CBC · California Building Code

Shear walls, diaphragms and lateral force‑resisting system rules

In plain terms: the CBC requires wood shear walls and diaphragms to be designed per the AWC SDPWS and the CBC rules — show and reinforce any openings, check diaphragm stiffness using the CBC equation, and use the CBC tables for allowable shear only where the project conditions exactly match the table (and are allowed in your seismic category).

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

Wood shear walls and wood diaphragms used to resist wind or seismic loads must be designed and constructed in accordance with the AWC SDPWS standard and the applicable CBC provisions; the CBC explicitly requires designers to follow § 2305.1 for scope and design direction. Openings that materially reduce shear panel strength must be shown and edge‑reinforced on the plans (§ 2305.1.1). Diaphragm deflection must be calculated per the formula in § 2305.2, and shear wall allowable shear capacities and fastener rules are given in the 2306.3 tables and notes (§ 2306.3).

Requirements in detail

Design standard and scope

  • Use AWC SDPWS for design and construction when wood shear walls or wood diaphragms resist wind or seismic loads, as required by § 2305.1. The CBC references that standard as the controlling design document for these systems.

Openings in shear panels

  • Any opening that materially affects shear-panel strength must be detailed on the plans and the edges must be reinforced to transfer shearing stresses, per § 2305.1.1. This means show the opening geometry and the detail (blocking, straps, framed edges, additional panel, etc.) that carries shear around the opening.

Load‑duration adjustments for lateral-only permanent loads

  • If a wood shear wall or diaphragm is being designed for lateral loads of permanent load duration only (not combined with wind or seismic), the CBC requires reduction factors on the nominal unit shear capacities from AWC SDPWS: multiply nominal unit shear capacities by 0.2 for ASD (see § 2306) and by 0.3 for LRFD (see § 2307). This provision is in § 2305.1.2.

Diaphragm deflection — how to evaluate stiffness and drift

  • Diaphragm deflection of wood‑frame diaphragms must be determined in accordance with AWC SDPWS, and a specific diaphragm deflection equation is provided in § 2305.2 (Equation 23‑1). The code gives a four‑term expression for Δdia that includes bending of chords, shear of the diaphragm, a term for end‑anchorage/deformation and a term for concentrated collector/connector deformations; designers must use the equation (or an approved alternate) when calculating diaphragm drift and compatibility. § 2305.2 lists the governing equation and variable definitions.

(Excerpted requirement: diaphragm deflection may be calculated with the CBC's Equation 23‑1 when the diaphragm is blocked and uniformly fastened; if not uniformly fastened, the code requires modification of a constant by an approved method — see § 2305.2.)

Shear wall allowable shear values and fastener rules (selection summary)

  • § 2306.3 includes tabulated allowable shear values for shear walls (by sheathing type, thickness, fastener type and edge spacing). The tables give the decision‑relevant shear capacity per linear foot for typical panel/thickness/fastener combinations and include notes restricting use in higher seismic design categories and giving species and backing conditions. See § 2306.3 and Table 2306.3(2) for staple‑fastened fiberboard examples and their allowable shear values.

Table — selected decision values from CBC Table 2306.3(2) (examples)

Panel / Fastener Staple / edge spacing Allowable shear (plf) Code Reference
1/2" or 25/32" Structural panel — No. 16 gage, 7/16" crown, 1 3/4" long staple 4 in. 150 plf § 2306.3 (Table 2306.3(2))
1/2" or 25/32" Structural panel — No. 16 gage, 1" crown, 1 3/4" long staple 3 in. 290 plf § 2306.3 (Table 2306.3(2))
1/2" or 25/32" Structural panel — No. 16 gage, 1" crown, 1 3/4" long staple 2 in. 325 plf § 2306.3 (Table 2306.3(2))

Notes pulled from the table: values are for fiberboard sheathing on one side only, panel edges must be backed with at least 2‑inch framing of certain species or adjusted by species factor, and the table values are not permitted in Seismic Design Categories D, E or F (see the table notes).

