CBC · California Building Code

What special inspections are required for seismic force‑resisting systems and seismic steel?

If your building uses steel for the seismic lateral system (SDC B–F), the CBC generally requires special inspections following AISC 341; the designer must list which seismic systems need inspection, certain low‑hazard or specifically detailed systems may be excepted, and required inspection reports and certificates must be submitted to the building official.

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

The CBC requires special inspections of structural steel that is part of seismic force‑resisting systems in buildings assigned to Seismic Design Categories B, C, D, E or F, and those inspections must follow the quality‑assurance requirements of AISC 341 unless an exception applies (see § 1705.13.1.1 and § 1705.13.1.2) . The project’s Statement of Special Inspections must identify the designated seismic systems and components subject to those inspections as required by § 1704.3.2 . Nondestructive testing requirements for the same systems are addressed separately in § 1705.14.1 and also point to AISC 341 where applicable .

Requirements in detail

Scope — which steel is covered

  • Structural steel in seismic force‑resisting systems for SDC B–F must be inspected in accordance with AISC 341 quality‑assurance provisions (special inspection) — § 1705.13.1.1 .
  • Structural steel elements in the seismic force‑resisting system not covered by § 1705.13.1.1 (for example: struts, collectors, chords, foundation elements) must also be inspected per AISC 341 — § 1705.13.1.2 .

Where the CBC allows exceptions (high‑level)

  • For some SDC B or C projects and certain “non‑seismically detailed” steel systems the CBC removes the AISC 341 special‑inspection requirement when specific ASCE 7 R‑values/design rules are used — see the CBC exceptions to § 1705.13.1.1 .
  • For SDC D, E or F, if ASCE 7 permits design and detailing per AISC 360 instead of AISC 341 (ASCE 7 Table 15.4‑1), the special‑inspection requirement may not apply — see exception text to § 1705.13.1.1 and § 1705.13.1.2 .
  • The CBC also sets broader exceptions where the entire set of seismic special inspections in § 1705.13 are not required (low SDS and low building height, or ordinary detached one‑ and two‑family dwellings without specified irregularities) — § 1705.13 exceptions .

Statement of special inspections and submittals

  • The Statement of Special Inspections must identify the designated seismic systems and seismic force‑resisting systems that require the special inspections or tests (this is mandatory when § 1705.13 or § 1705.14 apply) — § 1704.3.2 .
  • Certificates, mill reports and final special‑inspection reports required by the CBC must be submitted to the building official as described in § 1704.5 and related sections (see references) .

Decision table — when special inspection required (quick reference)

Seismic Design Category (SDC) Element / Condition Inspection required? Code Reference
B or C Structural steel in seismic force‑resisting systems (generally) Yes — AISC 341 quality‑assurance special inspections, unless the design used the ASCE 7 R for “Steel systems not specifically detailed for seismic resistance” noted in the CBC exception § 1705.13.1.1
B or C Structural steel elements with R ≤ 3 (per CBC exception) Exception — special inspection not required for elements when R ≤ 3 § 1705.13.1.2
D, E or F Structural steel in seismic force‑resisting systems Yes — AISC 341 special inspections, unless ASCE 7 permits AISC 360 detailing for that system (see ASCE 7 Table 15.4‑1) § 1705.13.1.1 and exceptions
D, E or F Struts, collectors, chords, foundation steel elements Yes — AISC 341 quality‑assurance inspection required (unless exception per CBC applies) § 1705.13.1.2
Any SDC Project qualifying under the § 1705.13 global exceptions (low SDS / low height / small detached dwelling w/o irregularities) No — the seismic special inspections in § 1705.13 are not required § 1705.13 exceptions

(Use ASCE 7 tables referenced in the CBC to confirm whether a particular steel system is treated as “detailed for seismic resistance” or may be designed under AISC 360 — the CBC exceptions point back to those ASCE 7 tables) .

Extent and type of inspection

  • The CBC delegates the inspection scope to the AISC 341 quality‑assurance requirements (which define tasks, welding inspection, nondestructive testing, etc.) — CBC requires compliance with AISC 341 for the items above (§ 1705.13.1.1 and § 1705.13.1.2) .
  • Nondestructive testing for structural steel in seismic force‑resisting systems likewise follows AISC 341 when required by the CBC (§ 1705.14.1.1 and § 1705.14.1.2) .

Exceptions & special cases

  • R‑value / system‑type exceptions (ASCE 7 cross‑references): In SDC B or C, if the designer uses the ASCE 7 R for “steel systems not specifically detailed for seismic resistance” the CBC removes the special‑inspection requirement for seismic force‑resisting steel in some cases — see the CBC exception to § 1705.13.1.1 .
  • Alternate detailing (AISC 360) for SDC D–F: Where ASCE 7 allows AISC 360 detailing rather than AISC 341, the CBC’s special‑inspection requirement for AISC 341 may not apply; instead the referenced standard in ASCE 7 governs — see CBC exception language to § 1705.13.1.1 and § 1705.13.1.2 .
  • Small/low‑hazard buildings: The CBC’s § 1705.13 contains broader exceptions (low SDS / short building / small detached dwellings without irregularities) that exempt the seismic special inspections entirely for qualifying projects — § 1705.13 exceptions .
  • Jurisdictional limits: Some enforcement agencies or special programs (OSHPD, DSA) restrict or modify the use of certain AISC 341 Chapter J quality‑assurance provisions — the CBC acknowledges these agency notes in the advisory language (see the California amendments) .

