CBC · California Building Code

What are the special provisions for existing concrete (core testing, epoxy injection, FRP strengthening)?

The CBC requires representative concrete core sampling (minimum 4‑inch cores and at least three cores per 4,000 ft²) to establish in‑place strength (§1911.1); epoxy crack repairs must follow ACI 548.15 (§1911.2); externally bonded FRP strengthening must follow ACI 440.2R, disallows NSM FRP bars, and requires acceptance/inspection criteria (ICC‑ES AC125/AC178) (§1911.3).

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

The California Building Code requires representative concrete core sampling to establish in-place strength and sets minimum core size and sampling frequency (§1911.1). Crack repair by epoxy injection must conform to ACI 548.15 per §1911.2, and externally bonded FRP strengthening must be designed and constructed in accordance with ACI 440.2R with specified exceptions and acceptance/inspection criteria per §1911.3. These requirements are stated in Section 1911 and its subsections (§1911.1, §1911.2, §1911.3) of the CBC.

Requirements in detail

1) Concrete core sampling — what to take and why

  • Purpose: obtain representative in-place compressive strength and material information as designated by the architect or structural engineer. §1911 (general) and §1911.1 set the sampling requirements.
  • Minimum sampling frequency: at least three cores from each building for each 4,000 ft² (372 m²) of floor area, or fraction thereof. §1911.1.
  • Minimum core diameter: 4 in (102 mm). The enforcement agency may allow smaller cores (2.75 in / 70 mm) where reinforcement is closely spaced and coarse aggregate does not exceed 3/4 in (19 mm). §1911.1.

Markdown table — decision-relevant dimensions/values

Decision variable Required value / threshold Code Reference
Minimum core diameter (typical) 4 in (102 mm) §1911.1 —
Reduced core diameter allowed 2.75 in (70 mm) — only if reinforcement closely spaced and coarse aggregate ≤ 3/4 in (19 mm), and allowed by enforcement agency §1911.1 —
Minimum number of cores ≥ 3 cores per building per each 4,000 ft² (372 m²) or fraction thereof §1911.1 —
Use of core strength for rehab (related) Structural use of existing concrete with core strength < 1,500 psi not permitted in rehabilitation (see related provision) §1911A.1 —

Notes on sampling practice (grounded in §1911.1): cores must be taken at representative locations as designated by the registered design professional; enforcement agency approval is required for reduced-diameter cores.

2) Crack repair by epoxy injection

  • The CBC requires that crack repair by epoxy injection conform to all requirements of ACI 548.15. That is the controlling standard called out in §1911.2.
  • Practical implications: follow ACI 548.15 for crack routing/cleaning, surface preparation, injection procedure, epoxy material properties, acceptance criteria, and testing/verification procedures (ACI details are mandated by the CBC reference). §1911.2.

3) Externally bonded FRP strengthening (Design, construction, inspection)

  • Design/construction standard: FRP strengthening using externally bonded systems must follow ACI 440.2R per §1911.3.
  • Exceptions spelled out in §1911.3:
    • Near-surface mounted (NSM) FRP bars are not permitted. §1911.3.
    • Strengthening shear walls and diaphragms (including chords and collectors) must be considered as an alternative system (i.e., special consideration; not treated the same as local patch strengthening). §1911.3.
  • Acceptance, capacity, reliability and inspection:
    • The code permits design capacities, reliability and serviceability of FRP materials to be established in accordance with ICC‑ES AC125. §1911.3.
    • Minimum inspection requirements for FRP composite systems are to follow ICC‑ES AC178. §1911.3.
  • Practical consequences: submit FRP designs referencing ACI 440.2R and, if using manufacturer or test-based capacities, provide ICC‑ES AC125 evidence (or equivalent approved reports) and plan for inspection per AC178. §1911.3.

