CBC · California Building Code

What standards govern design, fabrication and erection of structural steel?

For a homeowner: The California Building Code says steel building members must be designed and built to the AISC 360 standard; if your building falls into certain seismic categories, the stricter AISC 341 earthquake detailing applies. The code also sets slenderness limits and agency‑specific rules you can check in §§ 2202 and 2202.1.

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Last reviewed: July 5, 2026

What the code requires

In California the baseline rule is simple: structural steel (and composite steel‑and‑concrete) used in buildings must be designed, fabricated and erected to the AISC Specification for Structural Steel Buildings (ANSI/AISC 360). That requirement is stated in § 2202.1 of the CBC. For seismic force‑resisting systems the CBC directs designers to AISC 341 (and related AISC provisions) where ASCE 7 or the seismic design category make that necessary — see § 2202 and the seismic subsections of Chapter 22 for those triggers.

Requirements in detail

Primary standard

  • The basic, nonseismic design, fabrication and erection standard for structural steel and composite steel‑concrete elements is AISC 360, as required by § 2202.1.

Seismic requirements and when AISC 341 applies

  • When the project’s seismic requirements make it necessary, the CBC requires the seismic design, detailing, fabrication and erection of structural steel seismic force‑resisting systems to follow AISC 341. The CBC distinguishes by Seismic Design Category and by the response modification coefficient (R) used under ASCE 7; see § 2202.2 and its subsections. In short:
    • Structures in Seismic Design Category D, E or F must be designed and detailed in accordance with AISC 341 (with limited exceptions listed in ASCE 7 Table 15.4‑1). Beam‑to‑column moment connections for special and intermediate moment frames must be prequalified or tested per the AISC provisions referenced in § 2202.2.1.2.
    • For structures in SD C or B, use of an R value from ASCE 7 may trigger AISC 341 detailing; an exception in § 2202.2.1.1 allows some non‑seismically detailed steel systems to remain under AISC 360 when a specific ASCE 7 R is used — read that exception carefully.

Fabrication, identification and connections

  • Identification of steel materials and conformity to required grades must follow the applicable referenced standards in Chapter 22; where marking or test records are insufficient, the CBC requires testing to verify conformity (§ 2201 and related notes). Connections and their installation are required to follow the referenced standards in this chapter; special inspection requirements for welding and high‑strength bolts are addressed elsewhere (see § 1705 cross‑references).

CBC amendments and agency modifications

  • The CBC includes modifications and agency‑specific amendments (DSA‑SS, OSHPD) to how AISC documents are applied — for example, mandatory fabricator marking of protected zones and limits on attachments into protected zones are set out as modifications to AISC 341/AISC 358 in Chapter 22A/22 (see the OSHPD/DSA notes and the 2202A/2202 modifications). These are binding where the agencies apply.

Key decision values and dimensions (quick reference table)

Item Value / Requirement Code reference
Baseline design/fabrication/erection standard ANSI/AISC 360 required for structural steel § 2202.1
Tension member slenderness limit (general exception) L/r ≤ 300 (except NFPA 13 hangers/rod hangers) § 2202.1 exceptions
Compression member slenderness limit (general exception) KL/r ≤ 200 (except NFPA 13 hangers/bracing) § 2202.1 exceptions
Seismic force‑resisting systems (SDC D/E/F) Design & detailing per AISC 341; SMF/IMF connections prequalified/tested per AISC 341 K1/K2 or AISC 358 § 2202.2.1.2
Structural steel elements in seismic systems (when R>3 or SDC D/E/F) Design per AISC 341 applies to struts, collectors, chords, foundation elements § 2202.2.2
Fabricator marking of protected zones (OSHPD/DSA) Fabricator must mark protected zones; re‑marking if obscured; primers for marking must meet § 704.13.3.2 2202A modifications (OSHPD/DSA)

Exceptions & special cases

  • Hangers and certain bracing designed under NFPA 13 are explicitly excepted from the slenderness limits in § 2202.1 (L/r and KL/r exceptions).
  • The CBC allows some steel systems not specifically detailed for seismic resistance to be designed under AISC 360 when the ASCE 7 Table 12.2‑1 R value designated for “Steel systems not specifically detailed for seismic resistance…” is used; see the exception in § 2202.2.1.1. That is a narrow allowance — don’t assume AISC 360 always suffices for seismic design.
  • State entity amendments (DSA‑SS, OSHPD) add additional rules and modifications to AISC documents (protected zones, weld pre/post‑heat, modifications to AISC 358 connection details). Where those agencies have jurisdiction, their amendments in Chapter 22A/22 apply; see the bracketed agency notes in § 2202 and the 2202A/2202 modifications.