Common mistakes

  • Treating “structural steel” as only main columns and beams; collectors, struts, chords and foundation steel that are part of the seismic system are explicitly included and must be addressed as required by § 1705.13.1.2 .
  • Failing to identify the designated seismic systems in the Statement of Special Inspections — § 1704.3.2 requires those systems and components to be listed when § 1705.13 applies .
  • Assuming AISC 341 always applies without checking the CBC exceptions tied to ASCE 7 (R‑values and AISC 360 permissibility) — those exceptions are explicit in § 1705.13.1.1/1.2 .
  • Not submitting required certificates, mill reports, or final inspection reports to the building official as required by CBC submittal rules (see § 1704.5) .
  • Overlooking nondestructive testing requirements: NDT scope for seismic steel is addressed in § 1705.14.1 and may invoke AISC 341 NDT provisions where applicable .

Worked example — 6‑story office building, Seismic Design Category D

Scenario: A new 6‑story office building in SDC D uses steel special moment frames (SMF) as part of the lateral system. SMF are seismic moment‑resisting frames that are specifically detailed for seismic resistance and are treated in ASCE 7/AISC 341 as a seismically detailed system.

Stepwise application:

  1. Because the building is SDC D and the lateral system is an SMF, the CBC requires special inspections in accordance with AISC 341 for the structural steel in the seismic force‑resisting system — see § 1705.13.1.1 .
  2. The project’s Statement of Special Inspections must list the SMF and associated elements (beam‑column connections, welds, NDT tasks, etc.) per § 1704.3.2 .
  3. The special inspector’s scope (as delegated by the CBC) follows the AISC 341 quality‑assurance tasks: welding inspection, NDT where required, fabrication and erection checks. Any nondestructive testing required for SMF welds follows § 1705.14.1.1 (AISC 341 guidance) .
  4. Submit mill reports, certificates of compliance and final special‑inspection reports to the building official per § 1704.5 .
    Result: Continuous/periodic special inspection and specified NDT are required and must be documented and reported in accordance with AISC 341 and the CBC sections cited above.

Related provisions (CBC)

  • Statement of special inspections — § 1704.3.2
  • Submittals and certificates of compliance — § 1704.5
  • General seismic special‑inspection scope and exceptions — § 1705.13 (general)
  • Nondestructive testing for seismic steel — § 1705.14.1 and subsections
  • Special inspection content for structural steel and referenced AISC standards — § 1705A.2.1 and § 1705A.13.1/13.1.1 (California amendments discuss application limits)

Code references

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

  • CBC § 1613.2.4 High relevance — show source text

    The structure consists of light-frame construction; the design spectral response acceleration at short periods, S DS, as determined in Section 1613.2.4, does not exceed 0.5; and the building height of the structure does not exceed 35 feet (10 668 mm). 2. The seismic force-resisting system of the structure consists of reinforced masonry or reinforced concrete; the design spectral response acceleration at short periods, S DS, as determined in Section 1613.2.4, does not exceed 0.5; and the building height of the structure does not exceed 25 feet (7620 mm). 3. The structure is a detached one- or two-family dwelling not exceeding two stories above grade plane and does not have any of the following horizontal or vertical irregularities in accordance with Section 12.3 of ASCE 7: 3.1. Torsional or extreme torsional irregularity. 3.2. Nonparallel systems irregularity. 3.3. Stiffness-soft story or stiffness-extreme soft story irregularity. 3.4. Discontinuity in lateral strength-weak story irregularity.

    1705.13.1 Structural steel. Special inspections for seismic resistance shall be in accordance with Section 1705.13.1.1 or 1705.13.1.2, as applicable.

    1705.13.1.1 Seismic force-resisting systems. Special inspections of structural steel in the seismic force-resisting systems in buildings and structures assigned to Seismic Design Category B, C, D, E or F shall be performed in accordance with the quality assurance requirements of AISC 341. [OSHPD 1R, 2 & 5] and this code.

    Exceptions: [OSHPD 1R, 2 & 5] Not permitted by OSHPD.

    1. In buildings and structures assigned to Seismic Design Category B or C, special inspections are not required for structural steel seismic force-resisting systems where 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, has been used for design and detailing.

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    1. In structures assigned to Seismic Design Category D, E, or F, special inspections are not required for structural steel seismic force-resisting systems where design and detailing in accordance with AISC 360 is permitted by ASCE 7, Table 15.4-1.

    1705.13.1.2 Structural steel elements. Special inspections of structural steel elements in the seismic force-resisting systems of buildings and structures assigned to Seismic Design Category B, C, D, E or F other than those covered in Section 1705.13.1.1, including struts, collectors, chords and foundation elements, shall be performed in accordance with the quality assurance requirements of AISC 341. [OSHPD 1R, 2 & 5] and this code.

