CBC · California Building Code
Sheathing, decking and panel application requirements (nailing, span, orientation)
For homeowners: the CBC prescribes where panels must bear, how to orient them (strength axis parallel or perpendicular to supports), and different nail spacing at panel edges versus the field (typical schedules: 6" o.c. edges / 12" o.c. field for many panels). Lumber decking has specific layup patterns and cantilever limits. High‑wind areas, framing wood species and special decking (T&G, laminated) change spacing or nail type — always check §§ 2304.8, 2304.9.2 and 2304.10 and the associated tables for the exact numbers and notes.
Last reviewed: July 5, 2026
What the code requires
The California Building Code requires that structural floor and roof sheathing be designed to the general provisions of Chapter 23 and that installation (panel orientation, layup pattern, fastener type and spacing, and allowable spans) follow the prescriptive schedules and patterns in §§ 2304.8, 2304.9.2 and 2304.10. The code gives specific layup patterns for lumber decking, nail/fastener schedules for wood structural panels and sheathing, and orientation/span rules (for example, panel strength axis must be parallel or perpendicular to supports) — see § 2304.8, § 2304.9.2 and § 2304.10 for the controlling requirements.
Requirements in detail
Scope and materials
- Structural floor and roof sheathing must be designed in accordance with the general provisions of the Code; prescriptive compliance is available by meeting the tables listed in § 2304.8.
- Lumber decking must follow the permitted layup patterns defined in § 2304.9.2 (simple span, two-span continuous, combination, cantilevered intermixed, or controlled random).
- Wall sheathing and wood structural panels used as braced sheathing must be fastened per the schedules in § 2304.10 and its Table references.
Panel orientation and strength axis
- Panels (wood structural panels) shall be installed with the panel strength axis either parallel or perpendicular to the supports. The Code explicitly requires the panel strength axis orientation to be parallel or perpendicular to the framing supports; certain panel/spacing combinations require the strength axis perpendicular to supports (see note in the table references).
Layup patterns for lumber decking (key points from § 2304.9.2)
- Five standard layup patterns are permitted: simple span, two-span continuous, combination simple/continuous, cantilevered pieces intermixed, and controlled random. Each pattern has specific bearing and end-joint rules (for example, controlled random requires end-joint spacing and bearing conditions).
Fasteners, spacing, and special fastener rules
- Fastener spacing for wood structural panels used for sheathing/braced walls typically follows the Table/Table 2304.10.2 schedule (for example, WSP — wood structural panel — commonly shows 6 inches o.c. at panel edges and 12 inches o.c. in the field). The Code lists fastener types and spacing in the prescriptive tables.
- For some thin panels (3/8" and 7/16") installed on studs at 24" o.c., fasteners along intermediate framing members are limited to 6" o.c.; other conditions or thicker panels often allow up to 12" o.c. at intermediate supports — see the panel fastener notes.
- Roof sheathing tables include wind-related notes: where basic wind speeds exceed certain thresholds or near gable edges, edge/intermediate nail spacings are reduced (e.g., nails at 4" o.c. near edges where V > 130 mph in Exposure B or >110 mph in Exposure C) and special ring‑shank roofing nails (RSRS) are specified in some species/gravity conditions.
Mechanically laminated and sawn tongue-and-groove decking
- Mechanically laminated decking has specific nailing rules: nails connecting laminations must be at least 2.5× the lamination thickness; side nails spacing and stagger requirements depend on support spacing (≤ 48" o.c. vs > 48" o.c.), and toenailing rules are specified.
- Tongue-and-groove decking on sloped roofs must be installed with tongues up and pattern faces down; specific nailing (toenailed and face-nailed) for 2", 3" and 4" decking have prescribed nail sizes and spike/spacing requirements.
Span and deflection references
- Floor and roof panel spans and allowable deflections are given in the Table series referenced by § 2304.8. Tables include span ratings (for example, panels with span ratings such as 24/16, 24/0, wall-16, etc.), deflection limits and edge support requirements (tongue-and-groove or blocking) for panels 24" wide or wider. Where tables are used, the panel edge condition and thickness at the point of fastening control allowable span.