Exceptions & special cases

  • The CBC explicitly permits the use of the SDPWS provisions with California modifications; special jurisdictional modifications (for DSA and OSHPD applications) are noted in § 2305.1.3 — check those if your project is under those agencies.
  • When diaphragm fasteners are not uniform, § 2305.2 requires the 0.188 constant in the equation be modified by an approved method (i.e., you cannot blindly apply the uniform‑fastening form of the equation to nonuniform conditions).
  • Some state agency rules prohibit certain systems in their jurisdiction (for example, Section 2301.1.5 lists certain prohibited methods for DSA/OSHPD applications — e.g., straight‑sheathed horizontal lumber diaphragms and certain staple‑fastened panel systems are listed there). If your project is subject to DSA/OSHPD, review § 2301.1.5.
  • Table entries sometimes explicitly prohibit use in Seismic Design Categories D, E or F; the table footnotes must be checked before adopting tabulated values for a high‑seismic project.

Common mistakes

  • Not referencing AWC SDPWS (the code‑required standard) for shear wall and diaphragm design — § 2305.1 requires use of SDPWS.
  • Failing to show and detail openings in shear panels on the plans (omitting the required edge reinforcement/detail per § 2305.1.1).
  • Applying tabulated allowable values in a Seismic Design Category where the table notes forbid their use (see Table 2306.3(2) notes).
  • Using the diaphragm deflection simplified equation for diaphragms that are not uniformly fastened without modifying the constant/term as required by § 2305.2.
  • Assuming permanent‑load‑only reductions apply to wind/seismic combinations (they do not — § 2305.1.2 addresses permanent‑load‑only cases).

Worked example — using the table to size a short shear wall

Scenario: You have a short shear wall with 8 ft of wall length and you plan to use 1/2" structural fiberboard sheathing fastened with No.16 gage staples, 1" crown, 1 3/4" long, with edges at 3" spacing. From Table 2306.3(2) the allowable shear is 290 plf for that combination. § 2306.3 (Table 2306.3(2)) provides this value.

  • Wall shear capacity = allowable shear (plf) × length
  • = 290 lb/ft × 8 ft = 2,320 lb

Interpretation: that 8‑ft wall, as constructed in the example, resists 2,320 lb of in‑plane shear (per the table). If your design shear demand at that wall is greater than 2,320 lb you must (a) increase panel edge fastener density, (b) change panel/fastener type to a higher‑capacity system, or (c) provide additional wall length/collector capacity. Always verify that the table may be used for your Seismic Design Category (some table values are not permitted in SDC D, E or F).

Related provisions

  • § 2305 — General design requirements for lateral force‑resisting systems (reference to AWC SDPWS and general scope)
  • § 2305.1 — General (use of AWC SDPWS; openings; load‑duration adjustments)
  • § 2305.2 — Diaphragm deflection (Equation 23‑1 and required procedure)
  • § 2306.3 — Shear walls (tables of allowable shear values and fastener/spacing rules)
  • § 2301.1.5 — State‑agency prohibitions and modifications relevant to seismic force‑resisting systems (DSA/OSHPD notes)
  • § 1705A.13.2 (special inspection for structural wood in seismic force‑resisting systems) — special inspection requirements for wood shear walls and diaphragms in high SDCs.

Code references

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

  • CBC § 23-25 High relevance — show source text

    2305 General Design Requirements for Lateral Force-Resisting Systems. . . . . . . . . . . . . . . . . . . . .23-25

    2306 Allowable Stress Design . . . . . . . . . . . . . . . . . . . . . . .23-27

    2307 Load and Resistance Factor Design. . . . . . . . . . . . .23-32

    2308 Conventional Light-Frame Construction . . . . . . . .23-32

    2309 Wood Frame Construction Manual . . . . . . . . . . . . .23-80

    CHAPTER 24 GLASS AND GLAZING . . . . . . . . . . . . . . . . . . .24-1

    2401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24-3

    2402 Glazing Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . 24-3

    2403 General Requirements for Glass . . . . . . . . . . . . . . . . . 24-3

    2404 Wind, Snow, Seismic and Dead Loads on Glass . . . 24-4

    2405 Sloped Glazing and Skylights . . . . . . . . . . . . . . . . . . . 24-6

    2406 Safety Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24-7

    2407 Glass in Handrails and Guards . . . . . . . . . . . . . . . . . . 24-9

    2408 Glazing in Athletic Facilities. . . . . . . . . . . . . . . . . . . .24-10

    2409 Glass in Walkways, Elevator Hoistways and Elevator Cars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24-10

    2410 [DSA-SS, DSA-SS/CC, OSHPD 1, 1R, 2, 4 & 5] Structural Sealant Glazing (SSG) . . . . . . . . . . . . . . 24-11

