CBC · California Building Code
Allowed masonry design methods and DSA/OSHPD prohibitions
For DSA and OSHPD projects the CBC requires TMS‑based engineered masonry only and explicitly bans a list of outdated or higher‑risk methods (for example unreinforced masonry, empirical design, AAC, certain reinforced shear‑wall methods and GFRP masonry) — see § 2101.2, § 2101A.1.3 and § 2115.1.1; material strength and inspection rules (e.g., § 2115.2.3 and Chapter 17 ties) still apply and alternatives require formal agency approval.
Last reviewed: July 5, 2026
What the code requires — 2-4 sentences
The California Building Code requires masonry design to follow the national TMS standards referenced in Chapter 21 (TMS 402, TMS 403 or TMS 404) unless a state adopting agency limits those options; see § 2101.2. For buildings regulated by the Division of the State Architect (DSA‑SS / DSA‑SS/CC) and by OSHPD, Chapter 21A/21 includes explicit prohibitions: a list of specific masonry methods, systems and materials that those state agencies do not permit appears in § 2101A.1.3 (Chapter 21A) and § 2115.1.1 (additional requirements for community colleges / DSA).
Requirements in detail
Which design methods are permitted (baseline)
- The baseline code requires compliance with the TMS standards listed in Chapter 21: TMS 402, TMS 403 or TMS 404. This is the starting point for allowable design methods under the CBC. See § 2101.2.
- Note: OSHPD explicitly disallows use of TMS 403 for OSHPD-regulated applications per the Chapter 21 amendments. See § 2101.2 where the OSHPD note appears.
Which methods/systems/materials are prohibited by DSA and OSHPD
Both Chapter 21A (DSA-SS / OSHPD adoption) and Section 2115 (DSA‑SS/CC—community colleges) enumerate prohibited methods. The lists overlap; the important prohibitions designers must know are summarized below and are stated explicitly in the code.
| Decision item | Allowed / prohibited | Code Reference |
|---|---|---|
| Unreinforced masonry | Prohibited for DSA / OSHPD applications | § 2101A.1.3; § 2115.1.1. |
| Autoclaved aerated concrete (AAC) masonry | Prohibited for DSA / OSHPD applications | § 2101A.1.3; § 2115.1.1. |
| Empirical design of masonry | Prohibited for DSA / OSHPD applications | § 2101A.1.3; § 2115.1.1. |
| Adobe construction | Prohibited for DSA / OSHPD applications | § 2101A.1.3; § 2115.1.1. |
| Ordinary / Intermediate / Prestressed reinforced masonry shear walls | Prohibited for DSA (community colleges) and listed in Chapter 21 variants | § 2101A.1.3; § 2115.1.1. |
| Direct design, infill design, prescriptive partition design, limit design method | Prohibited for DSA / OSHPD applications | § 2101A.1.3; § 2115.1.1. |
| GFRP (glass fiber reinforced polymer) reinforced masonry | Prohibited for DSA / OSHPD applications | § 2101A.1.3; § 2115.1.1. |
| TMS 403 (direct design handbook) | Not permitted by OSHPD (see agency note) | § 2101.2 (OSHPD note). |
(Each of the prohibition items above is taken from the code lists in § 2101A.1.3 (Chapter 21A) and § 2115.1.1 (Chapter 21, additional DSA requirements).)
Special inspection and testing expectations
- Chapter 21(A) requires the special inspection of masonry as defined in Chapter 17(A) or by an itemized program that meets or exceeds Chapter 17(A) requirements; see § 2101A.3 / § 2101.3. Designers must plan special inspections consistent with those provisions when masonry is used in regulated projects.
Agency adoption and scope notes
- Chapter 21A states which state agencies adopt the chapter (DSA‑SS and OSHPD) and explains that some amendments are agency‑specific; see § 2101A.1.1 and § 2101A.1.2. This is why the prohibitions apply to DSA/OSHPD projects but may not apply to ordinary municipal projects.
Exceptions & special cases
- The CBC provides a process for alternative materials, designs and methods (performance-based alternatives) under § 104.2.3; however, DSA does not permit the ICC Performance Code for alternative structural designs, and state agencies may impose their own restrictions on alternatives. For regulated DSA/OSHPD work, expect stricter review and limited acceptance of alternate masonry systems. The alternative system rules are in § 104.2.3 (see agency notes) — consult the enforcement agency and the relevant state adopting agency early.
- The OSHPD amendment language in Chapter 21 (and the Chapter 21A agency notes) means a method that is allowed by the model TMS standards may still be disallowed for DSA/OSHPD projects; always check the agency‑specific prohibitions in § 2101A.1.3 and § 2115.1.1.
