CBC · California Building Code

What special inspections are required for wind‑resisting systems and components?

If your project is in the higher wind‑speed areas identified in CBC §1705.12, the code requires special inspections focused on wind‑resisting systems: continuous inspection only for field gluing of structural wood and periodic inspection for most fastening, welding and roof/wall connections, with a narrow exception when panel‑edge fastener spacing exceeds 4 inches.

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

The California Building Code requires special inspections for wind resistance where the basic wind speed and exposure meet specified thresholds; those requirements are set out in § 1705.12 (and the A-code variant § 1705A.12 for certain state agency projects). Special inspections are targeted at the main wind‑force‑resisting systems and wind‑resisting components and specify whether inspection must be continuous (e.g., field gluing of wood elements) or periodic (fastening, welding, etc.). See CBC § 1705.12 and its subsections for the thresholds and the inspection types.

Requirements in detail

Summary: special inspection for wind resistance is required only in areas where wind speed/exposure meet the thresholds; within those areas the code prescribes which materials/operations require continuous vs periodic inspection and lists component fastening inspections. The controlling CBC sections are § 1705.12 (and the A-code equivalent § 1705A.12), with the specific work items described in § 1705.12.1 through § 1705.12.3 (and § 1705A.12.1–.3).

Decision table — thresholds, inspection type and code reference

Decision dimension Value / trigger Inspection required Code Reference
Wind map threshold — Exposure B Basic wind speed V ≥ 150 mph (67 m/s) Special inspections for wind resistance required § 1705.12
Wind map threshold — Exposure C or D Basic wind speed V ≥ 140 mph (62.6 m/s) Special inspections for wind resistance required § 1705.12
Structural wood — field gluing operations Any element of main wind‑force‑resisting system undergoing field gluing Continuous special inspection during field gluing § 1705.12.1 and § 1705A.12.1
Structural wood — fastening (nailing, bolting, anchoring, other fastening) Wood shear walls, diaphragms, drag struts, braces, hold‑downs used as main wind system Periodic special inspection for fastening § 1705.12.1 and § 1705A.12.1
Cold‑formed steel light‑frame Welding and screw attachment/bolting/anchoring of main wind elements Periodic special inspection (welding; mechanical fasteners) § 1705.12.2
Wind‑resisting components (roof/wall connections) Fastening of roof covering, roof deck and roof framing connections; exterior wall covering and wall connections to diaphragms and framing Periodic special inspection of fastening § 1705.12.3 and § 1705A.12.3
Panel edge fastener spacing exception Specified panel‑edge fastener spacing > 4 in. (102 mm) o.c. when lateral resistance provided by structural sheathing Special inspection not required for shear walls/panels/diaphragms (fastening) Exception in § 1705.12.1 and § 1705.12.2

(Readers: confirm exposure category and basic wind speed from Chapter 16 and the adopted wind maps; § 1705.12 only becomes applicable where those thresholds are reached per the first two rows above.)

What “continuous” vs “periodic” means here

  • Continuous special inspection (required for field gluing of structural wood elements) means an inspector must be present during the glue application operations as described in the statement of special inspections and the referenced inspection rules.
  • Periodic special inspection (used for most fastening, welding, etc.) means scheduled, representative inspections of the work at the frequency set by the approved construction documents or building official. The statement of special inspections must identify scope and frequency.

Exceptions & special cases

  • Exemptions from the wind special‑inspection requirements may apply where the exceptions in § 1704.2 (and the A‑code equivalents) apply — the wind special inspections listed in § 1705.12 are required “unless exempted by the exceptions to Section 1704.2.” Always verify those exceptions with the building official.
  • Structural wood exception: if lateral resistance is provided by structural sheathing and the specified fastener spacing at panel edges is more than 4 inches (102 mm) o.c., then special inspections are not required for wood shear walls, shear panels and diaphragms (including the fastening) — see the exception in § 1705.12.1.
  • Cold‑formed steel exception: similar exception language applies for cold‑formed steel light‑frame shear walls and diaphragms where gypsum or fiberboard is used, or where wood panels/steel sheets are on one side only and the panel edge fastener spacing is more than 4 in. o.c.; consult § 1705.12.2 for details.
  • A‑code/agency projects: the California A‑provisions duplicate and sometimes modify these requirements — check § 1705A.12.1 and related A sections for DSA/OSHPD projects.

Also note: the statement of special inspections required at plan check must explicitly identify the main wind‑force‑resisting systems and the wind‑resisting components that will be subject to special inspections, and must list whether inspection will be continuous or periodic, per § 1704.3 and § 1704.3.1.

