The provisions of this chapter shall govern the materials, design, construction and quality of wood members and their fasteners.
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. The design and construction of log structures shall be in accordance with the provisions of ICC 400.
The following terms are defined in Chapter 2:
CONVENTIONAL LIGHT-FRAME CONSTRUCTION.
DIAPHRAGM, UNBLOCKED.
DRAG STRUT.
GRADE (LUMBER).
NAILING, BOUNDARY.
NAILING, EDGE.
NAILING, FIELD.
NOMINAL SIZE (LUMBER).
STRUCTURAL GLUED-LAMINATED TIMBER.
TIE-DOWN (HOLD-DOWN).
Wood required by Section 2304.11 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.
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 D 2898).
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 also be provided with the shipment of trusses delivered to the job site. Truss design drawings shall include, at a minimum, the information specified below:
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; and
5.6. Environmental design criteria and loads (wind, rain, snow, seismic, etc.).
6. Other lateral loads, including drag strut loads;
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. Metal-connector-plate type, size and thickness or gage, and the dimensioned location of each metal connector plate 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; and
14. Required permanent individual truss member restraint location and the method and details of restraint/bracing to be used in accordance with Section 2303.4.1.2.
Where permanent restraint of truss members is required on the truss design drawings, it shall be accomplished by one of the following methods:
1. Permanent individual truss member restraint/bracing shall be installed using standard industry lateral restraint/bracing details in accordance with generally accepted engineering practice. Locations for lateral restraint shall be identified on the truss design drawing.
2. The trusses shall be designed so that the buckling of any individual truss member is resisted internally by the individual truss through suitable means (i.e., buckling reinforcement by T-reinforcement or L-reinforcement, proprietary reinforcement, etc.). The buckling reinforcement of individual members of the trusses shall be installed as shown on the truss design drawing or on supplemental truss member buckling reinforcement details provided by the truss designer.
3. A project-specific permanent individual truss member restraint/bracing design shall be permitted to be specified by any registered design professional.
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.
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. When 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.
Except as provided for in Section 1405 for weatherboarding or where stucco construction that complies with Section 2510 is installed, enclosed buildings shall be sheathed with one of the materials of the nominal thickness specified in Table 2304.6 or any other approved material of equivalent strength or durability.
TABLE 2304.6
MINIMUM THICKNESS OF WALL SHEATHING
SHEATHING TYPE | MINIMUM THICKNESS | MAXIMUM WALL STUD SPACING |
Wood boards | 5/8 inch | 24 inches on center |
Fiberboard | 1/2 inch | 16 inches on center |
Wood structural panel | In accordance with Tables 2308.9.3(2) and 2308.9.3(3) | — |
M-S “Exterior Glue“ and M-2 “Exterior Glue“ Particleboard | In accordance with Section 2306.3 and Table 2308.9.3(4) | — |
Gypsum sheathing | 1/2 inch | 16 inches on center |
Gypsum wallboard | 1/2 inch | 24 inches on center |
Reinforced cement mortar | 1 inch | 24 inches on center |
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 wall sheathing or siding used as structural sheathing shall be capable of resisting wind pressures in accordance with Section 1609. Maximum wind speeds for wood structural panel sheathing used to resist wind pressures shall be in accordance with Table 2304.6.1 for 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 NOMINAL 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 NOMINAL DESIGN WIND SPEED,Vasdd(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 |
Structural floor sheathing and structural roof sheathing shall comply with Sections 2304.7.1 and 2304.7.2, respectively.
TABLE 2304.7(1)
ALLOWABLE SPANS FOR LUMBER FLOOR AND ROOF SHEATHINGa, b
SPAN (inches) | MINIMUM NET THICKNESS (inches) OF LUMBER PLACED | |||
Perpendicular to supports | Diagonally to supports | |||
Surfaced dryc | Surfaced unseasoned | Surfaced dryc | 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 |
TABLE 2304.7(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 2304.7(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, b
SHEATHING GRADES | ROOFc | FLOORd | ||||
Panel span rating roof/ floor span | Panel thickness (inches) | Maximum span (inches) | Loade (psf) | Maximum span (inches) | ||
With edge supportf | 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 | 20g | 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 | 16h |
40/20 | 19/32, 5/8, 3/4, 7/8 | 40 | 32 | 40 | 30 | 20h,i |
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 | ROOFc | FLOORd | ||||
Panel span rating | Panel thickness (inches) | Maximum span (inches) | Loade (psf) | Maximum span (inches) | ||
With edge supportf | Without edge support | Total load | Live load | |||
16 o.c. | 1/2, 19/32, 5/8 | 24 | 24 | 50 | 40 | 16h |
20 o.c. | 19/32,5/8, 3/4 | 32 | 32 | 40 | 30 | 20h,i |
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 |
TABLE 2304.7(4)
ALLOWABLE SPAN FOR WOOD STRUCTURAL PANEL COMBINATION SUBFLOOR-UNDERLAYMENT (SINGLE FLOOR)a, b
(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 groupc | 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 ratingd | 16 o.c. | 20 o.c. | 24 o.c. | 32 o.c. | 48 o.c. |
TABLE 2304.7(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, b
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 | 35c | 45c | |
1/2 | 24 | 40c | 50c | |
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 | 40c | 50c | |
5/8 | 24 | 45c | 55c | |
23/32,3/4 | 24 | 60c | 65c |
Structural floor sheathing shall be designed in accordance with the general provisions of this code and the special provisions in this section.
Structural roof sheathing shall be designed in accordance with the general provisions of this code and the special provisions in this section.
The decking shall extend across a minimum of 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 at least two intervening courses. In the end bays, each piece shall bear on at least one support. Where an end joint occurs in an end bay, the next piece in the same course shall continue over the first inner support for at least 24 inches (610 mm). The details of the controlled random pattern shall be as specified for each decking material in Section 2304.8.3.3, 2304.8.4.3 or 2304.8.5.3.
The length of nails connecting laminations shall not be less than two and one-half times the net thickness of each lamination. Where decking supports are 48 inches (1219 mm) on center (o.c.) or less, side nails shall be installed not more than 30 inches (762 mm) o.c. 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) o.c., side nails shall be installed not more than 18 inches (457 mm) o.c. alternating between top and bottom edges and staggered one-third of the spacing in adjacent laminations. Two side nails shall be installed at each end of butt-jointed pieces.
Connections for wood members shall be designed in accordance with the appropriate methodology in Section 2301.2. The number and size of fasteners connecting wood members shall not be less than that set forth in Table 2304.9.1.
TABLE 2304.9.1
FASTENING SCHEDULE
CONNECTION | FASTENINGa, m | LOCATION | |
1. Joist to sill or girder | 3 - 8d common (21/2″× 0.131″) | toenail | |
3 - 3″× 0.131″nails | |||
3 - 3″14 gage staples | |||
2.Bridging to joist | 2 - 8d common (21/2″× 0.131″) | toenail each end | |
2 - 3″× 0.131″nails | |||
2 - 3″14 gage staples | |||
3. 1″× 6″subfloor or less to each joist | 2 - 8d common (21/2″× 0.131″) | face nail | |
4. Wider than 1″× 6″subfloor to each joist | 3 - 8d common (21/2″× 0.131″) | face nail | |
5. 2″subfloor to joist or girder | 2 - 16d common (31/2″× 0.162″) | blind and face nail | |
6. Sole plate to joist or blocking | 16d (31/2″× 0.135) at 16″o.c. | typical face nail | |
3″× 0.131″nails at 8″o.c. | |||
3″14 gage staples at 12″o.c. | |||
Sole plate to joist or blocking at braced wall panel | 3- 16d (31/2″× 0.135 at 16″o.c. | braced wall panels | |
4 - 3″× 0.131″nails at 16″o.c. | |||
4 - 3″14 gage staples at 16″o.c. | |||
7. Top plate to stud | 2 - 16d common (31/2″× 0.162″) | end nail | |
3 - 3″× 0.131″nails | |||
3 - 3″14 gage staples | |||
8. Stud to sole plate | 4 - 8d common (21/2″× 0.131″) | toenail | |
4 - 3″× 0.131″nails | |||
3 - 3″14 gage staples | |||
2 - 16d common (31/2″× 0.162″) | end nail | ||
3 - 3″× 0.131″nails | |||
3 - 3″14 gage staples | |||
9. Double studs | 16d (31/2″× 0.135″) at 24″o.c. | face nail | |
3″× 0.131″nail at 8″o.c. | |||
3″14 gage staple at 8″o.c. | |||
10. Double top plates | 16d (31/2″× 0.135″) at 16″o.c. | typical face nail | |
3″× 0.131″nail at 12″o.c. | |||
3″14 gage staple at 12″o.c. | |||
Double top plates | 8 - 16d common (31/2″× 0.162″) | lap splice | |
12 - 3″× 0.131″nails | |||
12 - 3″14 gage staples | |||
11. Blocking between joists or rafters to top plate | 3 - 8d common (21/2″× 0.131″) | toenail | |
3 - 3″× 0.131″nails | |||
3 - 3″14 gage staples | |||
12. Rim joist to top plate | 8d (21/2″× 0.131″) at 6″o.c. | toenail | |
3″× 0.131″nail at 6″o.c. | |||
