ADOPTS WITH AMENDMENTS:

International Building Code 2021 (IBC 2021)

Heads up: There are no amended sections in this chapter.

User notes:

About this chapter: Chapter 23 provides minimum requirements for the design of buildings and structures that use wood and wood-based products. The chapter is organized around three design methodologies: allowable stress design (ASD), load and resistance factor design (LRFD) and conventional light-frame construction. In addition it allows the use of the American Wood Council Wood Frame Construction Manual for a limited range of structures. Included in the chapter are references to design and manufacturing standards for various wood and wood-based products; general construction requirements; design criteria for lateral force-resisting systems and specific requirements for the application of the three design methods.

Code development reminder: Code change proposals to this chapter will be considered by the IBC—Structural Code Development Committee during the 2022 (Group B) Code Development Cycle.

The provisions of this chapter shall govern the materials, design, construction and quality of wood members and their fasteners.
For the purposes of this chapter, where dimensions of lumber are specified, they shall be deemed to be nominal dimensions unless specifically designated as actual dimensions (see Section 2304.2).

The design of structural elements or systems, constructed partially or wholly of wood or wood-based products, shall be in accordance with one of the following methods:

  1. Allowable stress design in accordance with Sections 2304, 2305 and 2306.
  2. Load and resistance factor design in accordance with Sections 2304, 2305 and 2307.
  3. Conventional light-frame construction in accordance with Sections 2304 and 2308.
  4. AWC WFCM in accordance with Section 2309.
  5. The design and construction of log structures in accordance with the provisions of ICC 400.
Structural sawn lumber; end-jointed lumber; prefabricated wood I-joists; structural glued-laminated timber; wood structural panels; fiberboard sheathing (where used structurally); hardboard siding (where used structurally); particleboard; preservative-treated wood; structural log members; structural composite lumber; round timber poles and piles; fire-retardant-treated wood; hardwood plywood; wood trusses; joist hangers; nails; and staples shall conform to the applicable provisions of this section.
Sawn lumber used for load-supporting purposes, including end-jointed or edge-glued lumber, machine stress-rated or machine-evaluated lumber, shall be identified by the grade mark of a lumber grading or inspection agency that has been approved by an accreditation body that complies with DOC PS 20 or equivalent. Grading practices and identification shall comply with rules published by an agency approved in accordance with the procedures of DOC PS 20 or equivalent procedures.
In lieu of a grade mark on the material, a certificate of inspection as to species and grade issued by a lumber grading or inspection agency meeting the requirements of this section is permitted to be accepted for precut, remanufactured or rough-sawn lumber and for sizes larger than 3 inches (76 mm) nominal thickness.
Approved end-jointed lumber is permitted to be used interchangeably with solid-sawn members of the same species and grade. End-jointed lumber used in an assembly required to have a fire-resistance rating shall have the designation "Heat Resistant Adhesive" or "HRA" included in its grade mark.
Structural capacities and design provisions for prefabricated wood I-joists shall be established and monitored in accordance with ASTM D5055.
Glued-laminated timbers shall be manufactured and identified as required in ANSI/APA 190.1 and ASTM D3737.
Cross-laminated timbers shall be manufactured and identified in accordance with ANSI/APA PRG 320.
Wood structural panels, where used structurally (including those used for siding, roof and wall sheathing, subflooring, diaphragms and built-up members), shall conform to the requirements for their type in DOC PS 1, DOC PS 2 or ANSI/APA PRP 210. Each panel or member shall be identified for grade, bond classification, and Performance Category by the trademarks of an approved testing and grading agency. The Performance Category value shall be used as the "nominal panel thickness" or "panel thickness" whenever referenced in this code. Wood structural panel components shall be designed and fabricated in accordance with the applicable standards listed in Section 2306.1 and identified by the trademarks of an approved testing and inspection agency indicating conformance to the applicable standard. In addition, wood structural panels where permanently exposed in outdoor applications shall be of exterior type, except that wood structural panel roof sheathing exposed to the outdoors on the underside is permitted to be Exposure 1 type.
Fiberboard for its various uses shall conform to ASTM C208. Fiberboard sheathing, where used structurally, shall be identified by an approved agency as conforming to ASTM C208.
To ensure tight-fitting assemblies, edges shall be manufactured with square, shiplapped, beveled, tongue-and-groove or U-shaped joints.
Where used as roof insulation in all types of construction, fiberboard shall be protected with an approved roof covering.
Where installed and fireblocked to comply with Chapter 7, fiberboards are permitted as wall insulation in all types of construction. In fire walls and fire barriers, unless treated to comply with Section 803.1 for Class A materials, the boards shall be cemented directly to the concrete, masonry or other noncombustible base and shall be protected with an approved noncombustible veneer anchored to the base without intervening airspaces.
Fiberboard wall insulation applied on the exterior of foundation walls shall be protected below ground level with a bituminous coating.
Hardboard siding shall conform to the requirements of ANSI A135.6 and, where used structurally, shall be identified by the label of an approved agency. Hardboard underlayment shall meet the strength requirements of 7/32-inch (5.6 mm) or 1/4-inch (6.4 mm) service class hardboard planed or sanded on one side to a uniform thickness of not less than 0.200 inch (5.1 mm). Prefinished hardboard paneling shall meet the requirements of ANSI A135.5. Other basic hardboard products shall meet the requirements of ANSI A135.4. Hardboard products shall be installed in accordance with manufacture's recommendations.
Particleboard shall conform to ANSI A208.1. Particleboard shall be identified by the grade mark or certificate of inspection issued by an approved agency. Particleboard shall not be utilized for applications other than indicated in this section unless the particleboard complies with the provisions of Section 2306.3.
Particleboard floor underlayment shall conform to Type PBU of ANSI A208.1. Type PBU underlayment shall be not less than 1/4-inch (6.4 mm) thick and shall be installed in accordance with the instructions of the Composite Panel Association.
Lumber, timber, plywood, piles and poles supporting permanent structures required by Section 2304.12 to be preservative treated shall conform to AWPA U1 and M4. Lumber and plywood used in permanent wood foundation systems shall conform to Chapter 18.

Wood required by Section 2304.12 to be preservative treated shall bear the quality mark of an inspection agency that maintains continuing supervision, testing and inspection over the quality of the preservative-treated wood. Inspection agencies for preservative-treated wood shall be listed by an accreditation body that complies with the requirements of the American Lumber Standards Treated Wood Program, or equivalent. The quality mark shall be on a stamp or label affixed to the preservative-treated wood, and shall include the following information:

  1. Identification of treating manufacturer.
  2. Type of preservative used.
  3. Minimum preservative retention (pcf).
  4. End use for which the product is treated.
  5. AWPA standard to which the product was treated.
  6. Identity of the accredited inspection agency.
Where preservative-treated wood is used in enclosed locations where drying in service cannot readily occur, such wood shall be at a moisture content of 19 percent or less before being covered with insulation, interior wall finish, floor covering or other materials.
Structural capacities for structural composite lumber shall be established and monitored in accordance with ASTM D5456.
Stress grading of structural log members of nonrectangular shape, as typically used in log buildings, shall be in accordance with ASTM D3957. Such structural log members shall be identified by the grade mark of an approved lumber grading or inspection agency. In lieu of a grade mark on the material, a certificate of inspection as to species and grade issued by a lumber grading or inspection agency meeting the requirements of this section shall be permitted.
Round timber poles and piles shall comply with ASTM D3200 and ASTM D25, respectively.
Engineered wood rim boards shall conform to ANSI/APA PRR 410 or shall be evaluated in accordance with ASTM D7672. Structural capacities shall be in accordance with ANSI/APA PRR 410 or established in accordance with ASTM D7672. Rim boards conforming to ANSI/APA PRR 410 shall be marked in accordance with that standard.
Fire-retardant-treated wood is any wood product that, when impregnated with chemicals by a pressure process or other means during manufacture, shall have, when tested in accordance with ASTM E84 or UL 723, a listed flame spread index of 25 or less.  Additionally, the ASTM E84 or UL 723 test shall be continued for a 20-minute period and the flame front shall not progress more than 101/2 feet (3200 mm) beyond the centerline of the burners at any time during the test.
For wood products impregnated with chemicals by a pressure process, the process shall be performed in closed vessels under pressures not less than 50 pounds per square inch gauge (psig) (345 kPa).
For wood products impregnated with chemicals by other means during manufacture, the treatment shall be an integral part of the manufacturing process of the wood product. The treatment shall provide permanent protection to all surfaces of the wood product. The use of paints, coating, stains or other surface treatments is not an approved method of protection as required in this section.
Wood structural panels shall be tested with a ripped or cut longitudinal gap of 1/8 inch (3.2 mm).

In addition to the labels required in Section 2303.1.1 for sawn lumber and Section 2303.1.5 for wood structural panels, each piece of fire-retardant-treated lumber and wood structural panels shall be labeled. The label shall contain the following items:

  1. The identification mark of an approved agency in accordance with Section 1703.5.
  2. Identification of the treating manufacturer.
  3. The name of the fire-retardant treatment.
  4. The species of wood treated.
  5. Flame spread and smoke-developed index.
  6. Method of drying after treatment.
  7. Conformance with appropriate standards in accordance with Sections 2303.2.5 through 2303.2.8.
  8. For fire-retardant-treated wood exposed to weather, damp or wet locations, include the words "No increase in the listed classification when subjected to the Standard Rain Test" (ASTM D2898).
Design values for untreated lumber and wood structural panels, as specified in Section 2303.1, shall be adjusted for fire-retardant-treated wood. Adjustments to design values shall be based on an approved method of investigation that takes into consideration the effects of the anticipated temperature and humidity to which the fire-retardant-treated wood will be subjected, the type of treatment and redrying procedures.
The effect of treatment and the method of redrying after treatment, and exposure to high temperatures and high humidities on the flexure properties of fire-retardant-treated softwood plywood shall be determined in accordance with ASTM D5516. The test data developed by ASTM D5516 shall be used to develop adjustment factors, maximum loads and spans, or both, for untreated plywood design values in accordance with ASTM D6305. Each manufacturer shall publish the allowable maximum loads and spans for service as floor and roof sheathing for its treatment.
For each species of wood that is treated, the effects of the treatment, the method of redrying after treatment and exposure to high temperatures and high humidities on the allowable design properties of fire-retardant-treated lumber shall be determined in accordance with ASTM D5664. The test data developed by ASTM D5664 shall be used to develop modification factors for use at or near room temperature and at elevated temperatures and humidity in accordance with ASTM D6841. Each manufacturer shall publish the modification factors for service at temperatures of not less than 80°F (27°C) and for roof framing. The roof framing modification factors shall take into consideration the climatological location.
Where fire-retardant-treated wood is exposed to weather, or damp or wet locations, it shall be identified as "Exterior" to indicate there is no increase in the listed flame spread index as defined in Section 2303.2 when subjected to ASTM D2898.
Interior fire-retardant-treated wood shall have moisture content of not over 28 percent when tested in accordance with ASTM D3201 procedures at 92-percent relative humidity. Interior fire-retardant-treated wood shall be tested in accordance with Section 2303.2.5.1 or 2303.2.5.2. Interior fire-retardant-treated wood designated as Type A shall be tested in accordance with the provisions of this section.
Fire-retardant-treated wood shall be dried to a moisture content of 19 percent or less for lumber and 15 percent or less for wood structural panels before use. For wood kiln-dried after treatment (KDAT), the kiln temperatures shall not exceed those used in kiln drying the lumber and plywood submitted for the tests described in Section 2303.2.5.1 for plywood and 2303.2.5.2 for lumber.
See Section 603.1 for limitations on the use of fire-retardant-treated wood in buildings of Type I or II construction.
Hardwood and decorative plywood shall be manufactured and identified as required in HPVA HP-1.
Wood trusses shall comply with Sections 2303.4.1 through 2303.4.7.
Wood trusses shall be designed in accordance with the provisions of this code and accepted engineering practice. Members are permitted to be joined by nails, glue, bolts, timber connectors, metal connector plates or other approved framing devices.

The written, graphic and pictorial depiction of each individual truss shall be provided to the building official for approval prior to installation. Truss design drawings shall be provided with the shipment of trusses delivered to the job site. Truss design drawings shall include, at a minimum, the following information:

  1. Slope or depth, span and spacing.
  2. Location of all joints and support locations.
  3. Number of plies if greater than one.
  4. Required bearing widths.
  5. Design loads as applicable, including:

    5.1.  Top chord live load.

    5.2.  Top chord dead load.

    5.3.  Bottom chord live load.

    5.4.  Bottom chord dead load.

    5.5.  Additional loads and locations.

    5.6.  Environmental design criteria and loads (such as wind, rain, snow, seismic).

  6. Other lateral loads, including drag strutloads.
  7. Adjustments to wood member and metal connector plate design value for conditions of use.
  8. Maximum reaction force and direction, including maximum uplift reaction forces where applicable.
  9. Joint connection type and description, such as size and thickness or gage, and the dimensioned location of each joint connector except where symmetrically located relative to the joint interface.
  10. Size, species and grade for each wood member.
  11. Truss-to-truss connections and truss field assembly requirements.
  12. Calculated span-to-deflection ratio and maximum vertical and horizontal deflection for live and total load as applicable.
  13. Maximum axial tension and compression forces in the truss members.
  14. Required permanent individual truss member restraint location and the method and details of restraint and diagonal bracing to be used in accordance with Section 2303.4.1.2.

Where the truss design drawings designate the need for permanent individual truss member restraint, it shall be accomplished by one of the following methods:

  1. PITMR and PITMDB installed using standard industry lateral restraint and diagonal bracing details in accordance with TPI 1, Section 2.3.3.1.1, accepted engineering practice, or Figures 2303.4.1.2(1), (3) and (5).
  2. Individual truss member reinforcement in place of the specified lateral restraints (i.e., buckling reinforcement such as T-reinforcement, L-reinforcement, proprietary reinforcement, etc.) such that the buckling of any individual truss member is resisted internally by the individual truss. The buckling reinforcement of individual truss members shall be installed as shown on the truss design drawing, on supplemental truss member buckling reinforcement details provided by the truss designer or in accordance with Figures 2303.4.1.2 (2) and (4).
  3. A project-specific PITMR and PITMDB design provided by any registered design professional.
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

FIGURE 2303.4.1.2 (1)

PITMR AND PITMDB FOR TRUSS WEB MEMBERS REQUIRING ONE ROW OF PITMR

For SI: 1 inch - 25.4 mm, 1 foot = 304.8 mm.