- If an item is not explicitly listed in the prohibition sections, do not assume permissibility — some methods are governed by other sections (e.g., special inspection rules, material strength requirements). When in doubt, obtain a written determination from the enforcement agency as provided in § 104.2.2.
Common mistakes
- Assuming the TMS standard used at the national level automatically applies for DSA/OSHPD projects — Chapter 21A/2115 contain agency‑level prohibitions that override permissibility for those projects (see § 2101A.1.3 and § 2115.1.1).
- Designing by empirical methods (or proposing unreinforced masonry) for a DSA or OSHPD project — empirical design and unreinforced masonry are explicitly prohibited.
- Forgetting OSHPD’s specific ban on TMS 403 for OSHPD work: a designer who uses TMS 403 for an OSHPD project will face rejection unless an approved alternative is established. See § 2101.2.
- Omitting a special inspection plan or failing to meet Chapter 17(A) testing when Chapter 21 requires it — Chapter 21(A) ties into Chapter 17(A) special inspection rules.
Worked example — concrete scenario
Scenario: A design firm is preparing structural masonry design for a new community college classroom building (DSA‑SS/CC jurisdiction). They propose grouted concrete masonry with specified masonry compressive strength f′m = 2,500 psi and grout f′g = 3,000 psi, and intend to use reinforced masonry shear walls.
Application of the code:
- Because the project is a community college building under DSA‑SS/CC, the DSA prohibitions in § 2115.1.1 apply. § 2115.1.1 explicitly prohibits ordinary, intermediate and prestressed reinforced masonry shear walls and several other methods for DSA‑regulated community college work. Therefore the proposed use of reinforced masonry shear walls of the prohibited types is not permitted by the DSA amendment and must be changed to an acceptable seismic force‑resisting system or handled via an approved alternative.
- On material strength: § 2115.2.3 replaces the TMS table for specified compressive strength and lists allowable ranges. For concrete masonry, the code states 2,000 psi ≤ f′m ≤ 3,000 psi and grout strength f′g ≥ f′m and ≤ 5,000 psi; the proposed f′m = 2,500 psi and f′g = 3,000 psi fall inside the numeric ranges required by § 2115.2.3 — but material strength compliance alone does not permit the prohibited shear wall system.
- Result: The firm must either (a) change the lateral system to one not prohibited by § 2115.1.1, (b) develop an approved alternative (subject to DSA review and limitations on alternative structural systems), or (c) seek a written acceptance from DSA under the alternative procedures — recognizing DSA’s noted restrictions on alternatives. See § 2101.2 and § 104.2.3 for the alternative pathway and agency notes.
Related provisions
- § 2101.2 — Design methods: TMS 402, 403 or 404 are baseline standards; OSHPD notes regarding TMS 403 appear here.
- § 2101A.1.3 — Chapter 21A prohibitions (agency list of prohibited masonry methods).
- § 2115.1.1 — Additional DSA (community college) prohibitions (the § 2115 DSA list).
- § 2101.3 / § 2101A.3 — Special inspection requirements for masonry (ties to Chapter 17/17A).
- § 2115.2.3 — Specified compressive strength requirements for masonry and grout (DSA‑specific replacement of TMS table).
- § 104.2.3 — Alternative materials / design / methods (process for alternatives; agency limitations discussed).
Code references
Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:
CBC § 2101A.1.2 High relevance — show source text
centers.
2101A.1.2 Amendments in this chapter. DSA-SS and OSHPD 1 & 4 adopt this chapter and all amendments.
Exception: Amendments adopted by only one agency appear in this chapter preceded with the appropriate acronym of the adopt- ing agency, as follows: 1. Division of the State Architect-Structural Safety:
[DSA-SS] For applications listed in Section 1.9.2.1. 2. Office of Statewide Hospital Planning and Development:
[OSHPD 1] - For applications listed in Section 1.10.1.
[OSHPD 4] - For applications listed in Section 1.10.4.
2101A.1.3 Prohibition. The following design methods, systems and materials in TMS 402/602 are not permitted by DSA-SS and OSHPD:
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.
2101 A .2 Design methods. Masonry shall comply with the provisions of TMS 402 or TMS 404 as well as applicable requirements of this chapter.
2101 A .2.1 Masonry veneer. Masonry veneer shall comply with the provisions of Chapter 14.
2101 A .3 Special inspection. The special inspection of masonry shall be as defined in Chapter 17 A, or an itemized testing and inspection program shall be provided that meets or exceeds the requirements of Chapter 17 A .
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SECTION 2102 A —NOTATIONS
2102 A .1 General. The following notations are used in the chapter:
NOTATIONS .
d b = Diameter of reinforcement, inches (mm).