Decision‑relevant quick table
| Application | Typical materials / thickness | Framing spacing (o.c.) | Typical fastener spacing (edge / field) | Orientation / span notes | Code Reference |
|---|---|---|---|---|---|
| Wall — wood structural panel (WSP) | 3/8"–1/2" (per table) | 16" or 24" (per table) | 6" edges / 12" field (common prescriptive) | Panel strength axis parallel or perpendicular to supports; some span ratings require strength axis perpendicular | § 2304.10 — Table (WSP 6" edges 12" field). |
| Roof sheathing — wood structural panel | 7/16" OSB or plywood (exterior glue) | 16" or 24" (see tables) | Edge/intermediate per Table 2304.8; note: 6" at edges / 12" intermediate common; 4" near edges for high wind zones | Panels must be exterior‑glue for roof; observe wind notes and RSRS nail requirements in high wind or species‑gravity cases | § 2304.8 and table notes. |
| Floor sheathing — wood structural panel | 3/8" to 3/4" per Table 2304.8 | 16" or 24" typical | Per Table 2304.8(1–4) — spacing and tongue/groove support conditions control allowable span/deflection | Edges must be supported; tongue‑and‑groove or blocking required for some span ratings; deflection limits specified in tables | § 2304.8 and associated tables. |
| Lumber decking (solid) | 2", 3", 4" nominal decking | Support spacing per design and layup pattern | Nailing schedules vary by decking thickness and pattern (e.g., 16d, 20d, 40d etc. for specified patterns) | Layup pattern (§ 2304.9.2) controls bearing/joint staggering and cantilever limits | § 2304.9.2 & § 2304.9.3. |
(These are representative prescriptive values from the referenced CBC tables and notes. Consult the specific table cell in § 2304.8 and § 2304.10 for exact combinations of panel type, thickness and framing spacing.)
Exceptions & special cases
- Wind/exposure adjustments: For roof sheathing in high-wind locations, edge and intermediate nailing spacing is tightened (for example, nails at 4" o.c. at edges near ridges/edges when basic wind speed exceeds specified thresholds) and RSRS ring‑shank nails may be required for some species — see the wind notes to the roof‑sheathing tables.
- Specific gravity adjustment: Where the framing species specific gravity falls in a defined range, the nail spacing in the field of wall sheathing panels may be multiplied by a factor (for example, multiply field spacing by 0.67 where framing specific gravity is ≥ 0.35 but < 0.42); for species below 0.35, fastening must be engineered per the AWC NDS.
- Mechanically laminated decking and sawn T&G decking: special nailing, spike and toenail requirements apply (see § 2304.9.3 and § 2304.9.4/5).
- Panel orientation limitations: some span ratings and panel types require the panel strength axis to be perpendicular to supports — check the specific table cell and its notes.
If a particular thickness / material / framing spacing combination you plan to use is not tabulated, the Code requires design in accordance with the general provisions of Chapter 23 (engineered design) instead of the prescriptive tables.
Common mistakes
- Using the wrong fastener spacing (e.g., installing panel edge nails at field spacing or omitting the tighter edge spacing required for braced panels). The prescriptive tables require different spacing at edges vs field — don't mix them.
- Installing panel edges over unsupported joints or not providing required blocking or tongue‑and‑groove support; many span ratings assume edge support.
- Failing to orient the panel strength axis per the table/notes (some panels require strength axis perpendicular to supports).
- Ignoring wind‑zone notes and species‑specific fastening adjustments (i.e., not reducing spacing where the table’s wind note requires it or failing to apply the specific gravity multiplier).
- For lumber decking: using random layup without meeting the prescribed layup pattern details (end‑joint staggering, bearing requirements) in § 2304.9.2.
Worked example
Scenario: Exterior wall sheathing — 1/2" wood structural panel (WSP) applied to studs at 24" o.c. using the prescriptive schedule.
Step-by-step per the Code:
- Determine prescriptive applicability: 1/2" WSP is covered by the WSP rows in the panel/ sheathing tables referenced by § 2304.10. If the panel and framing combination appears in the table, the prescriptive fastener schedule applies.
- Orientation: Install the panels with the strength axis parallel or perpendicular to supports as allowed; if the table requires the strength axis perpendicular for the chosen span rating, orient accordingly.
- Fastening: For typical WSP the common prescriptive schedule is 6" o.c. at panel edges and 12" o.c. in the field for braced wall applications (use the exact table cell in § 2304.10 to confirm). So on 24" o.c. studs, edge nails at 6" o.c., field nails at 12" o.c. (use the specified nail type in the table).
- If the framing species has specific gravity between 0.35 and 0.42, multiply the field nail spacing by 0.67 (result: 12" × 0.67 ≈ 8" o.c. in the field) — i.e., reduce spacing to meet the adjustment note. If species specific gravity < 0.35, an engineered fastening design per AWC NDS is required.
This example shows how you use the table + orientation note + species‑gravity adjustment in sequence; always confirm the exact table cell in § 2304.10 and any table notes that apply to your condition.