3″14 gage staple at 6″o.c. | |||
13. Top plates, laps and intersections | 2 - 16d common (31/2″× 0.162″) | face nail | |
3 - 3″× 0.131″nails | |||
3 - 3″14 gage staples | |||
14. Continuous header, two pieces | 16d common (31/2″× 0.162″) | 16″ o.c. along edge | |
15. Ceiling joists to plate | 3 - 8d common (21/2″× 0.131″) | toenail | |
5 - 3″× 0.131″nails | |||
5 - 3″14 gage staples | |||
16. Continuous header to stud | 4 - 8d common (21/2″× 0.131″) | toenail |
(continued)
TABLE 2304.9.1—continued
FASTENING SCHEDULE
CONNECTION | FASTENINGa, m | LOCATION |
17. Ceiling joists, laps over partitions (see Section 2308.10.4.1, Table 2308.10.4.1) | 3 - 16d common (31/2″ × 0.162″) minimum, Table 2308.10.4.1 | face nail |
4 - 3″ × 0.131″ nails | ||
4 - 3″14 gage staples | ||
18. Ceiling joists to parallel rafters (see Section 2308.10.4.1, Table 2308.10.4.1) | 3 - 16d common (31/2″ × 0.162″) minimum, Table 2308.10.4.1 | face nail |
4 - 3″ × 0.131″ nails | ||
4 - 3″ 14 gage staples | ||
19. Rafter to plate (see Section 2308.10.1, Table 2308.10.1) | 3 - 8d common (21/2″ × 0.131″) | toenail |
3 - 3″ × 0.131″ nails | ||
3 - 3″14 gage staples | ||
20. 1″diagonal brace to each stud and plate | 2 - 8d common (21/2″ × 0.131″) 2 - 3″× 0.131″ nails 3 - 3″14 gage staples | face nail |
21. 1″ × 8″ sheathing to each bearing | 3 - 8d common (21/2″ × 0.131″) | face nail |
22. Wider than 1″ × 8″ sheathing to each bearing | 3 - 8d common (21/2″ × 0.131″) | face nail |
23. Built-up corner studs | 16d common (31/2″ × 0.162″) | 24″ o.c. |
3″ × 0.131″ nails | 16″ o.c. | |
3″14 gage staples | 16″ o.c. | |
24. Built-up girder and beams | 20d common (4″ × 0.192 32″ o.c. | face nail at top and bottom stag- gered on opposite sides |
3″× 0.131″nail at 24″ o.c. | ||
3″14 gage staple at 24″ o.c. | ||
2 - 20d common (4″ × 0.192″) | face nail at ends and at each splice | |
3 - 3″ × 0.131″ nails | ||
3 - 3″14 gage staples | ||
25. 2″ planks | 16d common (31/2″× 0.162″) | at each bearing |
26. Collar tie to rafter | 3 - 10d common (3″ × 0.148″) | face nail |
4 - 3″× 0.131″ nails | ||
4 - 3″14 gage staples | ||
27. Jack rafter to hip | 3 - 10d common (3″ × 0.148″) | toenail |
4 - 3″× 0.131″ nails | ||
4 - 3″14 gage staples | ||
2 - 16d common (31/2″ × 0.162″) | face nail | |
3 - 3″× 0.131″ nails | ||
3 - 3″14 gage staples | ||
28. Roof rafter to 2-by ridge beam | 2 - 16d common (31/2″ × 0.162″) | toenail |
3 - 3″× 0.131″ nails | ||
3 - 3″14 gage staples | ||
2 -16d common (31/2″ × 0.162″) | face nail | |
3 - 3″× 0.131″ nails | ||
3 - 3″14 gage staples | ||
29. Joist to band joist | 3 - 16d common (31/2″ × 0.162″) | face nail |
4 - 3″ × 0.131″ nails | ||
4 - 3″14 gage staples |
(continued)
TABLE 2304.9.1—continued
FASTENING SCHEDULE
CONNECTION | FASTENINGa, m | LOCATION | |
30. Ledger strip | 3 - 16d common (31/2″ × 0.162″) | face nail at each joist | |
4 - 3″ × 0.131″ nails | |||
4 - 3″14 gage staples | |||
31. Wood structural panels and particleboardb Subfloor, roof and wall sheathing (to framing) | 1/2″ and less | 6dc, 1 23/8″ × 0.113″ nailn | |
13/4″ 16 gageo | |||
19/32″to 3/4″ | 8dd or 6de | ||
23/8″ × 0.113″ nailp | |||
2″16 gagep | |||
8dc | |||
7/8″ to 1″ | 10dd or 8de | ||
11/8″ to 11/4″ | |||
Single floor (combination subfloor-underlayment to framing) | 3/4″ and less | 6de | |
7/8″ to 1″ | 8de | ||
11/8″ to 11/4″ | 10dd or 8de | ||
32. Panel siding (to framing) | 1/2″ or less | 6df | |
5/8″ | 8df | ||
33. Fiberboard sheathingg | 1/2″ | No. 11 gage roofing nailh | |
6d common nail (2″ × 0.113″) | |||
No. 16 gage staplei | |||
25/32″ | No. 11 gage roofing nailh | ||
8d common nail (21/2″ × 0.131″) | |||
No. 16 gage staplei | |||
34. Interior paneling | 1/4″ | 4dj | |
3/8″ | 6dk |
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. Fasteners other than nails, 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 B 695, 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, a minimum of ASTM A 653, type G185 zinc-coated galvanized steel, or equivalent, shall be 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.
1. Posts or columns that are either exposed to the weather or located in basements or cellars, supported by concrete piers or metal pedestals projected at least 1 inch (25 mm) above the slab or deck and 6 inches (152 mm) above exposed earth, and are separated therefrom by an impervious moisture barrier.
2. Posts or columns in enclosed crawl spaces or unexcavated areas located within the periphery of the building, supported by a concrete pier or metal pedestal at a height greater than 8 inches (203 mm) from exposed ground, and are separated therefrom by an impervious moisture barrier.
Wood used in contact with the ground (exposed earth) in the locations specified in Sections 2304.11.4.1 and 2304.11.4.2 shall be naturally durable (species for both decay and termite resistance) or preservative treated using water-borne preservatives in accordance with AWPA U1 (Commodity Specifications A or F) for soil or fresh water use.
Decks, fences, patios, planters, or other wooden building components that directly abut the sidewall of the foundation or structure shall be constructed so as to provide:
1. Eighteen-inch (457 mm) clearance beneath or,
2. Six-inch (152 mm) clearance between the top of the component and the exterior wall covering or,
3. Have components that are easily removable by screws or hinges to allow access for inspection of the foundation sidewall and treatment for termites.
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.
The provisions of Section 2603.9 shall apply to the installation of foam plastic insulation in close proximity to the ground.
Wood members supporting concrete, masonry or similar materials shall be checked for the effects of long-term loading using the provisions of the AF&PA 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.
The deflection of woodframe diaphragms shall be determined in accordance with AF&PA SDPWS. The deflection (Δ) 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) |
where:
A | = | Area of chord cross section, in square inches (mm2). |
b | = | Diaphragm width, in feet (mm). |
E | = | Elastic modulus of chords, in pounds per square inch (N/mm2). |
en | = | Staple deformation, 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, in feet (mm). |
v | = | Maximum shear due to design loads in the direction under consideration, in pounds per linear foot (plf) (N/mm). |
Δ | = | The calculated deflection, in inches (mm). |
Σ(ΔcX) | = | Sum of individual chord-splice slip values on both sides of the diaphragm, each multiplied by its distance to the nearest support. |
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 x 2 inches long | |
60 | 0.011 |
80 | 0.018 |
100 | 0.028 |
120 | 0.04 |
140 | 0.053 |
160 | 0.068 |
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) | |||||||
OTHER | STRUCTURAL I | ||||||||
3-ply Plywood | 4-ply Plywood | 5-ply Plywooda | OSB | 3-ply Plywood | 4-ply Plywood | 5-ply Plywooda | OSB | ||
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 |
OTHER | 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 |
The deflection of wood-frame shear walls shall be determined in accordance with AF&PA SDPWS. The deflection (Δ) 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) |
where:
A | = | Area of boundary element cross section in square inches (mm2) (vertical member at shear wall boundary). |
b | = | Wall width, in feet (mm). |
da | = | Vertical elongation of overturning anchorage (including fastener slip, device elongation, anchor rod elongation, etc.) at the design shear load (v). |
E | = | Elastic modulus of boundary element (vertical member at shear wall boundary), in pounds per square inch (N/mm2). |
en | = | Staple deformation, 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 | = | Wall height, in feet (mm). |
v | = | Maximum shear due to design loads at the top of the wall, in pounds per linear foot (N/mm). |
Δ | = | The calculated deflection, 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:
American Forest & Paper Association. | |
NDS | National Design Specification for Wood Construction |
SDPWS | Special Design Provisions for Wind and Seismic |
American Institute of Timber Construction. | |
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 117 | Standard Specifications for Structural Glued Laminated Timber of Softwood Species |
AITC 119 | Standard Specifications for Structural Glued Laminated Timber of Hardwood Species |
ANSI/ AITC A190.1 | Structural Glued Laminated Timber |
AITC 200 | Inspection Manual |
American Society of Agricultural and Biological Engineers. | |
ASABE EP 484.2 | Diaphragm Design of Metal-clad, Post-Frame Rectangular Buildings |
ASABE EP 486.1 | Shallow Post Foundation Design |
ASABE 559 | Design Requirements and Bending Properties for Mechanically Laminated Columns |
APA—The Engineered Wood Association. | |
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 | |
EWS T300 | Glulam Connection Details |
EWS S560 | Field Notching and Drilling of Glued Laminated Timber Beams |
EWS S475 | Glued Laminated Beam Design Tables |
EWS X450 | Glulam in Residential Construction |
EWS X440 | Product and Application Guide: Glulam |
EWS 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 |
The allowable unit stresses for preservative-treated wood need no adjustment for treatment, but are subject to other adjustments.
The capacity of lumber decking arranged according to the patterns described in Section 2304.8.2 shall be the lesser of the capacities determined for flexure and deflection according to the formulas in Table 2306.1.4.