    2411 [OSHPD 1, 1R, 2, 4 & 5] Thermal Barriers in Aluminum Mullion Systems . . . . . . . . . . . . . . . . . . . 24-12

    CHAPTER 25 GYPSUM PANEL PRODUCTS AND

    PLASTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25-1

    2501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-3

    2502 Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-3

  • CBC § 2304.12.9 High relevance — show source text

    2304.12.9 Earth fills. [SPCB] Separate the earth fills such as under porches or paving from all woodwork by concrete, masonry, good quality cement plaster or other material approved by local building codes. Chemical treatment of earth fills is considered adequate if the foundation adjoining the fill meets standards of the current building codes.

    2304.13 Long-term loading. Wood members supporting concrete, masonry or similar materials shall be checked for the effects of long-term loading using the provisions of the ANSI/AWC NDS. The total deflection, including the effects of long-term loading, shall be limited in accordance with Section 1604.3.1 for these supported materials.

    Exception: Horizontal wood members supporting masonry or concrete nonstructural floor or roof surfacing not more than 4 inches (102 mm) thick need not be checked for long-term loading.

    SECTION 2305—GENERAL DESIGN REQUIREMENTS FOR LATERAL FORCE-RESISTING SYSTEMS

    2305.1 General. Structures using wood shear walls or wood diaphragms to resist wind or seismic loads shall be designed and constructed in accordance with AWC SDPWS and the applicable provisions of Sections 2305, 2306 and 2307.

    2305.1.1 Openings in shear panels. Openings in shear panels that materially affect their strength shall be detailed on the plans and shall have their edges adequately reinforced to transfer all shearing stresses.

    2305.1.2 Permanent load duration. Permanent loads are associated with permanent load duration in accordance with the ANSI/AWC NDS. For wood shear walls and wood diaphragms designed to resist lateral loads of permanent load duration only and that are not in combination with wind or seismic lateral loads, the design unit shear capacities shall be taken as the AWC SDPWS nominal unit shear capacities, multiplied by 0.2 for use with allowable stress design in Section 2306 and 0.3 for use with load and resistance factor design in Section 2307.

    2305.1.3 Additional requirements. [DSA-SS, DSA-SS/CC, OSHPD 1, 1R, 2, 4 & 5] See Section 2301.1.5 for modifications to AWC SDPWS.

    2305.2 Diaphragm deflection. The deflection of wood-frame diaphragms shall be determined in accordance with AWC SDPWS. The deflection (Δ dia ) of a blocked wood structural panel diaphragm uniformly fastened throughout with staples is permitted to be calculated in accordance with Equation 23-1. If not uniformly fastened, the constant 0.188 (For SI: 1/1627) in the third term shall be modified by an approved method. Equation 23-1 Δ dia = 5 vL [3] /8 EAW + vL /4 Gt + 0.188 Le n + Σ( x Δ c )/2 W For SI: Δ dia = 0.052 vL [3] / EAW + vL /4 Gt + Le n /1627 + Σ( x Δ c )/2 W

    where:

    A = Area of chord cross section, in square inches (mm [2] ). E = Modulus of elasticity of diaphragm chords, in pounds per square inch (N/mm [2] ).

  • CBC § 2303.1.7 High relevance — show source text

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    INDEX

    Hardboard 2303.1.7 Heavy timber construction 602.4, 2304.11

    Hurricane shutters 1609.2

    I-joist 2303.1.2 Inspection, special 1705.12.1, 1705.13.2, 1705.5 Lateral force-resisting systems 2305 Light-frame construction, conventional 2308 Load and resistance factor design 2307

    Moisture content 2303.1.9.2, 2303.2.9, 2303.7, 2304.9.5.1, Table 2305.2(1), Table 2305.2(2) Nails and staples 2303.6 Plywood, hardwood 2303.3 Preservative treated 1402.6, 1402.9,

    2303.1.9 Roof framing (see Roof Construction, Wood)

    2304.4 Roof sheathing 2304.8 Seismic provisions 2305, 2306, 2308.10.10, 2308.10.6, 2308.10.8 Shear walls 2305, 2306.3 Standards and quality, minimum 2303 Structural panels 2303.1.5 Supporting concrete or masonry 2304.13 Termite, protection against 2304.12 Trusses 2303.4

