CBC · California Building Code

Quality assurance: compressive strength verification, mortar/grout sampling and core testing

The CBC requires a documented masonry quality‑assurance program: verify compression strength by the prism test where required, sample mortar at the job start (three successive days, then weekly) and grout each day placed and at least every 5,000 ft2, and take/handle cores and shear test them per the code timing and acceptance rules; community‑college projects have supplemental documentation requirements.

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Last reviewed: July 5, 2026

What the code requires — 2-4 sentences

The CBC requires a documented quality‑assurance program for masonry that follows the inspection and testing requirements of Chapter 17 and TMS 602; the program must include verification of masonry compressive strength, mortar and grout sampling/testing, and (where required) masonry core testing (§ 2105.1, § 2105.2, § 2105.3). Verification of specified masonry compressive strength during construction (and before construction when required) is to be provided using the prism test method per TMS 602, Article 1.4 B.3 (§ 2105.2). For community‑college (DSA‑SS/CC) projects, additional/more prescriptive mortar and grout sampling/testing requirements are added at § 2115.4.1.

Requirements in detail

1) General quality‑assurance framework

  • A QA program must be used to ensure constructed masonry conforms to the approved construction documents and must comply with Chapter 17 inspection/testing and TMS 602 procedures (§ 2105.1).

2) Compressive‑strength verification (f′m)

  • Testing of masonry is required in accordance with TMS 602, Article 1.4 B. The architect or structural engineer must establish a method of quality control acceptable to the enforcement agency and include it in the contract documents. Verification during construction (and prior to start of construction where required) shall be by the prism test method per TMS 602, Article 1.4 B.3 (§ 2105.2).
  • Special requirement: when specified f′m values greater than 2,000 psi are used for reinforced grouted multi‑wythe masonry or reinforced hollow‑unit masonry, those values must be supported by prism test results submitted to the enforcement agency (prism tests per TMS 602, Article 1.4 B.3) (§ 2105.2).

3) Mortar and grout sampling and testing (general projects)

  • Mortar:
    • At the beginning of masonry work take at least one mortar test sample on three successive working days, then at least at one‑week intervals thereafter. Where mortar is proportion‑specified, sampling/testing during construction shall follow ASTM C780 (including Annex 4) to verify proportions in ASTM C270, Table 2. Where property‑specified, mortar shall be laboratory‑prepared/tested per ASTM C780 to verify the properties in ASTM C270, Table 1 and field sampled/tested during construction per ASTM C780 to verify proportions with the lab results. Preblended mortars conforming to ASTM C1714 with material certificate may be exempt from sampling/testing (§ 2105.3).
  • Grout:
    • Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet (465 m2) of masonry wall area. Grout shall meet the minimum strength requirement given in ASTM C476 / TMS 602 Section 2.2 or greater as specified (§ 2105.3).
  • Test specimens and standards:
    • Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. If the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in § 2105.3 are not required (§ 2105.3).

4) Mortar and grout sampling/testing for community‑college projects (DSA‑SS/CC)

  • Section 2115.4.1 modifies TMS 602 Article 1.4 B and adds the same basic requirements as § 2105.3 but with additional documentation requirements for preblended mortars (material certificates, delivery tickets, project inspector/DSA certified masonry inspector and laboratory of record documentation) and reiterates that grout sampling is per mix design, each day placed, and not less than every 5,000 ft2. Test specimen standards are the same (ASTM C780/C1586 and ASTM C1019), and prism tests (TMS 602 Article 1.4 B.3) likewise exempt the other tests when used (§ 2115.4.1).

5) Masonry core testing — frequency and minimum requirements

(These core provisions are stated in the masonry quality‑assurance provisions and in the community‑college supplemental requirements.)

  • Frequency: Two cores shall be taken from each building for each 5,000 square feet (465 m2) of masonry wall area or fraction thereof; the approved agency shall perform or observe coring and sample locations are subject to approval by the registered design professional (see § 2105.4 and § 2115.4.2).
  • Minimum core requirements and handling:
    • Do not core sooner than 7 days after grouting of the selected area.
    • Core diameter: minimum nominal 3 3/4 inches (nominally shown as 3 3/4 in; some places show 3 3/4 or 3‑3/4 in) — the code expresses a minimum 3 3/4‑in nominal diameter for cores.
    • Cores must be taken to avoid unit webs, mortar joints or reinforcing steel; if cells are fully reinforced alternate locations or other means to detect voids/delamination must be used and approved. Core samples must not be soaked before testing and must be stored in sealed plastic bags or non‑absorbent containers immediately after coring and for at least 5 days prior to testing. Visual examination by an approved agency is required and reporting of results/location is required (§ 2105.4 / § 2115.4.2).
  • Shear testing:
    • Shear tests of both joints between the grout core and the outside wythes or face shell shall be made 28 days after grouting of the sample area using a shear test apparatus acceptable to the enforcement agency.
    • Acceptance criterion: the average unit shear value for each pair of cores (four shear tests) from each 5,000 ft2 (or less) on the core cross section shall not be less than 2.5 sqrt(f′m) psi (i.e., 2.5 × √(f′m)) (§ 2105.4 / § 2115.4.2).