Common mistakes

  • Assuming “design to AISC 360” always covers seismic detailing. For many seismic force‑resisting systems (SDC D/E/F or if using larger R values) the CBC requires AISC 341 detailing; misapplying AISC 360 can lead to noncompliance. § 2202.2 is the controlling text.
  • Forgetting the slenderness exceptions (or applying them where NFPA 13 does not apply). The L/r and KL/r limits in § 2202.1 are specific and limited.
  • Failing to observe agency modifications (OSHPD/DSA) such as marking protected zones or weld pre‑heat/post‑heat requirements; these are not optional where those agencies apply.
  • Overlooking special inspection triggers (welding and high‑strength bolts) — Chapter 17 special inspection cross‑references apply.

Worked example

Scenario: You are designing a single‑bay steel frame in an office building located in a seismic locality that assigns the structure to Seismic Design Category D. You have a short braced column and a long tension rod in a nonseismic brace.

  1. Standards to apply

    • Because the building is SDC D, the CBC requires design and detailing per AISC 341 for the seismic force‑resisting system (beam‑to‑column connections, etc.). § 2202.2.1.2 requires AISC 341 for SDC D, E or F.

  2. Check slenderness for a compression column

    • Column gross length (unbraced length) L = 12 ft = 144 in.
    • Radius of gyration r = 0.8 in.
    • Use K = 1.0 (pinned ends), then KL/r = 1.0 × 144 / 0.8 = 180.
    • Compare with CBC limit: KL/r must not exceed 200 per § 2202.1 exception (unless NFPA 13 hanger exception applies). 180 ≤ 200 → OK. § 2202.1.

  3. Check slenderness for a tension rod

    • Rod length L = 20 ft = 240 in.
    • Radius of gyration r = 1.0 in.
    • L/r = 240 / 1 = 240.
    • Compare with CBC limit: L/r ≤ 300 per § 2202.1 exceptions (unless NFPA 13 hanger exception applies). 240 ≤ 300 → OK.

  4. Connection prequalification

    • Since the frame is a moment‑resisting seismic force‑resisting system in SDC D, beam‑to‑column moment connections must be prequalified/tested as described in AISC 341 (K1/K2) or be prequalified under AISC 358 where permitted; follow CBC § 2202.2.1.2 instructions.

Result: Use AISC 341 for design and detailing; the two member slenderness checks pass the CBC limits. Document in the construction documents which AISC edition and which AISC 341 prequalification/testing route you used, and arrange for the required special inspections.

Related provisions

  • § 2201 — General chapter scope, identification, protection and connections (cross‑references to Chapter 17 special inspection).
  • § 2202.2 / § 2202.2.1.1 / § 2202.2.1.2 — Seismic design triggers and AISC 341 requirements (SDC‑specific).
  • 2202A / 2202.3 / 2202.4 — Agency (OSHPD/DSA) modifications to AISC provisions (protected zones, attachments, AISC 358 adjustments).
  • § 2208 — Steel deck minimum base thickness and related referenced standards (see Chapter 22 deck provisions).
  • § 2210 — Metal building systems referencing § 2202 for structural steel.
  • § 1705 — Special inspection requirements for welding and high‑strength bolts (referenced from Chapter 22).

Code references

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

  • CBC § 2201A.5.1 High relevance — show source text

    2201 A .5 Anchor rods. Anchor rods shall be set in accordance with the approved construction documents. The protrusion of the threaded ends through the connected material shall fully engage the threads of the nuts, but shall not be greater than the length of the threaded portion of the bolts. 2201A.5.1 Shear transfer at column base plate. Where the holes in column base plates are more than [1] / 8 inch (3 mm) larger than the anchor rods, as permitted by AISC 360, the anchor rods shall be designed for the induced bending stresses in combination with axial and shear stresses. Alternatively, shear lugs designed in accordance with ACI 318 Section 17.11 shall be permitted to transfer shear forces between column base plates and the supporting structure.

    SECTION 2202 A —STRUCTURAL STEEL AND COMPOSITE STRUCTURAL STEEL AND CONCRETE

    2202 A .1 General. The design, fabrication and erection of structural steel elements and composite structural steel and concrete elements in buildings, structures and portions thereof shall be in accordance with AISC 360.

    Exceptions : [OSHPD 1 & 4]

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    1. For members designed based on tension, the slenderness ratio (L/r) shall not exceed 300, except for the design of hangers and bracing in accordance with NFPA 13 and for rod hangers in tension. 2. For members designed based on compression, the slenderness ratio (KL/r) shall not exceed 200, except for the design of hangers and bracing in accordance with NFPA 13.

    2202 A .2 Seismic design. Where required, the seismic design, fabrication and erection of buildings, structures and portions thereof shall be in accordance with Section 2202 A .2.1 or 2202 A .2.2, as applicable.

    2202 A .2.1 Structural steel seismic force-resisting systems and composite structural steel and concrete seismic force- resisting systems. The design, detailing, fabrication and erection of structural steel seismic force-resisting systems and composite structural steel and concrete seismic force-resisting systems shall be in accordance with the provisions of Section 2202 A .2.1.1 or 2202 A .2.1.2, as applicable. Seismic force-resisting systems of structural steel acting compositely with reinforced concrete shall be considered as an alternative system, except as permitted by:

    [DSA-SS] Section 2202A.6.1.