Common mistakes

  • Treating wind special inspections as automatic for every project: they are required only when the wind‑speed/exposure thresholds in § 1705.12 are met. Check Exposure and V before assuming inspections apply.
  • Confusing continuous vs periodic inspection: field gluing of structural wood is explicitly continuous; fastening (nails, bolts, hold‑downs) is periodic — don’t substitute one for the other.
  • Forgetting to list wind systems/components in the statement of special inspections or to indicate inspection frequency — the statement must identify these items per § 1704.3.3.
  • Overlooking the 4‑inch panel edge‑fastener spacing exception and therefore requiring unnecessary inspections (or, conversely, failing to perform required inspections when spacing is tighter than 4 in.).
  • Using unqualified inspectors: approved agencies must demonstrate competence and special inspectors must meet qualification requirements referenced in the code (see § 1704A.2.1 for inspector qualifications where A‑provisions apply).

Worked example — concrete scenario with numbers

Scenario: A 3‑story wood‑framed building in Exposure C where the governing basic wind speed for the site is 145 mph (V = 145 mph).

Step 1 — threshold check: Exposure C with V = 145 mph is ≥ 140 mph, so wind special inspections are required under § 1705.12.

Step 2 — identify affected systems (example assumptions): the main lateral system uses wood shear walls, wood diaphragms, hold‑downs and glued laminated collectors; roof is a sheathed wood deck with mechanical fasteners and a conventional roof covering.

Step 3 — apply required inspections:

  • Field gluing of glued‑laminated collectors (if performed in the field): continuous special inspection during gluing per § 1705.12.1. The special inspector must be present for the glue application operations.
  • Nailing/bolting/anchoring/hold‑down installation for the shear walls and diaphragms: periodic special inspection for these fastenings per § 1705.12.1.
  • Fastening of roof deck to framing and roof covering connections: periodic special inspection of fastening per § 1705.12.3.

Step 4 — check exceptions: if the shear walls rely on structural sheathing and the specified panel‑edge fastener spacing at the panel edges is 5 in. o.c. (greater than 4 in.), then the special‑inspection requirement for those shear‑wall fastenings would be exempt per the exception in § 1705.12.1; if spacing is 3 in. o.c., the periodic inspection is required. Confirm spacing from the construction documents.

Step 5 — documentation: ensure the statement of special inspections lists the main wind systems and each inspection type (continuous or periodic) as required by § 1704.3.1 and submit contractor statements of responsibility where required by § 1704.4.

Related provisions

  • § 1705.12 — Special inspections for wind resistance (thresholds and general applicability).
  • § 1705.12.1 — Structural wood: continuous special inspection for field gluing; periodic for fastening (with 4‑inch exception).
  • § 1705.12.2 — Cold‑formed steel light‑frame construction: periodic special inspection for welding and fastening (with exceptions).
  • § 1705.12.3 — Wind‑resisting components: periodic inspection for roof and exterior wall fastening.
  • § 1705A.12.1 — A‑provisions (structural wood) — mirrors continuous/periodic requirements for A‑agency projects.
  • § 1704.3 / § 1704.3.1 — Statement of special inspections: content must identify wind systems/components and whether continuous or periodic.
  • § 1704.4 — Contractor responsibility: contractor statements of responsibility for wind/seismic systems listed in the statement.
  • § 1704.2 (exceptions) — Explains situations where special inspections may be exempted; § 1705.12 requirements apply unless exempted by those exceptions.

Code references

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

  • 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 § 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 § 1705.8 High relevance — show source text
    TABLE 1705.8—REQUIRED SPECIAL INSPECTIONS AND TESTS OF CAST-IN-PLACE DEEP FOUNDATION ELEMENTS Col2 Col3
    TYPE CONTINUOUS
    SPECIAL INSPECTION    		 PERIODIC SPECIAL
    INSPECTION
    1. Inspect drilling operations and maintain complete and accurate records for each element. X —
    2. Verify placement locations and plumbness, confirm element diameters, bell diameters (if
    applicable), lengths, embedment into bedrock (if applicable) and adequate end-bearing strata
    capacity. Record concrete or grout volumes.    		 X —
    3. For concrete elements, perform tests and additional special inspections in accordance with
    Section 1705.3.    		 In accordance with Section 1705.3 In accordance with Section 1705.3

    1705.9 Helical pile foundations. Continuous special inspections shall be performed during installation of helical pile foundations. The information recorded shall include installation equipment used, pile dimensions, tip elevations, final depth, final installation torque and other pertinent installation data as required by the registered design professional in responsible charge. The approved

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    SPECIAL INSPECTIONS AND TESTS

    geotechnical report and the construction documents prepared by the registered design professional shall be used to determine compliance.