F s = Allowable tensile or compressive stress in reinforcement, psi (MPa).
f r = Modulus of rupture, psi (MPa).
f s = Computed stress in reinforcement due to design loads, psi (MPa).
L s = Distance between supports, inches (mm).
l d = Required development length or lap length of reinforcement, inches (mm).
P = The applied load at failure, pounds (N).
S t = Thickness of the test specimen measured parallel to the direction of load, inches (mm).
S w = Width of the test specimen measured parallel to the loading cylinder, inches (mm).
SECTION 2103 A —MASONRY CONSTRUCTION MATERIALS
CBC § 1.11. High relevance — show source text
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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21 A MASONRY
User notes:
About this chapter: Chapter 21A provides comprehensive and practical requirements for masonry construction. Chapter 21A is applicable to structures regulated by the Division of the State Architect-Structural Safety—including public elementary and secondary schools, community colleges, and state-owned or state-leased essential services buildings (applications listed in Sections 1.9.2.1
[DSA-SS] and 1.9.2.2 [DSA-SS/CC])—and by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development—including hospitals and correctional treatment centers (applications listed in Sections 1.10.1
[OSHPD 1] and 1.10.4 [OSHPD 4]).
SECTION 2101 A —GENERAL
2101 A .1 Scope. This chapter shall govern the materials, design, construction and quality of masonry.
2101A.1.1 Application. The scope of application of Chapter 21A is as follows: 1. Structures regulated by the Division of the State Architect-Structural Safety (DSA-SS), which include those applications listed in Section 1.9.2.1. These applications include public elementary and secondary schools, community colleges and state- owned or state-leased essential services buildings. 2. Applications listed in Sections 1.10.1 and 1.10.4 regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD). These applications include hospitals and correctional treatment
centers.
2101A.1.2 Amendments in this chapter. DSA-SS and OSHPD 1 & 4 adopt this chapter and all amendments.
Exception: Amendments adopted by only one agency appear in this chapter preceded with the appropriate acronym of the adopt- ing agency, as follows: 1. Division of the State Architect-Structural Safety:
[DSA-SS] For applications listed in Section 1.9.2.1. 2. Office of Statewide Hospital Planning and Development:
[OSHPD 1] - For applications listed in Section 1.10.1.
[OSHPD 4] - For applications listed in Section 1.10.4.
2101A.1.3 Prohibition. The following design methods, systems and materials in TMS 402/602 are not permitted by DSA-SS and OSHPD:
1. Unreinforced masonry. 2. Autoclaved aerated concrete (AAC) masonry. 3. Empirical design of masonry.
4. Adobe construction.
CBC § 2101.1 High relevance — show source text
2025 (Group B) Code Development Cycle.
SECTION 2101—GENERAL
2101.1 Scope. This chapter shall govern the materials, design, construction and quality of masonry.
2101.1.1 Application. [DSA-SS/CC, OSHPD] The scope of application of Chapter 21 is as follows: 1. Structures regulated by the Division of the State Architect—Structural Safety/Community Colleges (DSA-SS/CC) which include those applications listed in Section 1.9.2.2. 2. Structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital planning and development (OSHPD), which include hospital buildings removed from general acute care service, skilled nursing facility buildings, intermediate care facility buildings and acute psychiatric hospital buildings listed in Sections 1.10.1, 1.10.2 and 1.10.5.
2101.1.2 Amendments in this chapter. [DSA-SS/CC, OSHPD] DSA-SS/CC, OSHPD adopt this chapter as amended.
2101.1.3 Identification of amendments. [DSA-SS/CC, OSHPD] 1. [DSA-SS/CC] Division of the State Architect - Structural Safety/Community Colleges amendments appear in this chapter preceded by the appropriate acronym, as follows:
[DSA-SS/CC] – For applications listed in Section 1.9.2.2. 2. [OSHPD 1R, 2 & 5] Office of Statewide Hospital Planning and Development (OSHPD) amendments appear in this chapter preceded by the appropriate acronym, as follows:
[OSHPD 1R ] - For applications listed in Section 1.10.1.
[OSHPD 2] - For applications listed in Section 1.10.2.
[OSHPD 5] - For applications listed in Section 1.10.5.
2101.1.4 Reference to other chapters. [DSA-SS/CC] Where reference within this chapter is made to sections in Chapters 17 and 18, the provisions in Chapters 17A and 18A respectively shall apply instead.
2101.1.5 Additional amendments. [DSA-SS/CC] See Section 2115 for additional requirements.
2101.2 Design methods. Masonry shall comply with the provisions of TMS 402, TMS 403 or TMS 404 as well as applicable requirements of this chapter. [OSHPD 1R, 2 & 5] TMS 403 Not permitted by OSHPD.