Decision‑relevant dimensions and values

Item Value / Frequency Code Reference
Mortar initial sampling One sample on 3 successive working days at start of work, then at least weekly § 2105.3
Mortar standard ASTM C780 (including Annex 4), ASTM C270 tables; preblended ASTM C1714 may be exempt with certificate § 2105.3; § 2115.4.1
Grout sampling frequency For each mix design, each day grout is placed, and not less than every 5,000 ft2 (465 m2) § 2105.3; § 2115.4.1
Grout strength standard Minimum per ASTM C476 / TMS 602 Section 2.2 (or greater as specified) § 2105.3
Compressive‑strength verification method Prism test per TMS 602, Article 1.4 B.3 (during and/or prior to construction as required) § 2105.2
Core sampling frequency Two cores per building for each 5,000 ft2 (465 m2) of wall area (or fraction) § 2105.4; § 2115.4.2
Minimum core diameter Nominal 3 3/4 in (minimum) § 2105.4 / § 2115.4.2
Core waiting & test timing Do not core sooner than 7 days after grouting; shear tests 28 days after grouting; store cores sealed for ≥5 days before testing; do not soak § 2105.4 / § 2115.4.2
Core shear acceptance Average unit shear ≥ 2.5 × √(f′m) psi for each pair of cores (4 shear tests) § 2105.4 / § 2115.4.2

(Where the project is a community‑college (DSA‑SS/CC) project, see § 2115.4.1 for the supplemental/more prescriptive testing and documentation requirements.)

Exceptions & special cases

  • Prism tests substitute for the routine mortar/grout tests: When the prism test method per TMS 602, Article 1.4 B.3 is used during construction, the mortar/grout specimen tests required by § 2105.3 / § 2115.4.1 are not required.
  • Small, nonbearing, nonshear walls: Mortar sampling/testing can be limited to the initial samples at the start of masonry work for each mix design where walls are nonbearing, nonshear and do not exceed 12 ft total height above foundation (exception in § 2105.3).
  • Core‑sampling exception: Core sampling/testing is not required for certain nonbearing single‑wythe hollow concrete unit walls ≤12 ft high designed with f′m ≤ 2,000 psi (see exceptions in the core provisions); also, approved nondestructive methods (e.g., infrared thermography) may be accepted as alternatives where allowed by the authority having jurisdiction (§ 2105.4 / § 2115.4.2).

If a provision or value you expect (for example, an alternate core diameter or a different acceptance formula) is not stated in the code excerpts available to me, I have not invented it — consult the enforcement agency and the full TMS 602 text or CBC if you need additional detail beyond what the cited sections provide.

Common mistakes

  • Treating preblended mortars as automatically exempt — preblended mortars need a compliant ASTM C1714 certificate and supporting documentation for DSA projects (§ 2115.4.1).
  • Skipping the three successive‑day mortar samples at startup or failing to continue weekly sampling thereafter where required (§ 2105.3).
  • Failing to sample grout each day it’s placed or not meeting the “not less than every 5,000 ft2” minimum frequency (§ 2105.3 / § 2115.4.1).
  • Coring too soon (less than 7 days after grouting) or soaking cores before testing — both prohibited by the code procedures for core testing (§ 2105.4 / § 2115.4.2).
  • Including webs, mortar joints or reinforcing steel in the core cross section when sampling (cores must exclude those elements) or not documenting core locations and results properly (§ 2105.4 / § 2115.4.2).
  • Relying on single‑cylinder results or nonstandard specimen preparation when the CBC directs ASTM C780/C1586 and ASTM C1019 specimen procedures (§ 2105.3 / § 2115.4.1).

Worked example — applying the rule with numbers

Scenario: A building with 12,000 ft2 of masonry wall area (single building), using a grout mix design G1 and mortar mix design M1.

  1. Mortar sampling:
    • At start of masonry work: take one mortar sample on each of 3 successive working days (3 samples total). Thereafter, take mortar samples at least once per week for M1 (§ 2105.3).
  2. Grout sampling:
    • For mix G1, grout is placed on 4 different days during construction. For each day grout is placed take at least one sample (so a minimum of 4 samples). Also because the wall area is 12,000 ft2, the CBC minimum of one sample per 5,000 ft2 requires at least ceil(12,000/5,000) = 3 samples; because samples are required each day grout is placed, you will likely have at least 4 samples — both requirements must be met (§ 2105.3).
  3. Core sampling:
    • Two cores are required for each 5,000 ft2 (or fraction). 12,000 ft2 → ceil(12,000/5,000) = 3 increments → 2 cores × 3 = 6 cores total for the building. Cores must be taken no sooner than 7 days after grouting of the selected area, be nominally ≥ 3 3/4 in diameter, be stored sealed for at least 5 days and tested with shear tests at 28 days after grouting. Report locations and results per the approved agency requirements (§ 2105.4 / § 2115.4.2).
  4. Compressive strength verification:
    • If the engineer specified f′m > 2,000 psi for reinforced grouted multi‑wythe masonry, the engineer must submit prism test results demonstrating the ability to meet the higher strength; during construction verification must use prism tests per TMS 602 Article 1.4 B.3 (§ 2105.2). If the project instead uses prism tests during construction, the routine mortar/grout specimen testing requirements may be omitted per the same provisions (§ 2105.3).

