for Cold-Formed Steel Framing—Prescriptive Method for One and Two Family Dwellings, 2019 Edition
CRC § 0.42. High relevance — show source text
Portions of connections of wood-framed floor systems not noted in the figures shall be in accordance with Section R502, or AWC WFCM, if applicable. Wood framing members shall be of a species having a specific gravity equal to or greater than 0.42. 2. For floor systems of cold-formed steel construction, the provisions of Section R608.9.1 and the prescriptive details of Figures R608.9(5) through R608.9(8), where permitted by the tables accompanying those figures. Portions of connections of coldformed steel-framed floor systems not noted in the figures shall be in accordance with Section R505, or AISI S230, if applicable. 3. Proprietary connectors selected to resist loads and load combinations in accordance with Appendix A (ASD) or Appendix B (LRFD) of PCA 100. 4. An engineered design using loads and load combinations in accordance with Appendix A (ASD) or Appendix B (LRFD) of PCA 100.
1. An engineered design using loads and material design provisions in accordance with this code, or in accordance with ASCE 7, ACI 318, and AWC NDS for wood-framed construction or AISI S100 for cold-formed steel frame construction.
R608.9.3 Connections between concrete walls and light-frame ceiling and roof systems. Connections between concrete walls and light-frame ceiling and roof systems shall be in accordance with one of the following:
1. For ceiling and roof systems of wood-framed construction, the provisions of Section R608.9.1 and the prescriptive details of Figures R608.9(9) and R608.9(10), where permitted by the tables accompanying those figures. Portions of connections of wood-framed ceiling and roof systems not noted in the figures shall be in accordance with Section R802, or AWC WFCM, if applicable. Wood framing members shall be of a species having a specific gravity equal to or greater than 0.42.
2. For ceiling and roof systems of cold-formed steel construction, the provisions of Section R608.9.1 and the prescriptive details of Figures R608.9(11) and R608.9(12), where permitted by the tables accompanying those figures. Portions of
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connections of cold-formed steel-framed ceiling and roof systems not noted in the figures shall be in accordance with Section R804, or AISI S230, if applicable. 3. Proprietary connectors selected to resist loads and load combinations in accordance with Appendix A (ASD) or Appendix B (LRFD) of PCA 100. 4. An engineered design using loads and load combinations in accordance with Appendix A (ASD) or Appendix B (LRFD) of PCA 100.
1. An engineered design using loads and material design provisions in accordance with this code, or in accordance with ASCE 7, ACI 318, and AWC NDS for wood-framed construction or AISI S100 for cold-formed steel-framed construction.
CRC § 1609.1.1 High relevance — show source text
AISI S230—2019: North American Standard for Cold-formed Steel Framing—Prescriptive Method for One and Two Family Dwellings, 2019 Edition

1609.1.1, 1609.1.1.1, 2204.1, 2206.1.2

AISI S240—20: North American Standard for Cold-Formed Steel Structural Framing, 2020 Edition Table 1404.5.2.1, Table 1404.5.2.2, Table 1705A.2.1, 1709A.2.9, 2206.1, 2206.1.1.1, 2206.1.3.3, 2206.3, 2212.1, 2206A.2, Table 2506.2, Table 2507.2

AISI S310—20 w/S1—22: North American Standard for the Design of Profiled Steel Diaphragm Panels, with Supplement 1, 2022 Edition

2204.1, 2208.1

AISI S400—20: North American Standard for Seismic Design of Cold-formed Steel Structural Systems, 2020 Edition

2204.2.1, 2204.2.2, 2206.1.1.1, 2206.1.1.2 , 2215A.4.3

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ALI Automotive Lift Institute, Inc., P.O. Box 85, Cortland, NY 13045

ALI ALCTV—2022: Standard for Automotive Lifts—Safety Requirements for Construction, Testing and Validation (ANSI)

Table 3001.3

AMCA Air Movement and Control Association International, 30 West University Drive, Arlington Heights, IL 60004

ANSI/AMCA 540—23: Test Method for Louvers Impacted by Wind Borne Debris

1609.2.1

ANSI American National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036

A13.1—2020: Scheme for the Identification of Piping Systems

415.11.7.5

A108.1A—17: Installation of Ceramic Tile in the Wet-set Method, with Portland Cement Mortar

2103.2.3

A108.1B—17: Installation of Ceramic Tile on a Cured Portland Cement Mortar Setting Bed with Dry-set or Latex-Portland Cement