    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.

  • 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 § 3.1 High relevance — show source text

    [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.

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    SPECIAL INSPECTIONS AND TESTS

    1704 A .4 Contractor responsibility. Each contractor responsible for the construction of a main wind- or seismic force-resisting system, installation of equipment/components requiring special seismic certification 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. [DSA-SS, DSA-SS/CC] The contractor’s statement is required only when specified on the approved construction documents.

    1704 A .5 Submittals to the building official. In addition to the submittal of reports of special inspections and tests in accordance with Section 1704 A .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. Reserved.

    2. Reserved.

    3. Certificates of compliance for equipment/components requiring special seismic certification in accordance with Section 1705 A .14.3.

    4. Reports of preconstruction tests for shotcrete in accordance with ACI 318 and Section 1705A.3.9.2.

    5. Certificates of compliance for open web steel joists and joist girders in accordance with Section 2207 A. 5.

  • CBC § 1704.5 High relevance — show source text

    At completion of fabrication, the approved fabricator 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 the work was performed in accordance with the approved construction documents.

    1704.3 Statement of special inspections. Where special inspections or tests are required by Section 1705, the registered design professional in responsible charge shall prepare a statement of special inspections in accordance with Section 1704.3.1 for submittal by the applicant in accordance with Section 1704.2.3.

    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.

    1704.3.1 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 1705.12, 1705.13 and 1705.14.

    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.

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    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.

  • CBC § 1705A.8 High relevance — show source text
    TABLE 1705A.8—REQUIRED SPECIAL INSPECTIONS AND TESTS OF CAST-IN-PLACE DEEP FOUNDATION ELEMENTS Col2 Col3
    TYPE CONTINUOUS
    SPECIAL INSPECTION    		 PERIODIC
    SPECIAL INSPECTION
    1. Inspect drilling operations and maintain complete and accurate records for each element. X —
    2. Verify placement locations and plumbness, confirm element diameters, bell diameters (if
    applicable), lengths, embedment into bedrock (if applicable) and adequate end-bearing
    strata capacity. Record concrete or grout volumes.    		 X —
    3. For concrete elements, perform tests and additional special inspections in accordance
    with Section 1705_A_.3.    		 In accordance with Section 1705_A_.3 In accordance with Section 1705_A_.3

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    1705A.8.1 Micropile tests. Micropile preproduction and production load tests shall be in accordance with Section 1810A.3.10.4.

    1705 A .9 Helical pile foundations. Continuous special inspections shall be performed during installation of helical pile foundations. The information recorded shall include installation equipment used, pile dimensions, tip elevations, final depth, final installation torque and other pertinent installation data as required by the registered design professional in responsible charge. The approved geotechnical report and the construction documents prepared by the registered design professional shall be used to determine compliance.

    1705A.9.1 Helical pile tests. Helical pile preproduction and production load tests shall be in accordance with Section 1810A.3.1.5.1.

    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.

  • CBC § 1705.14.3.1 High relevance — show source text

    1705.14.3.1 Special seismic certification. [OSHPD 1R, 2 & 5] Special seismic certification shall be required in accordance with Section 1705A.14.3. for all of the following: 1. Life-safety components, such as emergency and standby power systems, mechanical smoke removal systems and fire sprinkler/fire protection systems. 2. Medical, mechanical and electrical equipment and components required for life support for patients. 3. On-site power resources (PVs, batteries, fuel cells, etc.) provided to replace, in whole or in part, the public or private elec- tric utility service. 4. [OSHPD 2] Alternate power systems including:

    a. Generators.

    b. UPS and batteries.

    c. Renewable electrical generation and control equipment. d. Panelboards as defined in the California Electrical Code (CEC) Article 100.

    e. Manual and automatic transfer switches.

    f. Switchgear and switchboards.

    1705.14.4 Seismic isolation systems. Seismic isolation systems in seismically isolated structures assigned to Seismic Design Category B, C, D, E or F shall be tested in accordance with Section 17.8 of ASCE 7.

