CBC · California Building Code

What special inspections/tests are required for deep foundations (driven, cast-in-place, helical)?

For homeowners: the California Building Code requires continuous special inspection during installation of driven, drilled (cast‑in‑place) and helical foundation elements; a geotechnical engineer’s representative must observe operations, record installation data (blows, torque, depths, concrete/grout volumes), and report results so the authority can confirm the foundation meets the approved design.

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

The CBC requires continuous special inspection during installation of driven, cast‑in‑place and helical deep foundation elements, and specifies the items that must be observed and recorded for each type. The required inspections and tests are listed in Table 1705.7 for driven deep foundations, Table 1705.8 for cast‑in‑place deep foundation elements, and Section 1705.9 for helical piles; the approved geotechnical report and construction documents govern final scope and any additional tests (§1705.7, §1705.8, §1705.9) .

Requirements in detail

High‑level rule

  • Driven deep foundations: continuous observation by a qualified representative of the geotechnical engineer; required records of driving, hammer, blows, elevations and more; concrete/steel elements may trigger additional inspections per the applicable material sections (§1705.7; see Table 1705.7) .
  • Cast‑in‑place deep foundations (drilled shafts, caissons, micropiles, etc.): continuous inspection of drilling and placement operations and verification of dimensions, embedment and volumes; concrete elements require tests/inspections per the concrete section (§1705.8; see Table 1705.8) .
  • Helical piles: continuous special inspection during installation with recording of installation equipment, pile dimensions, tip elevations, final depth, final installation torque and other data as required by the registered design professional (§1705.9) .

Decision‑relevant summary table

Element type Key continuous inspections/tests required Any periodic items Code reference
Driven deep foundations (piles) Verify materials/sizes; inspect driving operations; record hammer type, blows per foot, required penetration to achieve design capacity; tip & butt elevations; document damage; conduct test element capacity/load tests as required Material‑specific periodic inspections per §1705.2 (steel) or §1705.3 (concrete) when applicable §1705.7; Table 1705.7
Cast‑in‑place deep foundations (drilled shafts, micropiles) Inspect drilling operations; verify locations, plumbness, diameters, lengths, embedment; record concrete/grout volumes; for concrete elements follow §1705.3 testing Concrete testing and additional inspections per §1705.3 §1705.8; Table 1705.8
Helical piles Continuous inspection; record installation equipment, pile geometry, tip elevations, final depth, final installation torque and other RDP‑required data; use geotechnical report to determine acceptance N/A (continuous inspection is required; some projects require load or production tests as determined by RDP) §1705.9

What must be recorded (decision‑relevant items)

  • Driving records (number of blows per foot, permanent penetration under last blows if dynamic formula used, tip/butt elevations), hammer type and size, identifying mark for each element — required for driven piles (§1705.7, Table 1705.7) .
  • For drilled/grouted elements: drilling logs, verification of diameter and bell (if used), embedment into rock (if applicable), and concrete/grout volumes — required for cast‑in‑place elements (§1705.8, Table 1705.8) .
  • For helical piles: final installation torque and other installation data specified by the registered design professional; installation torque must be recorded and compared to design/manufacturer criteria (§1705.9; see also the related installation torque requirement in the soils chapter) .

Interaction with material‑specific inspection requirements

  • When a driven element is steel, the additional steel inspection requirements in §1705.2 apply (welding, coating, etc.) as noted in Table 1705.7 .
  • When elements are concrete or concrete‑filled, tests and special inspections required by §1705.3 apply (slump, cylinders, reinforcement inspection, concrete placement inspection), as cross‑referenced in Tables 1705.7 and 1705.8 .

Exceptions & special cases

  • The CBC language emphasizes that the approved geotechnical report and the construction documents determine additional or modified inspection/test requirements; the tables provide baseline mandatory continuous items but the RDP/geotechnical report may require extra tests (e.g., production/verification load tests, micropile-specific tests) (§1705.7, §1705.8, §1705.9) .
  • Where allowable pile capacity is determined by a dynamic formula, the geotechnical representative must report the design formula used and the permanent penetration under the last 10 blows — a reporting requirement, not a fixed numeric penetration limit (§1705.7.1) .
  • Micropiles and specialty elements may have specific test protocols or preproduction/production load tests called out elsewhere in the Code or in the geotechnical report; the statement of special inspections must reflect those deferred submittals (§1705.8 notes; see also referenced sections for micropile testing) .