Mortar

2103.2.3

A108.4—19: Installation of Ceramic Tile with Organic Adhesives or Water-cleanable Tile-setting Epoxy Adhesive

2103.2.3.6

A108.5—21: Setting of Ceramic Tile with Dry-Set Cement Mortar, Modified Dry-Set Cement Mortar, EGP (Exterior Glue Plywood) Modified Dry-Set Cement Mortar, or Improved Modified Dry-Set Cement Mortar

2103.2.3.1, 2103.2.3.2

A108.6—99 (Reaffirmed 2019): Installation of Ceramic Tile with Chemical Resistant, Water Cleanable Tile-Setting and -Grouting Epoxy

2103.2.3.3
CRC § 1.1 High relevance — show source text
Existing buildings housing existing protective social care homes or facilities established prior to 1972 (see Chapter 11 of the California Fire Code and the California Existing Building Code).

R301.1.1 Alternative provisions. As an alternative to the requirements in Section R301.1, the following standards are permitted subject to the limitations of this code and the limitations therein. Where engineered design is used in conjunction with these standards, the design shall comply with the California Building Code .
1. AWC Wood Frame Construction Manual (WFCM).
2. AISI Standard for Cold-Formed Steel Framing—Prescriptive Method for One- and Two-Family Dwellings (AISI S230).
3. ICC Standard on the Design and Construction of Log Structures (ICC 400).
R301.1.1.1 Alternative provisions for limited-density owner-built rural dwellings. The purpose of this subsection is to permit alternatives that provide minimum protection of life, limb, health, property, safety and welfare of the general public and the owners and occupants of limited-density owner-built rural dwellings as defined in Chapter 2 of this code. For additional informa- tion see Chapter 1, Subchapter 1, Article 8, of Title 25, California Code of Regulations, commencing with Section 74.

To meet compliance with the requirements of this code, provisions of Section R301.1.1.1, Items 1 through 5 may be utilized for limited-density owner-built rural dwellings when the materials, methods of construction or appliances are determined appropri- ate or suitable for their intended purpose by the local enforcing agency. 1. A limited-density owner-built rural dwelling may be of any type of construction which will provide for a sound structural condition. Structural hazards which result in an unsound condition and which may constitute a substandard building are delineated in Section 17920.3 of the Health and Safety Code. 2. There shall be no requirements for room dimensions as required in Chapter 3, provided there is adequate light and venti- lation and means of egress. 3. There shall be no specified requirement for heating capacity or for temperature maintenance. The use of solid-fuel or solar heating devices shall be deemed as complying with the requirements of Chapter 3. If nonrenewable fuel is used in these dwellings, rooms so heated shall meet current installation standards. 4. Pier foundations, stone masonry footings and foundations, pressure-treated lumber, poles or equivalent foundation materials or designs may be used provided that bearing is sufficient. 5. Owner-produced or used materials and appliances may be utilized unless found not to be of sufficient strength or dura- bility to perform the intended function. Owner-produced or used lumber, or shakes and shingles may be utilized unless found to contain dry rot, excessive splitting or other defects obviously rendering the material unfit in strength or durabil- ity for the intended purpose.

R301.1.2 Construction systems. The requirements of this code are based on platform and balloon-frame construction for lightframe buildings. The requirements for concrete and masonry buildings are based on a balloon framing system. Other framing systems must have equivalent detailing to ensure force transfer, continuity and compatible deformations.

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CRC § 9.1 High relevance — show source text
For ceiling and roof systems of wood-framed construction, the provisions of Section R608.9.1 and the prescriptive details of Figures R608.9(9) and R608.9(10), where permitted by the tables accompanying those figures. Portions of connections of wood-framed ceiling and roof systems not noted in the figures shall be in accordance with Section R802, or AWC WFCM, if applicable. Wood framing members shall be of a species having a specific gravity equal to or greater than 0.42. 2. For ceiling and roof systems of cold-formed steel construction, the provisions of Section R608.9.1 and the prescriptive details of Figures R608.9(11) and R608.9(12), where permitted by the tables accompanying those figures. Portions of