Related provisions

  • § 2105.1 — General quality‑assurance program requirements (inspection/testing, TMS 602)
  • § 2105.2 — Compressive strength verification; prism‑test requirement and special rules for f′m > 2,000 psi
  • § 2105.3 — Mortar and grout sampling/testing, specimen standards (ASTM C780/C1586, ASTM C1019) and exceptions
  • § 2105.4 / § 2115.4.2 — Masonry core testing frequency, core size, handling, shear testing and acceptance (see community college supplement)
  • § 2115.4.1 — Community college (DSA‑SS/CC) supplemental requirements for mortar and grout tests and documentation (preblended mortar certificates, inspector/lab documentation)

Code references

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

  • CBC § 1.4 High relevance — show source text

    The architect or structural engineer shall establish a method of quality control of the masonry construction acceptable to the enforcement agency which shall be described in the contract documents. Verification of compliance with the requirements for the specified strength of masonry during construction shall be provided using the prism test method in accordance with TMS 602, Article 1.4 B.3. Verification of compliance with the specified compressive strength prior to the start of construction shall be obtained by using the prism test method in accordance with TMS 602, Article 1.4 B.3.

    2105.3 Mortar and grout tests. [OSHPD 1R, 2 & 5] TMS 602, Article 1.4 B Compressive strength determination. Modify TMS 602, Arti- cle 1.4 B as follows by adding:

    5. Additional testing requirements: a. At the beginning of all masonry work, at least one test sample of the mortar shall be taken on 3 successive working days and at 1-week intervals thereafter. Where mortar is based on a proportion specification, mortar shall be sampled and tested during construction in accordance with ASTM C780, including Annex 4, to verify the proportions specified in ASTM C270, Table 2. Where mortar is based on a property specification, mortar shall be laboratory prepared and tested prior to construction in accordance with ASTM C780 to verify the properties specified in ASTM C270, Table 1 and field sampled and tested during construction in accordance with ASTM C780 to verify the proportions with the laboratory tests. Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 with a material certificate. b. Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet (464.5 m [2] ) of masonry wall area. They shall meet the minimum strength requirement given in ASTM C476/TMS 602 Section 2.2 or greater as specified. c. Additional samples shall be taken whenever any change in materials or job conditions occur, as determined by the building official.

    d. Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. When the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in this section are not required.

    Exception: For nonbearing nonshear masonry walls not exceeding total wall height of 12 feet (3658 mm) above top of foundation, mortar test shall be permitted to be limited to those at the beginning of masonry work for each mix design. 2105.4 Masonry core testing . [OSHPD 1R, 2 & 5] Two cores shall be taken from each building for each 5,000 square feet (465 m [2] ) of the masonry wall area or fraction thereof. The approved agency shall perform or observe the coring of the masonry walls and sample loca- tions shall be subject to approval of the registered design professional.

  • CBC § 2115.3.2.7 High relevance — show source text

    2115.3.2.7 Reinforced hollow unit masonry.

    2115.3.2.7.1 TMS 602, Article 3.5 B Confinement. Add the following to TMS 602, Article 3.5 B: 2. All cells shall be solidly filled with grout in reinforced hollow unit masonry.

    Exception: Reinforced hollow unit masonry laid in running bond used for freestanding site walls or interior nonbearing non-shear wall partitions may be grouted only in cells containing vertical and horizontal reinforcement.

    2115.4 Quality assurance.

    2115.4.1 Mortar and grout tests. TMS 602, Article 1.4 B Compressive Strength Determination. Modify TMS 602, Article 1.4 B as follows by adding: 5. Additional testing requirements: a. At the beginning of all masonry work, at least one test sample of the mortar shall be taken on three successive working days and at least at one-week intervals thereafter. Where mortar is based on a proportion specification, mortar shall be sampled and tested during construction in accordance with ASTM C780, including Annex 4, to verify the proportions spec- ified in ASTM C270, Table 2. Where mortar is based on a property specification, mortar shall be laboratory prepared and tested prior to construction in accordance with ASTM C780 to verify the properties specified in ASTM C270, Table 1 and field sampled and tested during construction in accordance with ASTM C780 to verify the proportions with the laboratory tests. Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 and must be accompanied by corresponding certificates of compliance with current test reports, material certificates and delivery ticket. Documents shall be provided to the project inspector, DSA certified masonry inspector and laboratory of record. b. Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet of masonry wall area. The grout shall meet the minimum strength requirement given in ASTM C476/TMS 602 Section 2.2, or greater as specified. c. Additional samples shall be taken whenever any change in materials or job conditions occur, as determined by the build- ing official.

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    d. Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. When the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in this section are not required. Exception: For nonbearing nonshear masonry walls not exceeding total wall height of 12 feet above the top of the foun- dation, mortar test shall be permitted to be limited to those at the beginning of masonry work for each mix design. 2115.4.2 Masonry core testing. Two cores shall be taken from each building for each 5,000 square feet (465 m [2] ) of the masonry wall area or fraction thereof. The approved agency shall perform or observe the coring of the masonry walls and sample locations shall be subject to approval of the registered design professional.