    Veneer Chapter 14 Wall framing (see Wall, Wood Construction)

    2304.3 Wall sheathing, exterior 2304.6 Wood Frame Construction Manual

    2309 Wood Shingles and Shakes 1507.8, 1507.9 Wood Structural Panels (see Wood) 2303.1.5 Bracing 2308.10 Decorative 2303.3 Diaphragms 2305.2, 2306.2 Fastening 2304.10 Fire-retardant-treated 2303.2 Quality 2303.1.5 Roof sheathing 2304.8, 2308.11.9 Seismic shear panels 2305.1, 2308.10.6.2

    Shear walls 2306.3 Sheathing 2304.6.1 Standards 2306.1

    Subfloors 805.1.1

    Veneer 1404.6

    Yards or Courts 1201.1, 1205 Exit discharge 1027.4, 1029.1 Group I-2 407.10 Group I-3 408.3.6, 408.6.2 Light, natural 1204 Occupant load 1004.7 Parking garage, open 406.5.5 Unlimited area building 507.2, 507.2.1

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    HISTORY NOTE APPENDIX

    2025 California Building Code California Code of Regulations, Title 24, Part 2 Volume 1

    HISTORY:

  • CBC § 2308.10 High relevance — show source text

    walls 2308.10 Calculated fire resistance 722.6 Ceiling framing 2308.11 Connectors and fasteners 2304.10,

    2308.5

    Contacting concrete, masonry or earth 2304.12.1.3, 2304.12.1.4, 2304.12.2.1, 2304.12.2.2, 2304.12.2.6 Cross-laminated timber 2301.2, 2303.1, 2303.1.4, 2304.11.2.1, 2304.11.3.1, 2304.11.4.1 Cutting, notching and boring of dimensional wood framing 2308.6 Decay, protection against 2304.12 Diaphragms 2305.1, 2305.2, 2306.2 Dimensions 2301.2 Draftstopping 718.3, 718.4 End-jointed lumber 2303.1.1.2 Fiberboard 2303.1.6, Table 2306.3(2) Fireblocking 718.2 Fire-retardant treated 2303.2 Floor and roof framing (see Floor Construction, Wood) 2304.4 Floor sheathing 2304.8 Foundation 1807.1.4, 2304.10.6.2, 2304.12.1.2, 2308.10.8.1, 2308.7 Grade, lumber 2303.1.1

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    INDEX

    Hardboard 2303.1.7 Heavy timber construction 602.4, 2304.11

    Hurricane shutters 1609.2

    I-joist 2303.1.2 Inspection, special 1705.12.1, 1705.13.2, 1705.5 Lateral force-resisting systems 2305 Light-frame construction, conventional 2308 Load and resistance factor design 2307

    Moisture content 2303.1.9.2, 2303.2.9, 2303.7, 2304.9.5.1, Table 2305.2(1), Table 2305.2(2) Nails and staples 2303.6 Plywood, hardwood 2303.3 Preservative treated 1402.6, 1402.9,

    2303.1.9 Roof framing (see Roof Construction, Wood)

    2304.4 Roof sheathing 2304.8 Seismic provisions 2305, 2306, 2308.10.10, 2308.10.6, 2308.10.8 Shear walls 2305, 2306.3 Standards and quality, minimum 2303 Structural panels 2303.1.5 Supporting concrete or masonry 2304.13 Termite, protection against 2304.12 Trusses 2303.4

    Veneer Chapter 14 Wall framing (see Wall, Wood Construction)

    2304.3 Wall sheathing, exterior 2304.6 Wood Frame Construction Manual

  • CBC § 2.5.4. High relevance — show source text

    agency. 2. Rooftop or other supported structures not exceeding two stories in height and 10 percent of the total struc- ture weight can use the systems in this section when designed as components per ASCE 7, Chapter 13. 3. Systems listed in this section can be used for seismically isolated buildings when permitted by ASCE 7, Section 17.2.5.4.