TABLE 2306.1.4
ALLOWABLE LOADS FOR LUMBER DECKING
PATTERN | ALLOWABLE AREA LOADa, b | |
Flexure | 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 |
a. | σb | = | Allowable total uniform load limited by bending. |
σΔ | = | Allowable total uniform load limited by deflection. | |
b. | 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 AF&PA SDPWS. Where panels are fastened to framing members with staples, requirements and limitations of AF&PA 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 PINEa FOR 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 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) | |||||
Fastener spacing (inches) at other panel edges (Cases 1, 2, 3 and 4)b | ||||||||||
6 | 6 | 4 | 3 | |||||||
Structural I grades | 11/216 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 | 11/216 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 |
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 PINEa FOR 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) | |||||||||||
4 | 21/2 | 2 | |||||||||
Fastener Spacing Per Line at Other Panel Edges (inches) | |||||||||||
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 |
Wood-frame shear walls shall be designed and constructed in accordance with AF&PA SDPWS. Where panels are fastened to framing members with staples, requirements and limitations of AF&PA 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 AF&PA 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 sizeh | Fastener spacing at panel edges (inches) | Staple sizeh | Fastener spacing at panel edges (inches) | |||||||||
6 | 4 | 3 | 2d | 6 | 4 | 3 | 2d | |||||
Structural I sheathing | 3/8 | 1 | 11/216 Gage | 155 | 235 | 315 | 400 | 2 16 Gage | 155 | 235 | 310 | 400 |
Deleted | ||||||||||||
7/16 | 170 | 260 | 345 | 440 | 155 | 235 | 310 | 400 | ||||
Deleted | ||||||||||||
15/32 | 185 | 280 | 375 | 475 | 155 | 235 | 300 | 400 | ||||
Deleted | ||||||||||||
Sheathing, plywood sidinge except Group 5 Species, ANSI/APA PRP 210 siding | 5/16c or 1/4c | 1 | 11/2 16 Gage | 145 | 220 | 295 | 375 | 2 16 Gage | 110 | 165 | 220 | 285 |
Deleted | ||||||||||||
3/8 | 140 | 210 | 280 | 360 | 140 | 210 | 280 | 360 | ||||
Deleted | ||||||||||||
7/16 | 155 | 230 | 310 | 395 | 140 | 210 | 280 | 360 | ||||
Deleted | ||||||||||||
15/32 | 170 | 255 | 335 | 430 | 140 | 210 | 280 | 360 | ||||
Deleted | ||||||||||||
19/32 | 13/4 16 Gage | 185 | 280 | 375 | 475 | — | — | — | — | — |
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 | FASTENER SIZE | ALLOWABLE SHEAR VALUE (pounds per linear foot) STAPLE SPACING AT PANEL EDGES (inches)a | ||
4 | 3 | 2 | ||
1/2″ or 25/32″ Structural | No. 11 gage galvanized staple, 7/16″ crownf | 150 | 200 | 225 |
No. 11 gage galvanized staple, 1″ crownf | 220 | 290 | 325 |
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 SIZEf, 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, 1 1/8″ long |
3. Gypsum sheating | 1/2″ × 2' × 8' | Unblocked | 4 | 75 | No. 16 gage galv. staple, 1 3/4″ 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, 1 1/2″ 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, 1 1/2″ legs,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 1 5/8" long No. 15 gage galv. staple, 2 1/4" long | ||
Buildings are permitted to be constructed in accordance with the provisions of conventional light-frame construction, subject to the following limitations, and to further limitations of Sections 2308.11 and 2308.12.
1. Buildings shall be limited to a maximum of three stories above grade plane. For the purposes of this section, for buildings assigned to Seismic Design Category D or E, cripple stud walls shall be considered to be a story.
2. Maximum floor-to-floor height shall not exceed 11 feet, 7 inches (3531 mm). Bearing wall height shall not exceed a stud height of 10 feet (3048 mm).
3. Loads as determined in Chapter 16 shall not exceed the following:
3.1. Average dead loads shall not exceed 15 psf (718 N/m2) for combined roof and ceiling, exterior walls, floors and partitions.
1. Subject to the limitations of Sections 2308.11.2 and 2308.12.2, stone or masonry veneer up to the lesser of 5 inches (127 mm) thick or 50 psf (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 (2438 mm) permitted for gable ends.
2. Concrete or masonry fireplaces, heaters and chimneys shall be permitted in accordance with the provisions of this code.
3.2. Live loads shall not exceed 40 psf (1916 N/m2) for floors.
3.3. Ground snow loads shall not exceed 50 psf (2395 N/m2).
4. Ultimate design wind speeds, Vult shall not exceed 115 miles per hour (mph) (44 m/s) (3-second gust).
5. Roof trusses and rafters shall not span more than 40 feet (12 192 mm) between points of vertical support.
6. 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, E or F.
7. Conventional light-frame construction is limited in irregular structures assigned to Seismic Design Category D or E, as specified in Section 2308.12.6.
Buildings of conventional light-frame construction and assigned to Seismic Design Category B or C shall comply with the additional requirements in Section 2308.11.
Where joists and/or rafters are used, braced wall line top plates shall be fastened over the full length of the braced wall line to joists, rafters, rimboards or blocking above in accordance with Table 2304.9.1, Items 11, 12, 15 or 19, as applicable, based on the orientation of the joists or rafters to the braced wall line. Blocking at joists with walls above shall be equal to the depth of the joist at the braced wall line. Blocking at rafters need not be full depth but shall extend to within 2 inches (51 mm) from the roof sheathing above. Blocking shall be a minimum of 2 inches (51 mm) nominal thickness and shall be fastened to the braced wall line top plate as specified in Table 2304.9.1, Item 11. Notching or drilling of holes in blocking in accordance with the requirements of Section 2308.8.2 or Section 2308.10.4.2 shall be permitted.
Braced wall lines shall be supported by continuous foundations.
Girders for single-story construction or girders supporting loads from a single floor shall not be 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) o.c. Spans for built-up 2-inch (51 mm) girders shall be in accordance with Table 2308.9.5 or 2308.9.6. 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.
Spans for floor joists shall be in accordance with Table 2308.8(1) or 2308.8(2). For other grades and or species, refer to the AF&PA Span Tables for Joists and Rafters.
TABLE 2308.8(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 | |||||||
2x6 | 2x8 | 2x10 | 2x12 | 2x6 | 2x8 | 2x10 | 2x12 | |||
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 | 12-0 | 15-10 | 20-3 | 24-8 | 12-0 | 15-10 | 20-3 | 24-8 | |
Southern Pine | #2 | 11-10 | 15-7 | 19-10 | 24-2 | 11-10 | 15-7 | 18-7 | 21-9 | |
Southern Pine | #3 | 10-5 | 13-3 | 15-8 | 18-8 | 9-4 | 11-11 | 14-0 | 16-8 | |
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 | 10-11 | 14-5 | 18-5 | 22-5 | 10-11 | 14-5 | 17-11 | 21-4 | |
Southern Pine | #2 | 10-9 | 14-2 | 18-0 | 21-1 | 10-5 | 13-6 | 16-1 | 18-10 | |
Southern Pine | #3 | 9-0 | 11-6 | 13-7 | 16-2 | 8-1 | 10-3 | 12-2 | 14-6 | |
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 |
(continued)
TABLE 2308.8(1)—continued
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 | |||||||
2x6 | 2x8 | 2x10 | 2x12 | 2x6 | 2x8 | 2x10 | 2x12 | |||
Maximum floor joist spans | ||||||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
19.2 | Southern Pine | SS | 10-6 | 13-10 | 17-8 | 21-6 | 10-6 | 13-10 | 17-8 | 21-6 |
Southern Pine | #1 | 10-4 | 13-7 | 17-4 | 21-1 | 10-4 | 13-7 | 16-4 | 19-6 | |
Southern Pine | #2 | 10-1 | 13-4 | 16-5 | 19-3 | 9-6 | 12-4 | 14-8 | 17-2 | |
Southern Pine | #3 | 8-3 | 10-6 | 12-5 | 14-9 | 7-4 | 9-5 | 11-1 | 13-2 | |
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 | 19-11 | |
Southern Pine | #1 | 9-7 | 12-7 | 16-1 | 19-6 | 9-7 | 12-4 | 14-7 | 17-5 | |
Southern Pine | #2 | 9-4 | 12-4 | 14-8 | 17-2 | 8-6 | 11-0 | 13-1 | 15-5 | |
Southern Pine | #3 | 7-4 | 9-5 | 11-1 | 13-2 | 6-7 | 8-5 | 9-11 | 11-10 | |
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 | |
TABLE 2308.8(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 | |||||||
2x6 | 2x8 | 2x10 | 2x12 | 2x6 | 2x8 | 2x10 | 2x12 | |||
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 | 10-11 | 14-5 | 18-5 | 22-5 | 10-11 | 14-5 | 18-5 | 22-5 | |
Southern Pine | #2 | 10-9 | 14-2 | 18-0 | 21-9 | 10-9 | 14-2 | 16-11 | 19-10 | |
Southern Pine | #3 | 9-4 | 11-11 | 14-0 | 16-8 | 8-6 | 10-10 | 12-10 | 15-3 | |
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 | 9-11 | 13-1 | 16-9 | 20-4 | 9-11 | 13-1 | 16-4 | 19-6 | |
Southern Pine | #2 | 9-9 | 12-10 | 16-1 | 18-10 | 9-6 | 12-4 | 14-8 | 17-2 | |
Southern Pine | #3 | 8-1 | 10-3 | 12-2 | 14-6 | 7-4 | 9-5 | 11-1 | 13-2 | |
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 | 9-4 | 12-4 | 15-9 | 19-2 | 9-4 | 12-4 | 14-11 | 17-9 | |
Southern Pine | #2 | 9-2 | 12 -1 | 14-8 | 17-2 | 8-8 | 11-3 | 13-5 | 15-8 | |
Southern Pine | #3 | 7-4 | 9-5 | 11-1 | 13-2 | 6-9 | 8-7 | 10-1 | 12-1 | |
Spruce-Pine-Fir | SS | 9-0 | 11-10 | 15-1 | 18-4 | 9-0 | 11-10 | 15-1 | 17-9 | |
Spruce-Pine-Fir | #1 | 8-9 | 11-6 | 14-1 | 16-3 | 8-3 | 10-6 | 12-10 | 14-10 | |
Spruce-Pine-Fir | #2 | 8-9 | 11-6 | 14-1 | 16-3 | 8-3 | 10-6 | 12-10 | 14-10 | |
Spruce-Pine-Fir | #3 | 6-10 | 8-8 | 10-7 | 12-4 | 6-3 | 7-11 | 9-8 | 11-3 |
(continued)
TABLE 2308.8(2)—continued
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 | |||||||
2x6 | 2x8 | 2x10 | 2x12 | 2x6 | 2x8 | 2x10 | 2x12 | |||
Maximum floor joist spans | ||||||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
24 | Douglas Fir-Larch | SS | 9-0 | 11-11 | 15-2 | 18-5 | 9-0 | 11-11 | 14-9 | 17-1 |
Douglas Fir-Larch | #1 | 8-8 | 11-0 | 13-5 | 15-7 | 7-11 | 10-0 | 12-3 | 14-3 | |
Douglas Fir-Larch | #2 | 8-1 | 10-3 | 12-7 | 14-7 | 7-5 | 9-5 | 11-6 | 13-4 | |
Douglas Fir-Larch | #3 | 6-2 | 7-9 | 9-6 | 11-0 | 5-7 | 7-1 | 8-8 | 10-1 | |
Hem-Fir | SS | 8-6 | 11-3 | 14-4 | 17-5 | 8-6 | 11-3 | 14-4 | 16-10a | |
Hem-Fir | #1 | 8-4 | 10-9 | 13-1 | 15-2 | 7-9 | 9-9 | 11-11 | 13-10 | |
Hem-Fir | #2 | 7-11 | 10-2 | 12-5 | 14-4 | 7-4 | 9-3 | 11-4 | 13-1 | |
Hem-Fir | #3 | 6-2 | 7-9 | 9-6 | 11-0 | 5-7 | 7-1 | 8-8 | 10-1 | |
Southern Pine | SS | 8-10 | 11-8 | 14-11 | 18-1 | 8-10 | 11-8 | 14-11 | 18-1 | |
Southern Pine | #1 | 8-8 | 11-5 | 14-7 | 17-5 | 8-8 | 11-3 | 13-4 | 15-11 | |
Southern Pine | #2 | 8-6 | 11-0 | 13-1 | 15-5 | 7-9 | 10-0 | 12-0 | 14-0 | |
Southern Pine | #3 | 6-7 | 8-5 | 9-11 | 11-10 | 6-0 | 7-8 | 9-1 | 10-9 | |
Spruce-Pine-Fir | SS | 8-4 | 11-0 | 14-0 | 17-0 | 8-4 | 11-0 | 13-8 | 15-11 | |
Spruce-Pine-Fir | #1 | 8-1 | 10-3 | 12-7 | 14-7 | 7-5 | 9-5 | 11-6 | 13-4 | |
Spruce-Pine-Fir | #2 | 8-1 | 10-3 | 12-7 | 14-7 | 7-5 | 9-5 | 11-6 | 13-4 | |
Spruce-Pine-Fir | #3 | 6-2 | 7-9 | 9-6 | 11-0 | 5-7 | 7-1 | 8-8 | 10-1 | |
Joists shall be supported laterally at the ends and at each support by solid blocking except where the ends of the joists are nailed to a header, band or rim joist or to an adjoining stud or by other means. Solid blocking shall not be less than 2 inches (51mm) in thickness and the full depth of the joist. Notches on the ends of joists shall not exceed one-fourth the joist depth. Holes bored in joists shall not be within 2 inches (51 mm) of the top or bottom of the joist, and the diameter of any such hole shall not exceed one-third the depth of the joist. Notches in the top or bottom of joists shall not exceed one-sixth the depth and shall not be located in the middle third of the span.