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connections of cold-formed steel-framed ceiling and roof systems not noted in the figures shall be in accordance with Section R804, or AISI S230, if applicable. 3. Proprietary connectors selected to resist loads and load combinations in accordance with Appendix A (ASD) or Appendix B (LRFD) of PCA 100. 4. An engineered design using loads and load combinations in accordance with Appendix A (ASD) or Appendix B (LRFD) of PCA 100.
1. An engineered design using loads and material design provisions in accordance with this code, or in accordance with ASCE 7, ACI 318, and AWC NDS for wood-framed construction or AISI S100 for cold-formed steel-framed construction.
R608.10 Floor, roof and ceiling diaphragms. Floors and roofs in buildings with exterior walls of concrete shall be designed and constructed as diaphragms. Where gable-end walls occur, ceilings shall be designed and constructed as diaphragms. The design and construction of floors, roofs and ceilings of wood framing or cold-formed-steel framing serving as diaphragms shall comply with the applicable requirements of this code, or AWC WFCM or AISI S230, if applicable. Wood framing members shall be of a species having a specific gravity equal to or greater than 0.42.

SECTION R609—EXTERIOR WINDOWS AND DOORS

R609.1 General. This section prescribes performance and construction requirements for exterior windows, doors and garage doors installed in walls. Windows and doors shall be installed in accordance with the fenestration manufacturer’s written instructions. Window and door openings shall be flashed in accordance with Section R703.4. Written installation instructions shall be provided by the fenestration manufacturer for each window or door.

R609.2 Performance. Exterior windows and doors shall be capable of resisting the design wind loads specified in Table R301.2.1(1) adjusted for height and exposure in accordance with Table R301.2.1(2) or determined in accordance with ASCE 7 using the allowable stress design load combinations of ASCE 7. For exterior windows and doors tested in accordance with Sections R609.3 and R609.5, required design wind pressures determined from ASCE 7 using the ultimate strength design (USD) are permitted to be multiplied by 0.6. Design wind loads for exterior glazing not part of a labeled assembly shall be permitted to be determined in accordance with Chapter 24 of the California Building Code .
CRC § 2.1.1 High relevance — show source text
R301.2.1.1 Wind limitations and wind design required. The wind provisions of this code shall not apply to the design of buildings where wind design is required in accordance with Figure R301.2.1.1, or where the ultimate design wind speed, V ult, in Figure R301.2(2) equals or exceeds 140 miles per hour (225 kph) in a special wind region.

Exceptions:
1. For concrete construction, the wind provisions of this code shall apply in accordance with the limitations of Sections R404 and R608.
2. For structural insulated panels, the wind provisions of this code shall apply in accordance with the limitations of Section R610.
3. For cold-formed steel light-frame construction, the wind provisions of this code shall apply in accordance with the limitations of Sections R505, R603 and R804.
In regions where wind design is required in accordance with Figure R301.2.1.1 or where the ultimate design wind speed, V ult, in Figure R301.2(2) equals or exceeds 140 miles per hour (225 kph) in a special wind region, the design of buildings for wind loads shall be in accordance with one or more of the following methods:
1. AWC Wood Frame Construction Manual (WFCM).
2. ICC Standard for Residential Construction in High-Wind Regions (ICC 600).
3. ASCE Minimum Design Loads and Associated Criteria for Buildings and Other Structures (ASCE 7).
4. AISI Standard for Cold-Formed Steel Framing—Prescriptive Method for One- and Two-Family Dwellings (AISI S230).
5. California Building Code .
The elements of design not addressed by the methods in Items 1 through 5 shall be in accordance with the provisions of this code.

Where ASCE 7 or the California Building Code is used for the design of the building, the wind speed map and exposure category requirements as specified in ASCE 7 and the California Building Code shall be used.

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FIGURE R301.2.1.1—REGIONS WHERE WIND DESIGN IS REQUIRED

R301.2.1.1.1 Sunrooms. Sunrooms shall comply with AAMA/NPEA/NSA 2100. For the purpose of applying the criteria of AAMA/NPEA/NSA 2100 based on the intended use, sunrooms shall be identified as one of the following categories by the permit applicant, design professional or the property owner or owner’s agent in the construction documents. Component and cladding pressures shall be used for the design of elements that do not qualify as main windforce-resisting systems. Main windforce-resisting system pressures shall be used for the design of elements assigned to provide support and stability for the overall sunroom.

Category I: A thermally isolated sunroom with walls that are open or enclosed with insect screening or 0.5 mm (20 mil) maximum thickness plastic film. The space is nonhabitable and unconditioned.