    1617.12.3 ASCE 7, Section 12.2.5.6.1. The exception in Item a is not permitted by DSA-SS/CC.

    1617.12.4 ASCE 7, Section 12.2.5.7.1. The exception in Item a is not permitted by DSA-SS/CC.

    1617.12.5 ASCE 7, Section 12.2.5.7.2. The exception in Item a is not permitted by DSA-SS/CC.

    1617.12.6 ASCE 7, Section 12.3.3.1. Replace ASCE 7, Section 12.3.3.1 by the following:

    12.3.3.1 Prohibited vertical irregularities for Seismic Design Categories D through F. Structures assigned to Seismic Design Category E or F that have vertical irregularities Type 1b, 4a or 4b of Table 12.3-2 shall not be permitted. Structures assigned to Seismic Design Category D having vertical irregularity Type 1b or 4b of Table 12.3-2 shall not be permitted.

    Exception: Structures assigned to Seismic Design Category E or F that have vertical irregularity Type 4a shall be permitted where the story lateral strength is not less than 80 percent of that in the story above.

    1617.12.7 ASCE 7, Section 12.7.2. Modify ASCE 7, Section 12.7.2 by adding Item 7 to read as follows: 7. Where buildings provide lateral support for walls retaining earth, and the exterior grades on opposite sides of the building differ by more than 6 feet (1829 mm), the load combination of the seismic increment of earth pressure due to earthquake acting on the higher side, as determined by a Geotechnical engineer qualified in soils engineering, plus the difference in earth pressures shall be added to the lateral forces provided in this section.

    1617.12.8 ASCE 7, Section 12.10.2.1. Replace Exception to ASCE 7, Section 12.10.2.1 by the following:

    Exception: In light-frame structures or portions thereof braced entirely by wood light-frame shear walls, collector elements and their connections, including connections to vertical elements, need only be designed to resist forces using the load combinations of Section 2.3.6 with seismic forces determined in accordance with Section 12.10.1.1.

    1617.12.9 ASCE 7, Section 12.13.1. Modify ASCE 7, Section 12.13.1 by adding Section 12.13.1.1 as follows:

  • 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 § 2304.12.2.6.1 High relevance — show source text

    2304.12.2.6.1 Posts or columns. Posts and columns that are supporting permanent structures and embedded in concrete that is exposed to the weather or in direct contact with the earth shall be of preservative-treated wood.

    2304.12.2.7 Termite protection. In geographical areas where hazard of termite damage is known to be very heavy, wood floor framing in the locations specified in Section 2304.12.1.1 and exposed framing of exterior decks or balconies shall be of naturally durable species (termite resistant) or preservative treated in accordance with AWPA U1 for the species, product preservative and end use or provided with approved methods of termite protection.

    2304.12.2.8 Wood used in retaining walls and cribs. Wood installed in retaining or crib walls shall be preservative treated in accordance with AWPA U1 for soil and freshwater use.

    2304.12.3 Attic ventilation. For attic ventilation, see Section 1202.2.2.

    2304.12.4 Under-floor ventilation (crawl space). For under-floor ventilation (crawl space), see Section 1202.4.

    2304.12.8 Separate wood framing. [SPCB] Correct the conditions in frame and stucco walls and similar appurtenant construction so that the wood framing is separate from the main structure by a complete concrete or masonry plug with no voids that will allow infestations to enter the structure from the wall. If there is no plug, the foundation shall be 2 inches (51 mm) or more above the grade levels and at least as high as the adjoining slabs or 4-inch (102 mm) concrete barrier seat off installed.

    2304.12.9 Earth fills. [SPCB] Separate the earth fills such as under porches or paving from all woodwork by concrete, masonry, good quality cement plaster or other material approved by local building codes. Chemical treatment of earth fills is considered adequate if the foundation adjoining the fill meets standards of the current building codes.

    2304.13 Long-term loading. Wood members supporting concrete, masonry or similar materials shall be checked for the effects of long-term loading using the provisions of the ANSI/AWC NDS. The total deflection, including the effects of long-term loading, shall be limited in accordance with Section 1604.3.1 for these supported materials.

    Exception: Horizontal wood members supporting masonry or concrete nonstructural floor or roof surfacing not more than 4 inches (102 mm) thick need not be checked for long-term loading.