The size, height and spacing of studs shall be in accordance with Table 2308.9.1 except that utility-grade studs shall not be spaced more than 16 inches (406 mm) o.c., or support more than a roof and ceiling, or exceed 8 feet (2438 mm) in height for exterior walls and load-bearing walls or 10 feet (3048 mm) for interior nonload-bearing walls. Studs shall be continuous from a support at the sole plate to a support at the top plate to resist loads perpendicular to the wall. The support shall be a foundation or floor, ceiling or roof diaphragm or shall be designed in accordance with accepted engineering practice.
TABLE 2308.9.1
SIZE, HEIGHT AND SPACING OF WOOD STUDS
STUD SIZE (inches) | BEARING WALLS | NONBEARING WALLS | ||||
Laterally unsupported stud heighta (feet) | Supporting roof and ceiling only | Supporting one floor, roof and ceiling | Supporting two floors, roof and ceiling | Laterally unsupported stud heighta (feet) | Spacing (inches) | |
Spacing (inches) | ||||||
2 × 3b | — | — | — | — | 10 | 16 |
2 × 4 | 10 | 24 | 16 | — | 14 | 24 |
3 × 4 | 10 | 24 | 24 | 16 | 14 | 24 |
2 × 5 | 10 | 24 | 24 | — | 16 | 24 |
2 × 6 | 10 | 24 | 24 | 16 | 20 | 24 |
Studs shall be placed with their wide dimension perpendicular to the wall. Not less than three studs shall be installed at each corner of an exterior wall.
Bearing and exterior wall studs shall be capped with double top plates installed to provide overlapping at corners and at intersections with other partitions. End joints in double top plates shall be offset at least 48 inches (1219 mm), and shall be nailed with not less than eight 16d face nails on each side of the joint. Plates shall be a nominal 2 inches (51 mm) in depth and have a width at least equal to the width of the studs.
Braced wall lines shall consist of braced wall panels that meet the requirements for location, type and amount of bracing as shown in Figure 2308.9.3, specified in Table 2308.9.3(1) and are in line or offset from each other by not more than 4 feet (1219 mm). Braced wall panels shall start not more than 121/2 feet (3810 mm) from each end of a braced wall line. Braced wall panels shall be clearly indicated on the plans. Construction of braced wall panels shall be by one of the following methods:
1. Nominal 1-inch by 4-inch (25 mm by 102 mm) continuous diagonal braces let into top and bottom plates and intervening studs, placed at an angle not more than 60 degrees (1.0 rad) or less than 45 degrees (0.79 rad) from the horizontal and attached to the framing in conformance with Table 2304.9.1.
2. Wood boards of 5/8 inch (15.9 mm) net minimum thickness applied diagonally on studs spaced not over 24 inches (610 mm) o.c.
3. Wood structural panel sheathing with a thickness not less than 3/8 inch (9.5 mm) for 16-inch (406 mm) or 24-inch (610 mm) stud spacing in accordance with Tables 2308.9.3(2) and 2308.9.3(3).
4. Fiberboard sheathing panels not less than 1/2 inch (12.7 mm) thick applied vertically or horizontally on studs spaced not over 16 inches (406 mm) o.c. where installed with fasteners in accordance with Section 2306.6 and Table 2306.6.
5. Gypsum board [sheathing 1/2-inch-thick (12.7 mm) by 4-feet-wide (1219 mm) wallboard or veneer base] on studs spaced not over 24 inches (610 mm) o.c. and nailed at 7 inches (178 mm) o.c. with nails as required by Table 2306.7.
6. Particleboard wall sheathing panels where installed in accordance with Table 2308.9.3(4).
7. Portland cement plaster on studs spaced 16 inches (406 mm) o.c.installed in accordance with Section 2510.
8. Hardboard panel siding where installed in accordance with Section 2303.1.6 and Table 2308.9.3(5).
SEISMIC DESIGN CATEGORY | MAXIMUM WALL SPACING (feet) | REQUIRED BRACING LENGTH, b |
A, B and C | 35'-0″ | Table 2308.9.3(1) and Section 2308.9.3 |
D and E | 25'-0″ | Table 2308.12.4 |
FIGURE 2308.9.3
BASIC COMPONENTS OF THE LATERAL BRACING SYSTEM
TABLE 2308.9.3(1)
BRACED WALL PANELSa
SEISMIC DESIGN CATEGORY | CONDITION | CONSTRUCTION METHODSb, c | BRACED PANEL LOCATION AND LENGTHd | |||||||
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | |||
A and B | One story, top of two or three story | X | X | X | X | X | X | X | X | Located in accordance with Section 2308.9.3 and not more than 25 feet on center. |
First story of two story or second story of three story | X | X | X | X | X | X | X | X | ||
First story of three story | — | X | X | X | Xe | X | X | X | ||
C | One story or top of two story | — | X | X | X | X | X | X | X | Located in accordance with Section 2308.9.3 and not more than 25 feet on center. |
First story of two story | — | X | X | X | Xe | X | X | X | Located in accordance with Section 2308.9.3 and not more than 25 feet on center, but total length shall not be less than 25% of building lengthf. |
TABLE 2308.9.3(2)
EXPOSED PLYWOOD PANEL SIDING
MINIMUM THICKNESSa (inch) | MINIMUM NUMBER OF PLIES | STUD SPACING (inches) Plywood siding applied directly to studs or over sheathing |
3/8 | 3 | 16b |
1/2 | 4 | 24 |
TABLE 2308.9.3(3)
WOOD STRUCTURAL PANEL WALL SHEATHINGb
(Not Exposed to the Weather, Strength Axis Parallel or Perpendicular to Studs Except as Indicated Below)
MINIMUM THICKNESS (inch) | PANEL SPAN RATING | STUD SPACING (inches) | ||
Siding nailed to studs | Nailable sheathing | |||
Sheathing parallel to studs | Sheathing perpendicular to studs | |||
3/8, 15/32, 1/2 | 16/0, 20/0, 24/0, 32/16 Wall—24″ o.c. | 24 | 16 | 24 |
7/16, 15/32, 1/2 | 24/0, 24/16, 32/16 Wall—24″ o.c. | 24 | 24a | 24 |
TABLE 2308.9.3(4)
ALLOWABLE SPANS FOR PARTICLEBOARD WALL SHEATHING
(Not Exposed to the Weather, Long Dimension of the Panel Parallel or Perpendicular to Studs)
GRADE | THICKNESS (inch) | STUD SPACING (inches) | |
Siding nailed to studs | Sheathing under coverings specified in Section 2308.9.3 parallel or perpendicular to studs | ||
M-S “Exterior Glue“ and M-2 “Exterior Glue“ | 3/8 | 16 | — |
1/2 | 16 | 16 |
TABLE 2308.9.3(5)
HARDBOARD SIDING
SIDING | MINIMUM NOMINAL THICKNESS (inch) | 2 × 4 FRAMING MAXIMUM SPACING | NAIL SIZEa, b, d | NAIL SPACING | |
General | Bracing panelsc | ||||
1. Lap siding | |||||
Direct to studs | 3/8 | 16″ o.c. | 8d | 16″ o.c. | Not applicable |
Over sheathing | 3/8 | 16″ o.c. | 10d | 16″ o.c. | Not applicable |
2. Square edge panel siding | |||||
Direct to studs | 3/8 | 24″ o.c. | 6d | 6″ o.c. edges; 12″ o.c. at intermediate supports | 4″ o.c. edges; 8″ o.c. at intermediate supports |
Over sheathing | 3/8 | 24″ o.c. | 8d | 6″ o.c. edges; 12″ o.c. at intermediate supports | 4″ o.c. edges; 8″ o.c. at intermediate supports |
3. Shiplap edge panel siding | |||||
Direct to studs | 3/8 | 16″ o.c. | 6d | 6″ o.c. edges; 12″ o.c. at intermediate supports | 4″ o.c. edges; 8″ o.c. at intermediate supports |
Over sheathing | 3/8 | 16″ o.c. | 8d | 6″ o.c. edges; 12″ o.c. at intermediate supports | 4″ o.c. edges; 8″ o.c. at intermediate supports |
Panel Siding (inch) | Lap Siding (inch) | |
Shank diameter | 0.092 | 0.099 |
Head diameter | 0.225 | 0.240 |
Any bracing required by Section 2308.9.3 is permitted to be replaced by the following:
1. In one-story buildings, each panel shall have a length of not less than 2 feet 8 inches (813 mm) and a height of not more than 10 feet (3048 mm). Each panel shall be sheathed on one face with 3/8-inch-minimum-thickness (9.5 mm) wood structural panel sheathing nailed with 8d common or galvanized box nails in accordance with Table 2304.9.1 and blocked at wood structural panel edges. Two anchor bolts installed in accordance with Section 2308.6 shall be provided in each panel. Anchor bolts shall be placed at each panel outside quarter points. Each panel end stud shall have a tie-down device fastened to the foundation, capable of providing an approved uplift capacity of not less than 1,800 pounds (8006 N). The tie-down device shall be installed in accordance with the manufacturer’s recommendations. The panels shall be supported directly on a foundation or on floor framing supported directly on a foundation that is continuous across the entire length of the braced wall line. This foundation shall be reinforced with not less than one No. 4 bar top and bottom.