Common mistakes

  • Treating the table items as optional: continuous observation and the listed record‑keeping are mandatory baseline requirements — not optional checklists (§1705.7, §1705.8, §1705.9) .
  • Omitting the geotechnical representative: driven piles must be continuously observed by a qualified representative of the geotechnical engineer; failure to document that observation and the required reports is a frequent deficiency (§1705.7.1) .
  • Forgetting material‑specific cross‑references: when a deep foundation is concrete or steel, inspectors must also follow the concrete (§1705.3) or steel (§1705.2) special inspection/testing requirements cited in the tables .
  • Not including required items in the Statement of Special Inspections: the RDP must list the required special inspections/tests per §1704.3; failing to include deep‑foundation items or deferred submittals there causes confusion and enforcement delays (§1704.3) .
  • For helical piles, failing to record final installation torque or exceeding manufacturer torque limits — torque is an acceptance criterion and must be recorded (§1705.9; see also installation torque guidance in the soils sections) .

Worked example — applying the rule to a concrete driven pile program

Scenario: A mid‑rise building uses driven concrete‑filled pipe piles. The approved geotechnical report prescribes pile capacities determined partly by dynamic formula and requires some production load tests.

  1. Special inspection scope: Per §1705.7 and Table 1705.7, the geotechnical engineer’s qualified representative must continuously observe pile driving, verify element materials and lengths, record hammer type and blows per foot, record tip and butt elevations, and document any damage. Because piles are concrete‑filled, follow §1705.3 for concrete testing and placement inspections (slump, cylinders, reinforcement, placement observations) .
  2. Records: The inspector will produce driving logs showing blows/ft at each depth, the permanent penetration over the last 10 blows (because a dynamic formula is used), the calculated dynamic capacity (design formula documented), and concrete volume per pile — all items called for by §1705.7 Table 1705.7 and §1705.3 cross‑references .
  3. Acceptance steps: Compare recorded dynamic capacities to design values; perform the required production or verification load test(s) noted in the geotechnical report; submit the geotechnical engineer’s verified report to the enforcement agency as required by the Code (§1705.7.1 and reporting requirements) .
    (Notes: numbers such as target blows/ft or test loads come from the geotechnical report — the Code prescribes what to observe and record, not specific numeric blow‑counts for every project) .

Related provisions (select)

  • §1704.3 — Statement of special inspections (content and who prepares it) .
  • §1705.3 — Special inspections and tests for concrete (applies to concrete deep foundation elements) .
  • §1705.2 — Special inspections for steel construction (applies when driven elements are steel) .
  • §1705.10 — Structural integrity of deep foundation elements; testing methods (ASTM references) when integrity is in doubt .
  • §1810.4.11 — Helical pile installation torque and embedment criteria (installation torque limits and RDP criteria) .

Code references

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

  • CBC § 1705.2. High relevance — show source text

    Inspect driving operations and maintain complete and accurate records for each element.|X|—| |4. Verify placement locations and plumbness, confirm type and size of hammer, record number
    of blows per foot of penetration, determine required penetrations to achieve design capacity,
    record tip and butt elevations and document any damage to foundation element.|X|—| |5. For steel elements, perform additional special inspections in accordance with Section 1705.2.|In accordance with Section 1705.2|In accordance with Section 1705.2| |6. For concrete elements and concrete-filled 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| |7.For specialty elements, perform additional inspections as determined by the registered design
    professional in responsible charge.|In accordance with Statement of Special
    Inspections|In accordance with Statement of Special
    Inspections|

    1705.7.1 Driven deep foundations observation. [OSHPD 1R, 2 & 5] The installation of driven deep foundations shall be continu- ously observed by a qualified representative of the geotechnical engineer responsible for that portion of the project.

    The representative of the geotechnical engineer shall make a report of the deep foundation pile-driving operation giving such pertinent data as the physical characteristics of the deep foundation pile-driving equipment, identifying marks for each deep founda- tion pile, total depth of embedment for each deep foundation; and when the allowable deep foundation pile loads are determined by a dynamic load formula, the design formula used, and the permanent penetration under the last 10 blows. One copy of the report shall be sent to the enforcement agency.

    1705.8 Cast-in-place deep foundations. Special inspections and tests shall be performed during installation of cast-in-place deep foundation elements as specified in Table 1705.8. The approved geotechnical report and the construction documents prepared by the registered design professionals shall be used to determine compliance.

    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.