  • CBC § 1705A.2.1 High relevance — show source text

    Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    1705 A .13.1.2 Structural steel elements. Special inspections of structural steel elements in the seismic force-resisting systems of buildings and structures assigned to Seismic Design Category D, E or F other than those covered in Section 1705 A .13.1.1, including struts, collectors, chords and foundation elements, shall be performed in accordance with the quality assurance requirements of AISC 341 and this code .

    [DSA-SS, DSA-SS/CC] Quality assurance application is not permitted for the following AISC 341, Chapter J Sections: 1. J6 (Inspection Tasks). 2. J7 (Welding Inspection and Nondestructive Testing). 3. J10 (Inspection of Composite Structures). 4. J11 (Inspection of H-Piles).

    Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    1705 A .13.2 Structural wood. For the seismic force-resisting systems of structures assigned to Seismic Design Category D, E or F:

    1. Continuous special inspection shall be required during field gluing operations of elements of the seismic force-resisting system.
    2. Periodic special inspection shall be required for nailing, bolting, anchoring and other fastening of elements of the seismic force-resisting system, including wood shear walls, wood diaphragms, drag struts, braces, shear panels and hold-downs.

    1705 A .13.3 Cold-formed steel light-frame construction. For the seismic force-resisting systems of structures assigned to Seismic Design Category D, E or F, periodic special inspection shall be required for both:

    1. Welding operations of elements of the seismic force-resisting system.
    2. Screw attachment, bolting, anchoring and other fastening of elements of the seismic force-resisting system, including shear walls, braces, diaphragms, collectors (drag struts) and hold-downs.

    [DSA-SS, DSA-SS/CC] Requirements specified in Section 1705A.2.9 shall also apply.

    1705 A .13.4 Special inspection for special seismic certification . For structures assigned to Seismic Design Category D, E or F, the special inspector shall examine equipment and components requiring special seismic certification in accordance with Section 1705A.14.3 or ASCE 7 , Section 13.2.3 and verify that the label, anchorage and mounting conform to the certificate of compliance.

    1705 A .13.5 Architectural components. Periodic special inspection is required for the erection and fastening of exterior cladding, interior and exterior nonbearing walls, ceilings and interior and exterior veneer in structures assigned to Seismic Design Category D, E or F.

    [OSHPD 1] E x ception: Periodic special inspection is not required where continuous inspection of the work is performed in accor- dance with Section 7-145 of the CAC .

    1705 A .13.5.1 Access floors. Periodic special inspection is required for the anchorage of access floors in structures assigned to Seismic Design Category D, E or F.

  • CBC § 12.3 High relevance — show source text

    1705 A .12.3 Wind-resisting components. Periodic special inspection is required for fastening of the following systems and components:

    1. Roof covering, roof deck and roof framing connections.
    2. Exterior wall covering and wall connections to roof and floor diaphragms and framing.

    1705 A .13 Special inspections for seismic resistance. Special inspections for seismic resistance shall be required as specified in Sections 1705 A .13.1 through 1705 A .13.9, unless exempted by the exceptions of Section 1704 A .2.

    1705 A .13.1 Structural steel. Special inspections for seismic resistance shall be in accordance with Section 1705 A .13.1.1 or 1705 A .13.1.2, as applicable.

    1705 A .13.1.1 Seismic force-resisting systems. Special inspections of structural steel in the seismic force-resisting systems in buildings and structures assigned to Seismic Design Category D, E or F shall be performed in accordance with the quality assurance requirements of AISC 341 and this code.

    [DSA-SS, DSA-SS/CC] Quality assurance application is not permitted for the following AISC 341, Chapter J Sections: 1. J6 (Inspection Tasks).

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    2. J7 (Welding Inspection and Nondestructive Testing). 3. J10 (Inspection of Composite Structures). 4. J11 (Inspection of H-Piles).

    Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    1705 A .13.1.2 Structural steel elements. Special inspections of structural steel elements in the seismic force-resisting systems of buildings and structures assigned to Seismic Design Category D, E or F other than those covered in Section 1705 A .13.1.1, including struts, collectors, chords and foundation elements, shall be performed in accordance with the quality assurance requirements of AISC 341 and this code .

    [DSA-SS, DSA-SS/CC] Quality assurance application is not permitted for the following AISC 341, Chapter J Sections: 1. J6 (Inspection Tasks). 2. J7 (Welding Inspection and Nondestructive Testing). 3. J10 (Inspection of Composite Structures). 4. J11 (Inspection of H-Piles).

    Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    1705 A .13.2 Structural wood. For the seismic force-resisting systems of structures assigned to Seismic Design Category D, E or F:

    1. Continuous special inspection shall be required during field gluing operations of elements of the seismic force-resisting system.
    2. Periodic special inspection shall be required for nailing, bolting, anchoring and other fastening of elements of the seismic force-resisting system, including wood shear walls, wood diaphragms, drag struts, braces, shear panels and hold-downs.
  • CBC § 1705.13.7 High relevance — show source text
    TABLE 1705.13.7—REQUIRED INSPECTIONS OF STORAGE RACK SYSTEMS Col2 Col3 Col4 Col5
    TYPE CONTINUOUS
    INSPECTION    		 PERIODIC
    INSPECTION    		 REFERENCED
    STANDARD    		 IBC REFERENCE
    1. Materials used, to verify compliance with one or more of the
    material test reports in accordance with the approved
    construction documents.    		 — X — —
    2. Fabricated storage rack elements. — X — Section 1704.2.5
    3. Storage rack anchorage installation. — X ANSI/MH16.1
    Section 7.3.2    		 —
    4. Completed storage rack system, to indicate compliance with
    the approved construction documents.    		 — X — —

    1705.13.8 Seismic isolation systems. Periodic special inspection shall be provided for seismic isolation systems in seismically isolated structures assigned to Seismic Design Category B, C, D, E or F during the fabrication and installation of isolator units and energy dissipation devices.

    1705.13.9 Cold-formed steel special bolted moment frames. Periodic special inspection shall be provided for the installation of cold-formed steel special bolted moment frames in the seismic force-resisting systems of structures assigned to Seismic Design Category D, E or F.

    1705.14 Testing for seismic resistance. Testing for seismic resistance shall be required as specified in Sections 1705.14.1 through 1705.14.4, unless exempted from special inspections by the exceptions of Section 1704.2.

    1705.14.1 Structural steel. Nondestructive testing for seismic resistance shall be in accordance with Section 1705.14.1.1 or 1705.14.1.2, as applicable.

    1705.14.1.1 Seismic force-resisting systems. Nondestructive testing of structural steel in the seismic force-resisting systems in buildings and structures assigned to Seismic Design Category B, C, D, E or F shall be performed in accordance with the quality assurance requirements of AISC 341. [OSHPD 1R, 2 & 5] and this code.

    Exceptions: [OSHPD 1R, 2 & 5] Not permitted by OSHPD.

    1. In buildings and structures assigned to Seismic Design Category B or C, nondestructive testing is not required for structural steel seismic force-resisting systems where 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, has been used for design and detailing.
    2. In structures assigned to Seismic Design Category D, E, or F, nondestructive testing is not required for structural steel seismic force-resisting systems where design and detailing in accordance with AISC 360 is permitted by ASCE 7, Table 15.4-1.
  • CBC § 1705.12.2 High relevance — show source text

    1705.12.2 Cold-formed steel light-frame construction. Periodic special inspection is required for welding operations of elements of the main windforce-resisting system. Periodic special inspection is required for screw attachment, bolting, anchoring and other fastening of elements of the main windforce-resisting system, including shear walls, braces, diaphragms, collectors (drag struts) and hold-downs.

    Exception: Special inspections are not required for cold-formed steel light-frame shear walls and diaphragms, including screwing, bolting, anchoring and other fastening to components of the windforce-resisting system, where either of the following applies:

    1. The sheathing is gypsum board or fiberboard.
    2. The sheathing is wood structural panel or steel sheets on only one side of the shear wall, shear panel or diaphragm assembly and the specified fastener spacing at the panel or sheet edges is more than 4 inches (102 mm) on center (o.c.).

    1705.12.3 Wind-resisting components. Periodic special inspection is required for fastening of the following systems and components:

    1. Roof covering, roof deck and roof framing connections.
    2. Exterior wall covering and wall connections to roof and floor diaphragms and framing.

    1705.13 Special inspections for seismic resistance. Special inspections for seismic resistance shall be required as specified in Sections 1705.13.1 through 1705.13.9, unless exempted by the exceptions of Section 1704.2.

    Exception: The special inspections specified in Sections 1705.13.1 through 1705.13.9 are not required for structures designed and constructed in accordance with one of the following:

    1. The structure consists of light-frame construction; the design spectral response acceleration at short periods, S DS, as determined in Section 1613.2.4, does not exceed 0.5; and the building height of the structure does not exceed 35 feet (10 668 mm).
    2. The seismic force-resisting system of the structure consists of reinforced masonry or reinforced concrete; the design spectral response acceleration at short periods, S DS, as determined in Section 1613.2.4, does not exceed 0.5; and the building height of the structure does not exceed 25 feet (7620 mm).
    3. The structure is a detached one- or two-family dwelling not exceeding two stories above grade plane and does not have any of the following horizontal or vertical irregularities in accordance with Section 12.3 of ASCE 7: 3.1. Torsional or extreme torsional irregularity. 3.2. Nonparallel systems irregularity. 3.3. Stiffness-soft story or stiffness-extreme soft story irregularity. 3.4. Discontinuity in lateral strength-weak story irregularity.

    1705.13.1 Structural steel. Special inspections for seismic resistance shall be in accordance with Section 1705.13.1.1 or 1705.13.1.2, as applicable.