FIGURE 2303.4.1.2(2)

ALTERNATIVE INSTALLATION USING BUCKLING REINFORCEMENT FOR TRUSS WEB MEMBERS IN LIEU OF ONE ROW OF PITMR

For SI: 1 inch = 25.4 mm.

FIGURE 2303.4.1.2(3)

PITMR AND PITMDB FOR TRUSS WEB MEMBERS REQUIRING TWO ROWS OF PITMR

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

FIGURE 2303.4.1.2(4)

ALTERNATIVE INSTALLATION USING BUCKLING REINFORCEMENT FOR TRUSS WEB MEMBERS IN LIEU OF TWO ROWS OF PITMR

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

FIGURE 2303.4.1.2(5)

PITMR and PITMDB FOR FLAT PORTION OF TOP CHORD IN A PIGGYBACK ASSEMBLY

Trusses installed without a diaphragm on the top or bottom chord shall require a project specific PITMR and PITMDB design prepared by a registered design professional.

Exception: Group U occupancies.

The owner or the owner's authorized agent shall contract with any qualified registered design professional for the design of the temporary installation restraint and diagonal bracing and the PITMR and PITMDB for all trusses with clear spans 60 feet (18 288 mm) or greater.
The individual or organization responsible for the design of trusses.

Where required by the registered design professional, the building official or the statutes of the jurisdiction in which the project is to be constructed, each individual truss design drawing shall bear the seal and signature of the truss designer.

Exceptions:

  1. Where a cover sheet and truss index sheet are combined into a single sheet and attached to the set of truss design drawings, the single cover/truss index sheet is the only document required to be signed and sealed by the truss designer.
  2. Where a cover sheet and a truss index sheet are separately provided and attached to the set of truss design drawings, the cover sheet and the truss index sheet are the only documents required to be signed and sealed by the truss designer.
The truss manufacturer shall provide a truss placement diagram that identifies the proposed location for each individually designated truss and references the corresponding truss design drawing. The truss placement diagram shall be provided as part of the truss submittal package, and with the shipment of trusses delivered to the job site. Truss placement diagrams that serve only as a guide for installation and do not deviate from the permit submittal drawings shall not be required to bear the seal or signature of the truss designer.
The truss submittal package provided by the truss manufacturer shall consist of each individual truss design drawing, the truss placement diagram, the permanent individual truss member restraint/bracing method and details and any other structural details germane to the trusses; and, as applicable, the cover/truss index sheet.
The design for the transfer of loads and anchorage of each truss to the supporting structure is the responsibility of the registered design professional.
Truss members and components shall not be cut, notched, drilled, spliced or otherwise altered in any way without written concurrence and approval of a registered design professional. Alterations resulting in the addition of loads to any member (for example, HVAC equipment, piping, additional roofing or insulation) shall not be permitted without verification that the truss is capable of supporting such additional loading.
In addition to Sections 2303.4.1 through 2303.4.5, the design, manufacture and quality assurance of metal-plate-connected wood trusses shall be in accordance with TPI 1. Job-site inspections shall be in compliance with Section 110.4, as applicable.
Trusses not part of a manufacturing process in accordance with either Section 2303.4.6 or a referenced standard, which provides requirements for quality control done under the supervision of a third-party quality control agency, shall be manufactured in compliance with Sections 1704.2.5 and 1705.5, as applicable.
Joist hangers shall be in accordance with ASTM D7147.
Nails and staples shall conform to requirements of ASTM F1667, including Supplement 1. Nails used for framing and sheathing connections shall have minimum average bending yield strengths as follows: 80 kips per square inch (ksi) (551 MPa) for shank diameters larger than 0.177 inch (4.50 mm) but not larger than 0.254 inch (6.45 mm), 90 ksi (620 MPa) for shank diameters larger than 0.142 inch (3.61 mm) but not larger than 0.177 inch (4.50 mm) and 100 ksi (689 MPa) for shank diameters of not less than 0.099 inch (2.51 mm) but not larger than 0.142 inch (3.61 mm). Staples used for framing and sheathing connections shall have minimum average bending moments as follows: 3.6 in.-lbs (0.41 N-m) for No. 16 gage staples, 4.0 in.-lbs (0.45 N-m) for No. 15 gage staples, and 4.3 in.-lbs (0.49 N-m) for No. 14 gage staples.
Consideration shall be given in design for the effects of wood cross-grain dimensional changes that occur as a result of changes in the wood moisture content after installation.
The provisions of this section apply to design methods specified in Section 2302.1.
Computations to determine the required sizes of members shall be based on the net dimensions (actual sizes) and not nominal sizes.
The framing of exterior and interior walls shall be in accordance with the provisions specified in Section 2308 unless a specific design is furnished.
Studs shall have full bearing on a 2-inch-thick (actual 11/2-inch, 38 mm) or larger plate or sill having a width not less than equal to the width of the studs.
Headers, double joists, trusses or other approved assemblies that are of adequate size to transfer loads to the vertical members shall be provided over window and door openings in load-bearing walls and partitions.
Wood walls and bearing partitions shall not support more than two floors and a roof unless an analysis satisfactory to the building official shows that shrinkage of the wood framing will not have adverse effects on the structure or any plumbing, electrical or mechanical systems or other equipment installed therein due to excessive shrinkage or differential movements caused by shrinkage. The analysis shall show that the roof drainage system and the foregoing systems or equipment will not be adversely affected or, as an alternate, such systems shall be designed to accommodate the differential shrinkage or movements.
The framing of wood-joisted floors and wood-framed roofs shall be in accordance with the provisions specified in Section 2308 unless a specific design is furnished.
Combustible framing shall be not less than 2 inches (51 mm), but shall be not less than the distance specified in Sections 2111 and 2113 and the International Mechanical Code, from flues, chimneys and fireplaces, and 6 inches (152 mm) away from flue openings.
Wall sheathing on the outside of exterior walls, including gables, and the connection of the sheathing to framing shall be designed in accordance with the general provisions of this code and shall be capable of resisting wind pressures in accordance with Section 1609.
Where wood structural panel sheathing is used as the exposed finish on the outside of exterior walls, it shall have an exterior exposure durability classification. Where wood structural panel sheathing is used elsewhere, but not as the exposed finish, it shall be of a type manufactured with exterior glue (Exposure 1 or Exterior). Wood structural panel sheathing, connections and framing spacing shall be in accordance with Table 2304.6.1 for the applicable wind speed and exposure category where used in enclosed buildings with a mean roof height not greater than 30 feet (9144 mm) and a topographic factor (Kz t) of 1.0.

TABLE 2304.6.1

MAXIMUM ALLOWABLE STRESS DESIGN WIND SPEED, Vasd PERMITTED FOR WOOD STRUCTURAL PANEL WALL SHEATHING USED TO RESIST WIND PRESSURESa, b, c

MINIMUM NAIL MINIMUM WOOD STRUCTURAL PANEL SPAN RATING MINIMUM NOMINAL PANEL THICKNESS (inches) MAXIMUM WALL STUD SPACING (inches) PANEL NAIL SPACING MAXIMUM ALLOWABLE STRESS DESIGN WIND SPEED, Vasd d (MPH)
Size Penetration (inches) Edges (inches o.c.) Field (inches o.c.) Wind exposure category
B C D
6d common (2.0" × 0.113") 1.5 24/0 3/8 16 6 12 110 90 85
24/16 7/16 16 6 12 110 100 90
6 150 125 110
8d common (2.5" × 0.131") 1.75 24/16 7/16 16 6 12 130 110 105
6 150 125 110
24 6 12 110 90 85
6 110 90 85

For SI: 1 inch = 25.4 mm, 1 mile per hour = 0.447 m/s.

  1. 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.
  2. The table is based on wind pressures acting toward and away from building surfaces in accordance with Section 30.7 of ASCE 7. Lateral requirements shall be in accordance with Section 2305 or 2308.
  3. 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.
  4. Vasd shall be determined in accordance with Section 1609.3.1.
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.
Structural floor sheathing and structural roof sheathing shall comply with Sections 2304.8.1 and 2304.8.2, respectively.

TABLE 2304.8(1)

ALLOWABLE SPANS FOR LUMBER FLOOR AND ROOF SHEATHING

SPAN (inches) MINIMUM NET THICKNESS (inches) OF LUMBER PLACED
Perpendicular to supports Diagonally to supports
Surfaced drya Surfaced unseasoned Surfaced drya Surfaced unseasoned
Floors
24 3/4 25/32 3/4 25/32
16 5/8 11/16 5/8 11/16
Roofs
24 5/8 11/16 3/4 25/32

For SI: 1 inch = 25.4 mm.

  1. Maximum 19-percent moisture content.

TABLE 2304.8(2)

SHEATHING LUMBER, MINIMUM GRADE REQUIREMENTS: BOARD GRADE

SOLID FLOOR OR ROOF SHEATHING SPACED ROOF SHEATHING GRADING RULES
Utility Standard NLGA, WCLIB, WWPA
4 common or utility 3 common or standard NLGA, WCLIB, WWPA, NSLB or NELMA
No. 3 No. 2 SPIB
Merchantable Construction common RIS

 

TABLE 2304.8(3)

ALLOWABLE SPANS AND LOADS FOR WOOD STRUCTURAL PANEL SHEATHING AND SINGLE-FLOOR GRADES CONTINUOUS OVER TWO OR MORE SPANS WITH STRENGTH AXIS PERPENDICULAR TO SUPPORTSa

SHEATHING GRADES ROOFb FLOORc
Panel span rating roof/floor span Panel thickness (inches) Maximum span (inches) Loadd (psf) Maximum span (inches)
With edge supporte Without edge support Total load Live load
16/0 3/8 16 16 40 30 0
20/0 3/8 20 20 40 30 0
24/0 3/8, 7/16, 1/2 24 20f 40 30 0
24/16 7/16, 1/2 24 24 50 40 16
32/16 15/32, 1/2, 5/8 32 28 40 30 16g
40/20 19/32, 5/8, 3/4, 7/8 40 32 40 30 20g,h
48/24 23/32, 3/4, 7/8 48 36 45 35 24
54/32 7/8, 1 54 40 45 35 32
60/32 7/8, 11/8 60 48 45 35 32
SINGLE FLOOR GRADES ROOFb FLOORc
Panel span rating Panel thickness (inches) Maximum span (inches) Loade (psf) Maximum span (inches)
With edge supporte Without edge support Total load Live load
16 o.c. 1/2, 19/32, 5/8 24 24 50 40 16g
20 o.c. 19/32, 5/8, 3/4 32 32 40 30 20g,h
24 o.c. 23/32, 3/4 48 36 35 25 24
32 o.c. 7/8, 1 48 40 50 40 32
48 o.c. 13/32, 11/8 60 48 50 40 48

For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kN/m2.

  1. Applies to panels 24 inches or wider.
  2. Uniform load deflection limitations 1/180 of span under live load plus dead load, 1/240 under live load only.
  3. Panel edges shall have approved tongue-and-groove joints or shall be supported with blocking unless 1/4-inch minimum thickness underlayment or 11/2 inches of approved cellular or lightweight concrete is placed over the subfloor, or finish floor is 3/4-inch wood strip. Allowable uniform load based on deflection of 1/360 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.
  4. Allowable load at maximum span.
  5. 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.
  6. For 1/2-inch panel, maximum span shall be 24 inches.
  7. Span is permitted to be 24 inches on center where 3/4-inch wood strip flooring is installed at right angles to joist.
  8. 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 2304.8(4)

ALLOWABLE SPAN FOR WOOD STRUCTURAL PANEL COMBINATION SUBFLOOR-UNDERLAYMENT (SINGLE FLOOR)a(Panels Continuous Over Two or More Spans and Strength Axis Perpendicular to Supports)

IDENTIFICATION MAXIMUM SPACING OF JOISTS (inches)
16 20 24 32 48
Species groupb Thickness (inches)
1 1/2 5/8 3/4
2, 3 5/8 3/4 7/8
4 3/4 7/8 1
Single floor span ratingc 16 o.c. 20 o.c. 24 o.c. 32 o.c. 48 o.c.

For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kN/m2.

  1. Spans limited to value shown because of possible effects of concentrated loads. Allowable uniform loads based on deflection of 1/360 of span is 100 pounds per square foot except allowable total uniform load for 11/8-inch wood structural panels over joists spaced 48 inches on center is 65 pounds per square foot. Panel edges shall have approved tongue-and-groove joints or shall be supported with blocking, unless 1/4-inch minimum thickness underlayment or 11/2 inches of approved cellular or lightweight concrete is placed over the subfloor, or finish floor is 3/4-inch wood strip.
  2. Applicable to all grades of sanded exterior-type plywood. See DOC PS 1 for plywood species groups.
  3. Applicable to Underlayment grade, C-C (Plugged) plywood, and Single Floor grade wood structural panels.

TABLE 2304.8(5)

ALLOWABLE LOAD (PSF) FOR WOOD STRUCTURAL PANEL ROOF SHEATHING CONTINUOUS OVER TWO OR MORE SPANS AND STRENGTH AXIS PARALLEL TO SUPPORTS (Plywood structural panels are five-ply, five-layer unless otherwise noted)a

PANEL GRADE THICKNESS (inch) MAXIMUM SPAN (inches) LOAD AT MAXIMUM SPAN (psf)
Live Total
Structural I sheathing 7/16 24 20 30
15/32 24 35b 45b
1/2 24 40b 50b
19/32, 5/8 24 70 80
23/32, 3/4 24 90 100
Sheathing, other grades covered in DOC PS 1 or DOC PS 2 7/16 16 40 50
15/32 24 20 25
1/2 24 25 30
19/32 24 40b 50b
5/8 24 45b 55b
23/32, 3/4 24 60b 65b

For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kN/m2.

  1. Uniform load deflection limitations 1/180 of span under live load plus dead load, 1/240 under live load only. Edges shall be blocked with lumber or other approved type of edge supports.
  2. For composite and four-ply plywood structural panel, load shall be reduced by 15 pounds per square foot.

Structural floor sheathing shall be designed in accordance with the general provisions of this code.