    SECTION 2305—GENERAL DESIGN REQUIREMENTS FOR LATERAL FORCE-RESISTING SYSTEMS

    2305.1 General. Structures using wood shear walls or wood diaphragms to resist wind or seismic loads shall be designed and constructed in accordance with AWC SDPWS and the applicable provisions of Sections 2305, 2306 and 2307.

    2305.1.1 Openings in shear panels. Openings in shear panels that materially affect their strength shall be detailed on the plans and shall have their edges adequately reinforced to transfer all shearing stresses.

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

    Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    1705 A .13.1.2 Structural steel elements. Special inspections of structural steel elements in the seismic force-resisting systems of buildings and structures assigned to Seismic Design Category D, E or F other than those covered in Section 1705 A .13.1.1, including struts, collectors, chords and foundation elements, shall be performed in accordance with the quality assurance requirements of AISC 341 and this code .

    [DSA-SS, DSA-SS/CC] Quality assurance application is not permitted for the following AISC 341, Chapter J Sections: 1. J6 (Inspection Tasks). 2. J7 (Welding Inspection and Nondestructive Testing). 3. J10 (Inspection of Composite Structures). 4. J11 (Inspection of H-Piles).

    Additionally, the applicable portions in Table 1705A.2.1 of the California Building Code shall apply.

    1705 A .13.2 Structural wood. For the seismic force-resisting systems of structures assigned to Seismic Design Category D, E or F:

    1. Continuous special inspection shall be required during field gluing operations of elements of the seismic force-resisting system.
    2. Periodic special inspection shall be required for nailing, bolting, anchoring and other fastening of elements of the seismic force-resisting system, including wood shear walls, wood diaphragms, drag struts, braces, shear panels and hold-downs.

    1705 A .13.3 Cold-formed steel light-frame construction. For the seismic force-resisting systems of structures assigned to Seismic Design Category D, E or F, periodic special inspection shall be required for both:

    1. Welding operations of elements of the seismic force-resisting system.
    2. Screw attachment, bolting, anchoring and other fastening of elements of the seismic force-resisting system, including shear walls, braces, diaphragms, collectors (drag struts) and hold-downs.

    [DSA-SS, DSA-SS/CC] Requirements specified in Section 1705A.2.9 shall also apply.

    1705 A .13.4 Special inspection for special seismic certification . For structures assigned to Seismic Design Category D, E or F, the special inspector shall examine equipment and components requiring special seismic certification in accordance with Section 1705A.14.3 or ASCE 7 , Section 13.2.3 and verify that the label, anchorage and mounting conform to the certificate of compliance.

    1705 A .13.5 Architectural components. Periodic special inspection is required for the erection and fastening of exterior cladding, interior and exterior nonbearing walls, ceilings and interior and exterior veneer in structures assigned to Seismic Design Category D, E or F.

    [OSHPD 1] E x ception: Periodic special inspection is not required where continuous inspection of the work is performed in accor- dance with Section 7-145 of the CAC .

    1705 A .13.5.1 Access floors. Periodic special inspection is required for the anchorage of access floors in structures assigned to Seismic Design Category D, E or F.