    [OSHPD 1 & 4] Section 2202A.4.1.

    2202 A .2.1.1 Seismic Design Category B or C. Not permitted by DSA-SS and OSHPD.

  • CBC § 15.5.3 High relevance — show source text

    2209 A .2 Seismic design. Where required by ASCE 7, the seismic design of steel storage racks and cantilevered steel storage racks shall be in accordance with Section 15.5.3 of ASCE 7.

    2209 A .3 Certification. For steel storage racks that are 8 feet (2438 mm) in height or greater to the top load level and assigned to Seismic Design Category D, E, or F at completion of the storage rack installation, a certificate of compliance shall be submitted to the owner or the owner’s authorized agent stating that the work was performed in accordance with approved construction documents.

    SECTION 2210 A —METAL BUILDING SYSTEMS

    2210 A .1 General. The design, fabrication and erection of a metal building system shall be in accordance with the provisions of this section.

    2210 A .1.1 Design. The design of metal building systems shall be in accordance with Sections 2210 A .1.1.1 through 2210 A .1.1.4, as applicable.

    2210 A .1.1.1 Structural steel. The design, fabrication and erection of structural steel shall be in accordance with Section 2202 A .

    2210 A .1.1.2 Cold-formed steel. The design of cold-formed carbon and low-alloy steel structural members shall be in accordance with Section 2204 A .

    2210 A .1.1.3 Steel joists. The design of steel joists shall be in accordance with Section 2207 A .

    2210 A .1.1.4 Steel cable. The design, fabrication and erection of steel cables, including related connections, shall be in accordance with Section 2214 A .

    2210 A .2 Seismic design. Where required, the seismic design, fabrication and erection of the structural steel seismic force-resisting system shall be in accordance with Section 2202 A .2.1 or 2202 A .2.2, as applicable.

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    SECTION 2211 A —INDUSTRIAL BOLTLESS STEEL SHELVING

    2211 A .1 General. The design, testing and utilization of industrial boltless steel shelving shall be in accordance with MHI ANSI/MH 28.2. Where required by ASCE 7, the seismic design of industrial boltless steel shelving shall be in accordance with Chapter 15 of ASCE 7.

    SECTION 2212 A —INDUSTRIAL STEEL WORK PLATFORMS

    2212 A .1 General. The design, testing and utilization of industrial steel work platforms shall be in accordance with MHI ANSI/MH 28.3. Where required by ASCE 7, the seismic design of industrial steel work platforms shall be in accordance with Chapter 15 of ASCE 7.

  • CBC § 2206.2 High relevance — show source text

    3|||||||||||X|X|||X|||||||||| |2206.2|||||||||||X|X|||X|||||||||| |2215|||||||||X|||||||||||||||| |2216|||||||||||X|X|||X||||||||||

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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    22 STEEL

    User notes:

    About this chapter: Chapter 22 provides the minimum requirements for the design and construction of structural steel (including composite construction), cold-formed steel, steel joists, steel cable structures and steel storage racks. This chapter specifies appropriate design and construction standards for these types of structures. It also provides a road map of the applicable technical requirements for steel structures. Chapter 22 requires that the design and use of steel structures and components be in accordance with the applicable specifications and standards of the American Institute of Steel Construction, the American Iron and Steel Institute, the Steel Joist Institute and the American Society of Civil Engineers.

    This chapter was extensively reorganized for the 2024 edition. For complete information, see the relocations table in the Preface information of this code.

    ICC code development note: Code change proposals to this chapter will be considered by the IBC—Structural Code Development Committee during the

    2025 (Group B) Code Development Cycle.

    SECTION 2201—GENERAL

    2201.1 Scope. The provisions of this chapter govern the quality, design, fabrication and erection of steel construction.

    2201.1.1 Application. [DSA-SS/CC, OSHPD] The scope of application of Chapter 22 is as follows: 1. Structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD), which include hospital buildings removed from general acute care service, skilled nursing facility buildings, intermediate care facility buildings and acute psychiatric hospital buildings, as listed in Sections 1.10.1, 1.10.2 and 1.10.5.

    2. Structures regulated by the Division of the State Architect-Structural Safety/Community Colleges (DSA-SS/CC), which include those applications listed in Section 1.9.2.2.

    2201.1.2 Amendments in this chapter. [DSA-SS/CC, OSHPD] DSA-SS/CC, OSHPD adopt this chapter as amended.

    2201.1.3 Identification of amendments. [DSA-SS/CC, OSHPD] 1. [OSHPD 1R, 2 & 5] Office of Statewide Hospital Planning and Development (OSHPD) amendments appear in this chapter preceded by the appropriate acronym, as follows:

    [OSHPD 1R ] - For applications listed in Section 1.10.1.

    [OSHPD 2] - For applications listed in Section 1.10.2.

  • CBC § 1704.5 High relevance — show source text

    2207 A .5 Certification. At completion of manufacture, the steel joist manufacturer shall submit a certificate of compliance to the owner or the owner’s authorized agent for submittal to the building official as specified in Section 1704.5 stating that work was performed in accordance with approved construction documents and with SJI 100 or SJI 200, as applicable.