2101.2.1 Masonry veneer. Masonry veneer shall comply with the provisions of Chapter 14.
2101.2.2 Prohibition. [OSHPD 1R, 2 & 5] The following design methods, systems and materials in TMS402/602 are not permitted by OSHPD:
1. Unreinforced masonry. 2. Autoclaved Aerated Concrete (AAC) Masonry. 3. Empirical design of masonry.
4. Adobe construction.
CBC § 1.10.1. High relevance — show source text
[OSHPD 1R ] - For applications listed in Section 1.10.1.
[OSHPD 2] - For applications listed in Section 1.10.2.
[OSHPD 5] - For applications listed in Section 1.10.5.
2101.1.4 Reference to other chapters. [DSA-SS/CC] Where reference within this chapter is made to sections in Chapters 17 and 18, the provisions in Chapters 17A and 18A respectively shall apply instead.
2101.1.5 Additional amendments. [DSA-SS/CC] See Section 2115 for additional requirements.
2101.2 Design methods. Masonry shall comply with the provisions of TMS 402, TMS 403 or TMS 404 as well as applicable requirements of this chapter. [OSHPD 1R, 2 & 5] TMS 403 Not permitted by OSHPD.
2101.2.1 Masonry veneer. Masonry veneer shall comply with the provisions of Chapter 14.
2101.2.2 Prohibition. [OSHPD 1R, 2 & 5] The following design methods, systems and materials in TMS402/602 are not permitted by OSHPD:
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.
2101.3 Special inspection. The special inspection of masonry shall be as defined in Chapter 17, or an itemized testing and inspection program shall be provided that meets or exceeds the requirements of Chapter 17.
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MASONRY
SECTION 2102—NOTATIONS
2102.1 General. The following notations are used in the chapter:
NOTATIONS .
d b = Diameter of reinforcement, inches (mm).
F s = Allowable tensile or compressive stress in reinforcement, psi (MPa).
f r = Modulus of rupture, psi (MPa).
f s = Computed stress in reinforcement due to design loads, psi (MPa).
L s = Distance between supports, inches (mm).
l d = Required development length or lap length of reinforcement, inches (mm).
P = The applied load at failure, pounds (N).
S t = Thickness of the test specimen measured parallel to the direction of load, inches (mm).
S w = Width of the test specimen measured parallel to the loading cylinder, inches (mm).
SECTION 2103—MASONRY CONSTRUCTION MATERIALS
CBC § 1.9.2.1. High relevance — show source text
[DSA-SS] - For applications listed in Section 1.9.2.1.
[DSA-SS/CC] - For applications listed in Section 1.9.2.2. 2. Office of Statewide Hospital Planning and Development (OSHPD) amendments appear in this chapter preceded by the appropriate acronym, as follows:
[OSHPD 1] - For applications listed in Section 1.10.1.
[OSHPD 1R] - For applications listed in Section 1.10.1.
[OSHPD 2] - For applications listed in Section 1.10.2.
[OSHPD 4] - For applications listed in Section 1.10.4.
[OSHPD 5] - For applications listed in Section 1.10.5.
2301.1.4 Reference to other chapters. [DSA-SS, DSA-SS/CC, OSHPD]
2301.1.4.1 [DSA-SS and OSHPD 1 & 4] Where reference within this chapter is made to sections in Chapters 16, 17, 18, 19, 21 and 22, the provisions in Chapters 16A, 17A, 18A, 19A, 21A and 22A, respectively shall apply instead.
2301.1.4.2 [DSA-SS/CC] Where reference within this chapter is made to sections in Chapters 17 and 18, the provisions in Chapters 17A and 18A respectively shall apply instead.
2301.1.5 Prohibition. [DSA-SS & DSA-SS/CC & OSHPD 1, 1R, 2, 4 & 5] The following design methods, systems and materials are not permitted by DSA and OSHPD: 1. Straight-sheathed horizontal lumber diaphragms. 2. Gypsum-based sheathing shear walls and portland cement plaster shear walls. 3. Shear wall foundation anchor bolt washers in accordance with exception to AWC SDPWS Section 4.3.6.4.3.
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WOOD
4. Wood structural panel shear walls and diaphragms using staples as fasteners.
5. Unblocked shear walls.
6. Any wood structural panel sheathing used for diaphragms and shear walls that are part of the seismic force-resisting system, not applied directly to framing members. 7. Single and double diagonally sheathed lumber walls used to resist seismic forces. 8. Log structures in accordance with ICC 400. 9. [OSHPD 1, 1R, 2, 4 & 5] Cross-laminated timber used as part of the seismic force-resisting system, unless approved as an alternative system in accordance with Section 104.2.3. [DSA-SS, DSA-SS/CC] Not adopted by DSA.