Related provisions
- § 2304.8 — Structural floor and roof sheathing: prescriptive tables and scope.
- § 2304.9.2 — Lumber decking layup patterns (five permitted patterns and related limits).
- § 2304.10 — Panel sheathing application and fastener schedules (Table 2304.10.2 and notes).
- § 2305 — Nailing/diaphragm/shear details (see for diaphragm nailing and shear wall special fastening — consult when panels are used for lateral force resistance).
- § 2304.9.3 — Mechanically laminated decking nailing and toe‑nailing rules.
- § 2301.1.5 — Prohibitions that can affect fastening choices (e.g., staples prohibited for wood structural panel shear walls in some agency jurisdictions).
Code references
Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:
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 § 2308.11.11. High relevance — show source text
Random
layup is permitted in accordance with the provisions of Section 2308.11.11. Lumber thickness is 11/2 inches nominal.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kN/m2, 1 pound per square inch = 0.00689 N/mm2.
a. Spans are based on simple beam action with 10 pounds per square foot dead load and provisions for a 300-pound concentrated load on a 12-inch width of decking. Random
layup is permitted in accordance with the provisions of Section 2308.11.11. Lumber thickness is 11/2 inches nominal.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kN/m2, 1 pound per square inch = 0.00689 N/mm2.
a. Spans are based on simple beam action with 10 pounds per square foot dead load and provisions for a 300-pound concentrated load on a 12-inch width of decking. Random
layup is permitted in accordance with the provisions of Section 2308.11.11. Lumber thickness is 11/2 inches nominal.|�
2308.11.12 Wood trusses. Wood trusses shall be designed in accordance with Section 2303.4. Connection to braced wall lines shall be in accordance with Section 2308.10.7.2.
2308.11.13 Attic ventilation. For attic ventilation, see Section 1202.2.1.
SECTION 2309—WOOD FRAME CONSTRUCTION MANUAL
2309.1 Wood Frame Construction Manual. Structural design in accordance with the AWC WFCM shall be permitted for buildings assigned to Risk Category I or II subject to the limitations of Section 1.1.3 of the AWC WFCM and the load assumptions contained therein. Structural elements beyond these limitations shall be designed in accordance with accepted engineering practice.
2309.1.1 Additional requirements. [DSA-SS, DSA-SS/CC, OSHPD 1R, 2 & 5] The use of the AWC WFCM is permitted provided the design and construction also comply with Sections 2304, 2305 and 2302.1, Item 1 or 2, and engineering analysis is furnished demon- strating compliance.
23-80 2025 CALIFORNIA BUILDING CODE
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CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE
CHAPTER 24 – GLASS AND GLAZING
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CBC § 25.4 High relevance — show source text
Applies to panels 24 inches or wider.
b. Uniform load deflection limitations1/180 of span under live load plus dead load,1/240 under live load only.
c. Panel edges shall have approved tongue-and-groove joints or shall be supported with blocking unless1/4-inch minimum thickness underlayment or 11/2 inches of approved
cellular or lightweight concrete is placed over the subfloor, or finish floor is3/4-inch wood strip. Allowable uniform load based on deflection of1/360 of span is 100 pounds per
square foot except the span rating of 48 inches on center is based on a total load of 65 pounds per square foot.
d. Allowable load at maximum span. Where the total load includes snow, use allowable stress design snow loads.
e. Tongue-and-groove edges, panel edge clips (one midway between each support, except two equally spaced between supports 48 inches on center), lumber blocking or
other. Only lumber blocking shall satisfy blocked diaphragm requirements.
f. For1/2-inch panel, maximum span shall be 24 inches.
g. Span is permitted to be 24 inches on center where3/4-inch wood strip flooring is installed at right angles to joist.
h. Span is permitted to be 24 inches on center for floors where 11/2 inches of cellular or lightweight concrete is applied over the panels.|For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kN/m2.
a. Applies to panels 24 inches or wider.
b. Uniform load deflection limitations1/180 of span under live load plus dead load,1/240 under live load only.
c. Panel edges shall have approved tongue-and-groove joints or shall be supported with blocking unless1/4-inch minimum thickness underlayment or 11/2 inches of approved
cellular or lightweight concrete is placed over the subfloor, or finish floor is3/4-inch wood strip. Allowable uniform load based on deflection of1/360 of span is 100 pounds per
square foot except the span rating of 48 inches on center is based on a total load of 65 pounds per square foot.
d. Allowable load at maximum span. Where the total load includes snow, use allowable stress design snow loads.
e. Tongue-and-groove edges, panel edge clips (one midway between each support, except two equally spaced between supports 48 inches on center), lumber blocking or
other. Only lumber blocking shall satisfy blocked diaphragm requirements.
f. For1/2-inch panel, maximum span shall be 24 inches.
g. Span is permitted to be 24 inches on center where3/4-inch wood strip flooring is installed at right angles to joist.
h. Span is permitted to be 24 inches on center for floors where 11/2 inches of cellular or lightweight concrete is applied over the panels.||TABLE 2304.