Floor sheathing conforming to the provisions of Table 2304.8(1), 2304.8(2), 2304.8(3) or 2304.8(4) shall be deemed to meet the requirements of this section.

Structural roof sheathing shall be designed in accordance with the general provisions of this code and the special provisions in this section.

Roof sheathing conforming to the provisions of Table 2304.8(1), 2304.8(2), 2304.8(3) or 2304.8(5) shall be deemed to meet the requirements of this section. Wood structural panel roof sheathing shall be of a type manufactured with exterior glue (Exposure 1 or Exterior).

Lumber decking shall be designed and installed in accordance with the general provisions of this code and Sections 2304.9.1 through 2304.9.5.3. Other lumber decking patterns and connection designs shall be substantiated through engineering analysis.
Each piece of lumber decking shall be square-end trimmed. Where random lengths are furnished, each piece shall be square end trimmed across the face so that not less than 90 percent of the pieces are within 0.5 degrees (0.00873 rad) of square. The ends of the pieces shall be permitted to be beveled up to 2 degrees (0.0349 rad) from the vertical with the exposed face of the piece slightly longer than the opposite face of the piece. Tongue-and-groove decking shall be installed with the tongues up on sloped or pitched roofs with pattern faces down.
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.
All pieces shall be supported on their ends (in other words, by two supports).
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.
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.
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.

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.

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:

  1. The maximum cantilevered length shall be 30 percent of the length of the first adjacent interior span.
  2. A structural fascia shall be fastened to each decking piece to maintain a continuous, straight line.
  3. End joints shall not be in the decking between the cantilevered end of the decking and the centerline of the first adjacent interior span.
Mechanically laminated decking shall comply with Sections 2304.9.3.1 through 2304.9.3.3.
Mechanically laminated decking consists of square-edged dimension lumber laminations set on edge and nailed to the adjacent pieces and to the supports.

The length of nails connecting laminations shall be not less than two and one-half times the net thickness of each lamination. Where decking supports are 48 inches (1219 mm) on center or less, side nails shall be installed not more than 30 inches (762 mm) on center alternating between top and bottom edges, and staggered one-third of the spacing in adjacent laminations. Where supports are spaced more than 48 inches (1219 mm) on center, side nails shall be installed not more than 18 inches (457 mm) on center alternating between top and bottom edges and staggered one-third of the spacing in adjacent laminations. For mechanically laminated decking constructed with laminations of 2-inch (51 mm) nominal thickness, nailing in accordance with Table 2304.9.3.2 shall be permitted. Two side nails shall be installed at each end of butt-jointed pieces.

Laminations shall be toenailed to supports with 20d or larger common nails. Where the supports are 48 inches (1219 mm) on center or less, alternate laminations shall be toenailed to alternate supports; where supports are spaced more than 48 inches (1219 mm) on center, alternate laminations shall be toenailed to every support. For mechanically laminated decking constructed with laminations of 2-inch (51 mm) nominal thickness, toenailing in accordance with Table 2304.9.3.2 shall be permitted.


TABLE 2304.9.3.2

FASTENING SCHEDULE FOR MECHANICALLY LAMINATED DECKING USING LAMINATIONS OF 2-INCH NOMINAL THICKNESS

MINIMUM NAIL SIZE (Length x Diameter) (inches) MAXIMUM SPACING BETWEEN FACE NAILS a, b (inches) NUMBER OF TOENAILS INTO SUPPORTSc
Decking Supports ≤ 48 inches o.c. Decking Supports > 48 inches o.c.
4 × 0.192 30 18 1
4 × 0.162 24 14 2
4 × 0.148 22 13 2
31/2 × 0.162 20 12 2
31/2 × 0.148 19 11 2
31/2 × 0.135 17 10 2
3 × 0.148 11 7 2
3 × 0.128 9 5 2
23/4 × 0.148 10 6 2
23/4 × 0.131 9 6 3
23/4 × 0.120 8 5 3

For SI: 1 inch = 25.4 mm

  1. Nails shall be driven perpendicular to the lamination face, alternating between top and bottom edges.
  2. 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 staggered one-half of the spacing in adjacent laminations.
  3. 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.
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.
Two-inch (51 mm) sawn tongue-and-groove decking shall comply with Sections 2304.9.4.1 through 2304.9.4.3.
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.
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.
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.
Three- and four-inch (76 mm and 102 mm) sawn tongue-and-groove decking shall comply with Sections 2304.9.5.1 through 2304.9.5.3.
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.
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.
There shall be a minimum distance of 48 inches (1219 mm) between end joints in adjacent courses. Pieces not bearing on a support are permitted to be located in interior bays provided that the adjacent pieces in the same course continue over the support for not less than 24 inches (610 mm). This condition shall not occur more than once in every six courses in each interior bay.
Connectors and fasteners shall comply with the applicable provisions of Sections 2304.10.1 through 2304.10.8 .
Fire-resistance ratings for connections in Type IV-A, IV-B or IV-C construction shall be determined by one of the following:
  1. Testing in accordance with Section 703.2 where the connection is part of the fire-resistance test.
  2. Engineering analysis that demonstrates that the temperature rise at any portion of the connection is limited to an average temperature rise of 250°F (139°C), and a maximum temperature rise of 325°F (181°C), for a time corresponding to the required fire-resistance rating of the structural element being connected. For the purposes of this analysis, the connection includes connectors, fasteners and portions of wood members included in the structural design of the connection.
Connections for wood members shall be designed in accordance with the appropriate methodology in Section 2302.1. The number and size of fasteners connecting wood members shall be not less than that set forth in Table 2304.10.2.

TABLE 2304.10.2

FASTENING SCHEDULE

DESCRIPTION OF BUILDING ELEMENTS NUMBER AND TYPE OF FASTENERg SPACING AND LOCATION
Roof

1. Blocking between ceiling joists, rafters or trusses to top plate or other framing below

4-8d box (21/2" x 0.113"); or

3-8d common (21/2" × 0.131"); or

3-10d box (3" × 0.128"); or

3-3" × 0.131" nails; or 3-3"14 gage staples, 7/16" crown
Each end, toenail

Blocking between rafters or truss not at the wall top plate, to rafter or truss

2-8d common (21/2" × 0.131")

2-3" × 0.131" nails

2-3" 14 gage staples
Each end, toenail
2-16 d common (31/2" × 0.162")

3-3" × 0.131" nails

3-3" 14 gage staples
End nail

Flat blocking to truss and web filler

16d common (31/2" × 0.162") @ 6" o.c.

3" × 0.131" nails @ 6" o.c.

3" × 14 gage staples @ 6" o.c
Face nail
2. Ceiling joists to top plate 4-8d box (21/2" x 0.113"); or

3-8d common (21/2" × 0.131"); or

3-10d box (3" × 0.128"); or

3-3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown
Each joist, toenail
3. Ceiling joist not attached to parallel rafter, laps over partitions (no thrust) (see Section 2308.7.3.1, Table 2308.7.3.1) 3-16d common (31/2" × 0.162"); or

4-10d box (3" × 0.128"); or

4-3" × 0.131" nails; or

4-3" 14 gage staples, 7/16" crown
Face nail
4. Ceiling joist attached to parallel rafter (heel joint) (see Section 2308.7.3.1, Table 2308.7.3.1) Per Table 2308.7.3.1 Face nail
5. Collar tie to rafter 3-10d common (3" × 0.148"); or

4-10d box (3" × 0.128"); or

4-3" × 0.131" nails; or

4-3" 14 gage staples, 7/16" crown
Face nail
6. Rafter or roof truss to top plate (See Section 2308.7.5, Table 2308.7.5) 3-10 common (3" × 0.148"); or

3-16d box (31/2" × 0.135"); or

4-10d box (3" × 0.128"); or

4-3" × 0.131 nails; or

4-3" 14 gage staples, 7/16" crown
2 toenails on one side and 1 toenail on opposite side of rafter or trussc
7. Roof rafters to ridge valley or hip rafters; or roof rafter to 2-inch ridge beam 2-16d common (31/2" × 0.162"); or

3-16d box (31/2" × 0.135"); or

3-10d box (3" × 0.128"); or

3-3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown
End nail
3-10d common (31/2" × 0.148"); or

4-16d box (31/2" × 0.135"); or

4-10d box (3" × 0.128"); or

4-3" × 0.131" nails; or

4-3" 14 gage staples, 7/16" crown
Toenail
Wall
8. Stud to stud (not at braced wall panels) 16d common (31/2" × 0.162"); 24" o.c. face nail
10d box (3" × 0.128"); or

3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown
16" o.c. face nail
9. Stud to stud and abutting studs at intersecting wall corners (at braced wall panels) 16d common (31/2" × 0.162") 16" o.c. face nail
16d box (31/2" × 0.135"); or

3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown



12" o.c. face nail

10. Built-up header (2" to 2" header) 16d common (31/2" × 0.162") 16" o.c. each edge, face nail
16d box (31/2" × 0.135") 12" o.c. each edge, face nail
11. Continuous header to stud 4-8d common (21/2" × 0.131"); or

4-10d box (3" × 0.128"); or

5-8d box (21/2" x 0.113")
Toenail
12. Top plate to top plate 16d common (31/2" × 0.162") 16" o.c. face nail
10d box (3" × 0.128"); or

3" × 0.131" nails; or

3" 14 gage staples, 7/16" crown
12" o.c. face nail
13. Top plate to top plate, at end joints 8-16d common (31/2" × 0.162"); or

12-16d box (31/2" x 0.135"); or

12-10d box (3" × 0.128"); or

12-3" × 0.131" nails; or

12-3" 14 gage staples, 7/16" crown
Each side of end joint, face nail (minimum 24" lap splice length each side of end joint)
14. Bottom plate to joist, rim joist, band joist or blocking (not at braced wall panels) 16d common (31/2" × 0.162") 16" o.c. face nail
16d box (31/2" × 0.135"); or

3" × 0.131" nails; or

3" 14 gage staples, 7/16" crown
12" o.c. face nail
15. Bottom plate to joist, rim joist, band joist or blocking at braced wall panels 2-16d common (31/2" × 0.162"); or

3-16d box (31/2" × 0.135"); or

4-3" × 0.131" nails; or

4-3" 14 gage staples, 7/16" crown
16" o.c. face nail
16. Stud to top or bottom plate 3-16d box (31/2" x 0.135"); or

4-8d common (21/2" × 0.131"); or

4-10d box (3" × 0.128"); or

4-3" × 0.131" nails; or

4-8d box (21/2" x 0.113"); or

4-3" 14 gage staples, 7/16" crown
Toenail
2-16d common (31/2" × 0.162"); or

3-16d box (31/2" x 0.135"); or

3-10d box (3" × 0.128"); or

3-3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown
End nail
17. Top plates, laps at corners and intersections 2-16d common (31/2" × 0.162"); or

3-10d box (3" × 0.128"); or

3-3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown
Face nail
18. 1" brace to each stud and plate 3-8d box (21/2" x 0.113"); or

2-8d common (21/2" × 0.131"); or

2-10d box (3" × 0.128"); or

2-3" × 0.131" nails; or

2-3" 14 gage staples, 7/16" crown
Face nail
19. 1" × 6" sheathing to each bearing 3-8d box (21/2" x 0.113"); or

2-8d common (21/2" × 0.131"); or

2-10d box (3" × 0.128"); or

2-13/4" 16 gage staples, 1" crown
Face nail
20. 1" × 8" and wider sheathing to each bearing 3-8d common (21/2" × 0.131"); or

3-8d box (21/2" x 0.113"); or

3-10d box (3" × 0.128"); or

3-13/4" 16 gage staples, 1" crown
Face nail
Wider than 1" × 8"

3-8d common (21/2" x 0.131"); or

4-8d box (21/2" × 0.113"); or

3-10d box (3" × 0.128"); or

4-13/4" 16 gage staples, 1" crown
Floor
21. Joist to sill, top plate, or girder 4-8d box (21/2" × 0.113"); or

3-8d common (21/2" × 0.131"); or floor

3-10d box (3" × 0.128"); or

3-3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown
Toenail
22. Rim joist, band joist, or blocking to top plate, sill or other framing below 8d box (21/2" × 0.113") 4" o.c., toenail
8d common (21/2" × 0.131"); or

10d box (3" × 0.128"); or

3" × 0.131" nails; or

3" 14 gage staples, 7/16" crown
6" o.c., toenail
23. 1" × 6" subfloor or less to each joist 3-8d box (21/2" × 0.113"); or

2-8d common (21/2" × 0.131"); or

3-10d box (3" × 0.128"); or

2-13/4" 16 gage staples, 1" crown
Face nail
24. 2 subfloor to joist or girder 3-16d box (31/2" × 0.135"); or

2-16d common (31/2" × 0.162")
Blind and face nail
25. 2" planks (plank & beam — floor & roof) 3-16d box (31/2" × 0.135"); or

2-16d common (31/2" × 0.162")
Each bearing, face nail
26. Built-up girders and beams, 2" lumber layers 20d common (4" × 0.192") 32" o.c., face nail at top and bottom staggered on opposite sides
10d box (3" × 0.128"); or

3" × 0.131" nails; or

3" 14 gage staples, 7/16" crown
24" o.c. face nail at top and bottom staggered on opposite sides
And:

2-20d common (4" × 0.192"); or

3-10d box (3" × 0.128"); or

3-3" × 0.131" nails; or

3-3" 14 gage staples, 7/16" crown
Ends and at each splice, face nail
27. Ledger strip supporting joists or rafters 3-16d common (31/2" × 0.162"); or

4-16d box (31/2" × 0.135"); or

4-10d box (3" × 0.128"); or

4-3" × 0.131" nails; or

4-3" 14 gage staples, 7/16" crown
Each joist or rafter, face nail
28. Joist to band joist or rim joist 3-16d common (31/2" × 0.162"); or

4-10d box (3" × 0.128"); or

4-3" × 0.131" nails; or

4-3" 14 gage staples, 7/16" crown
End nail
29. Bridging or blocking to joist, rafter or truss 2-8d common (21/2" × 0.131"); or

2-10d box (3" × 0.128"); or

2-3" × 0.131" nails; or

2-3" 14 gage staples, 7/16" crown
Each end, toenail
Wood structural panels (WSP), subfloor, roof and interior wall sheathing to framing and particleboard wall sheathing to framinga
  Edges (inches) Intermediate supports (inches)
30. 3/8" — 1/2" 6d common or deformed (2" × 0.113"); or