  • CBC § 2105A.3 High relevance — show source text

    2105A.3 Mortar and grout tests. TMS 602, Article 1.4 B Compressive Strength Determination. Modify TMS 602, Article 1.4 B as follows by adding:

    5. Additional testing requirements: a. At the beginning of all masonry work, at least one test sample of the mortar shall be taken on 3 successive working days and at least at 1-week intervals thereafter. Where mortar is based on a proportion specification, mortar shall be sampled and tested during construction in accordance with ASTM C780, including Annex 4, to verify the proportions specified in ASTM C270, Table 2. Where mortar is based on a property specification, mortar shall be laboratory prepared and tested prior to construction in accordance with ASTM C780 to verify the properties specified in ASTM C270, Table 1 and field sampled and tested during construction in accordance with ASTM C780 to verify the proportions with the laboratory tests. [DSA-SS] Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 and must be accompanied by corresponding certificates of compliance with current test reports, material certificates and delivery ticket. Documents shall be provided to the project inspector, DSA certified masonry inspector and laboratory of record. [OSHPD 1 & 4] Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 with a material certificate.

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    b. Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet of masonry wall area. They shall meet the minimum strength requirement given in ASTM C476/TMS 602, Section 2.2, or greater as specified. c. Additional samples shall be taken whenever any change in materials or job conditions occur, as determined by the building official.

    d. Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. When the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in this section are not required.

    Exception: For nonbearing non-shear masonry walls not exceeding total wall height of 12 feet above top of foundation, mortar tests shall be permitted to be limited to those at the beginning of masonry work for each mix design. 2105A.4 Masonry core testing. Two cores shall be taken from each building for each 5,000 square feet (465 m [2] ) of the masonry wall area or fraction thereof. The approved agency shall perform or observe the coring of the masonry walls and sample locations shall be subject to approval of the registered design professional.

  • CBC § 12.7 High relevance — show source text

    MASONRY

    inch (12.7 mm) below the mortar joint. Horizontal reinforcement shall be placed in bond beam units with a minimum grout cover of 1 inch (25.4 mm) above reinforcing steel for each grout pour.

    2104.3 Aluminum equipment. [OSHPD 1R, 2 & 5] Grout shall not be handled nor pumped utilizing aluminum equipment unless it can be demonstrated with the materials and equipment to be used that there will be no deleterious effect on the strength of the grout.

    SECTION 2105—QUALITY ASSURANCE

    2105.1 General. A quality assurance program shall be used to ensure that the constructed masonry is in compliance with the approved construction documents.

    The quality assurance program shall comply with the inspection and testing requirements of Chapter 17 and TMS 602. 2105.2 Compressive strength , f ′ m . [OSHPD 1R, 2 & 5] Testing of masonry shall be provided in accordance with TMS 602, Article 1.4 B.

    Exception: Where values of f ′ m greater than 2,000 psi (13.79 MPa) are used in the design of reinforced grouted multi-wythe masonry and reinforced hollow unit masonry, they shall be based on prism test results in accordance with TMS 602, Article 1.4 B.3 submitted by the architect or engineer to the enforcement agency which demonstrate the ability of the proposed construction to meet prescribed performance criteria for strength exceed 3,000 psi (20.7 MPa).

    The architect or structural engineer shall establish a method of quality control of the masonry construction acceptable to the enforcement agency which shall be described in the contract documents. Verification of compliance with the requirements for the specified strength of masonry during construction shall be provided using the prism test method in accordance with TMS 602, Article 1.4 B.3. Verification of compliance with the specified compressive strength prior to the start of construction shall be obtained by using the prism test method in accordance with TMS 602, Article 1.4 B.3.

    2105.3 Mortar and grout tests. [OSHPD 1R, 2 & 5] TMS 602, Article 1.4 B Compressive strength determination. Modify TMS 602, Arti- cle 1.4 B as follows by adding:

    5. Additional testing requirements: a. At the beginning of all masonry work, at least one test sample of the mortar shall be taken on 3 successive working days and at 1-week intervals thereafter. Where mortar is based on a proportion specification, mortar shall be sampled and tested during construction in accordance with ASTM C780, including Annex 4, to verify the proportions specified in ASTM C270, Table 2. Where mortar is based on a property specification, mortar shall be laboratory prepared and tested prior to construction in accordance with ASTM C780 to verify the properties specified in ASTM C270, Table 1 and field sampled and tested during construction in _accordance with ASTM C780 to verify the proportions with the laboratory tests.

  • CBC § 2105A.2 High relevance — show source text

    SECTION 2105 A —QUALITY ASSURANCE

    2105 A .1 General. A quality assurance program shall be used to ensure that the constructed masonry is in compliance with the approved construction documents.

    The quality assurance program shall comply with the inspection and testing requirements of Chapter 17 A and TMS 602 and Sections 2105A.2 through 2105A.4.