    2207A.6 Joist chord bracing. The chords of all joists shall be laterally supported at all points where the chords change direction.

    SECTION 2208 A —STEEL DECK

    2208 A .1 Steel decks. The design and construction of cold-formed steel floor and roof decks and composite slabs of concrete and steel deck shall be in accordance with SDI SD. The design of cold-formed steel diaphragms shall be in accordance with additional provisions of AISI S310, as applicable. The base material thickness of steel deck shall not be less than 0.0359 inch (0.9 mm) (20 gage).

    Exception: [DSA-SS] For single-story open structures, the minimum deck thickness may be waived if the steel roof deck need not be used as the diaphragm and there are no suspended hangers or bracing for nonstructural components attached to the deck.

    SECTION 2209 A —STEEL STORAGE RACKS

    2209 A .1 General. The design, testing and utilization of steel storage racks made of cold-formed or hot-rolled steel structural members shall be in accordance with ANSI MH16.1. The design, testing and utilization of steel cantilevered storage racks made of cold-formed or hot-rolled steel structural members shall be in accordance with ANSI MH 16.3.

    2209 A .2 Seismic design. Where required by ASCE 7, the seismic design of steel storage racks and cantilevered steel storage racks shall be in accordance with Section 15.5.3 of ASCE 7.

    2209 A .3 Certification. For steel storage racks that are 8 feet (2438 mm) in height or greater to the top load level and assigned to Seismic Design Category D, E, or F at completion of the storage rack installation, a certificate of compliance shall be submitted to the owner or the owner’s authorized agent stating that the work was performed in accordance with approved construction documents.

    SECTION 2210 A —METAL BUILDING SYSTEMS

    2210 A .1 General. The design, fabrication and erection of a metal building system shall be in accordance with the provisions of this section.

    2210 A .1.1 Design. The design of metal building systems shall be in accordance with Sections 2210 A .1.1.1 through 2210 A .1.1.4, as applicable.

    2210 A .1.1.1 Structural steel. The design, fabrication and erection of structural steel shall be in accordance with Section 2202 A .

    2210 A .1.1.2 Cold-formed steel. The design of cold-formed carbon and low-alloy steel structural members shall be in accordance with Section 2204 A .

  • CBC § 2.1 High relevance — show source text

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    1. For members designed based on tension, the slenderness ratio (L/r) shall not exceed 300, except for the design of hangers and bracing in accordance with NFPA 13 and for rod hangers in tension. 2. For members designed based on compression, the slenderness ratio (KL/r) shall not exceed 200, except for the design of hangers and bracing in accordance with NFPA 13.

    2202 A .2 Seismic design. Where required, the seismic design, fabrication and erection of buildings, structures and portions thereof shall be in accordance with Section 2202 A .2.1 or 2202 A .2.2, as applicable.

    2202 A .2.1 Structural steel seismic force-resisting systems and composite structural steel and concrete seismic force- resisting systems. The design, detailing, fabrication and erection of structural steel seismic force-resisting systems and composite structural steel and concrete seismic force-resisting systems shall be in accordance with the provisions of Section 2202 A .2.1.1 or 2202 A .2.1.2, as applicable. Seismic force-resisting systems of structural steel acting compositely with reinforced concrete shall be considered as an alternative system, except as permitted by:

    [DSA-SS] Section 2202A.6.1.

    [OSHPD 1 & 4] Section 2202A.4.1.

    2202 A .2.1.1 Seismic Design Category B or C. Not permitted by DSA-SS and OSHPD.

    2202 A .2.1.2 Seismic Design Category D, E or F. Structures assigned to Seismic Design Category D, E or F shall be designed and detailed in accordance with AISC 341. Beam-to-column moment connections in structural steel special moment frames and intermediate moment frames shall be prequalified in accordance with AISC 341, Section K1, qualified by testing in accordance with AISC 341, Section K2, or shall be prequalified in accordance with AISC 358.

    2202 A .2.2 Structural steel elements. The design, detailing, fabrication and erection of structural steel elements in seismic forceresisting systems, including struts, collectors, chords and foundation elements, shall be in accordance with AISC 341.

    2202A.3 Modifications to AISC 341. [OSHPD 1 and 4]

    2202A.3.1 Section A4. Modify Section A4.1 Item (c) by adding the following:

    (c) Locations and dimensions of protected zones. The fabricator shall permanently mark protected zones of structural elements in the seismic force-resisting system in the building that are designated on the construction documents. If these markings are obscured during construction, such as after the application of fire protection, the owner’s designated representative shall re-mark the protected zones as they are designated on the construction documents. [OSHPD 1 & 4] Primers or paints used to mark protected zones on steel surfaces, which are to receive sprayed fire-resistance material, shall comply with California Building Code Section 704.13.3.2.