23/8" × 0.113" nail (subfloor and wall)
6 12
8d common or deformed (21/2" × 0.131"× 0.281" head) (roof) or

RSRS-01 (23/8" × 0.113") nail (roof)d

6e

6e

13/4" 16 gage staple, 7/16" crown (subfloor and wall) 4 8
23/8" × 0.113"× 0.266" head nail (roof) 3f 3f
13/4" 16 gage staple, 7/16" crown (roof) 3f 3f

31. 19/32" — 3/4"

8d common (21/2" × 0.131"); or

deformed (2" × 0.113") (subfloor and wall)
6 12
8d common or deformed (21/2" × 0.131" × 0.281" head) (roof) or RSRS-01 (23/8" × 0.113") nail (roof)d 6e 6e
23/8" × 0.113"× 0.266" head nail; or

2" 16 gage staple, 7/16" crown
4 8

32. 7/8" — 11/4"

10d common (3" × 0.148"); or

deformed (21/2" × 0.131" × 0.281" head)
6 12
Other exterior wall sheathing

33. 1/2" fiberboard sheathingb

11/2" × 0.120", galvanized roofing nail (7/16" head diameter); or

11/4" 16 gage staple with 7/16" or 1" crown
3 6

34. 25/32" fiberboard sheathingb

13/4" × 0.120" galvanized roofing nail (7/16" diameter head); or

11/2" 16 gage staple with 7/16" or 1" crown
3 6
Wood structural panels, combination subfloor underlayment to framing

35. 3/4" and less

8d common (21/2" × 0.131"); or

deformed (2" × 0.113"); or

deformed (2" × 0.120")
6 12

36. 7/8" — 1"

8d common (21/2" × 0.131"); or

deformed (21/2" × 0.131"); or

deformed (21/2" × 0.120")
6 12

37. 11/8" — 11/4"

10d common (3" × 0.148"); or

deformed (21/2" × 0.131"); or

deformed (21/2" × 0.120")
6 12
Panel siding to framing

38. 1/2" or less

6d corrosion-resistant siding (17/8" × 0.106"); or

6d corrosion-resistant casing (2" × 0.099")
6 12

39. 5/8"

8d corrosion-resistant siding (23/8" × 0.128"); or

8d corrosion-resistant casing (21/2" × 0.113")
6 12
Wood structural panels (WSP), subfloor, roof and interior wall sheathing to framing and particleboard wall sheathing to framinga
    Edges (inches) Intermediate supports (inches)
Interior paneling
40. 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.

  1. 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.
  2. 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).
  3. 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.
  4. RSRS-01 is a Roof Sheathing Ring Shank nail meeting the specifications in ASTM F1667.
  5. Tabulated fastener requirements apply where the ultimate design wind speed 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 ultimate design wind speed is greater than 130 mph in Exposure 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.
  6. Fastening is only permitted where the ultimate design wind speed is less than or equal to 110 mph.
  7. 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 104.11.
Sheathing nails or other approved sheathing connectors shall be driven so that their head or crown is flush with the surface of the sheathing.
Connections depending on joist hangers or framing anchors, ties and other mechanical fastenings not otherwise covered are permitted where approved. The vertical load-bearing capacity, torsional moment capacity and deflection characteristics of joist hangers shall be determined in accordance with ASTM D7147.
Clips, staples, glues and other approved methods of fastening are permitted where approved.
Fasteners, including nuts and washers, and connectors in contact with preservative-treated and fire-retardant-treated wood shall be in accordance with Sections 2304.10.6.1 through 2304.10.6.4. The coating weights for zinc-coated fasteners shall be in accordance with ASTM A153. Stainless steel driven fasteners shall be in accordance with the material requirements of ASTM F1667.

Fasteners, including nuts and washers, in contact with preservative-treated wood shall be of hot-dipped zinc-coated galvanized steel, stainless steel, silicon bronze or copper. Staples shall be of stainless steel. Fasteners other than nails, staples, timber rivets, wood screws and lag screws shall be permitted to be of mechanically deposited zinc-coated steel with coating weights in accordance with ASTM B695, Class 55 minimum. Connectors that are used in exterior applications and in contact with preservative-treated wood shall have coating types and weights in accordance with the treated wood or connector manufacturer's recommendations. In the absence of manufacturer's recommendations, not less than ASTM A653, Type G185 zinc-coated galvanized steel, or equivalent, shall be used.

Exception: Plain carbon steel fasteners, including nuts and washers, in SBX/DOT and zinc borate preservative-treated wood in an interior, dry environment shall be permitted.

Fastenings, including nuts and washers, for wood foundations shall be as required in AWC PWF.
Fasteners, including nuts and washers, for fire-retardant-treated wood used in exterior applications or wet or damp locations shall be of hot-dipped zinc-coated galvanized steel, stainless steel, silicon bronze or copper. Staples shall be of stainless steel. Fasteners other than nails, staples, timber rivets, wood screws and lag screws shall be permitted to be of mechanically deposited zinc-coated steel with coating weights in accordance with ASTM B695, Class 55 minimum.
Fasteners, including nuts and washers, for fire-retardant-treated wood used in interior locations shall be in accordance with the manufacturer's recommendations. In the absence of manufacturer's recommendations, Section 2304.10.6.3 shall apply.
Where wall framing members are not continuous from the foundation sill to the roof, the members shall be secured to ensure a continuous load path. Where required, sheet metal clamps, ties or clips shall be formed of galvanized steel or other approved corrosion-resistant material not less than 0.0329-inch (0.836 mm) base metal thickness.
Wood columns and posts shall be framed to provide full end bearing. Alternatively, column-and-post end connections shall be designed to resist the full compressive loads, neglecting end-bearing capacity. Column-and-post end connections shall be fastened to resist lateral and net induced uplift forces.
Where a structure, portion thereof or individual structural elements are required by provisions of this code to be of heavy timber, the building elements therein shall comply with the applicable provisions of Sections 2304.11.1 through 2304.11.4. Minimum dimensions of heavy timber shall comply with the applicable requirements in Table 2304.11 based on roofs or floors supported and the configuration of each structural element, or in Sections 2304.11.2 through 2304.11.4. Lumber decking shall be in accordance with Section 2304.9.

TABLE 2304.11

MINIMUM DIMENSIONS OF HEAVY TIMBER STRUCTURAL MEMBERS

    MINIMUM NOMINAL SOLID SAWN SIZE MINIMUM GLUED- LAMINATED NET SIZE MINIMUM STRUCTURAL COMPOSITE LUMBER NET SIZE
SUPPORTING HEAVY TIMBER STRUCTURAL ELEMENTS Width, inch Depth, inch Width, inch Depth, inch Width, inch Depth, inch

Floor loads only or combined floor and roof loads

Columns;Framed sawn or glued-laminated timber arches that spring from the floor line; Framed timber trusses

8 8 63/4 81/4 7 71/2

Wood beams and girders

6 10 5 101/2 51/4 91/2

Roof loads only

Columns (roof and ceiling loads); Lower half of: wood-frame or glued-laminated arches that spring from the floor line or from grade

6 8 5 81/4 51/4 71/2

Upper half of: wood-frame or glued-laminated arches that spring from the floor line or from grade

6 6 5 6 51/4 51/2

Framed timber trusses and other roof framing;a Framed or glued-laminated arches that spring from the top of walls or wall abutments

4b 6 3b 67/8 31/2b 51/2

For SI: 1 inch = 25.4 mm.

  1. Spaced members shall be permitted to be composed of two or more pieces not less than 3 inches nominal in thickness where blocked solidly throughout their intervening spaces or where spaces are tightly closed by a continuous wood cover plate of not less than 2 inches nominal in thickness secured to the underside of the members. Splice plates shall be not less than 3 inches nominal in thickness.
  2. Where protected by approved automatic sprinklers under the roof deck, framing members shall be not less than 3 inches nominal in width.
Heavy timber structural members shall be detailed and constructed in accordance with Sections 2304.11.1 through 2304.11.1.3.
Minimum dimensions of columns shall be in accordance with Table 2304.11. Columns shall be continuous or superimposed throughout all stories and connected in an approved manner. Girders and beams at column connections shall be closely fitted around columns and adjoining ends shall be cross tied to each other, or intertied by caps or ties, to transfer horizontal loads across joints. Wood bolsters shall not be placed on tops of columns unless the columns support roof loads only. Where traditional heavy timber detailing is used, connections shall be by means of reinforced concrete or metal caps with brackets, by properly designed steel or iron caps, with pintles and base plates, by timber splice plates affixed to the columns by metal connectors housed within the contact faces, or by other approved methods.
Minimum dimensions of floor framing shall be in accordance with Table 2304.11. Approved wall plate boxes or hangers shall be provided where wood beams, girders or trusses rest on masonry or concrete walls. Where intermediate beams are used to support a floor, they shall rest on top of girders, or shall be supported by an approved metal hanger into which the ends of the beams shall be closely fitted. Where traditional heavy timber detailing is used, these connections shall be permitted to be supported by ledgers or blocks securely fastened to the sides of the girders.
Minimum dimensions of roof framing shall be in accordance with Table 2304.11. Every roof girder and not less than every alternate roof beam shall be anchored to its supporting member to resist forces as required in Chapter 16.
Exterior walls shall bepermitted to be cross-laminated timber not less than 4 inches (102 mm) in thickness meeting the requirements of Section 2303.1.4.
Interior walls and partitions shall be of solid wood construction formed by not less than two layers of 1-inch (25 mm) matched boards or laminated construction 4 inches (102 mm) thick, or of 1-hour fire-resistance-rated construction.
Floors shall be without concealed spaces or with concealed spaces complying with Section 602.4.4.3. Wood floors shall be constructed in accordance with Section 2304.11.3.1 or 2304.11.3.2.
Cross-laminated timber shall be not less than 4 inches (102 mm) in actual thickness. Cross-laminated timber shall be continuous from support to support and mechanically fastened to one another. Cross-laminated timber shall be permitted to be connected to walls without a shrinkage gap providing swelling or shrinking is considered in the design. Corbelling of masonry walls under the floor shall be permitted to be used.

Sawn or glued-laminated plank floors shall be one of the following:

  1. Sawn or glued-laminated planks, splined or tongue-and-groove, of not less than 3 inches (76 mm) nominal in thickness covered with 1-inch (25 mm) nominal dimension tongue-and-groove flooring, laid crosswise or diagonally, 15/32-inch (12 mm) wood structural panel or 1/2-inch (12.7 mm) particleboard.
  2. Planks not less than 4 inches (102 mm) nominal in width set on edge close together and well spiked and covered with 1-inch (25 mm) nominal dimension flooring or 15/32-inch (12 mm) wood structural panel or 1/2-inch (12.7 mm) particleboard.

The lumber shall be laid so that continuous lines of joints will occur only at points of support. Floors shall not extend closer than 1/2 inch (12.7 mm) to walls. Such 1/2-inch (12.7 mm) space shall be covered by a molding fastened to the wall and so arranged that it will not obstruct the swelling or shrinkage movements of the floor. Corbelling of masonry walls under the floor shall be permitted to be used in place of molding.

Roofs shall be without concealed spaces or with concealed spaces complying with Section 602.4.4.3. Roof decks shall be constructed in accordance with Section 2304.11.4.1 or 2304.11.4.2. Other types of decking shall be an alternative that provides equivalent fire resistance and structural properties. Where supported by a wall, roof decks shall be anchored to walls to resist forces determined in accordance with Chapter 16. Such anchors shall consist of steel bolts, lags, screws or approved hardware of sufficient strength to resist prescribed forces.
Cross-laminated timber roofs shall be not less than 3 inches (76 mm) nominal in thickness and shall be continuous from support to support and mechanically fastened to one another.

Sawn, wood structural panel, or glued-laminated plank roofs shall be one of the following:

  1. Sawn or glued laminated, splined or tongue-and-groove plank, not less than 2 inches (51 mm) nominal in thickness.
  2. 11/8-inch-thick (32 mm) wood structural panel (exterior glue).
  3. Planks not less than 3 inches (76 mm) nominal in width, set on edge close together and laid as required for floors.
Wood shall be protected from decay and termites in accordance with the applicable provisions of Sections 2304.12.1 through 2304.12.4.
Wood used above ground in the locations specified in Sections 2304.12.1.1 through 2304.12.1.5 shall be naturally durable wood or preservative-treated wood using waterborne preservatives, in accordance with AWPA U1 for above-ground use.
Wood joists or wood structural floors that are closer than 18 inches (457 mm) or wood girders that are closer than 12 inches (305 mm) to the exposed ground in crawl spaces or unexcavated areas located within the perimeter of the building foundation shall be of naturally durable or preservative-treated wood.
Wood framing members, including wood sheathing, that are in contact with exterior foundation walls and are less than 8 inches (203 mm) from exposed earth shall be of naturally durable or preservative-treated wood.
Wood framing members and furring strips in direct contact with the interior of exterior masonry or concrete walls below grade shall be of naturally durable or preservative-treated wood.
Sleepers and sills on a concrete or masonry slab that is in direct contact with earth shall be of naturally durable or preservative-treated wood.
Clearance between wood siding and earth on the exterior of a building shall be not less than 6 inches (152 mm) or less than 2 inches (51 mm) vertical from concrete steps, porch slabs, patio slabs and similar horizontal surfaces exposed to the weather except where siding, sheathing and wall framing are of naturally durable or preservative-treated wood.
Wood used in the locations specified in Sections 2304.12.2.1 through 2304.12.2.8  shall be naturally durable wood or preservative-treated wood in accordance with AWPA U1. Preservative-treated wood used in interior locations shall be protected with two coats of urethane, shellac, latex epoxy or varnish unless waterborne preservatives are used. Prior to application of the protective finish, the wood shall be dried in accordance with the manufacturer's recommendations.
The ends of wood girders entering exterior masonry or concrete walls shall be provided with a 1/2-inch (12.7 mm) airspace on top, sides and end, unless naturally durable or preservative-treated wood is used.

Posts or columns supporting permanent structures and supported by a concrete or masonry slab or footing that is in direct contact with the earth shall be of naturally durable or preservative-treated wood.