4) How the referenced standards are used

  • The CBC text does not repeat the ACI/ICC‑ES technical content; it mandates compliance with those consensus documents. The ACI/ICC‑ES documents contain the technical acceptance, testing and inspection criteria that the code requires you to follow when performing epoxy injections or FRP strengthening. §1911.2 and §1911.3 point to ACI 548.15 and ACI 440.2R; §1911.3 also references ICC‑ES acceptance criteria (AC125, AC178).

Exceptions & special cases

  • Reduced-diameter cores (2.75 in / 70 mm) are allowed only by the enforcement agency and only when reinforcement spacing and coarse-aggregate size meet the specified limits (§1911.1).
  • NSM FRP bars are explicitly prohibited for externally bonded FRP strengthening (§1911.3, Exception 1).
  • Strengthening of shear walls, diaphragms, chords and collectors using externally bonded FRP must be treated as an alternative system and requires special consideration (Exception 2 to §1911.3).
  • The CBC defers the technical acceptance, test and inspection criteria to the referenced standards (ACI 548.15, ACI 440.2R, ICC‑ES AC125/AC178); the code user must consult those documents for detailed test procedures, material qualifications and inspection protocols (§1911.2, §1911.3).

Common mistakes

  • Treating the CBC references (e.g., “follow ACI 440.2R”) as optional; the code requires compliance with the referenced standard for those repairs (§1911.2, §1911.3).
  • Using NSM FRP bars despite the explicit prohibition in §1911.3.
  • Failing to provide the minimum number of cores or taking them from non-representative locations (the RDP should designate locations per §1911.1).
  • Omitting ICC‑ES acceptance/inspection documentation when relying on manufacturer or test-based FRP capacities (the CBC permits establishing capacities via AC125 and requires inspection per AC178). §1911.3.
  • Assuming any core diameter is acceptable—reduced diameters are explicitly conditional and need enforcement agency approval (§1911.1).

Worked example — applying the rule with numbers

Scenario: A 9,000 ft² single-story existing warehouse is being evaluated for rehabilitation and the structural engineer needs to establish in-place concrete strength and plan FRP strengthening of some beams.

  1. Core sampling per §1911.1:
    • Required cores = at least 3 cores per each 4,000 ft² (or fraction). 9,000 ft² → ceil(9,000 / 4,000) = 3 increments → 3 × 3 = 9 cores minimum. §1911.1.
    • Take cores ≥ 4 in diameter (102 mm) unless enforcement agency approves 2.75 in cores and the reinforcement spacing and aggregate size conditions are met. §1911.1.
  2. Crack repairs in beams:
    • If epoxy injection is proposed, the repair procedure, epoxy materials, surface prep and acceptance testing must conform to ACI 548.15 as required by §1911.2. Provide procedure and material data referencing ACI 548.15 in the submittal. §1911.2.
  3. FRP strengthening:
    • Design and detailing of externally bonded FRP for beams must follow ACI 440.2R (§1911.3). Show calculations per ACI 440.2R and, if using manufacturer test data to establish capacities, submit ICC‑ES AC125 evidence or equivalent and plan inspections per AC178. Also ensure NSM FRP is not used (prohibited). §1911.3.

Related provisions

  • §1911.1 — Concrete core sampling details (diameter, sampling frequency).
  • §1911.2 — Crack repair by epoxy injection: requires conformance with ACI 548.15.
  • §1911.3 — Externally bonded FRP strengthening: requires ACI 440.2R; lists exceptions; permits ICC‑ES AC125/AC178 for capacities/inspection.
  • §1911A.1 — Related existing-concrete provision: structural use of existing concrete with core strength less than 1,500 psi is not permitted in rehabilitation work (see related chapter/appendix provisions).
  • Referenced standards called out in these sections (for full technical details): ACI 548.15, ACI 440.2R, ICC‑ES AC125, ICC‑ES AC178.

Code references

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

  • CBC § 1911.1 High relevance — show source text

    SECTION 1911—EXISTING CONCRETE STRUCTURES [OSHPD 1R, 2 & 5]

    1911.1 Concrete Core Sampling. Where concrete cores are required to be taken for material property determination, cores shall be at least 4 inches (102 mm) in diameter. Cores as small as 2.75 inches (70 mm) in diameter may be allowed by the enforcement agency when reinforcement is closely spaced and the coarse aggregate does not exceed [3] / 4 inch (19 mm).