CBC § 0.35 High relevance — show source text
Where the specific gravity of the wood species used for wall framing is greater than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, nail spacing in the field of
the panel shall be multiplied by 0.67. Where the specific gravity of the wood species used for wall framing is less than 0.35, fastening of the wall sheathing shall be designed in
accordance with AWC NDS.|For SI: 1 inch = 25.4 mm, 1 mile per hour = 0.447 m/s.
a. Panel strength axis shall be parallel or perpendicular to supports. Three-ply plywood sheathing with studs spaced more than 16 inches on center shall be applied with panel
strength axis perpendicular to supports.
b. The table is based on wind pressures acting toward and away from building surfaces in accordance with Section 30.4 of ASCE 7. Lateral requirements shall be in accordance
with Section 2305 or 2308.
c. Wood structural panels with span ratings of wall-16 or wall-24 shall be permitted as an alternative to panels with a 24/0 span rating. Plywood siding rated 16 on center or 24 on
center shall be permitted as an alternative to panels with a 24/16 span rating. Wall-16 and plywood siding 16 on center shall be used with studs spaced not more than 16
inches on center.
d. Where the specific gravity of the wood species used for wall framing is greater than or equal to 0.35 but less than 0.42 in accordance with AWC NDS, nail spacing in the field of
the panel shall be multiplied by 0.67. Where the specific gravity of the wood species used for wall framing is less than 0.35, fastening of the wall sheathing shall be designed in
accordance with AWC NDS.|2304.7 Interior paneling. Softwood wood structural panels used for interior paneling shall conform to the provisions of Chapter 8 and shall be installed in accordance with Table 2304.10.2. Panels shall comply with DOC PS 1, DOC PS 2 or ANSI/APA PRP 210. Prefinished hardboard paneling shall meet the requirements of ANSI A135.5. Hardwood plywood shall conform to HPVA HP-1.
2304.8 Floor and roof sheathing. Structural floor sheathing and structural roof sheathing shall comply with Sections 2304.8.1 and 2304.8.2, respectively.
CBC § 1409.7.2. High relevance — show source text
Exceptions:
Assemblies protected on the outside with one of the following:
- A thermal barrier complying with Section 1409.7.2.
- Concrete or masonry not less than 1 inch (25 mm) in thickness.
- Glass-fiber-reinforced concrete panels not less than [3] / 8 inch (9.5 mm) in thickness.
- Metal-faced panels having outer facings not less in thickness than 0.019 inch (0.48 mm) aluminum or 0.016 inch (0.41 mm) corrosion-resistant steel.
- Stucco not less than [7] / 8 inch (22.2 mm) in thickness, complying with Section 2510.
- Fiber-cement lap, panel or shingle siding complying with Section 1404.17 and Section 1404.17.1 or 1404.17.2, and having a thickness of not less than [1] / 4 inch (6.4 mm).
14-20 2025 CALIFORNIA BUILDING CODE
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EXTERIOR WALLS
1409.8 Type V construction. IMP shall be permitted for use in Type V construction.
1409.9 Labeling. Unless otherwise specified, the edge or face of each IMP or package shall bear the label of an approved agency. The label shall contain the manufacturer’s or distributor’s identification, model number, serial number or definitive information describing the product or materials’ performance characteristics and approved agency’s identification.
1409.9.1 Foam plastic core. IMP having a foam plastic core shall be labeled in accordance with Sections 2603.2 and 2603.5.6, as applicable.
SECTION 1410—PLASTIC COMPOSITE DECKING
[BS] 1410.1 Plastic composite decking. Exterior deck boards, stair treads, handrails and guards constructed of plastic composites, including plastic lumber, shall comply with Section 2612.
SECTION 1411—BUILDING-INTEGRATED PHOTOVOLTAIC (BIPV) SYSTEMS FOR EXTERIOR WALL COVERINGS AND FENESTRATION
1411.1 Listing required. In addition to complying with other provisions of this code, building-integrated photovoltaic (BIPV) systems used as exterior wall coverings or fenestration shall be listed and labeled in accordance with UL 1703 or both UL 61730-1 and UL 61730-2.