  • CBC § 2201.5 High relevance — show source text

    2201.5 Anchor rods. Anchor rods shall be set in accordance with the approved construction documents. The protrusion of the threaded ends through the connected material shall fully engage the threads of the nuts, but shall not be greater than the length of the threaded portion of the bolts.

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    2201.5.1 Shear transfer at column base plate. [OSHPD 1R, 2 & 5] Where the holes in column base plates are more than [1] / 8 inch (3 mm) larger than the anchor rods, as permitted by AISC 360, the anchor rods shall be designed for the induced bending stresses in combination with axial and shear stresses. Alternatively, shear lugs designed in accordance with ACI 318 Section 17.11 shall be permitted to transfer shear forces between column base plates and the supporting structure.

    SECTION 2202—STRUCTURAL STEEL AND COMPOSITE STRUCTURAL STEEL AND CONCRETE

    2202.1 General. The design, fabrication and erection of structural steel elements and composite structural steel and concrete elements in buildings, structures and portions thereof shall be in accordance with AISC 360.

    Exceptions : [OSHPD 1R, 2 & 5] 1. For members designed based on tension, the slenderness ratio (L/r) shall not exceed 300, except for the design of hangers and bracing in accordance with NFPA 13 and for rod hangers in tension. 2. For members designed based on compression, the slenderness ratio (KL/r) shall not exceed 200, except for the design of hangers and bracing in accordance with NFPA 13.

    2202.2 Seismic design. Where required, the seismic design, fabrication and erection of buildings, structures and portions thereof shall be in accordance with Section 2202.2.1 or 2202.2.2, as applicable.

    2202.2.1 Structural steel seismic force-resisting systems and composite structural steel and concrete seismic force-resist- ing systems. The design, detailing, fabrication and erection of structural steel seismic force-resisting systems and composite structural steel and concrete seismic force-resisting systems shall be in accordance with the provisions of Section 2202.2.1.1 or 2202.2.1.2, as applicable.

    [ OSHPD 1R, 2 & 5 ] Seismic requirements for composite structural steel and concrete construction shall be considered as an alter- native system, except as permitted by Section 2202.4.1.

    2202.2.1.1 Seismic Design Category B or C. Structures assigned to Seismic Design Category B or C shall be of any construction permitted in Section 2202. Where a response modification coefficient, R, in accordance with ASCE 7, Table 12.2-1, is used for the design of structures assigned to Seismic Design Category B or C, the structures shall be designed and detailed in accordance with the requirements of AISC 341. Beam-to-column moment connections in structural steel special moment frames and intermediate moment frames shall be prequalified in accordance with AISC 341, Section K1, qualified by testing in accordance with AISC 341, Section K2, or shall be prequalified in accordance with AISC 358.

  • CBC § 2.1.2 High relevance — show source text

    2202 A .2.1.2 Seismic Design Category D, E or F. Structures assigned to Seismic Design Category D, E or F shall be designed and detailed in accordance with AISC 341. Beam-to-column moment connections in structural steel special moment frames and intermediate moment frames shall be prequalified in accordance with AISC 341, Section K1, qualified by testing in accordance with AISC 341, Section K2, or shall be prequalified in accordance with AISC 358.

    2202 A .2.2 Structural steel elements. The design, detailing, fabrication and erection of structural steel elements in seismic forceresisting systems, including struts, collectors, chords and foundation elements, shall be in accordance with AISC 341.

    2202A.3 Modifications to AISC 341. [OSHPD 1 and 4]

    2202A.3.1 Section A4. Modify Section A4.1 Item (c) by adding the following:

    (c) Locations and dimensions of protected zones. The fabricator shall permanently mark protected zones of structural elements in the seismic force-resisting system in the building that are designated on the construction documents. If these markings are obscured during construction, such as after the application of fire protection, the owner’s designated representative shall re-mark the protected zones as they are designated on the construction documents. [OSHPD 1 & 4] Primers or paints used to mark protected zones on steel surfaces, which are to receive sprayed fire-resistance material, shall comply with California Building Code Section 704.13.3.2.

    2202A.3.2 Section I2. [OSHPD 1 & 4] Replace Section I2.1 Item (d) as follows:

    (d) Decking attachments that penetrate the beam flange shall not be placed on beam flanges within the protected zone, except power-actuated fasteners up to 0.18 inch in diameter are permitted, provided that the penetration is less than 85 percent of beam flange thickness.

    2202A.4 Modifications to AISC 358. [OSHPD 1 and 4]

    2202A.4.1 Modifications to AISC 358 Chapter 10. [OSHPD 1 and 4] Steel and concrete ConXtech ConXL composite special moment frame connections shall be permitted, provided: 1. Beams are provided with reduced beam sections (RBS); 2. Web extension to beam web two-sided fillet welds are sized to develop expected strength of the beam web and shall not be less than a [1] / 4 inch fillet weld; and 3. The built-up box column wall thickness shall not be less than 1.25 inches and the HSS column wall thickness shall not be less than [1] / 2 inch.