    1705.13.1.1 Seismic force-resisting systems. Special inspections of structural steel in the seismic force-resisting systems in buildings and structures assigned to Seismic Design Category B, C, D, E or F shall be performed in accordance with the quality assurance requirements of AISC 341. [OSHPD 1R, 2 & 5] and this code.

  • CBC § 12.2 High relevance — show source text

    Exceptions: [OSHPD 1R, 2 & 5] Not permitted by OSHPD.

    1. In buildings and structures assigned to Seismic Design Category B or C, special inspections are not required for structural steel seismic force-resisting systems where 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, has been used for design and detailing.

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    1. In structures assigned to Seismic Design Category D, E, or F, special inspections are not required for structural steel seismic force-resisting systems where design and detailing in accordance with AISC 360 is permitted by ASCE 7, Table 15.4-1.

    1705.13.1.2 Structural steel elements. Special inspections of structural steel elements in the seismic force-resisting systems of buildings and structures assigned to Seismic Design Category B, C, D, E or F other than those covered in Section 1705.13.1.1, including struts, collectors, chords and foundation elements, shall be performed in accordance with the quality assurance requirements of AISC 341. [OSHPD 1R, 2 & 5] and this code.

    Exceptions: [OSHPD 1R, 2 & 5] Not permitted by OSHPD.

    1. In buildings and structures assigned to Seismic Design Category B or C, special inspections of structural steel elements are not required for seismic force-resisting systems with a response modification coefficient, R, of 3 or less.
    2. In structures assigned to Seismic Design Category D, E, or F, special inspections of structural steel elements are not required for seismic force-resisting systems where design and detailing other than AISC 341 is permitted by ASCE 7, Table 15.4-1. Special inspection shall be in accordance with the applicable referenced standard listed in ASCE 7, Table 15.4-1.

    1705.13.2 Structural wood. For the seismic force-resisting systems of structures assigned to Seismic Design Category C, D, E or F:

    1. Continuous special inspection shall be required during field gluing operations of elements of the seismic force-resisting system.
    2. Periodic special inspection shall be required for nailing, bolting, anchoring and other fastening of elements of the seismic force-resisting system, including wood shear walls, wood diaphragms, drag struts, braces, shear panels and hold-downs.

    Exception: Special inspections are not required for wood shear walls, shear panels and diaphragms, including nailing, bolting, anchoring and other fastening to other elements of the seismic force-resisting system, where the lateral resistance is provided by structural sheathing, and the specified fastener spacing at the panel edges is more than 4 inches (102 mm) on center.

    1705.13.3 Cold-formed steel light-frame construction. For the seismic force-resisting systems of structures assigned to Seismic Design Category C, D, E or F, periodic special inspection shall be required for both:

    1. Welding operations of elements of the seismic force-resisting system.
    2. Screw attachment, bolting, anchoring and other fastening of elements of the seismic force-resisting system, including shear walls, braces, diaphragms, collectors (drag struts) and hold-downs.
  • CBC § 1705.14 High relevance — show source text

    1705.14 Testing for seismic resistance. Testing for seismic resistance shall be required as specified in Sections 1705.14.1 through 1705.14.4, unless exempted from special inspections by the exceptions of Section 1704.2.

    1705.14.1 Structural steel. Nondestructive testing for seismic resistance shall be in accordance with Section 1705.14.1.1 or 1705.14.1.2, as applicable.

    1705.14.1.1 Seismic force-resisting systems. Nondestructive testing of structural steel in the seismic force-resisting systems in buildings and structures assigned to Seismic Design Category B, C, D, E or F shall be performed in accordance with the quality assurance requirements of AISC 341. [OSHPD 1R, 2 & 5] and this code.

    Exceptions: [OSHPD 1R, 2 & 5] Not permitted by OSHPD.

    1. In buildings and structures assigned to Seismic Design Category B or C, nondestructive testing is not required for structural steel seismic force-resisting systems where 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, has been used for design and detailing.
    2. In structures assigned to Seismic Design Category D, E, or F, nondestructive testing is not required for structural steel seismic force-resisting systems where design and detailing in accordance with AISC 360 is permitted by ASCE 7, Table 15.4-1.

    1705.14.1.2 Structural steel elements. Nondestructive testing of structural steel elements in the seismic force-resisting systems of buildings and structures assigned to Seismic Design Category B, C, D, E or F other than those covered in Section 1705.14.1.1, including struts, collectors, chords and foundation elements, shall be performed in accordance with the quality assurance requirements of AISC 341. [OSHPD 1R, 2 & 5] and this code.

    Exceptions: [OSHPD 1R, 2 & 5] Not permitted by OSHPD.

    1. In buildings and structures assigned to Seismic Design Category B or C, nondestructive testing of structural steel elements is not required for seismic force-resisting systems with a response modification coefficient, R, of 3 or less.
    2. In structures assigned to Seismic Design Category D, E or F, nondestructive testing of structural steel elements is not required for seismic force-resisting systems where design and detailing other than AISC 341 is permitted by ASCE 7, Table 15.4-1. Nondestructive testing of structural steel elements shall be in accordance with the applicable referenced standard listed in ASCE 7, Table 15.4-1.