Exception: Posts or columns that meet all of the following:

  1. Are not exposed to the weather, or are protected by a roof, eave, overhang, or other covering if exposed to the weather.
  2. Are supported by concrete piers or metal pedestals projected not less than 1 inch (25 mm) above the slab or deck and are separated from the concrete pier by an impervious moisture barrier.
  3. Are located not less than 8 inches (203 mm) above exposed earth.

Naturally durable or preservative-treated wood shall be utilized for those portions of wood members that form the structural supports of buildings, balconies, porches or similar permanent building appurtenances where such members are exposed to the weather without adequate protection from a roof, eave, overhang or other covering to prevent moisture or water accumulation on the surface or at joints between members.

Exception: Sawn lumber in buildings located in a geographical region where experience has demonstrated that climatic conditions preclude the need to use durable materials where the structure is exposed to the weather.

Wood structural members that support moisture-permeable floors or roofs that are exposed to the weather, such as concrete or masonry slabs, shall be of naturally durable or preservative-treated wood unless separated from such floors or roofs by an impervious moisture barrier. The impervious moisture barrier system protecting the structure supporting floors shall provide positive drainage of water that infiltrates the moisture-permeable floor topping.
Enclosed framing in exterior balconies and elevated walking surfaces that have weather-exposed surfaces shall be provided with openings that provide a net free cross-ventilation area not less than 1/150 of the area of each separate space.

Wood used in contact with exposed earth shall be naturally durable for both decay and termite resistance or preservative treated in accordance with AWPA U1 for soil or fresh water use.

Exception: Untreated wood is permitted where such wood is continuously and entirely below the ground-water level or submerged in fresh water.

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.
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.
Wood installed in retaining or crib walls shall be preservative treated in accordance with AWPA U1 for soil and fresh water use.

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.

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

The deflection of wood-frame diaphragms shall be determined in accordance with AWC SDPWS. The deflection (Δdia) 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)

For SI: Δdia = 0.052vL3/EAW + vL/4Gt + Len/1627 + ∑(xΔc)/2W

where:

= Area of chord cross section, in square inches (mm2).

E = Modulus of elasticity of diaphragm chords, in pounds per square inch (N/mm2).

en = Staple slip, in inches (mm) [see Table 2305.2(1)].

Gt = Panel rigidity through the thickness, in pounds per inch (N/mm) of panel width or depth [see Table 2305.2(2)].

L = Diaphragm length (dimension perpendicular to the direction of the applied load), in feet (mm).

v = Induced unit shear in pounds per linear foot (plf) (N/mm).

W = Diaphragm width [in the direction of applied force, in feet (mm)].

x = Distance from chord splice to nearest support, in feet (mm).

Δc  = Diaphragm chord splice slip at the induced unit shear, in inches (mm).

Δdia = Maximum mid-span diaphragm deflection determined by elastic analysis, in inches (mm).

TABLE 2305.2(1)

en VALUES (inches) FOR USE IN CALCULATING DIAPHRAGM AND SHEAR WALL DEFLECTION DUE TO FASTENER SLIP (Structural I)a, c

LOAD PER FASTENERb(pounds) FASTENER DESIGNATIONS
14-Ga staple × 2 inches long
60
0.011
80 0.018
100 0.028
120 0.04
140 0.053
160 0.068

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound = 4.448 N.

  1. Increase en values 20 percent for plywood grades other than Structural I.
  2. Load per fastener = maximum shear per foot divided by the number of fasteners per foot at interior panel edges.
  3. Decrease en values 50 percent for seasoned lumber (moisture content < 19 percent).

TABLE 2305.2(2)

VALUES OF Gt FOR USE IN CALCULATING DEFLECTION OF WOOD STRUCTURAL PANEL SHEAR WALLS AND DIAPHRAGMS

PANEL TYPE SPAN RATING VALUES OF Gt (lb/in. panel depth or width)
Structural Sheathing Structural I
Plywood OSB Plywood OSB
3-ply 4-ply 5-plya 3-ply 4-ply 5-plya
Sheathing 24/0 25,000 32,500 37,500 77,500 32,500 42,500 41,500 77,500
24/16 27,000 35,000 40,500 83,500 35,000 45,500 44,500 83,500
32/16 27,000 35,000 40,500 83,500 35,000 45,500 44,500 83,500
40/20 28,500 37,000 43,000 88,500 37,000 48,000 47,500 88,500
48/24 31,000 40,500 46,500 96,000 40,500 52,500 51,000 96,000
Single Floor 16 o.c. 27,000 35,000 40,500 83,500 35,000 45,500 44,500 83,500
20 o.c. 28,000 36,500 42,000 87,000 36,500 47,500 46,000 87,000
24 o.c. 30,000 39,000 45,000 93,000 39,000 50,500 49,500 93,000
32 o.c. 36,000 47,000 54,000 110,000 47,000 61,000 59,500 110,000
48 o.c. 50,500 65,500 76,000 155,000 65,500 85,000 83,500 155,000
Structural Sheathing Structural I
Thickness (in.) A-A, A-C Marine All Other Grades A-A, A-C Marine All Other Grades
Sanded Plywood 1/4 24,000 31,000 24,000 31,000 31,000 31,000
11/32 25,500 33,000 25,500 33,000 33,000 33,000
3/8 26,000 34,000 26,000 34,000 34,000 34,000
15/32 38,000 49,500 38,000 49,500 49,500 49,500
1/2 38,500 50,000 38,500 50,000 50,000 50,000
19/32 49,000 63,500 49,000 63,500 63,500 63,500
5/8 49,500 64,500 49,500 64,500 64,500 64,500
23/32 50,500 65,500 50,500 65,500 65,500 65,500
3/4 51,000 66,500 51,000 66,500 66,500 66,500
7/8 52,500 68,500 52,500 68,500 68,500 68,500
1 73,500 95,500 73,500 95,500 95,500 95,500
11/8 75,000 97,500 75,000 97,500 97,500 97,500

For SI: 1 inch = 25.4 mm, 1 pound/inch = 0.1751 N/mm.

  1. 5-ply applies to plywood with five or more layers. For 5-ply plywood with three layers, use values for 4-ply panels.

The deflection of wood-frame shear walls shall be determined in accordance with AWC SDPWS. The deflection (Δsw) of a blocked wood structural panel shear wall uniformly fastened throughout with staples is permitted to be calculated in accordance with Equation 23-2.

(Equation 23-2)

For SI: 

where:

A = Area of end-post cross section in square inches (mm2).

b = Shear wall length, in feet (mm).

da = Total vertical elongation of wall anchorage system (such as fastener slip, device elongation, rod elongation), in inches (mm), at the induced unit shear in the shear wall (v).

E = Modulus of elasticity of end posts, in pounds per square inch (N/mm2).

en = Staple slip, in inches (mm) [see Table 2305.2(1)].

Gt = Panel rigidity through the thickness, in pounds per inch (N/mm) of panel width or depth [see Table 2305.2(2)].

h = Shear wall height, in feet (mm).

v = Induced unit shear, in pounds per linear foot (N/mm).

Δsw = Maximum shear wall deflection determined by elastic analysis, in inches (mm).

The design and construction of wood elements in structures using allowable stress design shall be in accordance with the following applicable standards:

TABLE 2306.1

STANDARDS FOR DESIGN AND CONSTRUCTION OF WOOD ELEMENTS IN STRUCTURES USING ALLOWABLE STRESS DESIGN

STANDARDS PROMULGATOR STANDARD TITLE
American Wood Council
  ANSI/AWC NDS National Design Specification for Wood Construction
SDPWS Special Design Provisions for Wind and Seismic
American Society of Agricultural and Biological Engineers
  ASABE EP 484.3 Diaphragm Design of Metal-clad, Wood-Frame Rectangular Buildings
ASABE EP 486.3 Shallow Post and Pier Foundation Design
ASABE EP 559.1 Design Requirements and Bending Properties for Mechanically Laminated Wood Assemblies
APA—The Engineered Wood Association
  ANSI 117 Standard Specifications for Structural Glued Laminated Timber of Softwood Species
ANSI A190.1 Structural Glued Laminated Timber
  Panel Design Specification
  Plywood Design Specification Supplement 1—Design & Fabrication of Plywood Curved Panel
  Plywood Design Specification Supplement 2—Design & Fabrication of Glued Plywood-lumber Beams
  Plywood Design Specification Supplement 3—Design & Fabrication of Plywood Stressed-skin Panels
  Plywood Design Specification Supplement 4—Design & Fabrication of Plywood Sandwich Panels
  Plywood Design Specification Supplement 5—Design & Fabrication of All-plywood Beams
APA T300 Glulam Connection Details
APA S560 Field Notching and Drilling of Glued Laminated Timber Beams
APA S475 Glued Laminated Beam Design Tables
APA X450 Glulam in Residential Construction
APA X440 Product and Application Guide: Glulam
APA R540 Builders Tips: Proper Storage and Handling of Glulam Beams
Truss Plate Institute, Inc.
  TPI 1 National Design Standard for Metal Plate Connected Wood Truss Construction
West Coast Lumber Inspection Bureau
  AITC 104 Typical Construction Details
AITC 110 Standard Appearance Grades for Structural Glued Laminated Timber
AITC 113 Standard for Dimensions of Structural Glued Laminated Timber
AITC 119 Standard Specifications for Structural Glued Laminated Timber of Hardwood Species
AITC 200 Inspection Manual
The design of rafter spans is permitted to be in accordance with the AWC STJR.
The design of plank and beam flooring is permitted to be in accordance with the AWC Wood Construction Data No. 4.

The allowable unit stresses for preservative-treated wood need not be adjusted for treatment, but are subject to other adjustments.

The allowable unit stresses for fire-retardant-treated wood, including fastener values, shall be developed from an approved method of investigation that considers the effects of anticipated temperature and humidity to which the fire-retardant-treated wood will be subjected, the type of treatment and the redrying process. Other adjustments are applicable except that the impact load duration shall not apply.

The capacity of lumber decking arranged according to the patterns described in Section 2304.9.2 shall be the lesser of the capacities determined for moment and deflection according to the formulas in Table 2306.1.4.

TABLE 2306.1.4

ALLOWABLE LOADS FOR LUMBER DECKING

PATTERN ALLOWABLE AREA LOADa
Moment Deflection
Simple span
Two-span continuous
Combination simple- and two-span continuous
Cantilevered pieces intermixed
Controlled random layup
Mechanically laminated decking
2-inch decking
3-inch and 4-inch decking

For SI: 1 inch = 25.4 mm.

  1. wb = Allowable total uniform load limited by moment.

    wΔ = Allowable total uniform load limited by deflection.

    d = Actual decking thickness.

    l = Span of decking.

    Fb' = Allowable bending stress adjusted by applicable factors.

    E' = Modulus of elasticity adjusted by applicable factors.

Wood-frame diaphragms shall be designed and constructed in accordance with AWC SDPWS. Where panels are fastened to framing members with staples, requirements and limitations of AWC SDPWS shall be met and the allowable shear values set forth in Table 2306.2(1) or 2306.2(2) shall be permitted. The allowable shear values in Tables 2306.2(1) and 2306.2(2) are permitted to be increased 40 percent for wind design.

TABLE 2306.2(1)

ALLOWABLE SHEAR VALUES (POUNDS PER FOOT) FOR WOOD STRUCTURAL PANEL DIAPHRAGMS UTILIZING STAPLES WITH FRAMING OF DOUGLAS FIR-LARCH, OR SOUTHERN PINEaFOR WIND OR SEISMIC LOADINGf

PANEL GRADE STAPLE LENGTH AND GAGEd MINIMUM FASTENER PENETRATION IN FRAMING (inches) MINIMUM NOMINAL PANEL THICKNESS (inch) MINIMUM NOMINAL WIDTH OF FRAMING MEMBERS AT ADJOINING PANEL EDGES AND BOUNDARIESe (inches) BLOCKED DIAPHRAGMS UNBLOCKED DIAPHRAGMS
Fastener spacing (inches) at diaphragm boundaries (all cases) at continuous panel edges parallel to load (Cases 3, 4), and at all panel edges (Cases 5, 6)b Fasteners spaced 6 inches max. at supported edgesb
6 4 21/2c 2c Case 1 (No unblocked edges or continuous joints parallel to load) All other configurations (Cases 2, 3, 4, 5 and 6)g
Fastener spacing (inches) at other panel edges (Cases 1, 2, 3 and 4)b
6 6 4 3
Structural I grades 11/2 16 gage 1 3/8 2 175 235 350 400 155 115
3 200 265 395 450 175 130
15/32 2 175 235 350 400 155 120
3 200 265 395 450 175 130
Sheathing, single floor and other grades covered in DOC PS 1 and PS 2 11/2 16 gage 1 3/8 2 160 210 315 360 140 105
3 180 235 355 400 160 120
7/16 2 165 225 335 380 150 110
3 190 250 375 425 165 125
15/32 2 160 210 315 360 140 105
3 180 235 355 405 160 120
19/32 2 175 235 350 400 155 115
3 200 265 395 450 175 130

For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.

  1. 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.
  2. Space fasteners maximum 12 inches on center along intermediate framing members (6 inches on center where supports are spaced 48 inches on center).
  3. Framing at adjoining panel edges shall be 3 inches nominal or wider.
  4. Staples shall have a minimum crown width of 7/16 inch and shall be installed with their crowns parallel to the long dimension of the framing members.
  5. The minimum nominal width of framing members not located at boundaries or adjoining panel edges shall be 2 inches.
  6. 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.
  7. For Case 1 through 6 descriptions see Figure 2306.2(1).