    2202A.4.2 Modifications to AISC 358 Chapter 11 Welded Moment Connection. The welded side plate steel moment connection shall be permitted, provided: 1. The beams shall consist of either rolled or built-up wide flange sections. 2. The biaxial dual-strong axis and column minor axis configurations of the moment connection shall be considered as an alternative system. 3. For SMF and IMF systems, U-shaped cover plates shall be used and the hinge-to-hinge span to beam depth, L h _/d,

  • CBC § 2210.1.1.1 High relevance — show source text

    2210.1.1.1 Structural steel. The design, fabrication and erection of structural steel shall be in accordance with Section 2202.

    2210.1.1.2 Cold-formed steel. The design of cold-formed carbon and low-alloy steel structural members shall be in accordance with Section 2204.

    2210.1.1.3 Steel joists. The design of steel joists shall be in accordance with Section 2207.

    2210.1.1.4 Steel cable. The design, fabrication and erection of steel cables, including related connections, shall be in accordance with Section 2214.

    2210.2 Seismic design. Where required, the seismic design, fabrication and erection of the structural steel seismic force-resisting system shall be in accordance with Section 2202.2.1 or 2202.2.2, as applicable.

    SECTION 2211—INDUSTRIAL BOLTLESS STEEL SHELVING

    2211.1 General. The design, testing and utilization of industrial boltless steel shelving shall be in accordance with MHI ANSI/MH 28.2. Where required by ASCE 7, the seismic design of industrial boltless steel shelving shall be in accordance with Chapter 15 of ASCE 7.

    SECTION 2212—INDUSTRIAL STEEL WORK PLATFORMS

    2212.1 General. The design, testing and utilization of industrial steel work platforms shall be in accordance with MHI ANSI/MH 28.3. Where required by ASCE 7, the seismic design of industrial steel work platforms shall be in accordance with Chapter 15 of ASCE 7.

    SECTION 2213—STAIRS, LADDERS AND GUARDING FOR STEEL STORAGE RACKS AND INDUSTRIAL STEEL WORK PLATFORMS

    2213.1 General. The design and installation of stairs, ladders and guarding serving steel storage racks and industrial steel work platforms shall be in accordance with MHI ANSI/MH 32.1.

    SECTION 2214—STEEL CABLE STRUCTURES

    2214.1 General. The design, fabrication and erection including related connections, and protective coatings of steel cables for buildings shall be in accordance with ASCE 19.

    [OSHPD 1R, 2 & 5] Steel cables with glass or polymer fabric material acting as a tensile membrane structure shall be considered as an alternative system.

    SECTION 2215 — ADDITIONAL REQUIREMENTS FOR COMMUNITY COLLEGES [DSA-SS/CC]

    2215.1 General.

    2215.1.1 Shear transfer at column base plate. Where the holes in column base plates are more than [1] / 8 inch (3 mm) larger than the anchor rods, as permitted by AISC 360, the anchor rods shall be designed for the induced bending stresses in combination with axial and shear stresses. Alternatively, shear lugs designed in accordance with ACI 318 Section 17.11 shall be permitted to transfer shear forces between column base plates and the supporting structure.

    2215.2 Modifications to AISC 341.

    2215.2.1 Section B5. Modify exception of Section B5.2(a) as follows:

  • CBC § 2202.2.1.2 High relevance — show source text

    2202.2.1.2 Seismic Design Category D, E or F. Structures assigned to Seismic Design Category D, E or F shall be designed and detailed in accordance with AISC 341, except as permitted in ASCE 7, Table 15.4-1. Beam-to-column moment connections in structural steel special moment frames and intermediate moment frames shall be prequalified in accordance with AISC 341, Section K1, qualified by testing in accordance with AISC 341, Section K2, or shall be prequalified in accordance with AISC 358.

    [OSHPD 1R, 2 & 5] All structural steel seismic force-resisting systems in ASCE 7 Table 15.4-1 shall be designed in accordance with AISC 341.

    2202.2.2 Structural steel elements. The design, detailing, fabrication and erection of structural steel elements in seismic forceresisting systems other than those covered in Section 2202.2.1, including struts, collectors, chords and foundation elements, shall be in accordance with AISC 341 where either of the following applies:

    1. The structure is assigned to Seismic Design Category D, E or F, except as permitted in ASCE 7, Table 15.4-1.
    2. A response modification coefficient, R, greater than 3 in accordance with ASCE 7, Table 12.2-1, is used for the design of the structure assigned to Seismic Design Category B or C.

    [OSHPD 1R, 2 & 5] All structural steel elements in seismic force-resisting systems shall satisfy the requirements in AISC 341.

    2202.3 Modifications to AISC 341. [OSHPD 1R, 2 & 5]

    2202.3.1 Section A4. Modify Section A4.1 Item (c) by adding the following:

    (c) Locations and dimensions of protected zones. The fabricator shall permanently mark protected zones of structural elements in the seismic force-resisting system in the building that are designated on the construction documents. If these markings are obscured during construction, such as after the application of fire protection, the owner’s designated representative shall re-mark the protected zones as they are designated on the construction documents. Primers or paints used to mark protected zones on steel surfaces, which are to receive sprayed fire-resistance material, shall comply with California Building Code Section 704.13.3.2.