CBC § 2.3. High relevance — show source text
1 to 2.3._ Exception: The gap-to-side plate thickness ratio shall be permitted to be modified for moment connections with unequal beam sizes on opposite sides of the column or when orthogonal beams acting as drag connections frame into the side plate. 8. Demand critical fillet welds {2}, {5}, {5a} and {7} shall have Magnetic Particle Testing (MT) in accordance with AWS D1.1 for procedure, technique and acceptance. Inspect the beginning and end of these welds for a 6-inch length, plus any location along the length of the weld where a start and restart is visually noted for a distance of 6 inches on either side of the start/stop location.
2202.4.3 Modifications to AISC 358 Chapter 11 Bolted Moment Connection The bolted sideplate steel moment connection shall be permitted, provided: 1. The beams shall consist of either rolled or built-up wide flange sections. Columns shall consist of rolled or built-up wide flange sections or noncomposite built-up box or HSS with a minimum wall thickness of [3] / 4 inch (19 mm), or satisfy the requirements of width-to-thickness ratios of highly ductile members in AISC 341-16. 2. The biaxial dual-strong axis and column minor axis configurations of the moment connection shall be considered as an alternative system. 3. For SMF and IMF systems, on the sideplate standard or configuration A the U-shaped cover plates shall be used with the k dimension extension. The k dimension extension length is defined as beam depth d b /6, rounded to the nearest [1] / 2 inch (12.7 mm).
4. The hinge-to-hinge span to beam depth, L h /d, shall be greater than or equal to 4.5. 5. The width-to-thickness ratios for beam flanges shall not be less than 3.5. Exception: For width-to-thickness ratios less than 3.5 the C pr shall be calculated in accordance with that for welded side- plate connections but in no case shall the width-to-thickness ratio be less than 3.0. 6. The minimum bolt-to-bolt spacing shall not be less than 3 bolt diameters. 7. The extension of the side plates beyond the face of the column shall be within the range of 0.65d to 1.5d. 8. The gap-to-side plate thickness ratio shall range from 2.1 to 2.3.
Exception: The gap-to-side plate thickness ratio shall be permitted to be modified for moment connections with unequal beam sizes on opposite sides of the column or when orthogonal beams acting as drag connections frame into the side plate. 9. Demand Critical fillet welds {2}, {5}, {5a} and {8} shall have Magnetic Particle Testing (MT) in accordance with AWS D1.1 for procedure, technique and acceptance. Inspect the beginning and end of these welds for a 6-inch (152 mm) length, plus any location along the length of the weld where a start and restart is visually noted for a distance of 6 inches (152 mm) on either side of the start/stop location. 10. The connection specific factor to account for peak connection strength, C pr _, shall be between 1.15 and 1.35.
CBC § 104.2.2.3 Medium relevance — show source text
[A] 104.2.2.3 Content. The technical opinion and report shall analyze the properties of the design, operation or use of the building or premises and the facilities and appurtenances situated thereon to identify and propose necessary recommendations.
[A] 104.2.2.4 Tests. Where there is insufficient evidence of compliance with the provisions of this code, the building official shall have the authority to require tests as evidence of compliance. Test methods shall be as specified in this code or by other recognized test standards. In the absence of recognized test standards, the building official shall approve the testing procedures. Such tests shall be performed by a party acceptable to the building official.
[A] 104.2.3 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, provided that any such alternative has been approved.
Exception: Performance-based alternative materials, designs or methods of construction and equipment complying with the International Code Council Performance Code . This exception shall not apply to alternative structural materials or to alternative structural designs. [DSA-SS, DSA-SS/CC] The International Code Council Performance Code is not permitted by DSA.
[DSA-SS, DSA-SS/CC & OSHPD 1, 1R, 2, 4 & 5] Alternative system shall satisfy ASCE 7 Section 1.3, unless more restrictive require- ments are established by this code for an equivalent system.
[DSA-SS, DSA-SS/CC] Alternative systems shall also satisfy the California Administrative Code, Section 4-304.
[OSHPD 1, 1R, 2, 4 & 5] Alternative systems shall also satisfy the California Administrative Code, Section 7-104.
[A] 104.2.3.1 Approval authority. An alternative material, design or method of construction shall be approved where the building official finds that the proposed alternative is satisfactory and complies with Sections 104.2.3 through 104.2.3.7, as applicable.
[A] 104.2.3.2 Application and disposition. Where required, a request to use an alternative material, design or method of construction shall be submitted in writing to the building official for approval. Where the alternative material, design or method of construction is not approved, the building official shall respond in writing, stating the reasons the alternative was not approved.