    2105A.2 Compressive strength, f ′ m . Testing of masonry shall be provided in accordance with TMS 602, Article 1.4 B.

    Exception: Where values of f ′ m greater than 2000 psi (13.79 MPa) are used in the design of reinforced grouted multi-wythe masonry and reinforced hollow unit masonry, they shall be based on prism test results in accordance with TMS 602, Article 1.4 B.3 submitted by the architect or engineer to the enforcement agency which demonstrate the ability of the proposed construction to meet prescribed performance criteria for strength.

    The architect or structural engineer shall establish a method of quality control of the masonry construction acceptable to the enforcement agency which shall be described in the contract documents. Verification of compliance with the requirements for the specified strength of masonry during construction shall be provided using prism test method in accordance with TMS 602, Article 1.4 B.3. Verification of compliance with the specified compressive strength prior to the start of construction shall be obtained by using the prism test method in accordance with TMS 602, Article 1.4 B.3.

    2105A.3 Mortar and grout tests. TMS 602, Article 1.4 B Compressive Strength Determination. Modify TMS 602, Article 1.4 B as follows by adding:

    5. Additional testing requirements: a. At the beginning of all masonry work, at least one test sample of the mortar shall be taken on 3 successive working days and at least at 1-week intervals thereafter. Where mortar is based on a proportion specification, mortar shall be sampled and tested during construction in accordance with ASTM C780, including Annex 4, to verify the proportions specified in ASTM C270, Table 2. Where mortar is based on a property specification, mortar shall be laboratory prepared and tested prior to construction in accordance with ASTM C780 to verify the properties specified in ASTM C270, Table 1 and field sampled and tested during construction in accordance with ASTM C780 to verify the proportions with the laboratory tests. [DSA-SS] Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 and must be accompanied by corresponding certificates of compliance with current test reports, material certificates and delivery ticket. Documents shall be provided to the project inspector, DSA certified masonry inspector and laboratory of record. [OSHPD 1 & 4] Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 with a material certificate.

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  • CBC § 2.2 Medium relevance — show source text

    Documents shall be provided to the project inspector, DSA certified masonry inspector and laboratory of record._ b. Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet of masonry wall area. The grout shall meet the minimum strength requirement given in ASTM C476/TMS 602 Section 2.2, or greater as specified. c. Additional samples shall be taken whenever any change in materials or job conditions occur, as determined by the build- ing official.

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    d. Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. When the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in this section are not required. Exception: For nonbearing nonshear masonry walls not exceeding total wall height of 12 feet above the top of the foun- dation, mortar test shall be permitted to be limited to those at the beginning of masonry work for each mix design. 2115.4.2 Masonry core testing. Two cores shall be taken from each building for each 5,000 square feet (465 m [2] ) of the masonry wall area or fraction thereof. The approved agency shall perform or observe the coring of the masonry walls and sample locations shall be subject to approval of the registered design professional.

    Core samples shall comply with the following: 1. Cored no sooner than 7 days after grouting of the selected area; 2. Be a minimum of 3 [ 3] / 4 inches (96 mm) in nominal diameter; and 3. Sampled in such a manner as to exclude any masonry unit webs, mortar joint, or reinforcing steel. If all cells contain rein- forcement, alternate core locations or means to detect void or delamination shall be selected by the registered design professional and approved by the building official.

    Visual examination of all cores shall be made by an approved agency and the condition of the cores reported as required by the California Administrative Code. Shear test shall test both joints between the grout core and the outside wythes or face shell of the masonry 28 days after grouting of the sample area using a shear test apparatus acceptable to the enforcement agency. Core samples shall not be soaked before testing. Core samples to be tested shall be stored in sealed plastic bags or non-absorbent containers immediately after coring and for at least 5 days prior to testing. The average unit shear value for each pair of cores (4 shear tests) from each 5,000 square feet of wall area (or less) on the cross section of the cores shall not be less than 2.5 √ f ′ m psi.

  • CBC § 12.7 Medium relevance — show source text

    Bolts shall be solidly embedded in grout._ 5. Bent bar anchor bolts shall not be allowed. The maximum size anchor shall be [1] / 2 -inch (12.7 mm) diameter for 6-inch (152 mm) nominal masonry, [3] / 4 -inch (19.1 mm) diameter for 8-inch (203 mm) nominal masonry, [7] / 8 -inch (22.2 mm) diameter for 10-inch (254 mm) nominal masonry, and 1-inch (25.4 mm) diameter for 12-inch (305 mm) nominal masonry. 6. Bolts shall be accurately set with templates or by approved equivalent means and held in place to prevent dislocation during grouting.

    2104.2.4 TMS 602, Article 3.5 F.1 Grout key. Replace TMS 602, Article 3.5 F.1 as follows: 1. Between grout pours or where grouting has been stopped more than an hour, a horizontal construction joint shall be formed by terminating grout a minimum of 1 [1] / 2 inches (38.1 mm) and a maximum of one-half the masonry unit height below a mortar joint, except at the top of the wall. Where bond beams occur, the grout pour shall be terminated a minimum of [1] / 2

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    inch (12.7 mm) below the mortar joint. Horizontal reinforcement shall be placed in bond beam units with a minimum grout cover of 1 inch (25.4 mm) above reinforcing steel for each grout pour.