SECTION 1412—SOFFITS AND FASCIAS AT ROOF OVERHANGS
1412.1 General. Soffits and fascias at roof overhangs shall be designed and constructed in accordance with the applicable provisions of this section.
1412.2 General wind requirements. Soffits and fascias shall be capable of resisting the component and cladding loads for walls determined in accordance with Chapter 16 using an effective wind area of 10 square feet (0.93 m [2] ).
1412.3 Vinyl and aluminum soffit panels. Vinyl and aluminum soffit panels shall comply with Section 1412.2, shall be installed using fasteners specified by the manufacturer and shall be fastened at both ends to a supporting component such as a nailing strip, fascia or subfascia component in accordance with Figure 1412.3(1).
CBC § 2304.9.3.3 High relevance — show source text
Nails shall be driven perpendicular to the lamination face, alternating between top and bottom edges.
b. Where nails penetrate through two laminations and into the third, they shall be staggered one-third of the spacing in adjacent laminations. Otherwise, nails shall be stag-
gered one-half of the spacing in adjacent laminations.
c. Where supports are 48 inches on center or less, alternate laminations shall be toenailed to alternate supports; where supports are spaced more than 48 inches on center,
alternate laminations shall be toenailed to every support.|2304.9.3.3 Controlled random pattern. There shall be a minimum distance of 24 inches (610 mm) between end joints in adjacent courses. The pieces in the first and second courses shall bear on not fewer than two supports with end joints in these two courses occurring on alternate supports. Not more than seven intervening courses shall be permitted before this pattern is repeated.
2304.9.4 Two-inch sawn tongue-and-groove decking. Two-inch (51 mm) sawn tongue-and-groove decking shall comply with Sections 2304.9.4.1 through 2304.9.4.3.
2304.9.4.1 General. Two-inch (51 mm) decking shall have a maximum moisture content of 15 percent. Decking shall be machined with a single tongue-and-groove pattern. Each decking piece shall be nailed to each support.
2304.9.4.2 Nailing. Each piece of decking shall be toenailed at each support with one 16d common nail through the tongue and face-nailed with one 16d common nail.
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WOOD
2304.9.4.3 Controlled random pattern. There shall be a minimum distance of 24 inches (610 mm) between end joints in adjacent courses. The pieces in the first and second courses shall bear on not fewer than two supports with end joints in these two courses occurring on alternate supports. Not more than seven intervening courses shall be permitted before this pattern is repeated.
2304.9.5 Three- and four-inch sawn tongue-and-groove decking. Three- and four-inch (76 mm and 102 mm) sawn tongue-andgroove decking shall comply with Sections 2304.9.5.1 through 2304.9.5.3.
2304.9.5.1 General. Three-inch (76 mm) and four-inch (102 mm) decking shall have a maximum moisture content of 19 percent. Decking shall be machined with a double tongue-and-groove pattern. Decking pieces shall be interconnected and nailed to the supports.
2304.9.5.2 Nailing. Each piece shall be toenailed at each support with one 40d common nail and face-nailed with one 60d common nail. Courses shall be spiked to each other with 8-inch (203 mm) spikes at maximum intervals of 30 inches (762 mm) through predrilled edge holes penetrating to a depth of approximately 4 inches (102 mm). One spike shall be installed at a distance not exceeding 10 inches (254 mm) from the end of each piece.