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  • CBC § 2.5. High relevance — show source text

    1705 A .10 Structural integrity of deep foundation elements. Whenever there is a reasonable doubt as to the structural integrity of a deep foundation element, an engineering assessment shall be required. The engineering assessment shall include tests for defects performed in accordance with ASTM D4945, ASTM D5882, ASTM D6760 or ASTM D7949, or other approved method.

    1705 A .11 Fabricated items. Special inspections of fabricated items shall be performed in accordance with Section 1704 A .2.5.

    1705 A .12 Special inspections for wind resistance. Special inspections for wind resistance specified in Sections 1705 A .12.1 through 1705 A .12.3, unless exempted by the exceptions to Section 1704 A .2, are required for buildings and structures constructed in the following areas:

    1. In wind Exposure Category B, where basic wind speed, V, is 150 mph (67 m/sec) or greater.
    2. In wind Exposure Category C or D, where basic wind speed, V, is 140 mph (62.6 m/sec) or greater.

    1705 A .12.1 Structural wood. Continuous special inspection is required during field gluing operations of elements of the main windforce-resisting system. Periodic special inspection is required for nailing, bolting, anchoring and other fastening of elements of the main windforce-resisting system, including wood shear walls, wood diaphragms, drag struts, braces and hold-downs.

    1705 A .12.2 Cold-formed steel light-frame construction. Periodic special inspection is required for welding operations of elements of the main windforce-resisting system. Periodic special inspection is required for screw attachment, bolting, anchoring and other fastening of elements of the main windforce-resisting system, including shear walls, braces, diaphragms, collectors (drag struts) and hold-downs. [DSA-SS, DSA-SS/CC] Requirements specified in Section 1705A.2.9 shall also apply.

    1705 A .12.3 Wind-resisting components. Periodic special inspection is required for fastening of the following systems and components:

    1. Roof covering, roof deck and roof framing connections.
    2. Exterior wall covering and wall connections to roof and floor diaphragms and framing.

    1705 A .13 Special inspections for seismic resistance. Special inspections for seismic resistance shall be required as specified in Sections 1705 A .13.1 through 1705 A .13.9, unless exempted by the exceptions of Section 1704 A .2.

    1705 A .13.1 Structural steel. Special inspections for seismic resistance shall be in accordance with Section 1705 A .13.1.1 or 1705 A .13.1.2, as applicable.

    1705 A .13.1.1 Seismic force-resisting systems. Special inspections of structural steel in the seismic force-resisting systems in buildings and structures assigned to Seismic Design Category D, E or F shall be performed in accordance with the quality assurance requirements of AISC 341 and this code.

  • CBC § 17-5 High relevance — show source text

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

    SPECIAL INSPECTIONS AND TESTS

    1704.3.2 Seismic requirements in the statement of special inspections. Where Section 1705.13 or 1705.14 specifies special inspections or tests for seismic resistance, the statement of special inspections shall identify the designated seismic systems and seismic force-resisting systems that are subject to the special inspections or tests. [OSHPD 1R, 2 & 5] Where Section 1705.13 or 1705.14 specifies special inspections or tests for seismic resistance, the statement of special inspections shall identify the equip- ment/components that require special seismic certification and seismic force-resisting systems that are subject to the special inspection or tests.

    1704.3.3 Wind requirements in the statement of special inspections. Where Section 1705.12 specifies special inspection for wind resistance, the statement of special inspections shall identify the main windforce-resisting systems and wind-resisting components that are subject to special inspections.

    1704.4 Contractor responsibility. Each contractor responsible for the construction of a main wind- or seismic force-resisting system, designated seismic system or a wind- or seismic force-resisting component listed in the statement of special inspections shall submit a written statement of responsibility to the building official and the owner or the owner’s authorized agent prior to the commencement of work on the system or component. The contractor’s statement of responsibility shall contain acknowledgement of awareness of the special requirements contained in the statement of special inspections.

    1704.5 Submittals to the building official. In addition to the submittal of reports of special inspections and tests in accordance with Section 1704.2.4, reports and certificates shall be submitted by the owner or the owner’s authorized agent to the building official for each of the following:

    1. Certificates of compliance for the fabrication of structural, load-bearing or lateral load-resisting members or assemblies on the premises of an approved fabricator in accordance with Section 1704.2.5.1.

    2. Certificates of compliance for the seismic qualification of nonstructural components, supports and attachments in accordance with Section 1705.14.2.

    3. Certificates of compliance for designated seismic systems in accordance with Section 1705.14.3.

    4. Reports of preconstruction tests for shotcrete in accordance with ACI 318.

    5. Certificates of compliance for open web steel joists and joist girders in accordance with Section 2207.5.

    6. Reports of material properties verifying compliance with the requirements of AWS D1.4 for weldability as specified in Section 26.6.4 of ACI 318 for reinforcing bars in concrete complying with a standard other than ASTM A706 that are to be welded.