2. In the first story of two-story buildings, each wall panel shall be braced in accordance with Section 2308.9.3.1, Item 1, except that the wood structural panel sheathing shall be provided on both faces, three anchor bolts shall be placed at one-quarter points, and tie-down device uplift capacity shall not be less than 3,000 pounds (13 344 N).
Any bracing required by Section 2308.9.3 is permitted to be replaced by the following when used adjacent to a door or window opening with a full-length header:
1. In one-story buildings, each panel shall have a length of not less than 16 inches (406 mm) and a height of not more than 10 feet (3048 mm). Each panel shall be sheathed on one face with a single layer of 3/8 inch (9.5 mm) minimum thickness wood structural panel sheathing nailed with 8d common or galvanized box nails in accordance with Figure 2308.9.3.2. The wood structural panel sheathing shall extend up over the solid sawn or glued-laminated header and shall be nailed in accordance with Figure 2308.9.3.2. A built-up header consisting of at least two 2 × 12s and fastened in accordance with Item 24 of Table 2304.9.1 shall be permitted to be used. A spacer, if used, shall be placed on the side of the built-up beam opposite the wood structural panel sheathing. The header shall extend between the inside faces of the first full-length outer studs of each panel. The clear span of the header between the inner studs of each panel shall be not less than 6 feet (1829 mm) and not more than 18 feet (5486 mm) in length. A strap with an uplift capacity of not less than 1,000 pounds (4,400 N) shall fasten the header to the inner studs opposite the sheathing. One anchor bolt not less than 5/8 inch (15.9 mm) diameter and installed in accordance with Section 2308.6 shall be provided in the center of each sill plate. The studs at each end of the panel shall have a tie-down device fastened to the foundation with an uplift capacity of not less than 4,200 pounds (18 480 N).
2. In the first story of two-story buildings, each wall panel shall be braced in accordance with Item 1 above, except that each panel shall have a length of not less than 24 inches (610 mm).
FIGURE 2308.9.3.2
ALTERNATE BRACED WALL PANEL ADJACENT TO A DOOR OR WINDOW OPENING
Openings in exterior walls shall be constructed in accordance with Sections 2308.9.5.1 and 2308.9.5.2.
TABLE 2308.9.5
HEADER AND GIRDER SPANSa FOR EXTERIOR BEARING WALLS
(Maximum Spans for Douglas Fir-Larch, Hem-Fir, Southern Pine and Spruce-Pine-Firb and Required Number of Jack Studs)
HEADERS SUPPORTING | SIZE | GROUND SNOW LOAD (psf)e | |||||||||||
30 | 50 | ||||||||||||
Building widthc (feet) | |||||||||||||
20 | 28 | 36 | 20 | 28 | 36 | ||||||||
Span | NJd | Span | NJd | Span | NJd | Span | NJd | Span | NJd | Span | NJd | ||
Roof & Ceiling | 2-2×4 | 3-6 | 1 | 3-2 | 1 | 2-10 | 1 | 3-2 | 1 | 2-9 | 1 | 2-6 | 1 |
2-2×6 | 5-5 | 1 | 4-8 | 1 | 4-2 | 1 | 4-8 | 1 | 4-1 | 1 | 3-8 | 2 | |
2-2×8 | 6-10 | 1 | 5-11 | 2 | 5-4 | 2 | 5-11 | 2 | 5-2 | 2 | 4-7 | 2 | |
2-2×10 | 8-5 | 2 | 7-3 | 2 | 6-6 | 2 | 7-3 | 2 | 6-3 | 2 | 5-7 | 2 | |
2-2×12 | 9-9 | 2 | 8-5 | 2 | 7-6 | 2 | 8-5 | 2 | 7-3 | 2 | 6-6 | 2 | |
3-2×8 | 8-4 | 1 | 7-5 | 1 | 6-8 | 1 | 7-5 | 1 | 6-5 | 2 | 5-9 | 2 | |
3-2×10 | 10-6 | 1 | 9-1 | 2 | 8-2 | 2 | 9-1 | 2 | 7-10 | 2 | 7-0 | 2 | |
3-2×12 | 12-2 | 2 | 10-7 | 2 | 9-5 | 2 | 10-7 | 2 | 9-2 | 2 | 8-2 | 2 | |
4-2×8 | 9-2 | 1 | 8-4 | 1 | 7-8 | 1 | 8-4 | 1 | 7-5 | 1 | 6-8 | 1 | |
4-2×10 | 11-8 | 1 | 10-6 | 1 | 9-5 | 2 | 10-6 | 1 | 9-1 | 2 | 8-2 | 2 | |
4-2×12 | 14-1 | 1 | 12-2 | 2 | 10-11 | 2 | 12-2 | 2 | 10-7 | 2 | 9-5 | 2 | |
Roof, Ceiling & 1 Center-Bearing Floor | 2-2×4 | 3-1 | 1 | 2-9 | 1 | 2-5 | 1 | 2-9 | 1 | 2-5 | 1 | 2-2 | 1 |
2-2×6 | 4-6 | 1 | 4-0 | 1 | 3-7 | 2 | 4-1 | 1 | 3-7 | 2 | 3-3 | 2 | |
2-2×8 | 5-9 | 2 | 5-0 | 2 | 4-6 | 2 | 5-2 | 2 | 4-6 | 2 | 4-1 | 2 | |
2-2×10 | 7-0 | 2 | 6-2 | 2 | 5-6 | 2 | 6-4 | 2 | 5-6 | 2 | 5-0 | 2 | |
2-2×12 | 8-1 | 2 | 7-1 | 2 | 6-5 | 2 | 7-4 | 2 | 6-5 | 2 | 5-9 | 3 | |
3-2×8 | 7-2 | 1 | 6-3 | 2 | 5-8 | 2 | 6-5 | 2 | 5-8 | 2 | 5-1 | 2 | |
3-2×10 | 8-9 | 2 | 7-8 | 2 | 6-11 | 2 | 7-11 | 2 | 6-11 | 2 | 6-3 | 2 | |
3-2×12 | 10-2 | 2 | 8-11 | 2 | 8-0 | 2 | 9-2 | 2 | 8-0 | 2 | 7-3 | 2 | |
4-2×8 | 8-1 | 1 | 7-3 | 1 | 6-7 | 1 | 7-5 | 1 | 6-6 | 1 | 5-11 | 2 | |
4-2×10 | 10-1 | 1 | 8-10 | 2 | 8-0 | 2 | 9-1 | 2 | 8-0 | 2 | 7-2 | 2 | |
4-2×12 | 11-9 | 2 | 10-3 | 2 | 9-3 | 2 | 10-7 | 2 | 9-3 | 2 | 8-4 | 2 | |
Roof, Ceiling & 1 Clear Span Floor | 2-2×4 | 2-8 | 1 | 2-4 | 1 | 2-1 | 1 | 2-7 | 1 | 2-3 | 1 | 2-0 | 1 |
2-2×6 | 3-11 | 1 | 3-5 | 2 | 3-0 | 2 | 3-10 | 2 | 3-4 | 2 | 3-0 | 2 | |
2-2×8 | 5-0 | 2 | 4-4 | 2 | 3-10 | 2 | 4-10 | 2 | 4-2 | 2 | 3-9 | 2 | |
2-2×10 | 6-1 | 2 | 5-3 | 2 | 4-8 | 2 | 5-11 | 2 | 5-1 | 2 | 4-7 | 3 | |
2-2×12 | 7-1 | 2 | 6-1 | 3 | 5-5 | 3 | 6-10 | 2 | 5-11 | 3 | 5-4 | 3 | |
3-2×8 | 6-3 | 2 | 5-5 | 2 | 4-10 | 2 | 6-1 | 2 | 5-3 | 2 | 4-8 | 2 | |
3-2×10 | 7-7 | 2 | 6-7 | 2 | 5-11 | 2 | 7-5 | 2 | 6-5 | 2 | 5-9 | 2 | |
3-2×12 | 8-10 | 2 | 7-8 | 2 | 6-10 | 2 | 8-7 | 2 | 7-5 | 2 | 6-8 | 2 | |
4-2×8 | 7-2 | 1 | 6-3 | 2 | 5-7 | 2 | 7-0 | 1 | 6-1 | 2 | 5-5 | 2 | |
4-2×10 | 8-9 | 2 | 7-7 | 2 | 6-10 | 2 | 8-7 | 2 | 7-5 | 2 | 6-7 | 2 | |
4-2×12 | 10-2 | 2 | 8-10 | 2 | 7-11 | 2 | 9-11 | 2 | 8-7 | 2 | 7-8 | 2 |