    2202.3.2 Section I2. Replace Section I2.1 item (d) as follows:

    (d) Decking attachments that penetrate the beam flange shall not be placed on beam flanges within the protected zone, except power-actuated fasteners up to 0.18 in. diameter are permitted, provided that the penetration is less than 85% of beam flange thickness.

    2202.4 Modifications to AISC 358. [OSHPD 1R, 2 & 5]

    2202.4.1 Modifications to AISC 358 Chapter 10. Steel and concrete ConXtech ConXL composite special moment frame connections shall be permitted, provided: a. Beams are provided with Reduced Beam Sections (RBS);

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  • CBC § 2209.1 High relevance — show source text

    Exception: For single-story, nonbuilding structures similar to buildings, the minimum deck thickness need not apply if the steel roof deck is not being used as the diaphragm and there are no suspended hangers or bracing for nonstructural components attached to the deck.

    SECTION 2209—STEEL STORAGE RACKS

    2209.1 General. The design, testing and utilization of steel storage racks made of cold-formed or hot-rolled steel structural members shall be in accordance with ANSI MH16.1. The design, testing and utilization of steel cantilevered storage racks made of cold-formed or hot-rolled steel structural members shall be in accordance with ANSI MH 16.3.

    2209.2 Seismic design. Where required by ASCE 7, the seismic design of steel storage racks and cantilevered steel storage racks shall be in accordance with Section 15.5.3 of ASCE 7.

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    2209.3 Certification. For steel storage racks that are 8 feet (2438 mm) in height or greater to the top load level and assigned to Seismic Design Category D, E, or F at completion of the storage rack installation, a certificate of compliance shall be submitted to the owner or the owner’s authorized agent stating that the work was performed in accordance with approved construction documents.

    SECTION 2210—METAL BUILDING SYSTEMS

    2210.1 General. The design, fabrication and erection of a metal building system shall be in accordance with the provisions of this section.

    2210.1.1 Design. The design of metal building systems shall be in accordance with Sections 2210.1.1.1 through 2210.1.1.4, as applicable.

    2210.1.1.1 Structural steel. The design, fabrication and erection of structural steel shall be in accordance with Section 2202.

    2210.1.1.2 Cold-formed steel. The design of cold-formed carbon and low-alloy steel structural members shall be in accordance with Section 2204.

    2210.1.1.3 Steel joists. The design of steel joists shall be in accordance with Section 2207.

    2210.1.1.4 Steel cable. The design, fabrication and erection of steel cables, including related connections, shall be in accordance with Section 2214.

    2210.2 Seismic design. Where required, the seismic design, fabrication and erection of the structural steel seismic force-resisting system shall be in accordance with Section 2202.2.1 or 2202.2.2, as applicable.

    SECTION 2211—INDUSTRIAL BOLTLESS STEEL SHELVING

    2211.1 General. The design, testing and utilization of industrial boltless steel shelving shall be in accordance with MHI ANSI/MH 28.2. Where required by ASCE 7, the seismic design of industrial boltless steel shelving shall be in accordance with Chapter 15 of ASCE 7.

    SECTION 2212—INDUSTRIAL STEEL WORK PLATFORMS

    2212.1 General. The design, testing and utilization of industrial steel work platforms shall be in accordance with MHI ANSI/MH 28.3. Where required by ASCE 7, the seismic design of industrial steel work platforms shall be in accordance with Chapter 15 of ASCE 7.

  • CBC § 2201A.1.1 High relevance — show source text

    SECTION 2201 A —GENERAL

    2201 A .1 Scope. The provisions of this chapter govern the quality, design, fabrication and erection of steel construction.

    2201A.1.1 Application. The scope of application of Chapter 22A is as follows: 1. Structures regulated by the Division of the State Architect-Structural Safety (DSA-SS), which include those applications listed in Section 1.9.2.1. These applications include public elementary and secondary schools, community colleges and state- owned or state-leased essential services buildings. 2. Structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD), which include those applications listed in Sections 1.10.1 and 1.10.4. These applications include hospitals and correctional treatment centers.

    2201A.1.2 Amendments in this chapter. DSA-SS and OSHPD adopt this chapter and all amendments.

    Exception: Amendments adopted by only one agency appear in this chapter preceded with the appropriate acronym of the adopt- ing agency, as follows: 1. Division of the State Architect-Structural Safety: [DSA-SS] For applications listed in Section 1.9.2.1. 2. Office of Statewide Hospital Planning and Development:

    [OSHPD 1] - For applications listed in Section 1.10.1.

    [OSHPD 4] - For applications listed in Section 1.10.4.