CBC § 1006.2.2.1 High relevance — show source text
Exits 1006.2.2.1
Bolts
Anchor rods 1901.3 Bonding, Masonry 1805.2.2, 2103.2.2, 2113.3.1, 2510.7 Bottle-Filling Stations 202 Braced Wall Line 202
Bracing 2308.10 Seismic requirements 2308.10.10.2, 2308.10.6.2, 2308.10.8 Sill anchorage 2308.10.7.3 Spacing 2308.10.1 Support 2308.10.8 Temporary 3103.5 Braced Wall Panel 202 Alternative bracing 2308.10.5.1, 2308.10.5.2
Connections 2308.10.7 Length 2308.10.4 Location 2308.10.2
Method 2308.10.3 Brick (see Masonry) Building Area (see Area, Building) 502.1, 503, 505, 506, 507, 508, 510 Demolition 3303
Existing 101.4.7 Fire walls 706.1 Height (see Height, Building) 502.1, 503, 504, 505, 508, 510 Occupancy classification Chapter 3 Party walls 706.1.1 Relocatable 3113
Replicable Appendix N Building, Existing 202 Building Department 103 Building Official Duties and powers 103, 104 Qualifications Appendix A Records 104.7
Termination A101.4 Building-Integrated Photovoltaic (BIPV) (see Photovoltaic) Built-Up Roof 1507.10 Business Occupancy (Group B) 303.1.1, 303.1.2, 304 Alarms and detection 907.2.2 Ambulatory care facilities 304, 422 Area 503, 505, 506, 507, 508 Height 503, 504, 505, 508, 510 Higher education laboratories 428, 2702.2
Incidental uses 509 Interior finishes Table 803.13, 804 Live load Table 1607.1 Means of egress Aisles 1018.3
Stairway, exit access 1019 Travel distance 1006.3, 1017.2,
1006.2.1
Mixed occupancies 508.2, 508.3, 508.4 Accessory 303.1.2, 508.2 Ambulatory care facilities 422 Assembly 303.1.2
Assembly spaces 1030 Exit signs 1013.1 Guards 1015.2, 1030.17 Main exit 1030.3
CBC § 1502.1 High relevance — show source text
Adopting agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting agency BSC BSC-
CGSFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt entire chapter X X Adopt entire chapter as
amended (amended sections
listed below)X X X X X X X X X X Adopt only those sections
that are listed belowX Chapter / Section 1501 X 1502.1 X X 1502.2 X X 1503.3 – 1503.4 X 1505 – 1507 X 1507.3.10 X X X X X X X 1507.7.8 X X X X X X X 1509 – 1511 X 1511.9.6 X X 1511.10– 1511.10.1 X X X X X X X X X X 1512 X 1513 X X X X X X X The state agency does not adopt sections identified by 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.
2025 CALIFORNIA BUILDING CODE 15-1
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15-2 2025 CALIFORNIA BUILDING CODE
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15 ROOF ASSEMBLIES AND ROOFTOP STRUCTURES
User notes:
CBC § 0.63 Medium relevance — show source text
Staples shall have a minimum crown width of7/16 inch and shall be installed with their crowns parallel to the long dimension of the framing members.
i. For shear loads of normal or permanent load duration as defined by the ANSI/AWC NDS, the values in the table shall be multiplied by 0.63 or 0.56, respectively.|For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
a. For framing of other species: (1) Find specific gravity for species of lumber in ANSI/AWC NDS. (2) For staples find shear value from table for Structural I panels (regardless of
actual grade) and multiply value by 0.82 for species with specific gravity of 0.42 or greater, or 0.65 for all other species.
b. Panel edges backed with 2-inch nominal or wider framing. Install panels either horizontally or vertically. Space fasteners maximum 6 inches on center along intermediate
framing members for3/8-inch and7/16-inch panels installed on studs spaced 24 inches on center. For other conditions and panel thickness, space fasteners maximum 12 inches
on center on intermediate supports.
c. 3/8-inch panel thickness or siding with a span rating of 16 inches on center is the minimum recommended where applied directly to framing as exterior siding. For grooved
panel siding, the nominal panel thickness is the thickness of the panel measured at the point of fastening.
d. Framing at adjoining panel edges shall be 3 inches nominal or wider.
e. Values apply to all-veneer plywood. Thickness at point of fastening on panel edges governs shear values.
f. Where panels are applied on both faces of a wall and fastener spacing is less than 6 inches on center on either side, panel joints shall be offset to fall on different framing
members, or framing shall be 3 inches nominal or thicker at adjoining panel edges.
g. In Seismic Design Category D, E or F, where shear design values exceed 350 pounds per linear foot, all framing members receiving edge fastening from abutting panels shall be
not less than a single 3-inch nominal member, or two 2-inch nominal members fastened together in accordance with Section 2306.1 to transfer the design shear value
between framing members. Wood structural panel joint and sill plate nailing shall be staggered at all panel edges. See AWC SDPWS for sill plate size and anchorage
requirements.
h. Staples shall have a minimum crown width of7/16 inch and shall be installed with their crowns parallel to the long dimension of the framing members.
i. For shear loads of normal or permanent load duration as defined by the ANSI/AWC NDS, the values in the table shall be multiplied by 0.63 or 0.56, respectively.|For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
a. For framing of other species: (1) Find specific gravity for species of lumber in ANSI/AWC NDS. (2) For staples find shear value from table for Structural I panels (regardless of
actual grade) and multiply value by 0.82 for species with specific gravity of 0.42 or greater, or 0.65 for all other species.