(continued)
TABLE 2308.9.5—continued
HEADER AND GIRDER SPANSa FOR EXTERIOR BEARING WALLS
(Maximum Spans for Douglas Fir-Larch, Hem-Fir, Southern Pine and Spruce-Pine-Firb and Required Number of Jack Studs)
HEADERS SUPPORTING | SIZE | GROUND SNOW LOAD (psf)e | |||||||||||
30 | 50 | ||||||||||||
Building widthc (feet) | |||||||||||||
20 | 28 | 36 | 20 | 28 | 36 | ||||||||
Span | NJd | Span | NJd | Span | NJd | Span | NJd | Span | NJd | Span | NJd | ||
Roof, Ceiling & 2 Center- Bearing Floors | 2-2×4 | 2-7 | 1 | 2-3 | 1 | 2-0 | 1 | 2-6 | 1 | 2-2 | 1 | 1-11 | 1 |
2-2×6 | 3-9 | 2 | 3-3 | 2 | 2-11 | 2 | 3-8 | 2 | 3-2 | 2 | 2-10 | 2 | |
2-2×8 | 4-9 | 2 | 4-2 | 2 | 3-9 | 2 | 4-7 | 2 | 4-0 | 2 | 3-8 | 2 | |
2-2×10 | 5-9 | 2 | 5-1 | 2 | 4-7 | 3 | 5-8 | 2 | 4-11 | 2 | 4-5 | 3 | |
2-2×12 | 6-8 | 2 | 5-10 | 3 | 5-3 | 3 | 6-6 | 2 | 5-9 | 3 | 5-2 | 3 | |
3-2×8 | 5-11 | 2 | 5-2 | 2 | 4-8 | 2 | 5-9 | 2 | 5-1 | 2 | 4-7 | 2 | |
3-2×10 | 7-3 | 2 | 6-4 | 2 | 5-8 | 2 | 7-1 | 2 | 6-2 | 2 | 5-7 | 2 | |
3-2×12 | 8-5 | 2 | 7-4 | 2 | 6-7 | 2 | 8-2 | 2 | 7-2 | 2 | 6-5 | 3 | |
4-2×8 | 6-10 | 1 | 6-0 | 2 | 5-5 | 2 | 6-8 | 1 | 5-10 | 2 | 5-3 | 2 | |
4-2×10 | 8-4 | 2 | 7-4 | 2 | 6-7 | 2 | 8-2 | 2 | 7-2 | 2 | 6-5 | 2 | |
4-2×12 | 9-8 | 2 | 8-6 | 2 | 7-8 | 2 | 9-5 | 2 | 8-3 | 2 | 7-5 | 2 | |
Roof, Ceiling & 2 Clear Span Floors | 2-2×4 | 2-1 | 1 | 1-8 | 1 | 1-6 | 2 | 2-0 | 1 | 1-8 | 1 | 1-5 | 2 |
2-2×6 | 3-1 | 2 | 2-8 | 2 | 2-4 | 2 | 3-0 | 2 | 2-7 | 2 | 2-3 | 2 | |
2-2×8 | 3-10 | 2 | 3-4 | 2 | 3-0 | 3 | 3-10 | 2 | 3-4 | 2 | 2-11 | 3 | |
2-2×10 | 4-9 | 2 | 4-1 | 3 | 3-8 | 3 | 4-8 | 2 | 4-0 | 3 | 3-7 | 3 | |
2-2×12 | 5-6 | 3 | 4-9 | 3 | 4-3 | 3 | 5-5 | 3 | 4-8 | 3 | 4-2 | 3 | |
3-2×8 | 4-10 | 2 | 4-2 | 2 | 3-9 | 2 | 4-9 | 2 | 4-1 | 2 | 3-8 | 2 | |
3-2×10 | 5-11 | 2 | 5-1 | 2 | 4-7 | 3 | 5-10 | 2 | 5-0 | 2 | 4-6 | 3 | |
3-2×12 | 6-10 | 2 | 5-11 | 3 | 5-4 | 3 | 6-9 | 2 | 5-10 | 3 | 5-3 | 3 | |
4-2×8 | 5-7 | 2 | 4-10 | 2 | 4-4 | 2 | 5-6 | 2 | 4-9 | 2 | 4-3 | 2 | |
4-2×10 | 6-10 | 2 | 5-11 | 2 | 5-3 | 2 | 6-9 | 2 | 5-10 | 2 | 5-2 | 2 | |
4-2×12 | 7-11 | 2 | 6-10 | 2 | 6-2 | 3 | 7-9 | 2 | 6-9 | 2 | 6-0 | 3 |
Headers shall be provided over each opening in interior bearing partitions as required in Section 2308.9.5. The spans in Table 2308.9.6 are permitted to be used. Wall studs shall support the ends of the header in accordance with Table 2308.9.5 or 2308.9.6, as appropriate.
TABLE 2308.9.6
HEADER AND GIRDER SPANSa FOR INTERIOR BEARING WALLS
(Maximum Spans for Douglas Fir-Larch, Hem-Fir, Southern Pine and Spruce-Pine-Firb and Required Number of Jack Studs)
HEADERS AND GIRDERS SUPPORTING | SIZE | BUILDING widthc (feet) | |||||
20 | 28 | 36 | |||||
Span | NJd | Span | NJd | Span | NJd | ||
One Floor Only | 2-2×4 | 3-1 | 1 | 2-8 | 1 | 2-5 | 1 |
2-2×6 | 4-6 | 1 | 3-11 | 1 | 3-6 | 1 | |
2-2×8 | 5-9 | 1 | 5-0 | 2 | 4-5 | 2 | |
2-2×10 | 7-0 | 2 | 6-1 | 2 | 5-5 | 2 | |
2-2×12 | 8-1 | 2 | 7-0 | 2 | 6-3 | 2 | |
3-2×8 | 7-2 | 1 | 6-3 | 1 | 5-7 | 2 | |
3-2×10 | 8-9 | 1 | 7-7 | 2 | 6-9 | 2 | |
3-2×12 | 10-2 | 2 | 8-10 | 2 | 7-10 | 2 | |
4-2×8 | 9-0 | 1 | 7-8 | 1 | 6-9 | 1 | |
4-2×10 | 10-1 | 1 | 8-9 | 1 | 7-10 | 2 | |
4-2×12 | 11-9 | 1 | 10-2 | 2 | 9-1 | 2 | |
Two Floors | 2-2×4 | 2-2 | 1 | 1-10 | 1 | 1-7 | 1 |
2-2×6 | 3-2 | 2 | 2-9 | 2 | 2-5 | 2 | |
2-2×8 | 4-1 | 2 | 3-6 | 2 | 3-2 | 2 | |
2-2×10 | 4-11 | 2 | 4-3 | 2 | 3-10 | 3 | |
2-2×12 | 5-9 | 2 | 5-0 | 3 | 4-5 | 3 | |
3-2×8 | 5-1 | 2 | 4-5 | 2 | 3-11 | 2 | |
3-2×10 | 6-2 | 2 | 5-4 | 2 | 4-10 | 2 | |
3-2×12 | 7-2 | 2 | 6-3 | 2 | 5-7 | 3 | |
4-2×8 | 6-1 | 1 | 5-3 | 2 | 4-8 | 2 | |
4-2×10 | 7-2 | 2 | 6-2 | 2 | 5-6 | 2 | |
4-2×12 | 8-4 | 2 | 7-2 | 2 | 6-5 | 2 |
A hole not greater in diameter than 40 percent of the stud width is permitted to be bored in any wood stud. Bored holes not greater than 60 percent of the width of the stud are permitted in nonbearing partitions or in any wall where each bored stud is doubled, provided not more than two such successive doubled studs are so bored.
The roof construction shall have rafter and truss ties to the wall below. Resultant uplift loads shall be transferred to the foundation using a continuous load path. The rafter or truss to wall connection shall comply with Tables 2304.9.1 and 2308.10.1.
TABLE 2308.10.1
REQUIRED RATING OF APPROVED UPLIFT CONNECTORS (pounds)a, b, c, e, f, g, h
NOMINAL DESIGN WIND SPEED,Vasdi | ROOF SPAN (feet) | OVERHANGS (pounds/feet)d | ||||||
12 | 20 | 24 | 28 | 32 | 36 | 40 | ||
85 | -72 | -120 | -145 | -169 | -193 | -217 | -241 | -38.55 |
90 | -91 | -151 | -181 | -212 | -242 | -272 | -302 | -43.22 |
100 | -131 | -281 | -262 | -305 | -349 | -393 | -436 | -53.36 |
110 | -175 | -292 | -351 | -409 | -467 | -526 | -584 | -64.56 |
Mean Roof Height (feet) | ||||||||||
EXPOSURE | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 |
B | 1.00 | 1.00 | 1.00 | 1.00 | 1.05 | 1.09 | 1.12 | 1.16 | 1.19 | 1.22 |
C | 1.21 | 1.29 | 1.35 | 1.40 | 1.45 | 1.49 | 1.53 | 1.56 | 1.59 | 1.62 |
D | 1.47 | 1.55 | 1.61 | 1.66 | 1.70 | 1.74 | 1.78 | 1.81 | 1.84 | 1.87 |
Allowable spans for ceiling joists shall be in accordance with Table 2308.10.2(1) or 2308.10.2(2). For other grades and species, refer to the AF&PA Span Tables for Joists and Rafters.