  • CBC § 0.080 High relevance — show source text

    1/4″|4d casing (11/2″ × 0.080″); or
    4d finish (11/2″ × 0.072″)|6|12| |41.3/8″|6d casing (2″ × 0.099″); or
    6d finish (2″ × 0.092″)
    (Panel supports at 24 inches)|6|12| |For SI: 1 inch = 25.4 mm.
    a. Nails spaced at 6 inches at intermediate supports where spans are 48 inches or more. For nailing of wood structural panel and particleboard diaphragms and shear walls, refer
    to Section 2305. Nails for wall sheathing are permitted to be common, box or casing.
    b. Spacing shall be 6 inches on center on the edges and 12 inches on center at intermediate supports for nonstructural applications. Panel supports at 16 inches (20 inches if
    strength axis in the long direction of the panel, unless otherwise marked).
    c. Where a rafter is fastened to an adjacent parallel ceiling joist in accordance with this schedule and the ceiling joist is fastened to the top plate in accordance with this schedule,
    the number of toenails in the rafter shall be permitted to be reduced by one nail.
    d. RSRS is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667.
    e. Tabulated fastener requirements apply where the basic wind speed,V, is less than 140 mph. For wood structural panel roof sheathing attached to gable-end roof framing and
    to intermediate supports within 48 inches of roof edges and ridges, nails shall be spaced at 4 inches on center where the basic wind speed,V, is greater than 130 mph in Expo-
    sure B or greater than 110 mph in Exposure C. Spacing exceeding 6 inches on center at intermediate supports shall be permitted where the fastening is designed per the AWC
    NDS. Where the specific gravity of the wood species used for roof framing is greater than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, fastening of roof
    sheathing shall be with RSRS-03 (21/2″ × 0.131″ × 0.281″ head) nails unless alternative fastening is designed in accordance with AWC NDS. Where the specific gravity of the wood
    species used for roof framing is less than 0.35, fastening of the roof sheathing shall be designed in accordance with AWC NDS.
    f. Fastening is only permitted where the basic wind speed,V, is less than or equal to 110 mph and where fastening is to wood framing of a species with specific gravity greater
    than or equal to 0.42 in accordance with AWC NDS.
    g. Nails and staples are carbon steel meeting the specifications of ASTM F1667. Connections using nails and staples of other materials, such as stainless steel, shall be designed
    by acceptable engineering practice or approved under Section 104.2.3.|For SI: 1 inch = 25.4 mm.
    a. Nails spaced at 6 inches at intermediate supports where spans are 48 inches or more. For nailing of wood structural panel and particleboard diaphragms and shear walls, refer
    to Section 2305. Nails for wall sheathing are permitted to be common, box or casing.
    b. Spacing shall be 6 inches on center on the edges and 12 inches on center at intermediate supports for nonstructural applications.

  • CBC § 104.2.3. High relevance — show source text

    Connections using nails and staples of other materials, such as stainless steel, shall be designed
    by acceptable engineering practice or approved under Section 104.2.3.|For SI: 1 inch = 25.4 mm.
    a. Nails spaced at 6 inches at intermediate supports where spans are 48 inches or more. For nailing of wood structural panel and particleboard diaphragms and shear walls, refer
    to Section 2305. Nails for wall sheathing are permitted to be common, box or casing.
    b. Spacing shall be 6 inches on center on the edges and 12 inches on center at intermediate supports for nonstructural applications. Panel supports at 16 inches (20 inches if
    strength axis in the long direction of the panel, unless otherwise marked).
    c. Where a rafter is fastened to an adjacent parallel ceiling joist in accordance with this schedule and the ceiling joist is fastened to the top plate in accordance with this schedule,
    the number of toenails in the rafter shall be permitted to be reduced by one nail.
    d. RSRS is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667.
    e. Tabulated fastener requirements apply where the basic wind speed,V, is less than 140 mph. For wood structural panel roof sheathing attached to gable-end roof framing and
    to intermediate supports within 48 inches of roof edges and ridges, nails shall be spaced at 4 inches on center where the basic wind speed,V, is greater than 130 mph in Expo-
    sure B or greater than 110 mph in Exposure C. Spacing exceeding 6 inches on center at intermediate supports shall be permitted where the fastening is designed per the AWC
    NDS. Where the specific gravity of the wood species used for roof framing is greater than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, fastening of roof
    sheathing shall be with RSRS-03 (21/2″ × 0.131″ × 0.281″ head) nails unless alternative fastening is designed in accordance with AWC NDS. Where the specific gravity of the wood
    species used for roof framing is less than 0.35, fastening of the roof sheathing shall be designed in accordance with AWC NDS.
    f. Fastening is only permitted where the basic wind speed,V, is less than or equal to 110 mph and where fastening is to wood framing of a species with specific gravity greater
    than or equal to 0.42 in accordance with AWC NDS.
    g. Nails and staples are carbon steel meeting the specifications of ASTM F1667. Connections using nails and staples of other materials, such as stainless steel, shall be designed
    by acceptable engineering practice or approved under Section 104.2.3.|For SI: 1 inch = 25.4 mm.
    a. Nails spaced at 6 inches at intermediate supports where spans are 48 inches or more. For nailing of wood structural panel and particleboard diaphragms and shear walls, refer
    to Section 2305. Nails for wall sheathing are permitted to be common, box or casing.
    b. Spacing shall be 6 inches on center on the edges and 12 inches on center at intermediate supports for nonstructural applications. Panel supports at 16 inches (20 inches if
    strength axis in the long direction of the panel, unless otherwise marked).
    c.