    1911.2 Crack repair by epoxy injection. Crack Repair of concrete and masonry member by epoxy injection shall conform to all require- ments of ACI 548.15.

    1911.3 Concrete strengthening by externally bonded fiber reinforced polymer (FRP). Design and construction of externally bonded FRP systems for strengthening concrete structures shall be in accordance with ACI 440.2R.

    Exceptions: 1. Near-Surface Mounted (NSM) FRP bars shall not be permitted. 2. Strengthening of shear walls and diaphragms (including chords and collectors) shall be considered as an alternative system.

    Design capacities, reliability and serviceability of FRP materials shall be permitted to be established in accordance with ICC-ES AC 125. Minimum inspection requirements of FRP composite systems shall be in accordance with ICC-ES AC 178.

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    CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 19A – CONCRETE

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

  • CBC § 2.75 High relevance — show source text

    CONCRETE

    For existing concrete structures, sufficient cores shall be taken at representative locations throughout the structure, as designated by the architect or structural engineer, so that knowledge will be had of the in-place strength of the concrete. At least three cores shall be taken from each building for each 4,000 square feet (372 m [2] ) of floor area, or fraction thereof. Cores shall be at least 4 inches (102 mm) in diameter. Cores as small as 2.75 inches (70 mm) in diameter may be allowed by the enforcement agency when reinforcement is closely spaced and the coarse aggregate does not exceed [3] / 4 inch (19 mm).

    1911A.2 Crack repair by epoxy injection. Crack repair of concrete and masonry member by epoxy injection shall conform to all require- ments of ACI 548.15.

    1911A.3 Concrete strengthening by externally bonded fiber reinforced polymer (FRP). Design and construction of externally bonded FRP systems for strengthening concrete structures shall be in accordance with ACI 440.2R.

    Exceptions: 1. Near-Surface Mounted (NSM) FRP bars shall not be permitted. 2. Strengthening of shear walls and diaphragms (including chords and collectors) shall be considered as an alternative system.

    Design capacities, reliability, serviceability of FRP materials shall be permitted to be established in accorda nce with ICC-ES AC 125. Minimum inspection requirements of FRP composite systems shall be in accordance with ICC-ES AC 178.

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    CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 20 – ALUMINUM

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

  • CBC § 12.7.3.4 High relevance — show source text

    12.7.3.4 – At least two No. 5 bars in diaphragms having two layers of reinforcement in both directions and one No. 5 bar in diaphragms having a single layer of reinforcement in both directions shall be provided around openings larger than 12 inches in any dimension in addition to the minimum reinforcement required by Section 12.6.

    1910.3.2 ACI 318, Section 18.12.6. Add Section 18.12.6.2 to ACI 318 as follows:

    Collector and boundary elements in topping slabs placed over precast floor and roof elements shall not be less than 3 inches (76 mm) or 6 d b thick, where d b is the diameter of the largest reinforcement in the topping slab.

    1910.3.3 ACI 318, Table 19.2.1.1. Modify ACI 318 Table 19.2.1.1 as follows: For concrete designed and constructed in accordance with this chapter, f ′ c, , shall not be less than 3,000 psi (20.7 MPa). Reinforced normal weight concrete with specified compressive strength higher than 8,000 psi (55 MPa) shall require prior approval of struc- tural design method and acceptance criteria by the enforcement agency.

    1910.3.4 ACI 318, Section 26.11.1.2. Modify ACI 318 Section 26.11.1.2 by adding Item (e) as follows:

    (e) Forms for shotcrete shall be substantial and rigid. Forms shall be built and placed so as to permit the escape of air and rebound. Adequate ground wires, which are to be used as screeds, shall be placed to establish the thickness, surface planes and form of the shotcrete work. All surfaces shall be rodded to these wires.