TABLE 2308.10.2(1)
CEILING JOIST SPANS FOR COMMON LUMBER SPECIES
(Uninhabitable Attics Without Storage, Live Load = 10 pounds psf, L/Δ = 240)
CEILING JOIST SPACING (inches) | SPECIES AND GRADE | DEAD LOAD = 5 pounds per square foot | ||||
2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | |||
Maximum ceiling joist spans | ||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
12 | Douglas Fir-Larch | SS | 13-2 | 20-8 | 26-0 | 26-0 |
Douglas Fir-Larch | #1 | 12-8 | 19-11 | 26-0 | 26-0 | |
Douglas Fir-Larch | #2 | 12-5 | 19-6 | 25-8 | 26-0 | |
Douglas Fir-Larch | #3 | 10-10 | 15-10 | 20-1 | 24-6 | |
Hem-Fir | SS | 12-5 | 19-6 | 25-8 | 26-0 | |
Hem-Fir | #1 | 12-2 | 19-1 | 25-2 | 26-0 | |
Hem-Fir | #2 | 11-7 | 18-2 | 24-0 | 26-0 | |
Hem-Fir | #3 | 10-10 | 15-10 | 20-1 | 24-6 | |
Southern Pine | SS | 12-11 | 20-3 | 26-0 | 26-0 | |
Southern Pine | #1 | 12-8 | 19-11 | 26-0 | 26-0 | |
Southern Pine | #2 | 12-5 | 19-6 | 25-8 | 26-0 | |
Southern Pine | #3 | 11-6 | 17-0 | 21-8 | 25-7 | |
Spruce-Pine-Fir | SS | 12-2 | 19-1 | 25-2 | 26-0 | |
Spruce-Pine-Fir | #1 | 11-10 | 18-8 | 24-7 | 26-0 | |
Spruce-Pine-Fir | #2 | 11-10 | 18-8 | 24-7 | 26-0 | |
Spruce-Pine-Fir | #3 | 10-10 | 15-10 | 20-1 | 24-6 | |
16 | Douglas Fir-Larch | SS | 11-11 | 18-9 | 24-8 | 26-0 |
Douglas Fir-Larch | #1 | 11-6 | 18-1 | 23-10 | 26-0 | |
Douglas Fir-Larch | #2 | 11-3 | 17-8 | 23-0 | 26-0 | |
Douglas Fir-Larch | #3 | 9-5 | 13-9 | 17-5 | 21-3 | |
Hem-Fir | SS | 11-3 | 17-8 | 23-4 | 26-0 | |
Hem-Fir | #1 | 11-0 | 17-4 | 22-10 | 26-0 | |
Hem-Fir | #2 | 10-6 | 16-6 | 21-9 | 26-0 | |
Hem-Fir | #3 | 9-5 | 13-9 | 17-5 | 21-3 | |
Southern Pine | SS | 11-9 | 18-5 | 24-3 | 26-0 | |
Southern Pine | #1 | 11-6 | 18-1 | 23-1 | 26-0 | |
Southern Pine | #2 | 11-3 | 17-8 | 23-4 | 26-0 | |
Southern Pine | #3 | 10-0 | 14-9 | 18-9 | 22-2 | |
Spruce-Pine-Fir | SS | 11-0 | 17-4 | 22-10 | 26-0 | |
Spruce-Pine-Fir | #1 | 10-9 | 16-11 | 22-4 | 26-0 | |
Spruce-Pine-Fir | #2 | 10-9 | 16-11 | 22-4 | 26-0 | |
Spruce-Pine-Fir | #3 | 9-5 | 13-9 | 17-5 | 21-3 |
(continued)
TABLE 2308.10.2(1)—continued
CEILING JOIST SPANS FOR COMMON LUMBER SPECIES
(Uninhabitable Attics Without Storage, Live Load = 10 pounds psf, L/Δ = 240)
CEILING JOIST SPACING (inches) | SPECIES AND GRADE | DEAD LOAD = 5 pounds per square foot | ||||
2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | |||
Maximum ceiling joist spans | ||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
19.2 | Douglas Fir-Larch | SS | 11-3 | 17-8 | 23-3 | 26-0 |
Douglas Fir-Larch | #1 | 10-10 | 17-0 | 22-5 | 26-0 | |
Douglas Fir-Larch | #2 | 10-7 | 16-7 | 21-0 | 25-8 | |
Douglas Fir-Larch | #3 | 8-7 | 12-6 | 15-10 | 19-5 | |
Hem-Fir | SS | 10-7 | 16-8 | 21-11 | 26-0 | |
Hem-Fir | #1 | 10-4 | 16-4 | 21-6 | 26-0 | |
Hem-Fir | #2 | 9-11 | 15-7 | 20-6 | 25-3 | |
Hem-Fir | #3 | 8-7 | 12-6 | 15-10 | 19-5 | |
Southern Pine | SS | 11-0 | 17-4 | 22-10 | 26-0 | |
Southern Pine | #1 | 10-10 | 17-0 | 22-5 | 26-0 | |
Southern Pine | #2 | 10-7 | 16-8 | 21-11 | 26-0 | |
Southern Pine | #3 | 9-1 | 13-6 | 17-2 | 20-3 | |
Spruce-Pine-Fir | SS | 10-4 | 16-4 | 21-6 | 26-0 | |
Spruce-Pine-Fir | #1 | 10-2 | 15-11 | 21-0 | 25-8 | |
Spruce-Pine-Fir | #2 | 10-2 | 15-11 | 21-0 | 25-8 | |
Spruce-Pine-Fir | #3 | 8-7 | 12-6 | 15-10 | 19-5 | |
24 | Douglas Fir-Larch | SS | 10-5 | 16-4 | 21-7 | 26-0 |
Douglas Fir-Larch | #1 | 10-0 | 15-9 | 20-1 | 24-6 | |
Douglas Fir-Larch | #2 | 9-10 | 14-10 | 18-9 | 22-11 | |
Douglas Fir-Larch | #3 | 7-8 | 11-2 | 14-2 | 17-4 | |
Hem-Fir | SS | 9-10 | 15-6 | 20-5 | 26-0 | |
Hem-Fir | #1 | 9-8 | 15-2 | 19-7 | 23-11 | |
Hem-Fir | #2 | 9-2 | 14-5 | 18-6 | 22-7 | |
Hem-Fir | #3 | 7-8 | 11-2 | 14-2 | 17-4 | |
Southern Pine | SS | 10-3 | 16-1 | 21-2 | 26-0 | |
Southern Pine | #1 | 10-0 | 15-9 | 20-10 | 26-0 | |
Southern Pine | #2 | 9-10 | 15-6 | 20-1 | 23-11 | |
Southern Pine | #3 | 8-2 | 12-0 | 15-4 | 18-1 | |
Spruce-Pine-Fir | SS | 9-8 | 15-2 | 19-11 | 25-5 | |
Spruce-Pine-Fir | #1 | 9-5 | 14-9 | 18-9 | 22-11 | |
Spruce-Pine-Fir | #2 | 9-5 | 14-9 | 18-9 | 22-11 | |
Spruce-Pine-Fir | #3 | 7-8 | 11-2 | 14-2 | 17-4 |
TABLE 2308.10.2(2)
CEILING JOIST SPANS FOR COMMON LUMBER SPECIES
(Uninhabitable Attics With Limited Storage, Live Load = 20 pounds per square foot, L/Δ = 240)
CEILING JOIST SPACING (inches) | SPECIES AND GRADE | DEAD LOAD = 10 pounds per square foot | ||||
2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | |||
Maximum ceiling joist spans | ||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
12 | Douglas Fir-Larch | SS | 10-5 | 16-4 | 21-7 | 26-0 |
Douglas Fir-Larch | #1 | 10-0 | 15-9 | 20-1 | 24-6 | |
Douglas Fir-Larch | #2 | 9-10 | 14-10 | 18-9 | 22-11 | |
Douglas Fir-Larch | #3 | 7-8 | 11-2 | 14-2 | 17-4 | |
Hem-Fir | SS | 9-10 | 15-6 | 20-5 | 26-0 | |
Hem-Fir | #1 | 9-8 | 15-2 | 19-7 | 23-11 | |
Hem-Fir | #2 | 9-2 | 14-5 | 18-6 | 22-7 | |
Hem-Fir | #3 | 7-8 | 11-2 | 14-2 | 17-4 | |
Southern Pine | SS | 10-3 | 16-1 | 21-2 | 26-0 | |
Southern Pine | #1 | 10-0 | 15-9 | 20-10 | 26-0 | |
Southern Pine | #2 | 9-10 | 15-6 | 20-1 | 23-11 | |
Southern Pine | #3 | 8-2 | 12-0 | 15-4 | 18-1 | |
Spruce-Pine-Fir | SS | 9-8 | 15-2 | 19-11 | 25-5 | |
Spruce-Pine-Fir | #1 | 9-5 | 14-9 | 18-9 | 22-11 | |
Spruce-Pine-Fir | #2 | 9-5 | 14-9 | 18-9 | 22-11 | |
Spruce-Pine-Fir | #3 | 7-8 | 11-2 | 14-2 | 17-4 | |
16 | Douglas Fir-Larch | SS | 9-6 | 14-11 | 19-7 | 25-0 |
Douglas Fir-Larch | #1 | 9-1 | 13-9 | 17-5 | 21-3 | |
Douglas Fir-Larch | #2 | 8-9 | 12-10 | 16-3 | 19-10 | |
Douglas Fir-Larch | #3 | 6-8 | 9-8 | 12-4 | 15-0 | |
Hem-Fir | SS | 8-11 | 14-1 | 18-6 | 23-8 | |
Hem-Fir | #1 | 8-9 | 13-5 | 16-10 | 20-8 | |
Hem-Fir | #2 | 8-4 | 12-8 | 16-0 | 19-7 | |
Hem-Fir | #3 | 6-8 | 9-8 | 12-4 | 15-0 | |
Southern Pine | SS | 9-4 | 14-7 | 19-3 | 24-7 | |
Southern Pine | #1 | 9-1 | 14-4 | 18-11 | 23-1 | |
Southern Pine | #2 | 8-11 | 13-6 | 17-5 | 20-9 | |
Southern Pine | #3 | 7-1 | 10-5 | 13-3 | 15-8 | |
Spruce-Pine-Fir | SS | 8-9 | 13-9 | 18-1 | 23-1 | |
Spruce-Pine-Fir | #1 | 8-7 | 12-10 | 16-3 | 19-10 | |
Spruce-Pine-Fir | #2 | 8-7 | 12-10 | 16-3 | 19-10 | |
Spruce-Pine-Fir | #3 | 6-8 | 9-8 | 12-4 | 15-0 |
(continued)
TABLE 2308.10.2(2)—continued
CEILING JOIST SPANS FOR COMMON LUMBER SPECIES
(Uninhabitable Attics With Limited Storage, Live Load = 20 pounds per square foot, L/Δ = 240)
CEILING JOIST SPACING (inches) | SPECIES AND GRADE | DEAD LOAD = 10 pounds per square foot | ||||
2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | |||
Maximum ceiling joist spans | ||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
19.2 | Douglas Fir-Larch | SS | 8-11 | 14-0 | 18-5 | 23-4 |
Douglas Fir-Larch | #1 | 8-7 | 12-6 | 15-10 | 19-5 | |
Douglas Fir-Larch | #2 | 8-0 | 11-9 | 14-10 | 18-2 | |
Douglas Fir-Larch | #3 | 6-1 | 8-10 | 11-3 | 13-8 | |
Hem-Fir | SS | 8-5 | 13-3 | 17-5 | 22-3 | |
Hem-Fir | #1 | 8-3 | 12-3 | 15-6 | 18-11 | |
Hem-Fir | #2 | 7-10 | 11-7 | 14-8 | 17-10 | |
Hem-Fir | #3 | 6-1 | 8-10 | 11-3 | 13-8 | |
Southern Pine | SS | 8-9 | 13-9 | 18-1 | 23-1 | |
Southern Pine | #1 | 8-7 | 13-6 | 17-9 | 21-1 | |
Southern Pine | #2 | 8-5 | 12-3 | 15-10 | 18-11 | |
Southern Pine | #3 | 6-5 | 9-6 | 12-1 | 14-4 | |
Spruce-Pine-Fir | SS | 8-3 | 12-11 | 17-1 | 21-8 | |
Spruce-Pine-Fir | #1 | 8-0 | 11-9 | 14-10 | 18-2 | |
Spruce-Pine-Fir | #2 | 8-0 | 11-9 | 14-10 | 18-2 | |
Spruce-Pine-Fir | #3 | 6-1 | 8-10 | 11-3 | 13-8 | |
24 | Douglas Fir-Larch | SS | 8-3 | 13-0 | 17-1 | 20-11 |
Douglas Fir-Larch | #1 | 7-8 | 11-2 | 14-2 | 17-4 | |
Douglas Fir-Larch | #2 | 7-2 | 10-6 | 13-3 | 16-3 | |
Douglas Fir-Larch | #3 | 5-5 | 7-11 | 10-0 | 12-3 | |
Hem-Fir | SS | 7-10 | 12-3 | 16-2 | 20-6 | |
Hem-Fir | #1 | 7-6 | 10-11 | 13-10 | 16-11 | |
Hem-Fir | #2 | 7-1 | 10-4 | 13-1 | 16-0 | |
Hem-Fir | #3 | 5-5 | 7-11 | 10-0 | 12-3 | |
Southern Pine | SS | 8-1 | 12-9 | 16-10 | 21-6 | |
Southern Pine | #1 | 8-0 | 12-6 | 15-10 | 18-10 | |
Southern Pine | #2 | 7-8 | 11-0 | 14-2 | 16-11 | |
Southern Pine | #3 | 5-9 | 8-6 | 10-10 | 12-10 | |
Spruce-Pine-Fir | SS | 7-8 | 12-0 | 15-10 | 19-5 | |
Spruce-Pine-Fir | #1 | 7-2 | 10-6 | 13-3 | 16-3 | |
Spruce-Pine-Fir | #2 | 7-2 | 10-6 | 13-3 | 16-3 | |
Spruce-Pine-Fir | #3 | 5-5 | 7-11 | 10-0 | 12-3 |
Allowable spans for rafters shall be in accordance with Table 2308.10.3(1), 2308.10.3(2), 2308.10.3(3), 2308.10.3(4), 2308.10.3(5) or 2308.10.3(6). For other grades and species, refer to the AF&PA Span Tables for Joists and Rafters.