b. Panel edges backed with 2-inch nominal or wider framing. Install panels either horizontally or vertically.CBC § 907.5.2.3.1 Medium relevance — show source text
Employee Accessibility for work areas 907.5.2.3.1, Chapter 11B Deputies to building official 103.3 Liability 104.8 Qualifications A101 Termination of employment A101.4 Toilet facilities Chapter 11B Encroachments Into the Public Right-of-Way Chapter 32 End-Jointed Lumber 2303.1.1.2
Relocated structures 101.4.7, D103.3 Rodentproofing Appendix F
INDEX-6 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
Energy Efficiency Chapter 13, 101.4.6, 110.3.9 Enforcing Agency 202 Housing and Community Development 1.8 Engineer (see Definition for Registered Design Professional) Entrances 905.3.3, 1030.4, Chapter 11B Equipment Countertop Equipment 202 Essential Equipment 202 Fixed Equipment 202 Interim Equipment 202 Mobile Equipment 202 Movable Equipment 202 Other Equipment 202 Temporary Equipment 202 Equipment Platform 505.3 Area limitation 505.2.1, 505.2.1.1,
505.3.1 Automatic sprinkler system 505.3.2 Equivalent Opening Factor Figure 705.8 Escalators 3004 Floor opening protection 712.1.3 Means of egress 1003.7 Essential Facilities (see Risk Category) Table 1604.5 Excavation, Grading and Fill 1804, 3304 Existing Building 101.4.7, 102.6, 705.3, 912.2.2, 915.1, 11B- 202 Additions D103.1
Alteration D103.1 Change of occupancy D103.2 Flood-resistant 104.3.1, Appendix G Historic 101.4.7
Relocated structures D103.3
Repairs 101.4.7, 116.5 Rodentproofing Appendix F Exit (see Means of Egress) 1022, 1023, 1024, 1025, 1026, 1027 Atrium 404.10, 1023.2 Boiler room 1006.2.1.1 Configuration 1007 Construction 713.2, 1019, 1023.2 Doorways 1007 Dwellings 1006.2.2.6, 1006.3.4.1 Electrical rooms 1006.2.2.4
Enclosure 707.3.2, 1023.2 Fire resistance 707.3, 1019, 1023.2
Furnace rooms 1006.2.2.1
Group H-5 415.11.6.6 High rise 403.5, 403.6, 1025 Horizontal 707.3.5, 1026 Incinerator rooms 1006.2.2.1
CBC § 12.7 Medium relevance — show source text
** Braced wall panels shall have gypsum wall board installed on the side of the wall opposite the bracing material. Gypsum wall board shall be not less than [1] / 2 inch (12.7 mm) in thickness and be fastened with nails or screws in accordance with Table R602.3(1) for exterior sheathing or Table R702.3.5 for interior gypsum wall board. Spacing of fasteners at panel edges for gypsum wall board opposite Method LIB bracing shall not exceed 8 inches (203 mm). Interior finish material shall not be glued in Seismic Design Categories D 0, D 1 and D 2 . Exceptions:
- Interior finish material is not required opposite wall panels that are braced in accordance with Methods GB, BVWSP, ABW, PFH, PFG and CS-PF, unless otherwise required by Section R302.6.
- An approved interior finish material with an in-plane shear resistance equivalent to gypsum board shall be permitted to be substituted, unless otherwise required by Section R302.6.
- Except for Method LIB, gypsum wall board is permitted to be omitted provided that the required length of bracing in Tables R602.10.3(1) and R602.10.3(3) is multiplied by the appropriate adjustment factor in Tables R602.10.3(2) and R602.10.3(4), respectively, unless otherwise required by Section R302.6. R602.10.4.4 Panel joints. Vertical joints of panel sheathing shall occur over and be fastened to common studs. Horizontal joints of panel sheathing in braced wall panels shall occur over and be fastened to common blocking of a thickness of 1 [1] / 2 inches (38 mm) or greater.
Exceptions:
- For methods WSP and CS-WSP, blocking of horizontal joints is permitted to be omitted when adjustment factor No. 8 of Table R602.10.3(2) or No. 10 of Table R602.10.3(4) is applied.
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WALL CONSTRUCTION
- Vertical joints of panel sheathing shall be permitted to occur over double studs, where adjoining panel edges are attached to separate studs with the required panel edge fastening schedule, and the adjacent studs are attached together with two rows of 10d box nails [3 inches by 0.128 inch (76.2 mm by 3.25 mm)] at 10 inches o.c. (254 mm).
- Blocking at horizontal joints shall not be required in wall segments that are not counted as braced wall panels.
- Where Method GB panels are installed horizontally, blocking of horizontal joints is not required.