Category II: A thermally isolated sunroom with enclosed walls. The openings are enclosed with translucent or transparent plastic or glass. The space is nonhabitable and unconditioned.

CRC § 3.1.1 High relevance — show source text

R702.3.1.1 Adhesives. Expandable foam adhesives for the installation of gypsum board and gypsum panel products shall conform to ASTM D6464. Other adhesives for the installation of gypsum board and gypsum panel products shall conform to ASTM C557. Supports and fasteners used to attach gypsum board and gypsum panel products shall comply with Table R702.3.5 or other approved method.

R702.3.2 Wood framing. Wood framing supporting gypsum board and gypsum panel products shall be not less than 2 inches (51 mm) nominal thickness in the least dimension except that wood furring strips not less than 1-inch by 2-inch (25 mm by 51 mm) nominal dimension shall be permitted to be used over solid backing or framing spaced not more than 24 inches (610 mm) on center.

R702.3.3 Cold-formed steel framing. Cold-formed steel framing supporting gypsum board and gypsum panel products shall be not less than 1 [1] / 4 inches (32 mm) wide in the least dimension. Nonload-bearing cold-formed steel framing shall comply with AISI S220. Load-bearing cold-formed steel framing shall comply with AISI S240.

R702.3.4 Insulating concrete form walls. Foam plastics for insulating concrete form walls constructed in accordance with Sections R404.1.2 and R608 on the interior of habitable spaces shall be protected in accordance with Section R303.4. Use of adhesives in conjunction with mechanical fasteners is permitted. Adhesives used for interior and exterior finishes shall be compatible with the insulating form materials.

R702.3.5 Application. Supports and fasteners used to attach gypsum board and gypsum panel products shall comply with Table R702.3.5. Gypsum sheathing shall be attached to exterior walls in accordance with Table R602.3(1). Gypsum board and gypsum panel products shall be applied at right angles or parallel to framing members. All edges and ends of gypsum board and gypsum panel products shall occur on the framing members, except those edges and ends that are perpendicular to the framing members. Interior gypsum board shall not be installed where it is directly exposed to the weather or to water.

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WALL COVERING

TABLE R702.3.5—MINIMUM THICKNESS AND APPLICATION OF GYPSUM BOARD AND GYPSUM PANEL PRODUCTS	Col2	Col3	Col4	Col5	Col6	Col7
THICKNESS OF GYPSUM BOARD OR GYPSUM PANEL PRODUCTS (inches)	APPLICATION	ORIENTATION OF GYPSUM BOARD OR GYPSUM PANEL PRODUCTS TO FRAMING	MAXIMUM SPACING OF FRAMING MEMBERS **(inches o.c.

CRC § 1.1 High relevance — show source text
SECTION 2205 A —COLD-FORMED STAINLESS STEEL

2205 A .1 General. The design of cold-formed stainless steel structural members shall be in accordance with ASCE 8.

SECTION 2206 A —COLD-FORMED STEEL LIGHT-FRAME CONSTRUCTION

2206 A .1 Structural framing. For cold-formed steel light-frame construction, the design and installation of the following structural framing systems, including their members and connections, shall be in accordance with AISI S240, and Sections 2206 A .1.1 through 2206 A .1.3, as applicable:
1. Floor and roof systems.
2. Structural walls.
3. Shear walls, strap-braced walls and diaphragms that resist in-plane lateral loads.
4. Trusses.
2206 A .1.1 Seismic requirements for cold-formed steel structural systems. The design of cold-formed steel light-frame construction to resist seismic forces shall be in accordance with the provisions of Section 2206 A .1.1.1 or 2206 A .1.1.2, as applicable.

2206 A .1.1.1 Seismic Design Categories B and C. Not permitted by DSA-SS and OSHPD.

2206 A .1.1.2 Seismic Design Categories D through F. In cold-formed steel light-frame construction assigned to Seismic Design Category D, E or F, the seismic force-resisting system shall be designed and detailed in accordance with AISI S400. The following additional requirements apply: 1. Cold-formed steel stud foundation plates or sills shall be bolted or fastened to the foundation or foundation wall in accordance with Section 2304.3.4, Item 2.

2. Shear wall assemblies in accordance with Sections E5, E6 and E7 of AISI 400 are not permitted within the seismic force- resisting system of buildings.

2206 A .1.2 Prescriptive framing. Not permitted by DSA-SS and OSHPD.

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STEEL

2206 A .1.3 Truss design. Cold-formed steel trusses shall comply with the additional provisions of Sections 2206 A .1.3.1. through 2206 A .1.3.3.