  • CBC § 1810.4.11 High relevance — show source text

    During withdrawal of the casing, the grout level inside the casing shall be monitored to verify that the flow of grout inside the casing is not obstructed. 2. For a micropile or portion thereof grouted in an open drill hole in soil without temporary casing, the minimum design diameter of the drill hole shall be verified by a suitable device during grouting. 3. For micropiles designed for end bearing, a suitable means shall be employed to verify that the bearing surface is properly cleaned prior to grouting. 4. Subsequent micropiles shall not be drilled near elements that have been grouted until the grout has had sufficient time to harden.

    1. Micropiles shall be grouted as soon as possible after drilling is completed.
    2. For micropiles designed with a full-length casing, the casing shall be pulled back to the top of the bond zone and reinserted or some other suitable means employed to ensure grout coverage outside the casing.

    1810.4.11 Helical piles. Helical piles shall be installed to specified embedment depth and torsional resistance criteria as determined by a registered design professional. The torque applied during installation shall not exceed the manufacturer’s rated maximum installation torque resistance of the helical pile.

    1810.4.12 Special inspection. Special inspections in accordance with Sections 1705.7 and 1705.8 shall be provided for driven and cast-in-place deep foundation elements, respectively. Special inspections in accordance with Section 1705.9 shall be provided for helical piles.

    SECTION 1811—PRESTRESSED ROCK AND SOIL FOUNDATION ANCHORS [OSHPD 1R, 2 & 5]

    1811.1 General. The requirements of this section address the use of vertical rock and soil anchors in resisting seismic or wind overturn- ing forces, resulting in tension on shallow foundations.

    1811.2 Adoption. Except for the modifications as set forth in Sections 1811.3 and 1811.4, all prestressed rock and soil foundation anchors shall comply with PTI Recommendations for Prestressed Rock and Soil Anchors.

    1811.3 Geotechnical requirements . The geotechnical report for the Prestressed Rock & Soil Foundation Anchors shall address the following: 1. Minimum diameter and minimum spacing for the anchors including consideration of group effects. 2. Maximum unbonded length and minimum bonded length of the tendon.

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    SOILS AND FOUNDATIONS

    3. Maximum recommended anchor tension capacity based upon the soil or rock strength/grout bond and anchor depth/spacing. 4. Allowable bond stress at the ground/grout interface and applicable factor of safety for ultimate bond stress. 5. Anchor axial tension stiffness recommendations at the anticipated anchor axial tension displacements, when required for structural analysis. 6. Minimum grout pressure for installation and post-grout pressure. 7. Class I corrosion protection is required for all permanent and extended temporary anchors in service more than 2 years. A mini- mum of Class II corrosion protection is required for temporary anchors in service less than or equal to 2 years. 8. Performance test shall be at a minimum of 1.6 times the design loads, but shall not exceed 80 percent of the specified minimum _tensile strength of the tendons. There shall be a minimum of two preproduction test anchors.

  • 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 § 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 § 1705.8 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 § 1705A.6.2 High relevance — show source text

    A verified report shall be submitted by the geotechnical engineer as required by the California Administrative Code. The report shall indicate that all tests and inspections required by the approved construction documents were completed and whether the tested materials and/or inspected work meet the requirements of the approved construction documents.

    1705A.6.2 Earth-retaining shoring. Special inspections and tests of earth-retaining shoring shall be in accordance with applicable portions of Section 1812A.

    1705A.6.3 Vibro stone columns. Special inspections and tests of vibro stone columns for ground improvement shall be in accordance with Section 1813A.5.

    1705 A .7 Driven deep foundations. Special inspections and tests shall be performed during installation of driven deep foundation elements as specified in 1810A.3.3.1.2 and Table 1705 A .7. The approved geotechnical report and the construction documents prepared by the registered design professionals shall be used to determine compliance.

    TABLE 1705A.7—REQUIRED SPECIAL INSPECTIONS AND TESTS OF DRIVEN DEEP FOUNDATION ELEMENTS Col2 Col3
    TYPE CONTINUOUS
    SPECIAL INSPECTION    		 PERIODIC SPECIAL
    INSPECTION
    1. Verify element materials, sizes and lengths comply with the requirements. X —
    2. Determine capacities of test elements and conduct additional load tests, as required. X —
    3. Inspect driving operations and maintain complete and accurate records for each element. X —
    4. Verify placement locations and plumbness, confirm type and size of hammer, record number
    of blows per foot of penetration, determine required penetrations to achieve design capacity,
    record tip and butt elevations and document any damage to foundation element.    		 X —
    5. For steel elements, perform additional special inspections in accordance with Section 1705_A_.2. In accordance with Section 1705_A_.2 In accordance with Section 1705_A_.2
    6. For concrete elements and concrete-filled 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
    7. For specialty elements, perform additional inspections as determined by the registered design
    professional in responsible charge.    		 In accordance with Statement of Special
    Inspections    		 In accordance with Statement of Special
    Inspections

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    SPECIAL INSPECTIONS AND TESTS

    1705A.7.1 Driven deep foundations observation. The installation of driven deep foundations shall be continuously observed by a qualified representative of the geotechnical engineer responsible for that portion of the project.