R602.10.5 Minimum length of a braced wall panel. The minimum length of a braced wall panel shall comply with Table R602.10.5. For Methods CS-WSP and CS-SFB, the minimum panel length shall be based on the adjacent clear opening height in accordance with Table R602.10.5 and Figure R602.10.5. Where a panel has an opening on either side of differing heights, the taller opening height shall be used to determine the panel length.
|TABLE R602.10.
CBC § 2304.9.2 Medium relevance — show source text
2304.9.2 Layup patterns. Lumber decking is permitted to be laid up following one of five standard patterns as defined in Sections 2304.9.2.1 through 2304.9.2.5.
2304.9.2.1 Simple span pattern. All pieces shall be supported on their ends (in other words, by two supports).
2304.9.2.2 Two-span continuous pattern. All pieces shall be supported by three supports, and all end joints shall occur in line on alternating supports. Supporting members shall be designed to accommodate the load redistribution caused by this pattern.
2304.9.2.3 Combination simple and two-span continuous pattern. Courses in end spans shall be alternating simple-span pattern and two-span continuous pattern. End joints shall be staggered in adjacent courses and shall bear on supports.
2304.9.2.4 Cantilevered pieces intermixed pattern. The decking shall extend across not fewer than three spans. Pieces in each starter course and every third course shall be simple span pattern. Pieces in other courses shall be cantilevered over the supports with end joints at alternating quarter or third points of the spans. Each piece shall bear on one support or more.
2304.9.2.5 Controlled random pattern. The decking shall extend across not fewer than three spans. End joints of pieces within 6 inches (152 mm) of the end joints of the adjacent pieces in either direction shall be separated by not fewer than two intervening courses. In the end bays, each piece shall bear on one support or more. Where an end joint occurs in an end bay, the next piece in the same course shall continue over the first inner support for not less than 24 inches (610 mm). The details of the controlled random pattern shall be as specified for each decking material in Section 2304.9.3.3, 2304.9.4.3 or 2304.9.5.3.
2025 CALIFORNIA BUILDING CODE 23-15
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WOOD
Decking that cantilevers beyond a support for a horizontal distance greater than 18 inches (457 mm), 24 inches (610 mm) or 36 inches (914 mm) for 2-inch (51 mm), 3-inch (76 mm) and 4-inch (102 mm) nominal thickness decking, respectively, shall comply with the following:
- The maximum cantilevered length shall be 30 percent of the length of the first adjacent interior span.
- A structural fascia shall be fastened to each decking piece to maintain a continuous, straight line.
- End joints shall not be in the decking between the cantilevered end of the decking and the centerline of the first adjacent interior span.
2304.9.3 Mechanically laminated decking. Mechanically laminated decking shall comply with Sections 2304.9.3.1 through 2304.9.3.3.
2304.9.3.1 General. Mechanically laminated decking consists of square-edged dimension lumber laminations set on edge and nailed to the adjacent pieces and to the supports.
2304.9.3.2 Nailing. The length of nails connecting laminations shall be not less than two and one-half times the net thickness of each lamination.
Frequently asked questions
Can I install panels in any orientation as long as I fasten them per the table?
No. The Code requires the panel strength axis to be either parallel or perpendicular to supports and certain span ratings require a specific orientation; check the table note that applies to your panel for required orientation.
What spacing do I use at panel edges vs the field?
Edge (panel perimeter) fastener spacing is normally tighter than the field: typical prescriptive schedules show 6" o.c. at edges and 12" o.c. in the field for many wood structural panels — but confirm the exact table entry for your panel/thickness/framing spacing in § 2304.10.
Do I need to change nailing near roof edges or in high wind areas?
Yes. The roof‑sheathing table notes require reduced spacing (for example, 4" o.c. near edges) and sometimes special ring‑shank nails in specified wind zones/exposures; follow the table notes in § 2304.8.
Are tongue‑and‑groove decking orientation and nailing special?
Yes. Tongue‑and‑groove decking must be installed with tongues up on sloped roofs and the Code prescribes both toe‑nailing and face‑nailing patterns and spike requirements depending on decking thickness. See §§ 2304.9.1 and 2304.9.4/9.5.
What if my panel/thickness/framing spacing is not in the tables?
If your exact combination is not tabulated, you must design sheathing/fastening according to the general design provisions of Chapter 23 (engineered design) rather than the prescriptive tables.
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- Means of Egress
- Accessibility
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- Roofing & Roof Assemblies
- Structural Design
- Special Inspections & Tests
- Foundations & Soils
- Concrete
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- Elevators & Conveying Systems
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