    SECTION 1911—EXISTING CONCRETE STRUCTURES [OSHPD 1R, 2 & 5]

    1911.1 Concrete Core Sampling. Where concrete cores are required to be taken for material property determination, cores shall be at least 4 inches (102 mm) in diameter. Cores as small as 2.75 inches (70 mm) in diameter may be allowed by the enforcement agency when reinforcement is closely spaced and the coarse aggregate does not exceed [3] / 4 inch (19 mm).

    1911.2 Crack repair by epoxy injection. Crack Repair of concrete and masonry member by epoxy injection shall conform to all require- ments of ACI 548.15.

    1911.3 Concrete strengthening by externally bonded fiber reinforced polymer (FRP). Design and construction of externally bonded FRP systems for strengthening concrete structures shall be in accordance with ACI 440.2R.

    Exceptions: 1. Near-Surface Mounted (NSM) FRP bars shall not be permitted. 2. Strengthening of shear walls and diaphragms (including chords and collectors) shall be considered as an alternative system.

    Design capacities, reliability and serviceability of FRP materials shall be permitted to be established in accordance with ICC-ES AC 125. Minimum inspection requirements of FRP composite systems shall be in accordance with ICC-ES AC 178.

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  • CBC § 1911A.2 High relevance — show source text

    1911A.2 Crack repair by epoxy injection. Crack repair of concrete and masonry member by epoxy injection shall conform to all require- ments of ACI 548.15.

    1911A.3 Concrete strengthening by externally bonded fiber reinforced polymer (FRP). Design and construction of externally bonded FRP systems for strengthening concrete structures shall be in accordance with ACI 440.2R.

    Exceptions: 1. Near-Surface Mounted (NSM) FRP bars shall not be permitted. 2. Strengthening of shear walls and diaphragms (including chords and collectors) shall be considered as an alternative system.

    Design capacities, reliability, serviceability of FRP materials shall be permitted to be established in accorda nce with ICC-ES AC 125. Minimum inspection requirements of FRP composite systems shall be in accordance with ICC-ES AC 178.

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    CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 20 – ALUMINUM

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

    Adopting agency BSC BSC-
    CG    		 SFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC
    Adopting agency BSC BSC-
    CG    		 SFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6
    Adopt entire chapter X X X X X
    Adopt entire chapter as
    amended (amended
    sections listed below)    		 X X X X X X X
    Adopt only those sections
    that are listed below
    Chapter / Section
    2001.1.1 X X X X X X X
    2001.1.2 X X X X X X X
    2001.1.3 X X X X X X X
    _2001.1.
  • CBC § 1910A.5.5 High relevance — show source text

    1910A.5.5 Test acceptance criteria. Proof tests shall satisfy the following minimum requirements. 1. Tension test: Anchors shall be tested in the unconfined condition in accordance with ASTM E3121 except that the minimum clearance to the test frame shall be 1.5 times the anchor’s embedment depth. Test load shall be maintained for a minimum of 15 seconds and shall exhibit no discernible movement during the tension test, e.g., as evidenced by loosening of the washer under the nut or an abrupt decrease in the gauge pressure.

    Exception: Adhesive anchors shall be permitted to be tested in confined conditions in accordance with ASTM E3121 when the approved construction documents indicate that concrete breakout does not control the design tensile strength. 2. Torque test: Torque-controlled post-installed anchors tested with a calibrated torque wrench shall attain the specified torque within [1] / 2 turn of the nut; or one-quarter ( [ 1] / 4 ) turn of the nut for a [3] / 8 inch sleeve anchor only. Screw-type anchors tested with a calibrated torque wrench shall attain the specified torque within one-quarter ( [ 1] / 4 ) turn of the screw after initial seating of the screw head.

    SECTION 1911A—EXISTING CONCRETE STRUCTURES

    1911A.1 Existing concrete structures.

    The structural use of existing concrete with a core strength less than 1,500 psi (10.3MPa) is not permitted in rehabilitation work.