    2104.3 Aluminum equipment. [OSHPD 1R, 2 & 5] Grout shall not be handled nor pumped utilizing aluminum equipment unless it can be demonstrated with the materials and equipment to be used that there will be no deleterious effect on the strength of the grout.

    SECTION 2105—QUALITY ASSURANCE

    2105.1 General. A quality assurance program shall be used to ensure that the constructed masonry is in compliance with the approved construction documents.

    The quality assurance program shall comply with the inspection and testing requirements of Chapter 17 and TMS 602. 2105.2 Compressive strength , f ′ m . [OSHPD 1R, 2 & 5] Testing of masonry shall be provided in accordance with TMS 602, Article 1.4 B.

    Exception: Where values of f ′ m greater than 2,000 psi (13.79 MPa) are used in the design of reinforced grouted multi-wythe masonry and reinforced hollow unit masonry, they shall be based on prism test results in accordance with TMS 602, Article 1.4 B.3 submitted by the architect or engineer to the enforcement agency which demonstrate the ability of the proposed construction to meet prescribed performance criteria for strength exceed 3,000 psi (20.7 MPa).

  • CBC § 464.5 Medium relevance — show source text

    Mortar sampling and testing is not required for_ preblended mortars in conformance with ASTM C1714 with a material certificate. b. Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet (464.5 m [2] ) of masonry wall area. They shall meet the minimum strength requirement given in ASTM C476/TMS 602 Section 2.2 or greater as specified. c. Additional samples shall be taken whenever any change in materials or job conditions occur, as determined by the building official.

    d. Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. When the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in this section are not required.

    Exception: For nonbearing nonshear masonry walls not exceeding total wall height of 12 feet (3658 mm) above top of foundation, mortar test shall be permitted to be limited to those at the beginning of masonry work for each mix design. 2105.4 Masonry core testing . [OSHPD 1R, 2 & 5] Two cores shall be taken from each building for each 5,000 square feet (465 m [2] ) of the masonry wall area or fraction thereof. The approved agency shall perform or observe the coring of the masonry walls and sample loca- tions shall be subject to approval of the registered design professional.

    Core samples shall comply with the following: 1. Cored no sooner than 7 days after grouting of the selected area; 2. Be a minimum of 3 [3] / 4 inch (95.25 mm) nominal diameter; and 3. Sampled in such a manner as to exclude any masonry unit webs, mortar joint or reinforcing steel. If all cells contain reinforce- ment, alternate core locations or means to detect voids or delamination shall be selected by the registered design professional and approved by the building official.

    Visual examination of all cores shall be made by an approved agency and the condition of the cores reported as required by the Cali- fornia Administrative Code. Shear tests of both joints between the grout core and the outside wythes or face shell of the masonry shall be made 28 days after grouting of the sample area using a shear test apparatus acceptable to the enforcement agency. Core samples shall not be soaked before testing. Core samples to be tested shall be stored in sealed plastic bags or nonabsorbent containers immediately after coring and for at least 5 days prior to testing. The average unit shear value for each pair of cores (4 shear tests) from each 5,000 square feet of wall area (or less) on the cross section of core shall not be less than 2.5 √ f ′ m psi.

    All cores shall be submitted to an approved agency for examination, including core specimens where a face shell separates from the grout core during the coring operation. The approved agency shall report the location where each core was taken, report the find- ings of their visual examination of each core, identify which cores were selected for shear testing, and report the results of the shear

    21-6 2025 CALIFORNIA BUILDING CODE

  • CBC § 2115.1 Medium relevance — show source text

    SECTION 2115-ADDITIONAL REQUIREMENTS FOR COMMUNITY COLLEGES [DSA-SS/CC]

    2115.1 General. In addition to the provisions of this chapter, the following requirements shall apply to community college buildings regulated by the Division of the State Architect-Structural Safety/Community Colleges (DSA-SS/CC).

    2115.1.1 Prohibitions. The following design, systems and materials in TMS 402/602 are not permitted by DSA: 1. Unreinforced masonry. 2. Autoclaved aerated concrete (AAC) masonry. 3. Empirical design of masonry.

    4. Adobe construction.

    5. Ordinary reinforced masonry shear walls. 6. Intermediate reinforced masonry shear walls. 7. Prestressed masonry shear walls. 8. Direct design of masonry. 9. Design of masonry infill. 10. Prescriptive design of masonry partition walls. 11. Limit design method. 12. Glass fiber reinforced polymer (GFRP) reinforced masonry.

    2115.2 Masonry construction materials.

    2115.2.1 Metal reinforcement and accessories. The frequency of sampling for unidentifiable reinforcing bars may alternatively be in accordance with Section 1909.2.3.