FIGURE 2306.2(1)

CASES 1 THROUGH 6 FOR USE WITH TABLE 2306.2(1)

 

TABLE 2306.2(2)

ALLOWABLE SHEAR VALUES (POUNDS PER FOOT) FOR WOOD STRUCTURAL PANEL BLOCKED DIAPHRAGMS UTILIZING MULTIPLE ROWS OF STAPLES (HIGH-LOAD DIAPHRAGMS) WITH FRAMING OF DOUGLAS FIR-LARCH OR SOUTHERN PINEaFOR WIND OR SEISMIC LOADINGb, g, h

PANEL GRADEc STAPLE GAGEf MINIMUM FASTENER PENETRATION IN FRAMING (inches) MINIMUM NOMINAL PANEL THICKNESS (inch) MINIMUM NOMINAL WIDTH OF FRAMING MEMBER AT ADJOINING PANEL EDGES AND BOUNDARIESe LINES OF FASTENERS BLOCKED DIAPHRAGMS
Cases 1 and 2d
Fastener Spacing Per Line at Boundaries (inches)i
4 21/2 2
Fastener Spacing Per Line at Other Panel Edges (inches)i
6 4 4 3 3 2
Structural I grades 14 gage staples 2 15/32 3 2 600 600 860 960 1,060 1,200
4 3 860 900 1,160 1,295 1,295 1,400
19/32 3 2 600 600 875 960 1,075 1,200
4 3 875 900 1,175 1,440 1,475 1,795
Sheathing single floor and other grades covered in DOC PS 1 and PS 2 14 gage staples 2 15/32 3 2 540 540 735 865 915 1,080
4 3 735 810 1,005 1,105 1,105 1,195
19/32 3 2 600 600 865 960 1,065 1,200
4 3 865 900 1,130 1,430 1,370 1,485
23/32 4 3 865 900 1,130 1,490 1,430 1,545

For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.

  1. For framing of other species: (1) Find specific gravity for species of framing 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.
  2. Fastening along intermediate framing members: Space fasteners not greater than 12 inches on center, except 6 inches on center for spans greater than 32 inches.
  3. Panels conforming to DOC PS 1 or PS 2.
  4. This table gives shear values for Cases 1 and 2 as shown in Table 2306.2(1). The values shown are applicable to Cases 3, 4, 5 and 6 as shown in Table 2306.2(1), providing fasteners at all continuous panel edges are spaced in accordance with the boundary fastener spacing.
  5. The minimum nominal depth of framing members shall be 3 inches nominal. The minimum nominal width of framing members not located at boundaries or adjoining panel edges shall be 2 inches.
  6. Staples shall have a minimum crown width of 7/16 inch, and shall be installed with their crowns parallel to the long dimension of the framing members.
  7. High-load diaphragms shall be subject to special inspection in accordance with Section 1705.5.1.
  8. 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.
  9. For fastener spacing diagrams see Figure 2306.2(2).

For SI: 1 inch = 25.4 mm.

FIGURE 2306.2(2)

FASTENER SPACING DIAGRAMS FOR USE WITH TABLE 2306.2(2)

Wood-frame shear walls shall be designed and constructed in accordance with AWC SDPWS. Where panels are fastened to framing members with staples, requirements and limitations of AWC SDPWS shall be met and the allowable shear values set forth in Table 2306.3(1), 2306.3(2) or 2306.3(3) shall be permitted. The allowable shear values in Tables 2306.3(1) and 2306.3(2) are permitted to be increased 40 percent for wind design. Panels complying with ANSI/APA PRP-210 shall be permitted to use design values for Plywood Siding in the AWC SDPWS.

TABLE 2306.3(1)

ALLOWABLE SHEAR VALUES (POUNDS PER FOOT) FOR WOOD STRUCTURAL PANEL SHEAR WALLS UTILIZING STAPLES WITH FRAMING OF DOUGLAS FIR-LARCH OR SOUTHERN PINEa FOR WIND OR SEISMIC LOADINGb, f, g, i

PANEL GRADE MINIMUM NOMINAL PANEL THICKNESS (inch) MINIMUM FASTENER PENETRATION IN FRAMING (inches) PANELS APPLIED DIRECT TO FRAMING PANELS APPLIED OVER 1/2" OR 5/8" GYPSUM SHEATHING
Staple length and gageh (inches) Fastener spacing at panel edges (inches) Staple length and gageh (inches) Fastener spacing at panel edges (inches)
6 4 3 2d 6 4 3 2d
Structural I sheathing 3/8 1 11/2 16 Gage 155 235 315 400 2 16 Gage 155 235 310 400
7/16 170 260 345 440 155 235 310 400
15/32 185 280 375 475 155 235 300 400
Sheathing, plywood sidinge except Group 5 Species, ANSI/APA PRP 210sidinge 5/16c or 1/4c 1 11/2 16 Gage 145 220 295 375 2 16 Gage 110 165 220 285
3/8 140 210 280 360 140 210 280 360
7/16 155 230 310 395 140 210 280 360
15/32 170 255 335 430 140 210 280 360
19/32 13/4 16 Gage 185 280 375 475

For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.

  1. 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.
  2. 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 for 3/8-inch and 7/16-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.
  3. 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.
  4. Framing at adjoining panel edges shall be 3 inches nominal or wider.
  5. Values apply to all-veneer plywood. Thickness at point of fastening on panel edges governs shear values.
  6. 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.
  7. 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.
  8. Staples shall have a minimum crown width of 7/16 inch and shall be installed with their crowns parallel to the long dimension of the framing members.
  9. 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.

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

THICKNESS AND GRADE (inches) STAPLE GAGE AND DIMENSIONS ALLOWABLE SHEAR VALUE (pounds per linear foot) STAPLE SPACING AT PANEL EDGES (inches)a
4 3 2
1/2 or 25/32 Structural No. 16 gage galvanized staple, 7/16" crown 13/4 inches long 150 200 225
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.

  1. Fiberboard sheathing shall not be used to brace concrete or masonry walls.
  2. 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.
  3. Values shown are for fiberboard sheathing on one side only with long panel dimension either parallel or perpendicular to studs.
  4. Fastener shall be spaced 6 inches on center along intermediate framing members.
  5. Values are not permitted in Seismic Design Category D, E or F.

TABLE 2306.3(3)

ALLOWABLE SHEAR VALUES FOR WIND OR SEISMIC FORCES FOR SHEAR WALLS OF LATH AND PLASTER OR GYPSUM BOARD WOOD FRAMED WALL ASSEMBLIES UTILIZING STAPLES

TYPE OF MATERIAL THICKNESS OF MATERIAL WALL CONSTRUCTION STAPLE SPACINGb MAXIMUM (inches) SHEAR VALUEa, c (plf) MINIMUM STAPLE SIZE f, g
1. Expanded metal or woven wire lath and Portland cement plaster 7/8" Unblocked 6 180 No. 16 gage galv. staple, 7/8" legs
2. Gypsum lath, plain or perforated 3/8" lath and 1/2" plaster Unblocked 5 100 No. 16 gage galv. staple, 11/8" long
3. Gypsum sheathing 1/2" × 2' × 8' Unblocked 4 75 No. 16 gage galv. staple, 13/4" long
1/2" ×4' Blockedd

Unblocked
4

7
175 100
4. Gypsum board, gypsum veneer base or water-resistant gypsum backing board 1/2" Unblockedd 7 75 No. 16 gage galv. staple, 11/2" long
Unblockedd 4 110
Unblocked 7 100
Unblocked 4 125
Blockede 7 125
Blockede 4 150
5/8" Unblockedd 7 115 No. 16 gage galv. staple, 15/8" long
4 145
Blockede 7 145
4 175
Blockede

Two-ply
Base ply: 9

Face ply: 7
250 No. 16 gage galv. staple 15/8" long

No. 15 gage galv. staple, 21/4" long

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per foot = 14.5939 N/m.

  1. These shear walls shall not be used to resist loads imposed by masonry or concrete walls (see AWC SDPWS). Values shown are for short-term loading due to wind or seismic loading. Walls resisting seismic loads shall be subject to the limitations in Section 12.2.1 of ASCE 7. Values shown shall be reduced 25 percent for normal loading.
  2. Applies to fastening at studs, top and bottom plates and blocking.
  3. Except as noted, shear values are based on a maximum framing spacing of 16 inches on center.
  4. Maximum framing spacing of 24 inches on center.
  5. All edges are blocked, and edge fastening is provided at all supports and all panel edges.
  6. Staples shall have a minimum crown width of 7/16 inch, measured outside the legs, and shall be installed with their crowns parallel to the long dimension of the framing members.
  7. Staples for the attachment of gypsum lath and woven-wire lath shall have a minimum crown width of 3/4 inch, measured outside the legs.
The design and construction of wood elements and structures using load and resistance factor design shall be in accordance with ANSI/AWC NDS and AWC SDPWS.
The requirements of this section are intended for conventional light-frame construction. Other construction methods are permitted to be used, provided that a satisfactory design is submitted showing compliance with other provisions of this code. Interior nonload-bearing partitions, ceilings and curtain walls of conventional light-frame construction are not subject to the limitations of Section 2308.2. Detached one- and two-family dwellings and townhouses not more than three stories above grade plane in height with a separate means of egress and their accessory structures shall comply with the International Residential Code.
Where portions of a building of otherwise conventional light-frame construction exceed the limits of Section 2308.2, those portions and the supporting load path shall be designed in accordance with accepted engineering practice and the provisions of this code. For the purposes of this section, the term "portions" shall mean parts of buildings containing volume and area such as a room or a series of rooms. The extent of such design need only demonstrate compliance of the nonconventional light-framed elements with other applicable provisions of this code and shall be compatible with the performance of the conventional light-framed system.
Connectors and fasteners used in conventional construction shall comply with the requirements of Section 2304.10.
Buildings are permitted to be constructed in accordance with the provisions of conventional light-frame construction, subject to the limitations in Sections 2308.2.1 through 2308.2.6.
Structures of conventional light-frame construction shall be limited in story height in accordance with Table 2308.2.1.

TABLE 2308.2.1

ALLOWABLE STORY HEIGHT

SEISMIC DESIGN CATEGORY ALLOWABLE STORY ABOVE GRADE PLANE
A and B Three stories
C Two stories
D and Ea One story

For SI: 1 inch = 25.4 mm.

  1. For the purposes of this section, for buildings assigned to Seismic Design Category D or E, cripple walls shall be considered to be a story unless cripple walls are solid blocked and do not exceed 14 inches in height.
Maximum floor-to-floor height shall not exceed 11 feet, 7 inches (3531 mm). Exterior bearing wall and interior braced wall heights shall not exceed a stud height of 10 feet (3048 mm).

Loads shall be in accordance with Chapter 16 and shall not exceed the following:

  1. Average dead loads shall not exceed 15 psf (718 N/m2) for combined roof and ceiling, exterior walls, floors and partitions.

    Exceptions:

    1. Subject to the limitations of Section 2308.6.10, stone or masonry veneer up to the less of 5 inches (127 mm) thick or 50 pounds per square foot (2395 N/m2) and installed in accordance with Chapter 14 is permitted to a height of 30 feet (9144 mm) above a noncombustible foundation, with an additional 8 feet (2439) permitted for gable ends.
    2. Concrete or masonry fireplaces, heaters and chimneys shall be permitted in accordance with the provisions of this code.
  2. Live loads shall not exceed 40 psf (1916 N/m2) for floors.

    Exception: Live loads for concrete slab-on-ground floors in Risk Categories I and II shall be not more than 125 psf.

  3. Ground snow loads shall not exceed 50 psf (2395 N/m2).

V shall not exceed 130 miles per hour (57 m/s) (3-second gust).

Exceptions:

  1. V shall not exceed 140 mph (63 m/s) (3-second gust) for buildings in Exposure Category B that are not located in a hurricane-prone region.
  2. Where V exceeds 130 mph (3-second gust), the provisions of either AWC WFCM or ICC 600 are permitted to be used.
Ceiling joist and rafter framing constructed in accordance with Section 2308.7 and trusses shall not span more than 40 feet (12 192 mm) between points of vertical support. A ridge board in accordance with Section 2308.7 or 2308.7.3.1 shall not be considered a vertical support.
The use of the provisions for conventional light-frame construction in this section shall not be permitted for Risk Category IV buildings assigned to Seismic Design Category B, C, D or F.
Foundations and footings shall be designed and constructed in accordance with Chapter 18. Connections to foundations and footings shall comply with this section.
Foundation plates or sills resting on concrete or masonry foundations shall comply with Section 2304.3.1. Foundation plates or sills shall be bolted or anchored to the foundation with not less than 1/2-inch-diameter (12.7 mm) steel bolts or approved anchors spaced to provide equivalent anchorage as the steel bolts. Bolts shall be embedded not less than 7 inches (178 mm) into concrete or masonry. The bolts shall be located in the middle third of the width of the plate. Bolts shall be spaced not more than 6 feet (1829 mm) on center and there shall be not less than two bolts or anchor straps per piece with one bolt or anchor strap located not more than 12 inches (305 mm) or less than 4 inches (102 mm) from each end of each piece. Bolts in sill plates of braced wall lines in structures over two stories above grade shall be spaced not more than 4 feet (1219 mm) on center. A properly sized nut and washer shall be tightened on each bolt to the plate.
Sill plates along braced wall lines in buildings assigned to Seismic Design Category D shall be anchored with not less than 1/2-inch (12.7 mm) diameter anchor bolts with steel plate washers between the foundation sill plate and the nut, or approved anchor straps load-rated in accordance with Section 2304.10.4 and spaced to provide equivalent anchorage. Plate washers shall be not less than 0.229 inch by 3 inches by 3 inches (5.82 mm by 76 mm by 76 mm) in size. The hole in the plate washer is permitted to be diagonally slotted with a width of up to 3/16 inch (4.76 mm) larger than the bolt diameter and a slot length not to exceed 13/4 inches (44 mm), provided that a standard cut washer is placed between the plate washer and the nut.
Sill plates along braced wall lines in buildings assigned to Seismic Design Category E shall be anchored with not less than 5/8-inch diameter (15.9 mm) anchor bolts with steel plate washers between the foundation sill plate and the nut, or approved anchor straps load-rated in accordance with Section 2304.10.4 and spaced to provide equivalent anchorage. Plate washers shall be not less than 0.229 inch by 3 inches by 3 inches (5.82 mm by 76 mm by 76 mm) in size. The hole in the plate washer is permitted to be diagonally slotted with a width of up to 3/16 inch (4.76 mm) larger than the bolt diameter and a slot length not to exceed 13/4 inches (44 mm), provided that a standard cut washer is placed between the plate washer and the nut.
Floor framing shall comply with this section.

Girders for single-story construction or girders supporting loads from a single floor shall be not less than 4 inches by 6 inches (102 mm by 152 mm) for spans 6 feet (1829 mm) or less, provided that girders are spaced not more than 8 feet (2438 mm) on center. Other girders shall be designed to support the loads specified in this code. Girder end joints shall occur over supports.