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    CONCRETE

    For existing concrete structures, sufficient cores shall be taken at representative locations throughout the structure, as designated by the architect or structural engineer, so that knowledge will be had of the in-place strength of the concrete. At least three cores shall be taken from each building for each 4,000 square feet (372 m [2] ) of floor area, or fraction thereof. Cores shall be at least 4 inches (102 mm) in diameter. Cores as small as 2.75 inches (70 mm) in diameter may be allowed by the enforcement agency when reinforcement is closely spaced and the coarse aggregate does not exceed [3] / 4 inch (19 mm).

    1911A.2 Crack repair by epoxy injection. Crack repair of concrete and masonry member by epoxy injection shall conform to all require- ments of ACI 548.15.

    1911A.3 Concrete strengthening by externally bonded fiber reinforced polymer (FRP). Design and construction of externally bonded FRP systems for strengthening concrete structures shall be in accordance with ACI 440.2R.

    Exceptions: 1. Near-Surface Mounted (NSM) FRP bars shall not be permitted. 2. Strengthening of shear walls and diaphragms (including chords and collectors) shall be considered as an alternative system.

    Design capacities, reliability, serviceability of FRP materials shall be permitted to be established in accorda nce with ICC-ES AC 125. Minimum inspection requirements of FRP composite systems shall be in accordance with ICC-ES AC 178.

    2025 CALIFORNIA BUILDING CODE 19A-11

  • CBC § 1911.2 High relevance — show source text

    1911.2 Crack repair by epoxy injection. Crack Repair of concrete and masonry member by epoxy injection shall conform to all require- ments of ACI 548.15.

    1911.3 Concrete strengthening by externally bonded fiber reinforced polymer (FRP). Design and construction of externally bonded FRP systems for strengthening concrete structures shall be in accordance with ACI 440.2R.

    Exceptions: 1. Near-Surface Mounted (NSM) FRP bars shall not be permitted. 2. Strengthening of shear walls and diaphragms (including chords and collectors) shall be considered as an alternative system.

    Design capacities, reliability and serviceability of FRP materials shall be permitted to be established in accordance with ICC-ES AC 125. Minimum inspection requirements of FRP composite systems shall be in accordance with ICC-ES AC 178.

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    CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 19A – CONCRETE

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

    Adopting agency BSC BSC-
    CG    		 SFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC
    Adopting agency BSC BSC-
    CG    		 SFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6
    Adopt entire chapter X X X
    Adopt entire chapter as
    amended (amended
    sections listed below)
    Adopt only those sections
    that are listed below
    Chapter / Section
    1905A.3_ –_1905A3.1 † †

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

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    19A-2 2025 CALIFORNIA BUILDING CODE

  • CBC § 355.2 High relevance — show source text

    355.2—22: Qualification of Post-Installed Mechanical Anchors in Concrete and Commentary

    1617A.1.19, 1901.3.2

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    • [>]

    REFERENCED STANDARDS

    355.4—19(21): Qualification of Post-Installed Adhesive Anchors in Concrete and Commentary

    1617A.1.19, 1901.3.3

    440.2R—17: Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures

    1911.3, 1911A.3

    440.11—22: Structural Concrete Buildings Reinforced Internally with Fiber Reinforced Polymer (FRP) Bars – Code Requirements

    1901.2.1

    506R—16: Guide to Shotcrete

    1908.1, 1908A.1

    506.2—13 (18): Specification for Shotcrete

    1705A.3.9, 1908.1, 1908A.1, 1909.4

    506.4R—19: Guide for the Evaluation of Shotcrete

    1908.1, 1908A.1, 1909.4

    506.6T—17: Visual Shotcrete Core Quality Evaluation

    1908.1, 1908A.1, 1909.4

    548.15-20: Specification for Crack Repair by Epoxy Injection

    1911.2, 1911A.2

    550.5—18: Code Requirements for the Design of Precast Concrete Diaphragms for Earthquake Motions

    Table 1705.3

    ITG—7-09: Specification for Tolerances for Precast Concrete

    1901.7.2

    AISC American Institute of Steel, 130 East Randolph Street, Suite 2000, Chicago, IL 60601-6219