    The representative of the geotechnical engineer shall make a report of the deep foundation pile-driving operation giving such pertinent data as the physical characteristics of the deep foundation pile-driving equipment, identifying marks for each deep founda- tion pile, total depth of embedment for each deep foundation; and when the allowable deep foundation pile loads are determined by a dynamic load formula, the design formula used, and the permanent penetration under the last 10 blows. One copy of the report shall be sent to the enforcement agency.

  • CBC § 1705.7 High relevance — show source text

    The duties of the geotechnical engineer or his or her qualified representative shall include, but need not be limited to, the inspec- tion of cleared areas and benches prepared to receive fill; inspection of the removal of all unsuitable soils and other materials; the approval of soils to be used as fill material; the inspection of placement and compaction of fill materials; the testing of the completed fills; and the inspection or review of geotechnical drainage devices, buttress fills or other similar protective measures in accordance with the approved construction documents.

    A verified report shall be submitted by the geotechnical engineer as required by the California Administrative Code. The report shall indicate that all tests and inspections required by the approved construction documents were completed and whether the tested materials and/or inspected work meet the requirements of the approved construction documents.

    1705.7 Driven deep foundations. Special inspections and tests shall be performed during installation of driven deep foundation elements as specified in Table 1705.7. The approved geotechnical report and the construction documents prepared by the registered design professionals shall be used to determine compliance.

    TABLE 1705.7—REQUIRED SPECIAL INSPECTIONS AND TESTS OF DRIVEN DEEP FOUNDATION ELEMENTS Col2 Col3
    TYPE CONTINUOUS
    SPECIAL INSPECTION    		 PERIODIC
    SPECIAL
    INSPECTION
    1. Verify element materials, sizes and lengths comply with the requirements. X —
    2. Determine capacities of test elements and conduct additional load tests, as required. X —
    3. Inspect driving operations and maintain complete and accurate records for each element. X —
    4. Verify placement locations and plumbness, confirm type and size of hammer, record number
    of blows per foot of penetration, determine required penetrations to achieve design capacity,
    record tip and butt elevations and document any damage to foundation element.    		 X —
    5. For steel elements, perform additional special inspections in accordance with Section 1705.2. In accordance with Section 1705.2 In accordance with Section 1705.2
    6. For concrete elements and concrete-filled 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
    7.For specialty elements, perform additional inspections as determined by the registered design
    professional in responsible charge.    		 In accordance with Statement of Special
    Inspections    		 In accordance with Statement of Special
    Inspections

    1705.7.1 Driven deep foundations observation. [OSHPD 1R, 2 & 5] The installation of driven deep foundations shall be continu- ously observed by a qualified representative of the geotechnical engineer responsible for that portion of the project.

    The representative of the geotechnical engineer shall make a report of the deep foundation pile-driving operation giving such pertinent data as the physical characteristics of the deep foundation pile-driving equipment, identifying marks for each deep founda- tion pile, total depth of embedment for each deep foundation; and when the allowable deep foundation pile loads are determined by a dynamic load formula, the design formula used, and the permanent penetration under the last 10 blows. One copy of the report shall be sent to the enforcement agency.

  • CBC § 17A-15 High relevance — show source text

    For steel elements, perform additional special inspections in accordance with Section 1705_A_.2.|In accordance with Section 1705_A_.2|In accordance with Section 1705_A_.2| |6. For concrete elements and concrete-filled 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| |7. For specialty elements, perform additional inspections as determined by the registered design
    professional in responsible charge.|In accordance with Statement of Special
    Inspections|In accordance with Statement of Special
    Inspections|

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    SPECIAL INSPECTIONS AND TESTS

    1705A.7.1 Driven deep foundations observation. The installation of driven deep foundations shall be continuously observed by a qualified representative of the geotechnical engineer responsible for that portion of the project.