Complete engineering analysis and truss design drawings shall accompany the construction documents submitted to the enforce- ment agency for approval. When load testing is required, the test report shall be submitted with the truss design drawings and engineering analysis to the enforcement agency.
CRC § 7-4 High relevance — show source text
coat.

Exception: Applications installed in accordance with ASTM C926.

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WALL COVERING

R702.2.2.2 Curing. The finish coat for two-coat cement plaster shall not be applied sooner than 48 hours after application of the first coat. For three-coat cement plaster, the second coat shall not be applied sooner than 24 hours after application of the first coat. The finish coat for three-coat cement plaster shall not be applied sooner than 48 hours after application of the second coat.

R702.2.3 Support. Support spacing for gypsum or metal lath on walls or ceilings shall not exceed 16 inches (406 mm) for [3] / 8 -inchthick (9.5 mm) or 24 inches (610 mm) for [1] / 2 -inch-thick (12.7 mm) plain gypsum lath. Gypsum lath shall be installed at right angles to support framing with end joints in adjacent courses staggered by not less than one framing space.

R702.3 Gypsum board and gypsum panel products.

R702.3.1 Materials. Gypsum board and gypsum panel product materials and accessories shall conform to ASTM C22, C475, C514, C1002, C1047, C1177, C1178, C1278, C1396, C1658 or C1766 and shall be installed in accordance with the provisions of this section. Adhesives for the installation of gypsum board and gypsum panel products shall conform to ASTM C557.

R702.3.1.1 Adhesives. Expandable foam adhesives for the installation of gypsum board and gypsum panel products shall conform to ASTM D6464. Other adhesives for the installation of gypsum board and gypsum panel products shall conform to ASTM C557. Supports and fasteners used to attach gypsum board and gypsum panel products shall comply with Table R702.3.5 or other approved method.

R702.3.2 Wood framing. Wood framing supporting gypsum board and gypsum panel products shall be not less than 2 inches (51 mm) nominal thickness in the least dimension except that wood furring strips not less than 1-inch by 2-inch (25 mm by 51 mm) nominal dimension shall be permitted to be used over solid backing or framing spaced not more than 24 inches (610 mm) on center.

R702.3.3 Cold-formed steel framing. Cold-formed steel framing supporting gypsum board and gypsum panel products shall be not less than 1 [1] / 4 inches (32 mm) wide in the least dimension. Nonload-bearing cold-formed steel framing shall comply with AISI S220. Load-bearing cold-formed steel framing shall comply with AISI S240.

R702.3.4 Insulating concrete form walls. Foam plastics for insulating concrete form walls constructed in accordance with Sections R404.1.2 and R608 on the interior of habitable spaces shall be protected in accordance with Section R303.4. Use of adhesives in conjunction with mechanical fasteners is permitted. Adhesives used for interior and exterior finishes shall be compatible with the insulating form materials.
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.

Frequently asked questions

Does R702.3.3 allow using AISI S220 for load‑bearing walls?

No. § R702.3.3 requires AISI S220 for nonload‑bearing cold‑formed steel framing; load‑bearing cold‑formed steel framing must comply with AISI S240 (and design can follow AISI S100 if engineered).

When can I use AISI S230 (prescriptive method)?

You may use AISI S230 for prescriptive cold‑formed steel framing in one‑ and two‑family dwellings where the CRC permits the prescriptive details and where the project meets the figures’ tables and applicability limits (see § R301.1.1 and the referenced standards list).

If a table cell in Figures R608.9 is shaded, what then?

If the applicable figure/table does not permit the prescriptive detail (shaded or out of limits), § R608.9.2 and § R608.9.3 require either proprietary connectors sized per accepted methods or an engineered design (e.g., AISI S100/ASCE 7/ACI 318 as applicable).

What is the minimum stud width for attaching gypsum to cold‑formed steel?

§ R702.3.3 requires a minimum least dimension of 1 1/4 inches (32 mm) for cold‑formed steel framing that supports gypsum board or gypsum panel products.

Where do I find corrosion and identification requirements for load‑bearing members?

R505 and R804 require load‑bearing cold‑formed steel framing to meet material, coating and identification provisions of AISI S240 (see Sections R505.2.1–R505.2.4 and R804.2.1–R804.2.4).

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