TABLE 2308.10.3(1)
RAFTER SPANS FOR COMMON LUMBER SPECIES
(Roof Live Load = 20 pounds per square foot, Ceiling Not Attached to Rafters, L/Δ = 180)
RAFTER SPACING (inches) | SPECIES AND GRADE | DEAD LOAD = 10 pounds per square foot | DEAD LOAD = 20 pounds per square foot | |||||||||
2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | 2 × 12 | 2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | 2 × 12 | |||
Maximum rafter spans | ||||||||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
12 | Douglas Fir-Larch | SS | 11-6 | 18-0 | 23-9 | 26-0 | 26-0 | 11-6 | 18-0 | 23-5 | 26-0 | 26-0 |
Douglas Fir-Larch | #1 | 11-1 | 17-4 | 22-5 | 26-0 | 26-0 | 10-6 | 15-4 | 19-5 | 23-9 | 26-0 | |
Douglas Fir-Larch | #2 | 10-10 | 16-7 | 21-0 | 25-8 | 26-0 | 9-10 | 14-4 | 18-2 | 22-3 | 25-9 | |
Douglas Fir-Larch | #3 | 8-7 | 12-6 | 15-10 | 19-5 | 22-6 | 7-5 | 10-10 | 13-9 | 16-9 | 19-6 | |
Hem-Fir | SS | 10-10 | 17-0 | 22-5 | 26-0 | 26-0 | 10-10 | 17-0 | 22-5 | 26-0 | 26-0 | |
Hem-Fir | #1 | 10-7 | 16-8 | 21-10 | 26-0 | 26-0 | 10-3 | 14-11 | 18-11 | 23-2 | 26-0 | |
Hem-Fir | #2 | 10-1 | 15-11 | 20-8 | 25-3 | 26-0 | 9-8 | 14-2 | 17-11 | 21-11 | 25-5 | |
Hem-Fir | #3 | 8-7 | 12-6 | 15-10 | 19-5 | 22-6 | 7-5 | 10-10 | 13-9 | 16-9 | 19-6 | |
Southern Pine | SS | 11-3 | 17-8 | 23-4 | 26-0 | 26-0 | 11-3 | 17-8 | 23-4 | 26-0 | 26-0 | |
Southern Pine | #1 | 11-1 | 17-4 | 22-11 | 26-0 | 26-0 | 11-1 | 17-3 | 21-9 | 25-10 | 26-0 | |
Southern Pine | #2 | 10-10 | 17-0 | 22-5 | 26-0 | 26-0 | 10-6 | 15-1 | 19-5 | 23-2 | 26-0 | |
Southern Pine | #3 | 9-1 | 13-6 | 17-2 | 20-3 | 24-1 | 7-11 | 11-8 | 14-10 | 17-6 | 20-11 | |
Spruce-Pine-Fir | SS | 10-7 | 16-8 | 21-11 | 26-0 | 26-0 | 10-7 | 16-8 | 21-9 | 26-0 | 26-0 | |
Spruce-Pine-Fir | #1 | 10-4 | 16-3 | 21-0 | 25-8 | 26-0 | 9-10 | 14-4 | 18-2 | 22-3 | 25-9 | |
Spruce-Pine-Fir | #2 | 10-4 | 16-3 | 21-0 | 25-8 | 26-0 | 9-10 | 14-4 | 18-2 | 22-3 | 25-9 | |
Spruce-Pine-Fir | #3 | 8-7 | 12-6 | 15-10 | 19-5 | 22-6 | 7-5 | 10-10 | 13-9 | 16-9 | 19-6 | |
16 | Douglas Fir-Larch | SS | 10-5 | 16-4 | 21-7 | 26-0 | 26-0 | 10-5 | 16-0 | 20-3 | 24-9 | 26-0 |
Douglas Fir-Larch | #1 | 10-0 | 15-4 | 19-5 | 23-9 | 26-0 | 9-1 | 13-3 | 16-10 | 20-7 | 23-10 | |
Douglas Fir-Larch | #2 | 9-10 | 14-4 | 18-2 | 22-3 | 25-9 | 8-6 | 12-5 | 15-9 | 19-3 | 22-4 | |
Douglas Fir-Larch | #3 | 7-5 | 10-10 | 13-9 | 16-9 | 19-6 | 6-5 | 9-5 | 11-11 | 14-6 | 16-10 | |
Hem-Fir | SS | 9-10 | 15-6 | 20-5 | 26-0 | 26-0 | 9-10 | 15-6 | 19-11 | 24-4 | 26-0 | |
Hem-Fir | #1 | 9-8 | 14-11 | 18-11 | 23-2 | 26-0 | 8-10 | 12-11 | 16-5 | 20-0 | 23-3 | |
Hem-Fir | #2 | 9-2 | 14-2 | 17-11 | 21-11 | 25-5 | 8-5 | 12-3 | 15-6 | 18-11 | 22-0 | |
Hem-Fir | #3 | 7-5 | 10-10 | 13-9 | 16-9 | 19-6 | 6-5 | 9-5 | 11-11 | 14-6 | 16-10 | |
Southern Pine | SS | 10-3 | 16-1 | 21-2 | 26-0 | 26-0 | 10-3 | 16-1 | 21-2 | 26-0 | 26-0 | |
Southern Pine | #1 | 10-0 | 15-9 | 20-10 | 25-10 | 26-0 | 10-0 | 15-0 | 18-10 | 22-4 | 26-0 | |
Southern Pine | #2 | 9-10 | 15-1 | 19-5 | 23-2 | 26-0 | 9-1 | 13-0 | 16-10 | 20-1 | 23-7 | |
Southern Pine | #3 | 7-11 | 11-8 | 14-10 | 17-6 | 20-11 | 6-10 | 10-1 | 12-10 | 15-2 | 18-1 | |
Spruce-Pine-Fir | SS | 9-8 | 15-2 | 19-11 | 25-5 | 26-0 | 9-8 | 14-10 | 18-10 | 23-0 | 26-0 | |
Spruce-Pine-Fir | #1 | 9-5 | 14-4 | 18-2 | 22-3 | 25-9 | 8-6 | 12-5 | 15-9 | 19-3 | 22-4 | |
Spruce-Pine-Fir | #2 | 9-5 | 14-4 | 18-2 | 22-3 | 25-9 | 8-6 | 12-5 | 15-9 | 19-3 | 22-4 | |
Spruce-Pine-Fir | #3 | 7-5 | 10-10 | 13-9 | 16-9 | 19-6 | 6-5 | 9-5 | 11-11 | 14-6 | 16-10 |
(continued)
TABLE 2308.10.3(1)—continued
RAFTER SPANS FOR COMMON LUMBER SPECIES
(Roof Live Load = 20 pounds per square foot, Ceiling Not Attached to Rafters, L/Δ = 180)
RAFTER SPACING (inches) | SPECIES AND GRADE | DEAD LOAD = 10 pounds per square foot | DEAD LOAD = 20 pounds per square foot | |||||||||
2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | 2 × 12 | 2 × 4 | 2 × 6 | 2 × 8 | 2 × 10 | 2 × 12 | |||
Maximum rafter spans | ||||||||||||
(ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | (ft. - in.) | |||
19.2 | Douglas Fir-Larch | SS | 9-10 | 15-5 | 20-4 | 25-11 | 26-0 | 9-10 | 14-7 | 18-6 | 22-7 | 26-0 |
Douglas Fir-Larch | #1 | 9-5 | 14-0 | 17-9 | 21-8 |