    The representative of the geotechnical engineer shall make a report of the deep foundation pile-driving operation giving such pertinent data as the physical characteristics of the deep foundation pile-driving equipment, identifying marks for each deep founda- tion pile, total depth of embedment for each deep foundation; and when the allowable deep foundation pile loads are determined by a dynamic load formula, the design formula used, and the permanent penetration under the last 10 blows. One copy of the report shall be sent to the enforcement agency.

    1705 A .8 Cast-in-place deep foundations. Special inspections and tests shall be performed during installation of cast-in-place deep foundation elements as specified in 1810A.3.3.1.2 and Table 1705 A .8. The approved geotechnical report and the construction documents prepared by the registered design professionals shall be used to determine compliance.

    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.

  • CBC § 4.11 High relevance — show source text

    SOILS AND FOUNDATIONS

    pumped through a tremie pipe extending to the bottom of the element until grout of suitable quality returns at the top of the element. The following requirements apply to specific installation methods:

    1. For micropiles grouted inside a temporary casing, the reinforcing bars shall be inserted prior to withdrawal of the casing. The casing shall be withdrawn in a controlled manner with the grout level maintained at the top of the element to ensure that the grout completely fills the drill hole. During withdrawal of the casing, the grout level inside the casing shall be monitored to verify that the flow of grout inside the casing is not obstructed.

    2. For a micropile or portion thereof grouted in an open drill hole in soil without temporary casing, the minimum design diameter of the drill hole shall be verified by a suitable device during grouting.

    3. For micropiles designed for end bearing, a suitable means shall be employed to verify that the bearing surface is properly cleaned prior to grouting.

    4. Subsequent micropiles shall not be drilled near elements that have been grouted until the grout has had sufficient time to harden.

    5. Micropiles shall be grouted as soon as possible after drilling is completed.

    6. For micropiles designed with a full-length casing, the casing shall be pulled back to the top of the bond zone and reinserted or some other suitable means employed to ensure grout coverage outside the casing.

    1810 A .4.11 Helical piles. Helical piles shall be installed to specified embedment depth and torsional resistance criteria as determined by a registered design professional. The torque applied during installation shall not exceed the manufacturer’s rated maximum installation torque resistance of the helical pile.

    1810 A .4.12 Special inspection. Special inspections in accordance with Sections 1705 A .7 and 1705 A .8 shall be provided for driven and cast-in-place deep foundation elements, respectively. Special inspections in accordance with Section 1705 A .9 shall be provided for helical piles.

    SECTION 1811A—PRESTRESSED ROCK AND SOIL FOUNDATION ANCHORS

    1811A.1 General. The requirements of this section address the use of vertical rock and soil anchors in resisting seismic or wind overturn- ing forces resulting in tension on shallow foundations.

    1811A.2 Adoption. Except for the modifications as set forth in Sections 1811A.3 and 1811A.4, all prestressed rock and soil foundation anchors shall comply with PTI Recommendations for Prestressed Rock and Soil Anchors.

    1811A.3 Geotechnical requirements. Geotechnical report for the prestressed rock and soil foundation anchors shall address the following: 1. Minimum diameter and minimum spacing for the anchors including consideration of group effects. 2. Maximum unbonded length and minimum bonded length of the tendon. 3. Maximum recommended anchor tension capacity based upon the soil or rock strength/grout bond and anchor depth/spacing. 4. Allowable bond stress at the ground/grout interface and applicable factor of safety for ultimate bond stress. 5. Anchor axial tension stiffness recommendations at the anticipated anchor axial tension displacements, when required for structural analysis. 6. Minimum grout pressure for installation and post-grout pressure. 7. _Class I corrosion protection is required for all permanent and extended temporary anchors in service more than 2 years.

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

    [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.

    2025 CALIFORNIA BUILDING CODE 17A-9

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    �

    SPECIAL INSPECTIONS AND TESTS

    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.

    [DSA-SS, DSA-SS/CC] The minimum requirements for a qualified high-strength bolting special inspector shall be an International Code Council certified Structural Steel and Bolting Special Inspector (S1). Additionally, the requirements in Table 1705A.2.1 of the California Building Code shall apply.

    1705A.2.9 Special inspection and tests of cold-formed steel light-frame construction. [DSA-SS, DSA-SS/CC] Special inspections and tests for cold-formed steel light-frame construction shall be in accordance with quality assurance requirements of AISI S240 and this code. Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    Quality assurance application is not permitted for the following AISI S240, Chapter D Sections: 1. D6.4 (Quality Assurance Inspection Tasks). 2. D6.5 (Coordinated Inspection). 3. D6.7 (Inspection of Welding). 4. D6.8 (Inspection of Mechanical Fastening). 5. D6.9 (Inspection of Cold-Formed Steel Light-Frame Construction). 6. D6.10 (Additional Requirements for Lateral Force-Resisting Systems). 7. D7 (Nonconforming Material and Workmanship).