    ANSI/AISC 341—22: Seismic Provisions for Structural Steel Buildings 1705.13.1.1, 1705.13.1.2, 1705.14.1.1, 1705.14.1.2, Table 1705A.2.1, 1810.3.5.3.1, 2202.2.1.1, 2202.2.1.2, 2202.2.2, 2202A.5, 2205.3,

    2215.2

    ANSI/AISC 358—22: Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications Table 1705A.2.1, 2202.2.1, 2202.2.1.2, 2202.3, 2202A.3, 2202A.6, 2215.3, 2205A, 2205.4, 2206A.2, 2206.2.1

  • California Building Code High relevance — show source text


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    4

  • CBC § A301 Medium relevance — show source text

    SECTION A301—GENERAL

    [BS] A301.1 Purpose. The provisions of this chapter are intended to promote public safety and welfare by reducing the risk of earthquake-induced damage to existing wood-frame residential buildings. The requirements contained in this chapter are prescriptive minimum standards intended to improve the seismic performance of residential buildings; however, they will not necessarily prevent earthquake damage.

    This chapter sets standards for strengthening that may be approved by the code official without requiring plans or calculations prepared by a registered design professional. The provisions of this chapter are not intended to prevent the use of any material or method of construction not prescribed herein. The code official may require that construction documents for strengthening using alternative materials or methods be prepared by a registered design professional.

    [BS] A301.2 Scope. The provisions of this chapter apply to residential buildings of light-frame wood construction containing one or more of the structural weaknesses specified in Section A303.

    Exception: The provisions of this chapter do not apply to the buildings, or elements thereof, listed as follows. These buildings or elements require analysis by a registered design professional in accordance with Section A301.3 to determine appropriate strengthening:

    1. Group R-1.
    2. Group R with more than four dwelling units.
    3. Buildings with a lateral force-resisting system using poles or columns embedded in the ground.
    4. Cripple walls that exceed 4 feet (1219 mm) in height.
    5. Buildings exceeding three stories in height and any three-story building with cripple wall studs exceeding 14 inches (356 mm) in height.
    6. Buildings where the code official determines that conditions exist that are beyond the scope of the prescriptive requirements of this chapter.
    7. Buildings or portions thereof constructed on concrete slabs on grade.

    [BS] A301.3 Alternative design procedures. The details and prescriptive provisions herein are not intended to be the only acceptable strengthening methods permitted. Alternative details and methods shall be permitted to be used where approved by the code official. Approval of alternatives shall be based on a demonstration that the method or material used is at least equivalent in terms of strength, deflection and capacity to that provided by the prescriptive methods and materials.

    Where analysis by a registered design professional is required, such analysis shall be in accordance with all requirements of the building code, except that the seismic forces may be taken as 75 percent of those specified in the California Building Code .

    SECTION A302—DEFINITIONS

    [BS] A302.1 Definitions. For the purpose of this chapter, in addition to the applicable definitions in the building code, certain additional terms are defined as follows:

    [BS] ADHESIVE ANCHOR. An assembly consisting of a threaded rod, washer, nut, and chemical adhesive approved by the code official for installation in existing concrete or masonry.

    CODE OFFICIAL. “Code Official” shall have the same meaning as Enforcing Agency.

    [BS] CRIPPLE WALL. A wood-frame stud wall extending from the top of the foundation to the underside of the lowest floor framing.

    ENFORCING AGENCY. The designated department or agency as specified by statute or regulation.

    [BS] EXPANSION ANCHOR. An approved post-installed anchor, inserted into a predrilled hole in existing concrete or masonry, that transfers loads to or from the concrete or masonry by direct bearing or friction or both.

    [BS] PERIMETER FOUNDATION. A foundation system that is located under the exterior walls of a building.

  • CBC § 18941.8. Medium relevance — show source text

    — Enforcing agency State or local agency specified by the applicable provisions of law.

    — Authority cited Health and Safety Code Section 18941.8.