    2201 A .2 Identification. Identification of steel members shall be in accordance with the applicable referenced standards within this chapter. Other steel furnished for structural load-carrying purposes shall be identified for conformity to the ordered grade in accordance with the specified ASTM standard or other specification and the provisions of this chapter. Where the steel grade is not readily identifiable from marking and test records, the steel shall be tested to verify conformity to such standards. [DSA-SS] All material iden- tification and testing shall be in accordance with Chapter 17A.

    2201 A .3 Protection. The protection of steel members shall be in accordance with the applicable referenced standards within this chapter.

    2201 A .4 Connections. The design and installation of steel connections shall be in accordance with the applicable referenced standards within this chapter. For special inspection of welding or installation of high-strength bolts, see Section 1705 A .2.

    2201A.4.1 Restrained welded connections. [OSHPD 1 & 4] Welded structural steel connections having a medium or high level of restraint, as defined by AWS D1.1 Annex H, shall have a minimum pre-heat temperature of not less than 150 [o] F (66 [o] C). Welded struc- tural steel connections with welds to flange, web, wall or plate having a high level of restraint shall maintain a post-heat temperature of 300 [o] F (149 [o] C) for a minimum of 1 hour after completion of welding.

  • CBC § 2202.2 High relevance — show source text

    2202.2 Seismic design. Where required, the seismic design, fabrication and erection of buildings, structures and portions thereof shall be in accordance with Section 2202.2.1 or 2202.2.2, as applicable.

    2202.2.1 Structural steel seismic force-resisting systems and composite structural steel and concrete seismic force-resist- ing systems. The design, detailing, fabrication and erection of structural steel seismic force-resisting systems and composite structural steel and concrete seismic force-resisting systems shall be in accordance with the provisions of Section 2202.2.1.1 or 2202.2.1.2, as applicable.

    [ OSHPD 1R, 2 & 5 ] Seismic requirements for composite structural steel and concrete construction shall be considered as an alter- native system, except as permitted by Section 2202.4.1.

    2202.2.1.1 Seismic Design Category B or C. Structures assigned to Seismic Design Category B or C shall be of any construction permitted in Section 2202. Where a response modification coefficient, R, in accordance with ASCE 7, Table 12.2-1, is used for the design of structures assigned to Seismic Design Category B or C, the structures shall be designed and detailed in accordance with the requirements of AISC 341. Beam-to-column moment connections in structural steel special moment frames and intermediate moment frames shall be prequalified in accordance with AISC 341, Section K1, qualified by testing in accordance with AISC 341, Section K2, or shall be prequalified in accordance with AISC 358.

    Exception: The response modification coefficient, R, designated for “Steel systems not specifically detailed for seismic resistance, excluding cantilever column systems” in ASCE 7, Table 12.2-1, shall be permitted for structural steel systems designed and detailed in accordance with AISC 360, and need not be designed and detailed in accordance with AISC 341.

    2202.2.1.2 Seismic Design Category D, E or F. Structures assigned to Seismic Design Category D, E or F shall be designed and detailed in accordance with AISC 341, except as permitted in ASCE 7, Table 15.4-1. Beam-to-column moment connections in structural steel special moment frames and intermediate moment frames shall be prequalified in accordance with AISC 341, Section K1, qualified by testing in accordance with AISC 341, Section K2, or shall be prequalified in accordance with AISC 358.

    [OSHPD 1R, 2 & 5] All structural steel seismic force-resisting systems in ASCE 7 Table 15.4-1 shall be designed in accordance with AISC 341.

    2202.2.2 Structural steel elements. The design, detailing, fabrication and erection of structural steel elements in seismic forceresisting systems other than those covered in Section 2202.2.1, including struts, collectors, chords and foundation elements, shall be in accordance with AISC 341 where either of the following applies:

    1. The structure is assigned to Seismic Design Category D, E or F, except as permitted in ASCE 7, Table 15.4-1.
    2. A response modification coefficient, R, greater than 3 in accordance with ASCE 7, Table 12.2-1, is used for the design of the structure assigned to Seismic Design Category B or C.

Frequently asked questions

What is the single controlling standard for nonseismic steel design in the CBC?

The CBC mandates design, fabrication and erection of structural steel to ANSI/AISC 360 under § 2202.1.

When do I have to use AISC 341 instead of AISC 360?

When seismic design requirements make AISC 341 applicable — for example most systems in Seismic Design Categories D, E or F and specific cases where ASCE 7 or R values trigger it — see § 2202.2 and subsections.

Are there slenderness limits in the CBC I must check?

Yes. § 2202.1 includes exceptions that cap tension member slenderness at L/r ≤ 300 and compression member slenderness at KL/r ≤ 200 (with limited NFPA 13 exceptions).

Do state agencies (DSA/OSHPD) change these rules?

Yes. DSA and OSHPD adopt chapter amendments (marked in the code) that modify application of AISC standards (protected zones, welding pre/post‑heat, AISC 358 modifications) where those agencies have jurisdiction; check the agency notes in Chapter 22/22A.

Are special inspections required for steel welding and bolts?

Special inspection provisions for welding and high‑strength bolts are handled via Chapter 17 cross‑references; Chapter 22 directs you to those inspection requirements.

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