    Basic frame inspection provisions of AISI S240, Chapter D are not permitted and inspector of record inspections shall be in accor- dance with the California Administrative Code.

    1705 A .3 Concrete construction. Special inspections and tests of concrete construction shall be performed in accordance with this section and Table 1705 A .3.

    Exception: Special inspections and tests shall not be required for concrete patios, driveways and sidewalks, on grade.

  • 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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    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.

  • CBC § 1705A.6 High relevance — show source text
    TABLE 1705A.6—REQUIRED SPECIAL INSPECTIONS AND TESTS OF SOILS Col2 Col3
    TYPE CONTINUOUS
    SPECIAL INSPECTION    		 PERIODIC SPECIAL
    INSPECTION
    1. Verify materials below shallow foundations are adequate to achieve the design bearing capacity. — X
    2. Verify excavations are extended to proper depth and have reached proper material. — X
    3. Perform classification and testing of compacted fill materials. — X
    4. During fill placement, verify use of proper materials and procedures in accordance with the
    provisions of the approved geotechnical report. Verify densities and lift thicknesses during
    placement and compaction of compacted fill.    		 X —
    5. Prior to placement of compacted fill, inspect subgrade and verify that site has been
    prepared properly.    		 — X

    1705A.6.1 Soil fill. All fills used to support the foundations of any building or structure shall be continuously inspected by the geotechnical engineer or his or her qualified representative. It shall be the responsibility of the geotechnical engineer to verify that fills meet the requirements of the approved construction documents and to coordinate all fill inspection and testing during construc- tion involving such fills.

    The duties of the geotechnical engineer or his or her qualified representative shall include, but need not be limited to, the inspec- tion of cleared areas and benches prepared to receive fill; inspection of the removal of all unsuitable soils and other materials; the approval of soils to be used as fill material; the inspection of placement and compaction of fill materials; the testing of the completed fills; and the inspection or review of geotechnical drainage devices, buttress fills or other similar protective measures in accordance with the approved construction documents.

    A verified report shall be submitted by the geotechnical engineer as required by the California Administrative Code. The report shall indicate that all tests and inspections required by the approved construction documents were completed and whether the tested materials and/or inspected work meet the requirements of the approved construction documents.

    1705A.6.2 Earth-retaining shoring. Special inspections and tests of earth-retaining shoring shall be in accordance with applicable portions of Section 1812A.

    1705A.6.3 Vibro stone columns. Special inspections and tests of vibro stone columns for ground improvement shall be in accordance with Section 1813A.5.

    1705 A .7 Driven deep foundations. Special inspections and tests shall be performed during installation of driven deep foundation elements as specified in 1810A.3.3.1.2 and Table 1705 A .7. The approved geotechnical report and the construction documents prepared by the registered design professionals shall be used to determine compliance.

    TABLE 1705A.7—REQUIRED SPECIAL INSPECTIONS AND TESTS OF DRIVEN DEEP FOUNDATION ELEMENTS Col2 Col3
    TYPE CONTINUOUS
    SPECIAL INSPECTION    		 PERIODIC SPECIAL
    INSPECTION
    1. Verify element materials, sizes and lengths comply with the requirements. X —
    2.

Frequently asked questions

Who must perform the continuous special inspection for driven piles?

A qualified representative of the geotechnical engineer responsible for that portion of the work must continuously observe driven pile installation (§1705.7.1) .

If a driven pile’s allowable load is based on a dynamic formula, what specific reporting is required?

The geotechnical representative must report the design formula used and the permanent penetration under the last 10 blows, along with the usual driving records (§1705.7.1) .

Are helical piles tested the same way as driven piles?

No. Helical piles require continuous inspection and recording of installation torque, depth and geometry per §1705.9; load testing or production testing is determined by the geotechnical report and the registered design professional (§1705.9) .

Do drilled shafts require special concrete testing?

Yes — cast‑in‑place deep foundation concrete elements must have the concrete tests and inspections required by §1705.3 in addition to the continuous drilling and placement inspections listed in Table 1705.8 (§1705.8; Table 1705.8) .

Where do I list these special inspections for the permit?

The registered design professional in responsible charge must prepare the Statement of Special Inspections identifying these deep foundation inspections/tests as required by §1704.3 .

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Foundations & Soils — Required Inspections and Testing

California Building Code