  • CBC § 2306.3 High relevance — show source text
    TABLE 2306.3(2)—ALLOWABLE SHEAR VALUES (plf) FOR WIND OR SEISMIC LOADING ON SHEAR WALLS OF
    FIBERBOARD SHEATHING BOARD CONSTRUCTION UTILIZING STAPLES FOR TYPE V CONSTRUCTION ONLYa, b, c, d, e    		 Col2 Col3 Col4 Col5
    THICKNESS AND GRADE
    (inches)    		 STAPLE GAGE AND DIMENSIONS ALLOWABLE SHEAR VALUE (pounds per linear foot)
    STAPLE SPACING AT PANEL EDGES (inches)a    		 ALLOWABLE SHEAR VALUE (pounds per linear foot)
    STAPLE SPACING AT PANEL EDGES (inches)a    		 ALLOWABLE SHEAR VALUE (pounds per linear foot)
    STAPLE SPACING AT PANEL EDGES (inches)a
    THICKNESS AND GRADE
    (inches)    		 STAPLE GAGE AND DIMENSIONS 4 3 2
    1/2 or25/32 Structural No. 16 gage galvanized staple,
    7/16″ crown 13/4 inches long    		 150 200 225
    1/2 or25/32 Structural No. 16 gage galvanized staple,
    1″ crown 13/4 inches long    		 220 290 325
    For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
    a. Fiberboard sheathing shall not be used to brace concrete or masonry walls.
    b. Panel edges shall be backed with 2-inch or wider framing of Douglas Fir-larch or Southern pine. For framing of other species: (1) Find specific gravity for species of framing
    lumber in ANSI/AWC NDS. (2) For staples, multiply the shear value from the table by 0.82 for species with specific gravity of 0.42 or greater, or 0.65 for all other species.
    c. Values shown are for fiberboard sheathing on one side only with long panel dimension either parallel or perpendicular to studs.
    d. Fastener shall be spaced 6 inches on center along intermediate framing members.
    e. Values are not permitted in_Seismic Design Category_ D, E or F.    		 For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
    a. Fiberboard sheathing shall not be used to brace concrete or masonry walls.
    b. Panel edges shall be backed with 2-inch or wider framing of Douglas Fir-larch or Southern pine. For framing of other species: (1) Find specific gravity for species of framing
    lumber in ANSI/AWC NDS. (2) For staples, multiply the shear value from the table by 0.82 for species with specific gravity of 0.42 or greater, or 0.65 for all other species.
    c. Values shown are for fiberboard sheathing on one side only with long panel dimension either parallel or perpendicular to studs.
    d. Fastener shall be spaced 6 inches on center along intermediate framing members.
    e. Values are not permitted in_Seismic Design Category_ D, E or F.    		 For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
    a.

Frequently asked questions

Are staples permitted to fasten shear panels?

Staples appear in the CBC tabulated values (see Table 2306.3(2)), but their use is subject to the table notes and Seismic Design Category restrictions — some table values are explicitly not permitted in SDC D, E or F. Also, specific state agencies (DSA/OSHPD) list prohibitions for certain staple‑fastened systems in § 2301.1.5; check project jurisdiction.

How must openings in shear panels be shown?

Openings that materially affect shear panel strength must be detailed on the plans and have edges reinforced to transfer shearing stresses (this is required by § 2305.1.1).

When can I use the tabulated shear values instead of engineering calculations?

You may use the CBC tabulated allowable shear values in § 2306.3 when the construction exactly matches the table conditions (panel type, thickness, fastener, spacing, backing/species, SDC limitations, etc.). If your conditions differ or if tabulated values are prohibited in your SDC, use engineered design in accordance with AWC SDPWS.

Do I have to calculate diaphragm deflection?

Yes — diaphragm deflection must be determined in accordance with AWC SDPWS and the CBC provides Equation 23‑1 in § 2305.2 for blocked, uniformly fastened wood structural panel diaphragms; if fasteners are not uniform you must modify the equation constant by an approved method.

How are reductions applied for permanent‑load‑only lateral design?

For wood shear walls and diaphragms designed for lateral loads of permanent load duration only (not combined with wind or seismic), the nominal unit shear capacities from AWC SDPWS are multiplied by 0.2 for ASD and by 0.3 for LRFD, per § 2305.1.2.

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