    2115.2.2 Air entrainment. Air-entraining substances shall not be used in grout.

    2115.2.3 Specified compressive strength of masonry and grout. Replace TMS 402 Table 4.3.1 with the following.

    TABLE 4.3.1—SPECIFIED COMPRESSIVE STRENGTH REQUIREMENTS Col2 Col3
    TYPE OF MASONRY SPECIFIED COMPRESSIVE STRENGTH OF MASONRY SPECIFIED COMPRESSIVE STRENGTH OF GROUT
    Concrete masonry 2,000 psi (13.79 MPa) ≤ f'm ≤ 3,000 psi (20.68 MPa) f'g ≥ f'm ≤ 5,000 psi (34.47 MPa)
    Clay masonry 1,500 psi (10.34 MPa) ≤ f'm ≤ 4,500 psi (31.02 MPa) f'g≤ 6,000 (41.37 MPa)

    2115.3 Construction.

    2115.3.1 Masonry construction. Architectural cast stone construction shall be considered as an alternative system.

    2115.3.2 Reinforced grouted masonry.

    2115.3.2.1 TMS 602, Article 3.3 B Placing mortar and units. Modify TMS 602, Article 3.3 B.2.c as follows: c. Remove masonry protrusions extending greater than [1] / 4 inch ( 6.4 mm) into cells or cavities to be grouted.

    2025 CALIFORNIA BUILDING CODE 21-19

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

    >

    MASONRY

  • CBC § 2104A.1.3.10.5 Medium relevance — show source text

    2104A.1.3.10.5 TMS 602, Article 3.5 B Confinement. Add the following to TMS 602, Article 3.5 B: 1. Construct vertical grout barriers or dams of solid masonry across the grout space the entire height of the wall to control horizontal grout flow. Space grout barriers not more than 30 feet (9.14 m) apart.

    2104A.1.3.11 Reinforced hollow unit masonry.

    2104A.1.3.11.1 TMS 602, Article 2.3 A & 2.3 B Masonry unit materials. Add the following to TMS 602, Articles 2.3 A and 2.3 B: 1. In reinforced hollow unit masonry, place horizontal reinforcement in bond beam units. The depth of the bond beam channel below the top of the unit shall be 1 [1] / 2 inches (38.1 mm) minimum and the width shall be 3 inches (76.2 mm) minimum.

    2104A.1.3.11.2 TMS 602, Article 3.5 B Confinement. Add the following to TMS 602, Article 3.5 B: 2. All cells shall be solidly filled with grout in reinforced hollow unit masonry. Exception: Reinforced hollow unit masonry laid in running bond used for freestanding site walls or interior nonbear- ing non-shear wall partitions may be grouted only in cells containing vertical and horizontal reinforcement. 3. [DSA-SS] Vertical cells to be filled shall have vertical alignment sufficient to maintain a clear grout space dimension of not less than that given in Section 2104A.1.3.5, Table 7.

    SECTION 2105 A —QUALITY ASSURANCE

    2105 A .1 General. A quality assurance program shall be used to ensure that the constructed masonry is in compliance with the approved construction documents.

    The quality assurance program shall comply with the inspection and testing requirements of Chapter 17 A and TMS 602 and Sections 2105A.2 through 2105A.4.

    2105A.2 Compressive strength, f ′ m . Testing of masonry shall be provided in accordance with TMS 602, Article 1.4 B.

    Exception: Where values of f ′ m greater than 2000 psi (13.79 MPa) are used in the design of reinforced grouted multi-wythe masonry and reinforced hollow unit masonry, they shall be based on prism test results in accordance with TMS 602, Article 1.4 B.3 submitted by the architect or engineer to the enforcement agency which demonstrate the ability of the proposed construction to meet prescribed performance criteria for strength.

  • CBC § 21A-7 Medium relevance — show source text

    _ [OSHPD 1 & 4] Mortar sampling and testing is not required for preblended mortars in conformance with ASTM C1714 with a material certificate.

    2025 CALIFORNIA BUILDING CODE 21A-7

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

    MASONRY

    b. Samples of grout shall be taken for each mix design, each day grout is placed, and not less than every 5,000 square feet of masonry wall area. They shall meet the minimum strength requirement given in ASTM C476/TMS 602, Section 2.2, or greater as specified. c. Additional samples shall be taken whenever any change in materials or job conditions occur, as determined by the building official.

    d. Test specimens for mortar and grout shall be made as set forth in ASTM C780/C1586 and ASTM C1019. When the prism test method is used in accordance with TMS 602, Article 1.4 B.3 during construction, the tests in this section are not required.

    Exception: For nonbearing non-shear masonry walls not exceeding total wall height of 12 feet above top of foundation, mortar tests shall be permitted to be limited to those at the beginning of masonry work for each mix design. 2105A.4 Masonry core testing. Two cores shall be taken from each building for each 5,000 square feet (465 m [2] ) of the masonry wall area or fraction thereof. The approved agency shall perform or observe the coring of the masonry walls and sample locations shall be subject to approval of the registered design professional.

    Core samples shall comply with the following: 1. Cored no sooner than 7 days after grouting of the selected area; 2. Be a minimum of 3 [3] / 4 inches in nominal diameter; and 3. Sampled in such a manner as to exclude any masonry unit webs, mortar joint, or reinforcing steel. If all cells contain rein- forcement, alternate core locations or means to detect void or delamination shall be selected by the registered design professional and approved by the building official.