Where a girder is spliced over a support, an adequate tie shall be provided. The ends of beams or girders supported on masonry or concrete shall not have less than 3 inches (76 mm) of bearing.

The allowable spans of girders that are fabricated of dimension lumber shall not exceed the values set forth in Table 2308.4.1.1(1) or 2308.4.1.1(2).

TABLE 2308.4.1.1(1)

HEADER AND GIRDER SPANSa, b FOR EXTERIOR BEARING WALLS
(Maximum spans for Douglas fir-larch, hem-fir, Southern pine and spruce-pine-fir and required number of jack studs)

GIRDERS AND HEADERS SUPPORTING SIZE GROUND SNOW LOAD (psf)e
30 50 70
Building widthc (feet)
12 24 36 12 24 36 12 24 36
Spanf NJd Spanf NJd Spanf NJd Spanf NJd Spanf NJd Spanf NJd Spanf NJd Spanf NJd Spanf NJd
Roof and ceiling 1-2 × 6 4-0 1 3-1 2 2-7 2 3-5 1 2-8 2 2-3 2 3-0 2 2-4 2 2-0 2
1-2 × 8 5-1 2 3-11 2 3-3 2 4-4 2 3-4 2 2-10 2 3-10 2 3-0 2 2-6 3
1-2 × 10 6-0 2 4-8 2 3-11 2 5-2 2 4-0 2 3-4 3 4-7 2 3-6 3 3-0 3
1-2 × 12 7-1 2 5-5 2 4-7 3 6-1 2 4-8 3 3-11 3 5-5 2 4-2 3 3-6 3
2-2 × 4 4-0 1 3-1 1 2-7 1 3-5 1 2-7 1 2-2 1 3-0 1 2-4 1 2-0 1
2-2 × 6 6-0 1 4-7 1 3-10 1 5-1 1 3-11 1 3-3 2 4-6 1 3-6 2 2-11 2
2-2 × 8 7-7 1 5-9 1 4-10 2 6-5 1 5-0 2 4-2 2 5-9 1 4-5 2 3-9 2
2-2 × 10 9-0 1 6-10 2 5-9 2 7-8 2 5-11 2 4-11 2 6-9 2 5-3 2 4-5 2
2-2 × 12 10-7 2 8-1 2 6-10 2 9-0 2 6-11 2 5-10 2 8-0 2 6-2 2 5-2 3
3-2 × 8 9-5 1 7-3 1 6-1 1 8-1 1 6-3 1 5-3 2 7-2 1 5-6 2 4-8 2
3-2 × 10 11-3 1 8-7 1 7-3 2 9-7 1 7-4 2 6-2 2 8-6 1 6-7 2 5-6 2
3-2 × 12 13-2 1 10-1 2 8-6 2 11-3 2 8-8 2 7-4 2 10-0 2 7-9 2 6-6 2
4-2 × 8 10-11 1 8-4 1 7-0 1 9-4 1 7-2 1 6-0 1 8-3 1 6-4 1 5-4 2
4-2 × 10 12-11 1 9-11 1 8-4 1 11-1 1 8-6 1 7-2 2 9-10 1 7-7 2 6-4 2
4-2 × 12 15-3 1 11-8 1 9-10 2 13-0 1 10-0 2 8-5 2 11-7 1 8-11 2 7-6 2
Roof, ceiling and one center-bearing floor 1-2 × 6 3-3 1 2-7 2 2-2 2 3-0 2 2-4 2 2-0 2 2-9 2 2-2 2 1-10 2
1-2 × 8 4-1 2 3-3 2 2-9 2 3-9 2 3-0 2 2-6 3 3-6 2 2-9 2 2-4 3
1-2 × 10 4-11 2 3-10 2 3-3 3 4-6 2 3-6 3 3-0 3 4-1 2 3-3 3 2-9 3
1-2 × 12 5-9 2 4-6 3 3-10 3 5-3 2 4-2 3 3-6 3 4-10 3 3-10 3 3-3 4
2-2 × 4 3-3 1 2-6 1 2-2 1 3-0 1 2-4 1 2-0 1 2-8 1 2-2 1 1-10 1
2-2 × 6 4-10 1 3-9 1 3-3 2 4-5 1 3-6 2 3-0 2 4-1 1 3-3 2 2-9 2
2-2 × 8 6-1 1 4-10 2 4-1 2 5-7 2 4-5 2 3-9 2 5-2 2 4-1 2 3-6 2
2-2 × 10 7-3 2 5-8 2 4-10 2 6-8 2 5-3 2 4-5 2 6-1 2 4-10 2 4-1 2
2-2 × 12 8-6 2 6-8 2 5-8 2 7-10 2 6-2 2 5-3 3 7-2 2 5-8 2 4-10 3
3-2 × 8 7-8 1 6-0 1 5-1 2 7-0 1 5-6 2 4-8 2 6-5 1 5-1 2 4-4 2
3-2 × 10 9-1 1 7-2 2 6-1 2 8-4 1 6-7 2 5-7 2 7-8 2 6-1 2 5-2 2
3-2 × 12 10-8 2 8-5 2 7-2 2 9-10 2 7-8 2 6-7 2 9-0 2 7-1 2 6-1 2
4-2 × 8 8-10 1 6-11 1 5-11 1 8-1 1 6-4 1 5-5 2 7-5 1 5-11 1 5-0 2
4-2 × 10 10-6 1 8-3 2 7-0 2 9-8 1 7-7 2 6-5 2 8-10 1 7-0 2 6-0 2
4-2 × 12 12-4 1 9-8 2 8-3 2 11-4 2 8-11 2 7-7 2 10-4 2 8-3 2 7-0 2
Roof, ceiling and one clear span floor 1-2 × 6 2-11 2 2-3 2 1-11 2 2-9 2 2-1 2 1-9 2 2-7 2 2-0 2 1-8 2
1-2 × 8 3-9 2 2-10 2 2-5 3 3-6 2 2-8 2 2-3 3 3-3 2 2-6 3 2-2 3
1-2 × 10 4-5 2 3-5 3 2-10 3 4-2 2 3-2 3 2-8 3 3-11 2 3-0 3 2-6 3
1-2 × 12 5-2 2 4-0 3 3-4 3 4-10 3 3-9 3 3-2 4 4-7 3 3-6 3 3-0 4
2-2 × 4 2-11 1 2-3 1 1-10 1 2-9 1 2-1 1 1-9 1 2-7 1 2-0 1 1-8 1
2-2 × 6 4-4 1 3-4 2 2-10 2 4-1 1 3-2 2 2-8 2 3-10 1 3-0 2 2-6 2
2-2 × 8 5-6 2 4-3 2 3-7 2 5-2 2 4-0 2 3-4 2 4-10 2 3-9 2 3-2 2
2-2 × 10 6-7 2 5-0 2 4-2 2 6-1 2 4-9 2 4-0 2 5-9 2 4-5 2 3-9 3
2-2 × 12 7-9 2 5-11 2 4-11 3 7-2 2 5-7 2 4-8 3 6-9 2 5-3 3 4-5 3
3-2 × 8 6-11 1 5-3 2 4-5 2 6-5 1 5-0 2 4-2 2 6-1 1 4-8 2 4-0 2
3-2 × 10 8-3 2 6-3 2 5-3 2 7-8 2 5-11 2 5-0 2 7-3 2 5-7 2 4-8 2
3-2 × 12 9-8 2 7-5 2 6-2 2 9-0 2 7-0 2 5-10 2 8-6 2 6-7 2 5-6 3
4-2 × 8 8-0 1 6-1 1 5-1 2 7-5 1 5-9 2 4-10 2 7-0 1 5-5 2 4-7 2
4-2 × 10 9-6 1 7-3 2 6-1 2 8-10 1 6-10 2 5-9 2 8-4 1 6-5 2 5-5 2
4-2 × 12 11-2 2 8-6 2 7-2 2 10-5 2 8-0 2 6-9 2 9-10 2 7-7 2 6-5 2
Roof, ceiling and two center-bearing floors 1-2 × 6 2-8 2 2-1 2 1-10 2 2-7 2 2-0 2 1-9 2 2-5 2 1-11 2 1-8 2
1-2 × 8 3-5 2 2-8 2 2-4 3 3-3 2 2-7 2 2-2 3 3-1 2 2-5 3 2-1 3
1-2 × 10 4-0 2 3-2 3 2-9 3 3-10 2 3-1 3 2-7 3 3-8 2 2-11 3 2-5 3
1-2 × 12 4-9 3 3-9 3 3-2 4 4-6 3 3-7 3 3-1 4 4-3 3 3-5 3 2-11 4
2-2 × 4 2-8 1 2-1 1 1-9 1 2-6 1 2-0 1 1-8 1 2-5 1 1-11 1 1-7 1
2-2 × 6 4-0 1 3-2 2 2-8 2 3-9 1 3-0 2 2-7 2 3-7 1 2-10 2 2-5 2
2-2 × 8 5-0 2 4-0 2 3-5 2 4-10 2 3-10 2 3-3 2 4-7 2 3-7 2 3-1 2
2-2 × 10 6-0 2 4-9 2 4-0 2 5-8 2 4-6 2 3-10 3 5-5 2 4-3 2 3-8 3
2-2 × 12 7-0 2 5-7 2 4-9 3 6-8 2 5-4 3 4-6 3 6-4 2 5-0 3 4-3 3
3-2 × 8 6-4 1 5-0 2 4-3 2 6-0 1 4-9 2 4-1 2 5-8 2 4-6 2 3-10 2
3-2 × 10 7-6 2 5-11 2 5-1 2 7-1 2 5-8 2 4-10 2 6-9 2 5-4 2 4-7 2
3-2 × 12 8-10 2 7-0 2 5-11 2 8-5 2 6-8 2 5-8 3 8-0 2 6-4 2 5-4 3
4-2 × 8 7-3 1 5-9 1 4-11 2 6-11 1 5-6 2 4-8 2 6-7 1 5-2 2 4-5 2
4-2 × 10 8-8 1 6-10 2 5-10 2 8-3 2 6-6 2 5-7 2 7-10 2 6-2 2 5-3 2
4-2 × 12 10-2 2 8-1 2 6-10 2 9-8 2 7-8 2 6-7 2 9-2 2 7-3 2 6-2 2
Roof, ceiling and two clear span floors 1-2 × 6 2-3 2 1-9 2 1-5 2 2-3 2 1-9 2 1-5 3 2-2 2 1-8 2 1-5 3
1-2 × 8 2-10 2 2-2 3 1-10 3 2-10 2 2-2 3 1-10 3 2-9 2 2-1 3 1-10 3
1-2 × 10 3-4 2 2-7 3 2-2 3 3-4 3 2-7 3 2-2 4 3-3 3 2-6 3 2-2 4
1-2 × 12 4-0 3 3-0 3 2-7 4 4-0 3 3-0 4 2-7 4 3-10 3 3-0 4 2-6 4
2-2 × 4 2-3 1 1-8 1 1-4 1 2-3 1 1-8 1 1-4 1 2-2 1 1-8 1 1-4 2
2-2 × 6 3-4 1 2-6 2 2-2 2 3-4 2 2-6 2 2-2 2 3-3 2 2-6 2 2-1 2
2-2 × 8 4-3 2 3-3 2 2-8 2 4-3 2 3-3 2 2-8 2 4-1 2 3-2 2 2-8 3
2-2 × 10 5-0 2 3-10 2 3-2 3 5-0 2 3-10 2 3-2 3 4-10 2 3-9 3 3-2 3
2-2 × 12 5-11 2 4-6 3 3-9 3 5-11 2 4-6 3 3-9 3 5-8 2 4-5 3 3-9 3
3-2 × 8 5-3 1 4-0 2 3-5 2 5-3 2 4-0 2 3-5 2 5-1 2 3-11 2 3-4 2
3-2 × 10 6-3 2 4-9 2 4-0 2 6-3 2 4-9 2 4-0 2 6-1 2 4-8 2 4-0 3
3-2 × 12 7-5 2 5-8 2 4-9 3 7-5 2 5-8 2 4-9 3 7-2 2 5-6 3 4-8 3
4-2 × 8 6-1 1 4-8 2 3-11 2 6-1 1 4-8 2 3-11 2 5-11 1 4-7 2 3-10 2
4-2 × 10 7-3 2 5-6 2 4-8 2 7-3 2 5-6 2 4-8 2 7-0 2 5-5 2 4-7 2
4-2 × 12 8-6 2 6-6 2 5-6 2 8-6 2 6-6 2 5-6 2 8-3 2 6-4 2 5-4 3

For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.

  1. Spans are given in feet and inches.
  2. Spans are based on minimum design properties for No. 2 grade lumber of Douglas fir-larch, hem-fir, Southern pine and spruce-pine fir.
  3. Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
  4. NJ = Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an approved framing anchor attached to the full-height wall stud and to the header.
  5. Use 30 psf ground snow load for cases in which ground snow load is less than 30 psf and the roof live load is equal to or less than 20 psf.
  6. Spans are calculated assuming the top of the header or girder is laterally braced by perpendicular framing. Where the top of the header or girder is not laterally braced (for example, cripple studs bearing on the header), tabulated spans for headers consisting of 2 × 8, 2 × 10, or 2 × 12 sizes shall be multiplied by 0.70 or the header or girder shall be designed.