    [BF] 1705.15 Sprayed fire-resistive materials (SFRM). Special inspections and tests of sprayed fire-resistive materials (SFRM) applied to floor, roof and wall assemblies and structural members shall be performed in accordance with Sections 1705.15.1 through 1705.15.6. Special inspections shall be based on the fire-resistance design as designated in the approved construction documents. The tests set forth in this section shall be based on samplings from specific floor, roof and wall assemblies and structural members. Special inspections and tests shall be performed during construction with an additional visual inspection after the rough installation of electrical, automatic sprinkler systems, mechanical and plumbing systems and suspension systems for ceilings, and before concealment where applicable. The required sample size shall not exceed 110 percent of that specified by the referenced standards in Sections 1705.15.4.1 through 1705.15.4.9.

    [BF] 1705.15.1 Physical and visual tests. The special inspections and tests shall include the following to demonstrate compliance with the listing and the fire-resistance rating:

    1. Condition of substrates.

    2. Thickness of application.

    3. Density in pounds per cubic foot (kg/m [3] ).

    4. Bond strength adhesion/cohesion.

    5. Condition of finished application.

    [BF] 1705.15.2 Structural member surface conditions. The surfaces shall be prepared in accordance with the approved fireresistance design and the written instructions of approved manufacturers. The prepared surface of structural members to be sprayed shall be inspected by the special inspector before the application of the SFRM.

    [BF] 1705.15.3 Application. The substrate shall have a minimum ambient temperature before and after application as specified in the written instructions of approved manufacturers. The area for application shall be ventilated during and after application as required by the written instructions of approved manufacturers.

    [BF] 1705.15.4 Thickness. Not more than 10 percent of the thickness measurements of the SFRM applied to floor, roof and wall assemblies and structural members shall be less than the thickness required by the approved fire-resistance design, and none shall be less than the minimum allowable thickness required by Section 1705.15.4.1.

  • CBC § 1.1 High relevance — show source text

    1705 A .1 General. Special inspections and tests of elements and nonstructural components of buildings and structures shall meet the applicable requirements of this section.

    1705 A .1.1 Special cases. Special inspections and tests shall be required for proposed work that is, in the opinion of the building official, unusual in its nature, such as, but not limited to, the following examples:

    1. Construction materials and systems that are alternatives to materials and systems prescribed by this code.
    2. Unusual design applications of materials described in this code.
    3. Materials and systems required to be installed in accordance with additional manufacturer’s instructions that prescribe requirements not contained in this code or in standards referenced by this code.

    1705 A .2 Steel construction. The special inspections and nondestructive testing of steel construction in buildings, structures and portions thereof shall be in accordance with this section.

    Exception: Special inspections of the steel fabrication process shall not be required where the fabrication process for the entire building or structure does not include any welding, thermal cutting or heating operation of any kind. In such cases, the fabricator shall be required to submit a detailed procedure for material control that demonstrates the fabricator’s ability to maintain suitable records and procedures such that, at any time during the fabrication process, the material specification and grade for the main stress-carrying elements are capable of being determined. Mill test reports shall be identifiable to the main stress-carrying elements where required by the approved construction documents.

    1705 A .2.1 Structural steel. Special inspections and nondestructive testing of structural steel elements in buildings, structures and portions thereof shall be in accordance with the quality assurance requirements of AISC 360 and this code.

    Exception: Special inspection of railing systems composed of structural steel elements shall be limited to welding inspection of welds at the base of cantilevered rail posts.

    The following provisions of AISC 360, Chapter N are not permitted: 1. N5, Item 3 (Coordinated Inspection). 2. N6 (Approved Fabricators and Erectors). 3. [DSA-SS, DSA-SS/CC] Quality assurance application of: a. N5, Item 2 (Quality Assurance). b. N5, Item 4 (Inspection of Welding). c. N7 (Nonconforming Material and Workmanship).

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    [DSA-SS, DSA-SS/CC] Additionally, the requirements of Table 1705A.2.1 of the California Building Code shall apply.

    [DSA-SS, DSA-SS/CC] References to specified standards in Table 1705A.2.1 apply only to those structural systems and elements required to comply with those by this code.

    [DSA-SS, DSA-SS/CC] Replace AISC 360, Section N5.5(b), as follows:

  • CBC § 2.1 High relevance — show source text

    1704 A .2.1 Special inspector qualifications. Prior to the start of the construction, the approved agencies shall provide written documentation to the building official demonstrating the competence and relevant experience or training of the special inspectors who will perform the special inspections and tests during construction. Experience or training shall be considered to be relevant where the documented experience or training is related in complexity to the same type of special inspection or testing activities for projects of similar complexity and material qualities. These qualifications are in addition to qualifications specified in other sections of this code.

    The registered design professional in responsible charge and engineers of record involved in the design of the project are permitted to act as an approved agency and their personnel are permitted to act as special inspectors for the work designed by them, provided they qualify as special inspectors.