[A] 104.2.3.3 Compliance with code intent. An alternative material, design or method of construction shall comply with the intent of the provisions of this code.
[A] 104.2.3.4 Equivalency criteria. An alternative material, design or method of construction shall, for the purpose intended, be not less than the equivalent of that prescribed in this code with respect to all of the following, as applicable:
Quality.
Strength.
Effectiveness.
Durability.
Safety, other than fire safety.
Fire safety.
[A] 104.2.3.5 Tests. Tests conducted to demonstrate equivalency in support of an alternative material, design or method of construction application shall be of a scale that is sufficient to predict performance of the end use configuration. Tests shall be performed by a party acceptable to the building official.
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CBC § 1.3.8 Medium relevance — show source text
1.3.8 Structural design criteria. Where design is based on ASCE 7, Chapters 16, 17, 18 or 31, the seismic ground motion, wind tunnel test-based design recommendations, analysis and design methods, material assumptions, testing requirements and acceptance criteria shall be submitted to the enforcement agency as an alternative system.
[DSA-SS] Peer review requirements in Section 322 of the California Existing Building Code shall apply to design reviews required by ASCE 7, Chapters 17, 18, 31 and ASCE 49.
[OSHPD 1 & 4] Peer review requirements in Section 1617A.1.41 of this code shall apply to design reviews required by ASCE 7, Chap- ters 17 and 18.
1617A.1.2 ASCE 7, Section 11.1.3. Replace last paragraph of ASCE 7, Section 11.1.3, by the following:
Non-building structures similar to buildings shall be designed and detailed in accordance with Chapter 12.
1617A.1.3 Reserved.
1617A.1.4 ASCE 7, Table 12.2-1. Modify ASCE 7, Table 12.2-1 as follows:
A. BEARING WALL SYSTEMS
6. Intermediate Precast Shear Walls —Not permitted by OSHPD.
18 . Light-framed walls with shear panels of all other materials —Not permitted by OSHPD and DSA-SS.
B. BUILDING FRAME SYSTEMS
- Steel ordinary concentrically braced frames— Not permitted by OSHPD.
9 . Intermediate Precast Shear Walls —Not permitted by OSHPD.
25 . Light-framed walls with shear panels of all other materials —Not permitted by OSHPD and DSA-SS.
27 . Special steel plate shear wall —Not permitted by OSHPD.
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STRUCTURAL DESIGN
C . MOMENT-RESISTING FRAME SYSTEMS
Steel special truss moment frames —Not permitted by OSHPD.
Steel intermediate moment frames —Not permitted by OSHPD except for single-story canopies and independent covered walkways where R, C d and Ω 0 = 1.5 and the roof dead load is less than 20 psf.
Steel ordinary moment frames —Not permitted by OSHPD except for single-story canopies and independent covered walk- ways where R, C d and Ω 0 = 1.5 and the roof dead load is less than 20 psf.
Cold-formed steel–special bolted moment frame —Not permitted by DSA-SS and OSHPD.
G. CANTILEVER COLUMN SYSTEMS DETAILED TO CONFORM WITH THE REQUIREMENTS FOR:
- Steel special cantilever column systems —Not permitted by OSHPD except for single-story canopies and independent covered walkways where R, C d and Ω 0 = 1.5 and roof dead load is less than 20 psf.
CBC § 2.5 Medium relevance — show source text
**_ 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.
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. 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. The approved agency shall report the location where each core was taken, the findings of their visual examination of each core, identify which cores were selected for shear testing, and the results of the shear tests. Additional cores shall be permitted to be taken at the direction of the registered design professional and with approval of the enforcement agency.
Exceptions: 1. Core sampling and testing is not required for nonbearing nonshear masonry walls, not exceeding a total wall height of 12 feet above top of foundation, built with single-wythe hollow unit concrete masonry that attaches opposite face shells using webs cast as single unit, when designed using an f ′ m not exceeding 2,000 psi (13.79 MPa). 2. An infrared thermographic survey or other nondestructive test procedures, shall be permitted to be approved as an alter- native system to detect voids or delamination in grouted masonry in lieu of core sampling and testing.
2115.5 Seismic design.
2115.5.1 TMS 402, Section 5.4.1.4. Replace TMS 402, Section 5.4.1.4 Items (a), (b), (d) & (e) by the following: (a) Vertical reinforcement shall be enclosed by lateral ties at least [3] / 8 in. (12.7 mm) in diameter.