    Visual examination of all cores shall be made by an approved agency and the condition of the cores reported as required by the Cali- fornia Administrative Code. Shear test both joints between the grout core and the outside wythes or face shell of the masonry 28 days after grouting of the sample area using a shear test apparatus acceptable to the enforcement agency. Core samples shall not be soaked before testing. Core samples to be tested shall be stored in sealed plastic bags or non-absorbent containers immediately after coring and for at least 5 days prior to testing. The average unit shear value for each pair of cores (4 shear tests) from each 5,000 square feet of wall area (or less) on the cross section of core shall not be less than 2.5 √ f ′ m psi.

    All cores shall be submitted to an approved agency for examination, including core specimens where an outside wythe or face shell separates from the grout core prior to shear testing, including during the coring operation. [DSA-SS] At this condition, a shear value of zero shall be assigned to the separated joint interface and the average unit shear value shall include this result.

  • CBC § 73.4 Medium relevance — show source text

    1.2. When tests are required by the enforcing agency, they shall be performed in the following manner: Two test cylinders, for compressive strength tests, shall be made for each 8,000 square feet (743 m [2] ) of surface area placed. A minimum of two test cylinders shall be made each day. Each strength test result shall be the average of two cylinders from the same sample tested at 28 days or at a specified earlier date. 1.3. The minimum air-dry density shall be 90 pounds per cubic foot (1,440 kg/m3). The minimum design compressive strength shall be 1,000 psi (6,890 kPa) when the curing procedure specified herein is applied. The minimum design compressive strength shall be 1,250 psi (8,619 kPa) if the slab is placed in a covered area of a building and a specified curing medium is not applied. The specified design compressive strength shall be increased 20 percent when the specified strength is greater than 1,000 psi (6,890 kPa) and the slab is placed in a covered area of a building and a specified curing medium is not applied. 1.4. The cellular concrete shall be sampled at the point of deposit in accordance with the applicable procedures of ASTM C172, Sampling Fresh Concrete. Cylinder molds shall be either 3 inches by 6 inches (76 mm by 152 mm) or 6 inches by 12 inches (152 mm by 305 mm). Lightly tap the sides of the mold with a rubber hammer while filling the mold instead of rodding the mix. Moist cure the specimens for seven days at 73.4°F (40.8°C) plus or minus 3°F (1.7°C). At the age of seven days, remove the specimens from the moist condition and store in a temperature of 73.4°F (40.8°C) plus or minus 3°F (1.7°C) and a relative humidity of 50 plus or minus 10 percent for 21 days; remove and air dry until the time of test at 28 days. The compressive strength test shall be in accordance with ASTM C39, Compressive Strength of Cylindrical Concrete Specimens. Determine the air-dry-unit weight at 28 days. 2. Regardless of the provisions of Subsections 4.1 and 4.2 in Section 4 of Bulletin No. 65, relating to placing, finishing and curing, the following shall apply to these regulations. 2.1. The concrete shall be placed, finished and cured to produce a level, smooth surface. The concrete shall be placed in a single layer to a minimum thickness of 1 [1] / 2 inches (38 mm). The deviation from a plan shall not exceed [1] / 4 inch (6 mm) in any 10 feet (3048 mm). The final finish of the concrete shall be suitable for the applica- tion of the specified wear- resistant covering. Cracks wider than [1] / 8 inch (3 mm) shall be repaired. 2.2. Install a water-resistant membrane between wood or plywood subfloors and the cellular concrete to prevent _leakage of the concrete and wetting of the subfloor.

Frequently asked questions

Who decides whether to use prism tests instead of mortar/grout specimen testing?

The architect or structural engineer must establish the quality‑control method acceptable to the enforcement agency; prism tests per TMS 602 Article 1.4 B.3 are the prescribed prism‑test method and, if used, can substitute for the routine mortar/grout specimen tests (§ 2105.2 / § 2105.3).

How many grout samples do I need if I place grout one day and the wall area is only 3,000 ft2?

You must take samples for each day grout is placed (that one day = at least one sample) and the minimum every‑5,000‑ft2 rule is a floor — because 3,000 ft2 is less than 5,000 ft2 the “every 5,000 ft2” minimum would be satisfied by that daily sample (§ 2105.3).

When can cores be taken for testing?

Cores must not be taken sooner than 7 days after grouting of the selected area; shear testing of the core interfaces is performed 28 days after grouting and cores must be stored sealed for at least 5 days prior to testing (§ 2105.4 / § 2115.4.2).

Are preblended mortars always exempt from field sampling?

Preblended mortars in conformance with ASTM C1714 may be exempt from mortar sampling/testing, but DSA/DSA‑SS/CC projects require material certificates and supporting documentation to be provided to the project inspector, DSA certified masonry inspector and laboratory of record (§ 2105.3; § 2115.4.1).

What acceptance criterion applies to core shear tests?

The average unit shear value for each pair of cores (four shear tests) from each 5,000 ft2 (or less) on the core cross section shall not be less than 2.5 × √(f′m) psi (§ 2105.4 / § 2115.4.2).

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