    Reference — Health and Safety Code Section 18941.8.

    1.2.2.1 Adopting agency identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym BSC-CG .

    1.2.3 Alternative materials, design and methods of construction and equipment. The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code,

    1-6 2025 CALIFORNIA BUILDING CODE

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

    ADMINISTRATION

    provided that any such alternative has been approved. An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety.

    1.2.3.1 Research reports. Supporting data, where necessary to assist in the approval of materials or assemblies not specifically provided for in this code, shall consist of valid research reports from approved sources.

    1.2.3.2 Tests. Whenever there is insufficient evidence of compliance with the provisions of this code, or evidence that a material or method does not conform to the requirements of this code, or in order to substantiate claims for alternative materials or methods, the building official shall have the authority to require tests as evidence of compliance to be made at no expense to the jurisdiction. Test methods shall be as specified in this code or by other recognized test standards. In the absence of recognized and accepted test meth- ods, the building official shall approve the testing procedures. Tests shall be performed by an approved agency. Reports of such tests shall be retained by the building official for the period required for retention of public records.

    SECTION 1.3—BOARD OF STATE AND COMMUNITY CORRECTIONS

    1.3.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

    Application— Local detention facilities.

    Enforcing agency— Board of State and Community Corrections.

    Authority cited— Penal Code Section 6030; Welfare and Institutions Code Sections 207.1, 210 and 885.

    Reference— Penal Code Section 6030; Welfare and Institutions Code Sections 207.1, 210 and 885.

    1.3.2 Adopting agency identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym BSCC.

    SECTION 1.4—DEPARTMENT OF CONSUMER AFFAIRS

  • CBC § 18934.7. Medium relevance — show source text

    ADMINISTRATION

    2. University of California, California State Universities and California Community Colleges.

    Application— Standards for lighting for parking lots and primary campus walkways at the University of California, California State Universities and California Community Colleges.

    Enforcing agency— State or local agency specified by the applicable provisions of law.

    Authority cited— Government Code Section 14617.

    Reference— Government Code Section 14617.

    3. Existing state-owned buildings, including those owned by the University of California and by the California State University.

    Application— Building seismic retrofit standards including abating falling hazards of structural and nonstructural components and strengthening of building structures. See also Division of the State Architect.

    Enforcing agency— State or local agency specified by the applicable provisions of law.

    Authority cited— Health and Safety Code Section 16600.

    Reference— Health and Safety Code Sections 16600 through 16604. 4. Unreinforced masonry-bearing wall buildings.

    Application— Minimum seismic strengthening standards for buildings specified in Appendix Chapter A1 of the California Existing Building Code, except for buildings subject to building standards pursuant to Health and Safety Code (commencing) with Section 17910.

    Enforcing agency— State or local agency specified the applicable provisions of law.

    Authority cited— Health and Safety Code Section 18934.7.

    Reference— Health and Safety Code, Division 13, Part 2.5, commencing with Section 18901.

    1.2.1.1 State building. For purposes of this code, a “state building” is a structure for which a state agency or state entity has authority to construct, alter, enlarge, replace, repair or demolish.

    1.2.1.2 Enforcement. [CSU, UC, Judicial Council and California Department of Corrections and Rehabilitation] State agencies or state entities authorized to construct state buildings may appoint a building official who is responsible to the agency for enforcement of the provisions of the California Building Standards Code.

    Exception: State buildings regulated by other sections of this code remain the enforcement responsibility of the designated entities.

    1.2.1.3 Enforcement. Reserved for DGS.

    1.2.1.4 Adopting agency identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym BSC .

    1.2.2 BSC-CG. Specific scope of application of the agency responsible for enforcement, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated. 1. Green building standards for nonresidential occupancies.

    Application— All occupancies where no state agency has the authority to adopt green building standards applicable to those occupancies.

    Enforcing agency— State or local agency specified by the applicable provisions of law.

    Authority cited— Health and Safety Code Sections 18930.5(a), 18938 and 18940.5.