CBC § 2109.2.4.8.2 Medium relevance — show source text
5_|||||||||||X|X|||X|||||||||| |2109|||||||||||X|X|||X|||||||||| |2109.2.4.8.2|||||||||||||||||||||X|||| |2110.1|||||||||||X|X|||X|||||||||| |2113.9.2|||X|||||||||||||||||||||| |2115|||||||||X||||||||||||||||
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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21 MASONRY
User notes:
About this chapter: Chapter 21 establishes minimum requirements for masonry construction. The provisions address: material specifications and test methods; types of wall construction; criteria for engineered and empirical designs; and required details of construction, including the execution of construction. The provisions provide a framework for applying applicable standards to the design and construction of masonry structures. Masonry design methodologies including allowable stress design, strength design and empirical design are covered by the provisions of this chapter. Also addressed are masonry fireplaces and chimneys, masonry heaters and glass unit masonry.
ICC code development note: Code change proposals to this chapter will be considered by the IBC—Structural Code Development Committee during the
2025 (Group B) Code Development Cycle.
SECTION 2101—GENERAL
2101.1 Scope. This chapter shall govern the materials, design, construction and quality of masonry.
2101.1.1 Application. [DSA-SS/CC, OSHPD] The scope of application of Chapter 21 is as follows: 1. Structures regulated by the Division of the State Architect—Structural Safety/Community Colleges (DSA-SS/CC) which include those applications listed in Section 1.9.2.2. 2. Structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital planning and development (OSHPD), which include hospital buildings removed from general acute care service, skilled nursing facility buildings, intermediate care facility buildings and acute psychiatric hospital buildings listed in Sections 1.10.1, 1.10.2 and 1.10.5.
2101.1.2 Amendments in this chapter. [DSA-SS/CC, OSHPD] DSA-SS/CC, OSHPD adopt this chapter as amended.
2101.1.3 Identification of amendments. [DSA-SS/CC, OSHPD] 1. [DSA-SS/CC] Division of the State Architect - Structural Safety/Community Colleges amendments appear in this chapter preceded by the appropriate acronym, as follows:
[DSA-SS/CC] – For applications listed in Section 1.9.2.2. 2. [OSHPD 1R, 2 & 5] Office of Statewide Hospital Planning and Development (OSHPD) amendments appear in this chapter preceded by the appropriate acronym, as follows:
CBC § 319.1.3 Medium relevance — show source text
319.1.3 For state-owned and community college buildings, where unreinforced masonry is not bearing, it may be used only to resist applied lateral loads. Where unreinforced masonry walls are part of the structure they must be assessed for stability under the applicable nonstructural evaluation procedure.
319.1.4 Public schools. [DSA-SS] For public schools, unreinforced masonry shall not be used to resist in-plane or out-of-plane seismic forces or superimposed gravity loads.
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PROVISIONS FOR ALL COMPLIANCE METHODS
319.1.5 Public schools. [DSA-SS] Wood horizontal diaphragms and wood vertical shear walls shall consist of either diagonal lumber sheathing or structural panel sheathing. Braced horizontal diaphragms may be acceptable when approved by DSA. Straight lumber sheathing may be used as diaphragms or shear walls only when overlain with structural panel sheathing. Let-in bracing, plaster (stucco), hollow clay tile, gypsum wallboard and particleboard sheathing shall not be relied upon to resist seismic forces.
319.2 Existing conditions. The existing condition and properties of the entire structure must be determined and documented by thorough inspection of the structure and site, review of all available related construction documents, review of geotechnical and engineering geologic reports, and performance of necessary testing and investigation. Where samples from the existing structure are taken or in situ tests are performed, they shall be selected and interpreted in a statistically appropriate manner to ensure that the properties determined and used in the evaluation or design are representative of the conditions and structural circumstances likely to be encountered in the structure as a whole. Adjacent structures or site features that may affect the retrofit design shall be identified.
The entire load path of the seismic-force-resisting system shall be determined, documented and evaluated. The load path includes all the horizontal and vertical elements participating in the structural response: such as diaphragms, diaphragm chords, diaphragm collectors, vertical elements such as walls frames, braces; foundations and the connections between the components and elements of the load path. Repaired or retrofitted elements and the standards under which the work was constructed shall be identified.
Data collection in accordance with ASCE 41 shall meet the following minimum levels: 1. [BSC] For state-owned buildings, the requirements shall be met following the data collection requirements of ASCE 41, Section 6.2.
2. [DSA-SS, DSA-SS/CC] For public schools and community college buildings constructed in conformance with the Field Act, visual condition assessment and usual material testing is required unless a more extensive level is required by ASCE 41, Section 6.2.
3. [DSA-SS, DSA-SS/CC] For public schools and community college buildings not constructed in conformance with the Field Act, comprehensive condition assessment and material testing is required, unless a more extensive level is required by ASCE 41, Section 6.2.
Concrete material requirements and testing for public school and community college buildings shall also comply with Sections 1911A and 1909.5 of the California Building Code, respectively.