    7. Reports of mill tests in accordance with Section 20.2.2.5 of ACI 318 for reinforcing bars complying with ASTM A615 and used to resist earthquake-induced flexural or axial forces in the special moment frames, special structural walls or coupling beams connecting special structural walls of seismic force-resisting systems in structures assigned to Seismic Design Category B, C, D, E or F.

    1704.6 Structural observations. Where required by the provisions of Section 1704.6.1, the owner or the owner’s authorized agent shall employ a registered design professional to perform structural observations. The structural observer shall visually observe representative locations of structural systems, details and load paths for general conformance to the approved construction documents.

  • CBC § 1705A.13.7 High relevance — show source text
    TABLE 1705A.13.7—REQUIRED INSPECTIONS OF STORAGE RACK SYSTEMS Col2 Col3 Col4 Col5
    TYPE CONTINUOUS
    INSPECTION    		 PERIODIC
    INSPECTION    		 REFERENCED
    STANDARD    		 IBC REFERENCE
    1. Materials used, to verify compliance with one or more of the
    material test reports in accordance with the approved
    construction documents.    		 — X — —
    2. Fabricated storage rack elements. — X — Section 1704_A_.2.5
    3. Storage rack anchorage installation. — X ANSI/MH16.1
    Section 7.3.2    		 —
    4. Completed storage rack system, to indicate compliance with
    the approved construction documents.    		 — X — —

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    1705 A .13.8 Seismic isolation and damping systems. Periodic special inspection shall be provided for seismic isolation and damping systems in structures assigned to Seismic Design Category D, E or F during the fabrication and installation of isolator units and energy dissipation devices. Continuous special inspection is required for prototype and production testing of isolator units and damping devices.

    1705 A .14 Testing for seismic resistance. Testing for seismic resistance shall be required as specified in Sections 1705 A .14.1 through 1705 A .14.4, unless exempted from special inspections by the exception of Section 1704 A .2.

    1705 A .14.1 Structural steel. Nondestructive testing for seismic resistance shall be in accordance with Section 1705 A .14.1.1 or 1705 A .14.1.2, as applicable.

    1705 A .14.1.1 Seismic force-resisting systems. Nondestructive testing of structural steel in the seismic force-resisting systems in buildings and structures assigned to Seismic Design Category D, E or F shall be performed in accordance with the quality assurance requirements of AISC 341 and this code.

    [DSA-SS, DSA-SS/CC] Quality assurance application is not permitted for the following AISC 341, Chapter J Section: 1. J7 (Welding Inspection and Nondestructive Testing).

    Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    1705 A .14.1.2 Structural steel elements. Nondestructive testing of structural steel elements in the seismic force-resisting systems of buildings and structures assigned to Seismic Design Category D, E or F other than those covered in Section 1705 A .14.1.1, including struts, collectors, chords and foundation elements, shall be performed in accordance with the quality assurance requirements of AISC 341 and this code.

    [DSA-SS, DSA-SS/CC] Quality assurance application is not permitted for the following AISC 341, Chapter J Section: 1. J7 (Welding Inspection and Nondestructive Testing).

  • CBC § 1705.10 High relevance — show source text

    1705.10 Structural integrity of deep foundation elements. Whenever there is a reasonable doubt as to the structural integrity of a deep foundation element, an engineering assessment shall be required. The engineering assessment shall include tests for defects performed in accordance with ASTM D4945, ASTM D5882, ASTM D6760 or ASTM D7949, or other approved method.

    1705.11 Fabricated items. Special inspections of fabricated items shall be performed in accordance with Section 1704.2.5.

    1705.12 Special inspections for wind resistance. Special inspections for wind resistance specified in Sections 1705.12.1 through 1705.12.3, unless exempted by the exceptions to Section 1704.2, are required for buildings and structures constructed in the following areas:

    1. In wind Exposure Category B, where basic wind speed, V, is 150 mph (67 m/sec) or greater.
    2. In wind Exposure Category C or D, where basic wind speed, V, is 140 mph (62.6 m/sec) or greater.

    1705.12.1 Structural wood. Continuous special inspection is required during field gluing operations of elements of the main windforce-resisting system. Periodic special inspection is required for nailing, bolting, anchoring and other fastening of elements of the main windforce-resisting system, including wood shear walls, wood diaphragms, drag struts, braces and hold-downs.

    Exception: Special inspections are not required for wood shear walls, shear panels and diaphragms, including nailing, bolting, anchoring and other fastening to other elements of the main windforce-resisting system, where the lateral resistance is provided by structural sheathing and the specified fastener spacing at panel edges is more than 4 inches (102 mm) on center.

    1705.12.2 Cold-formed steel light-frame construction. Periodic special inspection is required for welding operations of elements of the main windforce-resisting system. Periodic special inspection is required for screw attachment, bolting, anchoring and other fastening of elements of the main windforce-resisting system, including shear walls, braces, diaphragms, collectors (drag struts) and hold-downs.