TABLE 2308.4.1.1(2)

HEADER AND GIRDER SPANSa, b FOR INTERIOR BEARING WALLS
(Maximum spans for Douglas fir-larch, hem-fir, Southern pine and spruce-pine-fir and required number of jack studs)

HEADERS AND GIRDERS SUPPORTING SIZE BUILDING WIDTHc (feet)
12 24 36
Spane NJd Spane NJd Spane NJd
One floor only 2-2 × 4 4-1 1 2-10 1 2-4 1
2-2 × 6 6-1 1 4-4 1 3-6 1
2-2 × 8 7-9 1 5-5 1 4-5 2
2-2 × 10 9-2 1 6-6 2 5-3 2
2-2 × 12 10-9 1 7-7 2 6-3 2
3-2 × 8 9-8 1 6-10 1 5-7 1
3-2 × 10 11-5 1 8-1 1 6-7 2
3-2 × 12 13-6 1 9-6 2 7-9 2
4-2 × 8 11-2 1 7-11 1 6-5 1
4-2 × 10 13-3 1 9-4 1 7-8 1
4-2 × 12 15-7 1 11-0 1 9-0 2
Two floors 2-2 × 4 2-7 1 1-11 1 1-7 1
2-2 × 6 3-11 1 2-11 2 2-5 2
2-2 × 8 5-0 1 3-8 2 3-1 2
2-2 × 10 5-11 2 4-4 2 3-7 2
2-2 × 12 6-11 2 5-2 2 4-3 3
3-2 × 8 6-3 1 4-7 2 3-10 2
3-2 × 10 7-5 1 5-6 2 4-6 2
3-2 × 12 8-8 2 6-5 2 5-4 2
4-2 × 8 7-2 1 5-4 1 4-5 2
4-2 × 10 8-6 1 6-4 2 5-3 2
4-2 × 12 10-1 1 7-5 2 6-2 2

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

  1. Spans are given in feet and inches.
  2. Spans are based on minimum design properties for No. 2 grade lumber of Douglas fir-larch, hem-fir, Southern pine and spruce-pine fir.
  3. Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
  4. NJ = Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an approved framing anchor attached to the full-height wall stud and to the header.
  5. Spans are calculated assuming the top of the header or girder is laterally braced by perpendicular framing. Where the top of the header or girder is not laterally braced (for example, cripple studs bearing on the header), tabulated spans for headers consisting of 2 × 8, 2 × 10, or 2 × 12 sizes shall be multiplied by 0.70 or the header or girder shall be designed.
Floor joists shall comply with this section.
Spans for floor joists shall be in accordance with Table 2308.4.2.1(1), Table 2308.4.2.1(2) or the AWC STJR.

TABLE 2308.4.2.1(1)

FLOOR JOIST SPANS FOR COMMON LUMBER SPECIES
(Residential sleeping areas, live load = 30 psf, L/Δ = 360)

JOIST SPACING (inches) SPECIES AND GRADE DEAD LOAD = 10 psf DEAD LOAD = 20 psf
2 × 6 2 × 8 2 × 10 2 × 12 2 × 6 2 × 8 2 × 10 2 × 12
Maximum floor joist spans
(ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.)
12 Douglas Fir-Larch SS 12-6 16-6 21-0 25-7 12-6 16-6 21-0 25-7
Douglas Fir-Larch #1 12-0 15-10 20-3 24-8 12-0 15-7 19-0 22-0
Douglas Fir-Larch #2 11-10 15-7 19-10 23-0 11-6 14-7 17-9 20-7
Douglas Fir-Larch #3 9-8 12-4 15-0 17-5 8-8 11-0 13-5 15-7
Hem-Fir SS 11-10 15-7 19-10 24-2 11-10 15-7 19-10 24-2
Hem-Fir #1 11-7 15-3 19-5 23-7 11-7 15-2 18-6 21-6
Hem-Fir #2 11-0 14-6 18-6 22-6 11-0 14-4 17-6 20-4
Hem-Fir #3 9-8 12-4 15-0 17-5 8-8 11-0 13-5 15-7
Southern Pine SS 12-3 16-2 20-8 25-1 12-3 16-2 20-8 25-1
Southern Pine #1 11-10 15-7 19-10 24-2 11-10 15-7 18-7 22-0
Southern Pine #2 11-3 14-11 18-1 21-4 10-9 13-8 16-2 19-1
Southern Pine #3 9-2 11-6 14-0 16-6 8-2 10-3 12-6 14-9
Spruce-Pine-Fir SS 11-7 15-3 19-5 23-7 11-7 15-3 19-5 23-7
Spruce-Pine-Fir #1 11-3 14-11 19-0 23-0 11-3 14-7 17-9 20-7
Spruce-Pine-Fir #2 11-3 14-11 19-0 23-0 11-3 14-7 17-9 20-7
Spruce-Pine-Fir #3 9-8 12-4 15-0 17-5 8-8 11-0 13-5 15-7
16 Douglas Fir-Larch SS 11-4 15-0 19-1 23-3 11-4 15-0 19-1 23-0
Douglas Fir-Larch #1 10-11 14-5 18-5 21-4 10-8 13-6 16-5 19-1
Douglas Fir-Larch #2 10-9 14-1 17-2 19-11 9-11 12-7 15-5 17-10
Douglas Fir-Larch #3 8-5 10-8 13-0 15-1 7-6 9-6 11-8 13-6
Hem-Fir SS 10-9 14-2 18-0 21-11 10-9 14-2 18-0 21-11
Hem-Fir #1 10-6 13-10 17-8 20-9 10-4 13-1 16-0 18-7
Hem-Fir #2 10-0 13-2 16-10 19-8 9-10 12-5 15-2 17-7
Hem-Fir #3 8-5 10-8 13-0 15-1 7-6 9-6 11-8 13-6
Southern Pine SS 11-2 14-8 18-9 22-10 11-2 14-8 18-9 22-10
Southern Pine #1 10-9 14-2 18-0 21-4 10-9 13-9 16-1 19-1
Southern Pine #2 10-3 13-3 15-8 18-6 9-4 11-10 14-0 16-6
Southern Pine #3 7-11 10-10 12-1 14-4 7-1 8-11 10-10 12-10
Spruce-Pine-Fir SS 10-6 13-10 17-8 21-6 10-6 13-10 17-8 21-4
Spruce-Pine-Fir #1 10-3 13-6 17-2 19-11 9-11 12-7 15-5 17-10
Spruce-Pine-Fir #2 10-3 13-6 17-2 19-11 9-11 12-7 15-5 17-10
Spruce-Pine-Fir #3 8-5 10-8 13-0 15-1 7-6 9-6 11-8 13-6
19.2 Douglas Fir-Larch SS 10-8 14-1 18-0 21-10 10-8 14-1 18-0 21-0
Douglas Fir-Larch #1 10-4 13-7 16-9 19-6 9-8 12-4 15-0 17-5
Douglas Fir-Larch #2 10-1 12-10 15-8 18-3 9-1 11-6 14-1 16-3
Douglas Fir-Larch #3 7-8 9-9 11-10 13-9 6-10 8-8 10-7 12-4
Hem-Fir SS 10-1 13-4 17-0 20-8 10-1 13-4 17-0 20-7
Hem-Fir #1 9-10 13-0 16-4 19-0 9-6 12-0 14-8 17-0
Hem-Fir #2 9-5 12-5 15-6 17-1 8-11 11-4 13-10 16-1
Hem-Fir #3 7-8 9-9 11-10 13-9 6-10 8-8 10-7 12-4
Southern Pine SS 10-6 13-10 17-8 21-6 10-6 13-10 17-8 21-6
Southern Pine #1 10-1 13-4 16-5 19-6 9-11 12-7 14-8 17-5
Southern Pine #2 9-6 12-1 14-4 16-10 8-6 10-10 12-10 15-1
Southern Pine #3 7-3 9-1 11-0 13-1 6-5 8-2 9-10 11-8
Spruce-Pine-Fir SS 9-10 13-0 16-7 20-2 9-10 13-0 16-7 19-6
Spruce-Pine-Fir #1 9-8 12-9 15-8 18-3 9-1 11-6 14-1 16-3
Spruce-Pine-Fir #2 9-8 12-9 15-8 18-3 9-1 11-6 14-1 16-3
Spruce-Pine-Fir #3 7-8 9-9 11-10 13-9 6-10 8-8 10-7 12-4
24 Douglas Fir-Larch SS 9-11 13-1 16-8 20-3 9-11 13-1 16-2 18-9
Douglas Fir-Larch #1 9-7 12-4 15-0 17-5 8-8 11-0 13-5 15-7
Douglas Fir-Larch #2 9-1 11-6 14-1 16-3 8-1 10-3 12-7 14-7
Douglas Fir-Larch #3 6-10 8-8 10-7 12-4 6-2 7-9 9-6 11-0
Hem-Fir SS 9-4 12-4 15-9 19-2 9-4 12-4 15-9 18-5
Hem-Fir #1 9-2 12-0 14-8 17-0 8-6 10-9 13-1 15-2
Hem-Fir #2 8-9 11-4 13-10 16-1 8-0 10-2 12-5 14-4
Hem-Fir #3 6-10 8-8 10-7 12-4 6-2 7-9 9-6 11-0
Southern Pine SS 9-9 12-10 16-5 19-11 9-9 12-10 16-5 19-8
Southern Pine #1 9-4 12-4 14-8 17-5 8-10 11-3 13-1 15-7
Southern Pine #2 8-6 10-10 12-10 15-1 7-7 9-8 11-5 13-6
Southern Pine #3 6-5 8-2 9-10 11-8 5-9 7-3 8-10 10-5
Spruce-Pine-Fir SS 9-2 12-1 15-5 18-9 9-2 12-1 15-0 17-5
Spruce-Pine-Fir #1 8-11 11-6 14-1 16-3 8-1 10-3 12-7 14-7
Spruce-Pine-Fir #2 8-11 11-6 14-1 16-3 8-1 10-3 12-7 14-7
Spruce-Pine-Fir #3 6-10 8-8 10-7 12-4 6-2 7-9 9-6 11-0

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.

Note: Check sources for availability of lumber in lengths greater than 20 feet.


TABLE 2308.4.2.1(2)

FLOOR JOIST SPANS FOR COMMON LUMBER SPECIES
(Residential living areas, live load = 40 psf, L/Δ = 360)

JOIST SPACING (inches) SPECIES AND GRADE DEAD LOAD = 10 psf DEAD LOAD = 20 psf
2 × 6 2 × 8 2 × 10 2 × 12 2 × 6 2 × 8 2 × 10 2 × 12
Maximum floor joist spans
(ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.) (ft. - in.)
12 Douglas Fir-Larch SS 11-4 15-0 19-1 23-3 11-4 15-0 19-1 23-3
Douglas Fir-Larch #1 10-11 14-5 18-5 22-0 10-11 14-2 17-4 20-1
Douglas Fir-Larch #2 10-9 14-2 17-9 20-7 10-6 13-3 16-3 18-10
Douglas Fir-Larch #3 8-8 11-0 13-5 15-7 7-11 10-0 12-3 14-3
Hem-Fir SS 10-9 14-2 18-0 21-11 10-9 14-2 18-0 21-11
Hem-Fir #1 10-6 13-10 17-8 21-6 10-6 13-10 16-11 19-7
Hem-Fir #2 10-0 13-2 16-10 20-4 10-0 13-1 16-0 18-6
Hem-Fir #3 8-8 11-0 13-5 15-7 7-11 10-0 12-3 14-3
Southern Pine SS 11-2 14-8 18-9 22-10 11-2 14-8 18-9 22-10
Southern Pine #1 10-9 14-2 18-0 21-11 10-9 14-2 16-11 20-1
Southern Pine #2 10-3 13-6 16-2 19-1 9-10 12-6 14-9 17-5
Southern Pine #3 8-2 10-3 12-6 14-9 7-5 9-5 11-5 13-6
Spruce-Pine-Fir SS 10-6 13-10 17-8 21-6 10-6 13-10 17-8 21-6
Spruce-Pine-Fir #1 10-3 13-6 17-3 20-7 10-3 13-3 16-3 18-10
Spruce-Pine-Fir #2 10-3 13-6 17-3 20-7 10-3 13-3 16-3 18-10
Spruce-Pine-Fir #3 8-8 11-0 13-5 15-7 7-11 10-0 12-3 14-3
16 Douglas Fir-Larch SS 10-4 13-7 17-4 21-1 10-4 13-7 17-4 21-0
Douglas Fir-Larch #1 9-11 13-1 16-5 19-1 9-8 12-4 15-0 17-5
Douglas Fir-Larch #2 9-9 12-7 15-5 17-10 9-1 11-6 14-1 16-3
Douglas Fir-Larch #3 7-6 9-6 11-8 13-6 6-10 8-8 10-7 12-4
Hem-Fir SS 9-9 12-10 16-5 19-11 9-9 12-10 16-5 19-11
Hem-Fir #1 9-6 12-7 16-0 18-7 9-6 12-0 14-8 17-0
Hem-Fir #2 9-1 12-0 15-2 17-7 8-11 11-4 13-10 16-1
Hem-Fir #3 7-6 9-6 11-8 13-6 6-10 8-8 10-7 12-4
Southern Pine SS 10-2 13-4 17-0 20-9 10-2 13-4 17-0 20-9
Southern Pine #1 9-9 12-10 16-1 19-1 9-9 12-7 14-8 17-5
Southern Pine #2 9-4 11-10 14-0 16-6 8-6 10-10 12-10 15-1
Southern Pine #3 7-1 8-11 10-10 12-10 6-5 8-2 9-10 11-8
Spruce-Pine-Fir SS 9-6 12-7 16-0 19-6 9-6 12-7 16-0 19-6
Spruce-Pine-Fir #1 9-4 12-3 15-5 17-10 9-1 11-6 14-1 16-3
Spruce-Pine-Fir #2 9-4 12-3 15-5 17-10 9-1 11-6 14-1 16-3
Spruce-Pine-Fir #3 7-6 9-6 11-8 13-6 6-10 8-8 10-7 12-4
19.2 Douglas Fir-Larch SS 9-8 12-10 16-4 19-10 9-8 12-10 16-4 19-2
Douglas Fir-Larch #1 9-4 12-4 15-0 17-5 8-10 11-3 13-8 15-11
Douglas Fir-Larch #2 9-1 11-6 14-1 16-3 8-3 10-6 12-10 14-10
Douglas Fir-Larch #3 6-10 8-8 10-7 12-4 6-3 7-11 9-8 11-3
Hem-Fir SS 9-2 12-1 15-5 18-9 9-2 12-1 15-5 18-9
Hem-Fir #1 9-0 11-10 14-8 17-0 8-8 10-11 13-4 15-6
Hem-Fir #2 8-7 11-3 13-10 16-1 8-2 10-4 12-8 14-8
Hem-Fir #3 6-10 8-8 10-7 12-4 6-3 7-11 9-8 11-3
Southern Pine SS 9-6 12-7 16-0 19-6 9-6 12-7 16-0 19-6
Southern Pine #1 9-2 12-1 14-8 17-5 9-0 11-5 13-5 15-11
Southern Pine #2 8-6 10-10 12-10 15-1 7-9 9-10 11-8 13-9
Southern Pine #3 6-5 8-2 9-10 11-8