CBC § 104.1 Medium relevance — show source text
[A] 104.1 General. The building official is hereby authorized and directed to enforce the provisions of this code.
[A] 104.2 Determination of compliance. The building official shall have the authority to determine compliance with this code, to render interpretations of this code and to adopt policies and procedures in order to clarify the application of its provisions. Such interpretations, policies and procedures:
- Shall be in compliance with the intent and purpose of this code.
- Shall not have the effect of waiving requirements specifically provided for in this code.
[A] 104.2.1 Listed compliance. Where this code or a referenced standard requires equipment, materials, products or services to be listed and a listing standard is specified, the listing shall be based on the specified standard. Where a listing standard is not specified, the listing shall be based on an approved listing criteria. Listings shall be germane to the provision requiring the listing. Installation shall be in accordance with the listing and the manufacturer’s instructions, and where required to verify compliance, the listing standard and manufacturer’s instructions shall be made available to the building official.
[A] 104.2.2 Technical assistance. To determine compliance with this code, the building official is authorized to determine compliance with this code, to require the owner or owner’s authorized agent to provide a technical opinion and report.
[A] 104.2.2.1 Cost. A technical opinion and report shall be provided without charge to the jurisdiction.
[A] 104.2.2.2 Preparer qualifications. The technical opinion and report shall be prepared by a qualified engineer, specialist, laboratory or specialty organization acceptable to the building official. The building official is authorized to require design submittals to be prepared by, and bear the stamp of, a registered design professional.
[A] 104.2.2.3 Content. The technical opinion and report shall analyze the properties of the design, operation or use of the building or premises and the facilities and appurtenances situated thereon to identify and propose necessary recommendations.
[A] 104.2.2.4 Tests. Where there is insufficient evidence of compliance with the provisions of this code, the building official shall have the authority to require tests as evidence of compliance. Test methods shall be as specified in this code or by other recognized test standards. In the absence of recognized test standards, the building official shall approve the testing procedures. Such tests shall be performed by a party acceptable to the building official.
[A] 104.2.3 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, provided that any such alternative has been approved.
Exception: Performance-based alternative materials, designs or methods of construction and equipment complying with the International Code Council Performance Code . This exception shall not apply to alternative structural materials or to alternative structural designs. [DSA-SS, DSA-SS/CC] The International Code Council Performance Code is not permitted by DSA.
[DSA-SS, DSA-SS/CC & OSHPD 1, 1R, 2, 4 & 5] Alternative system shall satisfy ASCE 7 Section 1.3, unless more restrictive require- ments are established by this code for an equivalent system.
[DSA-SS, DSA-SS/CC] Alternative systems shall also satisfy the California Administrative Code, Section 4-304.
Frequently asked questions
Can I use unreinforced masonry for a public school or community college project?
No. Unreinforced masonry is explicitly prohibited for DSA‑SS and DSA‑SS/CC regulated projects by the Chapter 21A prohibitions (§ 2101A.1.3) and by § 2115.1.1 for community colleges.
The national TMS standard allows empirical design — is that allowed in California for DSA/OSHPD projects?
No. Empirical design of masonry is listed among the methods not permitted by DSA and OSHPD in § 2101A.1.3 and § 2115.1.1. Use an allowed engineered design method or follow the agency’s alternative approval process.
I want to propose a new material or system not listed in Chapter 21 — what is the path to approval?
Submit an alternative materials/design/method application under § 104.2.3. Be aware DSA/OSHPD place limits on alternatives (for example, the ICC Performance Code is not accepted by DSA for structural alternatives), so discuss the proposal early with the enforcement agency.
Does OSHPD allow TMS 403 direct‑design methods?
OSHPD’s chapter note indicates TMS 403 is not permitted for OSHPD applications — see § 2101.2 where the OSHPD note appears. Confirm with OSHPD project reviewers.
Are the prohibitions the same for ordinary municipal projects not regulated by DSA/OSHPD?
No — the prohibitions in § 2101A.1.3 and § 2115.1.1 apply to the agency jurisdictions identified in those sections (DSA and OSHPD). Municipal projects not under those agencies follow Chapter 21 as adopted locally; always check which adopting agency and amendments apply to your project.
More in California Building Code
- Administration & Permits
- Energy Efficiency
- Existing Buildings
- Occupancy Classification & Use
- Hazardous Materials & Occupancies
- Types of Construction
- Fire-Resistance & Fire Safety
- Interior Finishes
- Means of Egress
- Accessibility
- Exterior Walls
- Roofing & Roof Assemblies
- Structural Design
- Special Inspections & Tests
- Foundations & Soils
- Concrete
- Masonry
- Steel
- Wood
- Elevators & Conveying Systems
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