    Exception: Special inspections are not required for cold-formed steel light-frame shear walls and diaphragms, including screwing, bolting, anchoring and other fastening to components of the windforce-resisting system, where either of the following applies:

    1. The sheathing is gypsum board or fiberboard.
    2. The sheathing is wood structural panel or steel sheets on only one side of the shear wall, shear panel or diaphragm assembly and the specified fastener spacing at the panel or sheet edges is more than 4 inches (102 mm) on center (o.c.).

    1705.12.3 Wind-resisting components. Periodic special inspection is required for fastening of the following systems and components:

    1. Roof covering, roof deck and roof framing connections.
    2. Exterior wall covering and wall connections to roof and floor diaphragms and framing.

    1705.13 Special inspections for seismic resistance. Special inspections for seismic resistance shall be required as specified in Sections 1705.13.1 through 1705.13.9, unless exempted by the exceptions of Section 1704.2.

    Exception: The special inspections specified in Sections 1705.13.1 through 1705.13.9 are not required for structures designed and constructed in accordance with one of the following: 1.

  • CBC § 2.5 High relevance — show source text

    All reports shall describe the nature and extent of inspections and tests, the location where the inspections and tests were performed, and indicate that work inspected or tested was or was not completed in conformance to approved construction documents . Discrepancies shall be brought to the immediate attention of the contractor for correction. If they are not corrected, the discrepancies shall be brought to the attention of the building official and to the registered design professional in responsible charge prior to the completion of that phase of the work. A final report documenting required special inspections and tests, and correction of any discrepancies noted in the inspections or tests, shall be submitted at a point in time agreed upon prior to the start of work by the owner or the owner’s authorized agent to the building official.

    1704 A .2.5 Special inspection of fabricated items. Where fabrication of structural, load-bearing or lateral load-resisting members or assemblies is being conducted on the premises of a fabricator’s shop, special inspections of the fabricated items shall be performed during fabrication.

    1704 A .2.5.1 Fabricator approval. Not permitted by DSA-SS, DSA-SS/CC or OSHPD.

    1704 A .3 Statement of special inspections. Where special inspections or tests are required by Section 1705 A, the registered design professional in responsible charge shall prepare a statement of special inspections in accordance with Section 1704 A .3.1 for submittal by the applicant in accordance with Section 1704 A .2.3.

    Exception: The statement of special inspections is permitted to be prepared by a qualified person approved by the building official for construction not designed by a registered design professional.

    [DSA-SS, DSA-SS/CC] The exception is not permitted by DSA.

    1704 A .3.1 Content of statement of special inspections. The statement of special inspections shall identify the following:

    1. The materials, systems, components and work required to have special inspections or tests by the building official or by the registered design professional responsible for each portion of the work.

    2. The type and extent of each special inspection.

    3. The type and extent of each test.

    4. Additional requirements for special inspections or tests for seismic or wind resistance as specified in Sections 1705 A .12, 1705 A .13 and 1705 A .14.

    5. For each type of special inspection, identification as to whether it will be continuous special inspection, periodic special inspection or performed in accordance with the notation used in the referenced standard where the inspections are defined.

    6. Deferred submittal items that require a supplemental statement of special inspections.

    1704 A .3.2 Seismic requirements in the statement of special inspections. Where Section 1705 A .13 or 1705 A .14 specifies special inspections or tests for seismic resistance, the statement of special inspections shall identify the equipment/components that require special seismic certification and seismic force-resisting systems that are subject to the special inspections or tests.

    1704 A .3.3 Wind requirements in the statement of special inspections. Where Section 1705 A .12 specifies special inspection for wind resistance, the statement of special inspections shall identify the main windforce-resisting systems and wind-resisting components that are subject to special inspections.

    2025 CALIFORNIA BUILDING CODE 17A-5

Frequently asked questions

Do I always need AISC 341 special inspections for steel in seismic systems?

Not always — the CBC requires AISC 341 special inspections for seismic steel in SDC B–F by default (see § 1705.13.1.1), but explicit exceptions exist (for example, certain SDC B/C cases using specific ASCE 7 R values, or where ASCE 7 allows AISC 360 detailing in SDC D–F) — check the exception text in the CBC and ASCE 7 tables .

Who must list the seismic systems that need inspection?

The registered design professional in responsible charge prepares the Statement of Special Inspections and must identify the designated seismic systems and components subject to seismic special inspections per § 1704.3.2 .

Are nondestructive tests (NDT) required for all seismic steel welds?

NDT requirements for seismic structural steel are governed by the same CBC sections that require special inspection; where the CBC invokes AISC 341 for seismic force‑resisting systems, the AISC 341 NDT provisions apply (see § 1705.14.1.1) .

If my design uses AISC 360 detailing, can I avoid AISC 341 inspections?

Possibly — where ASCE 7 permits AISC 360 detailing instead of AISC 341 (ASCE 7 Table 15.4‑1) the CBC exception removes the automatic AISC 341 special‑inspection requirement for those systems; confirm applicability with ASCE 7 and your building official (CBC exception text to § 1705.13.1.1) .

What documentation is required to the building official after inspections?

Certificates of compliance, mill reports and the final reports of special inspections and tests required by the CBC must be submitted to the building official as specified in § 1704.5 .

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California Building Code