    1704 A .2.2 Access for special inspection. The construction or work for which special inspection or testing is required shall remain accessible and exposed for special inspection or testing purposes until completion of the required special inspections or tests.

    1704 A .2.3 Statement of special inspections. The applicant shall submit a statement of special inspections prepared by the regis- tered design professional in general responsible charge in accordance with Section 107.1 as a condition for construction documents review . This statement shall be in accordance with Section 1704 A .3.

    [DSA-SS, DSA-SS/CC] Reference to Section 107.1 shall be to the California Administrative Code instead.

    1704 A .2.4 Report requirement. The inspector(s) of record and approved agencies shall keep records of special inspections and tests. The inspector of record and approved agency shall submit reports of special inspections and tests to the building official and to the registered design professional in responsible charge at frequencies required by the approved construction documents or building official as required by the California Administrative Code . 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.

  • CBC § 1705A.2.6 High relevance — show source text
    TABLE 1705A.2.6—SPECIAL INSPECTIONS OF METAL BUILDING SYSTEMS Col2 Col3
    TYPE CONTINUOUS SPECIAL
    INSPECTION    		 PERIODIC SPECIAL
    INSPECTION
    1. Installation of rafter/beam flange braces and column flange braces. — X
    2. Installation of purlins and girts, including specified lapping. — X
    3. Purlin and girt restraint/bridging/bracing. — X
    4. Installation of X-bracing, tightened to remove any sag. — X

    1705A.2.7 Special inspections and tests of structural welding. Special inspection and testing (including nondestructive testing) of all shop and field welding operations shall be in accordance with this section, and Sections 1705A.2.1, 1705A.2.2, 1705A.13.1 and 1705A.14.1, as applicable. Special inspections shall be performed by an approved welding inspector. The minimum requirements for a qualified welding inspector shall be as those for an AWS Certified Welding Inspector (CWI), as defined in the provisions of the AWS QC1 or AWS B5.1.

    The welding inspector shall make a systematic daily record of all welds. This record shall include:

    1. Identification marks of welders.

    2. List of defective welds.

    3. Manner of correction of defects.

    The welding inspector shall check the material, details of construction and procedure, as well as workmanship of the welds. The special inspector shall verify that the installation and testing of end-welded stud shear connectors is in accordance with the require- ments of Section 2216A.2 ( [DSA-SS/CC] 2215.6.2) and the approved construction documents. The approved agency shall furnish the architect, structural engineer and the enforcement agency with a verified report that the welding has been done in conformance with AWS D1.1, D1.3, D1.4, D1.6 and D1.8, as applicable and the approved construction documents.

    [DSA-SS, DSA-SS/CC] Welding inspector approval by the enforcement agency shall occur when specified in the California Administra- tive Code. Nondestructive testing shall be performed by qualified NDT Level II personnel employed by the approved agency. Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

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    1705A.2.8 Special inspection and tests of high-strength fastener assemblies. Special inspections and tests for high-strength fasteners shall be in accordance with this section and Section 1705A.2.1. High-strength bolts, nuts and washers shall be sampled and tested by an approved agency for conformance with the requirements of applicable ASTM standards [OSHPD 1 & 4] and in accor- dance with Section 2216A.1.

  • 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.

Frequently asked questions

When are wind special inspections required?

When the project is in Exposure Category B with basic wind speed V ≥ 150 mph, or in Exposure Category C or D with V ≥ 140 mph — see § 1705.12 for the thresholds and applicability.

Is field gluing always a continuous special inspection?

Yes — where field gluing is performed on elements of the main wind‑force‑resisting system, the code requires continuous special inspection during the field gluing operations (§ 1705.12.1 and § 1705A.12.1).

Are nailing and bolting always continuously inspected?

No — for structural wood the code requires periodic special inspection (not continuous) for nailing, bolting, anchoring and other fastening of main wind elements; only field gluing is continuous (§ 1705.12.1).

Does the 4‑inch panel edge spacing rule remove the need for inspection?

If lateral resistance is provided by structural sheathing and the specified fastener spacing at panel edges is greater than 4 in. o.c., then the special inspection for those shear walls/panels/diaphragms (fastening) is not required — see the exception in § 1705.12.1.

Who must list the wind systems for inspection at plan check?

The registered design professional in responsible charge (or an approved qualified person where permitted) prepares the statement of special inspections and must identify the main wind‑force‑resisting systems and wind‑resisting components as required by § 1704.3.3.

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Seismic, Wind, Nonstructural Seismic Certification, Fire & Smoke Testing

California Building Code