  • CBC § 14.3 Medium relevance — show source text

    ICC-ES AC 156—24: Acceptance Criteria for Seismic Certification by Shake-Table Testing of Nonstructural Components*

    1705A.14.3

    ICC-ES AC 178—24: : Acceptance Criteria for Inspection and Verification of Concrete, and Reinforced and Unreinforced Masonry* Strengthening Using Fiber-Reinforced Polymer (FRP) Composite Systems

    1911A.3, 1911.3

    ICC-ES AC 193—24: Acceptance Criteria for Mechanical Anchors in Concrete Elements*

    1617A.1.19, 1901.3.2

    ICC-ES AC 232—24: Acceptance Criteria for Anchor Channels in Concrete Elements*

    1617A.1.19, 1901.3.2

    ICC-ES AC 308—24: Acceptance Criteria for Post-Installed Adhesive Anchors in Concrete Elements*

    1617A.1.19, 1901.3.3

    ICC-ES AC 331: Acceptance Criteria for Smoke and Heat Vents

    910.3.1

    ICC-ES AC 358—24: Acceptance Criteria for Helical Foundation Systems and Devices*

    1810A.3.1.5.1, 1810.3.1.5.1

    ICC-ES AC 446—24: Acceptance Criteria for Headed Cast-in Specialty Inserts in Concrete*

    1617A.1.19, 1901.3.2

    ICC 1100—2019: Standard for Spray-applied Foam Plastic Insulation

    2603.1.1

    ICC/MBI 1200—2021: [OSHPD 1, 1R, 2, 4, and 5] Standard for Off-Site Construction: Planning, Design, Fabrication and Assembly

    1710, 1710A

    ICC/MBI 1205—2021: [OSHPD 1, 1R, 2, 4, and 5] Standard for Off-Site Construction: Inspection and Regulatory Compliance

    1710, 1710A

    SSTD 11—97: 1997 SBCCI Test Standard for Determining Wind Resistance of Concrete or Clay Roof Tiles

    1504.3.1.1, 1504.3.1.2, 1504.3.1.3

    * Refers to International Building Code, 2024 as a referenced standard.

    ISO International Organization for Standardization, Chemin de Blandonnet 8 CP 401 1214 Vernier, Geneva, Switzerland

    ISO 668—2013: Series 1 Freight Containers—Classifications, Dimensions and Ratings

    Table 3114.8.5.3

    ISO 1496-1—2013: Series 1 Freight Containers—Specification and Testing - Part 1: General Cargo Containers for General Purposes 3114.8, Table 3114.8.5.3

    ISO 6346—1995: Freight Containers—Coding, Identification and Marking with Amendment 3—2012

    3114.3

    ISO 8115—86: Cotton Bales—Dimensions and Density Table 307.1(1), Table 415.11.1.1

Frequently asked questions

Do the CBC provisions tell me exactly how to perform an epoxy injection?

No — the CBC requires that epoxy injection work conform to ACI 548.15; you must follow that standard’s procedures, materials and acceptance criteria as cited by §1911.2.

Can I use near‑surface‑mounted (NSM) FRP bars to strengthen concrete elements?

No. §1911.3 explicitly prohibits Near‑Surface Mounted (NSM) FRP bars for externally bonded FRP systems.

How many cores must I take from a 3,200 ft² building?

At least three cores (3,200 ft² is a “fraction thereof” of 4,000 ft², so the minimum three cores per building per 4,000 ft² or fraction applies). §1911.1.

If the core compressive strength tests show very low strength, can I still use the concrete?

The CBC (related provision §1911A.1) indicates structural use of existing concrete with core strength less than 1,500 psi is not permitted in rehabilitation work; consult the enforcing agency and the registered design professional for next steps.

Do I have to provide ICC‑ES reports for FRP materials?

If you are establishing design capacities or relying on manufacturer data, the CBC permits using ICC‑ES AC125 for capacities and requires inspection per AC178; providing accepted evidence (reports) will be necessary for plan approval and inspection acceptance (§1911.3).

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