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SECTION 2304 GENERAL CONSTRUCTION REQUIREMENTS

2304.1 General.
The provisions of this section apply to design methods specified in Section 2301.2.

2304.2 Size of structural members.
Computations to determine the required sizes of members shall be based on the net dimensions (actual sizes) and not nominal sizes.

2304.3 Wall framing.
The framing of exterior and interior walls shall be in accordance with the provisions specified in Section 2308 unless a specific design is furnished.

2304.3.1 Bottom plates. Studs shall have full bearing on a 2-inch-thick (actual 11/2-inch, 38 mm) or larger plate or sill having a width at least equal to the width of the studs.
2304.3.2 Framing over openings. 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.
2304.3.3 Shrinkage. 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 also 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.
2304.3.4 Additional requirements. [DSA-SS, DSA-SS/CC and OSHPD 1, 2 & 4] The following additional requirements apply:
1. Engineering analysis shall be furnished that demonstrates compliance of wall framing elements and connections with Section 2301.2, Item 1 or 2.
2. Construction documents shall include detailing of sill plate anchorage to supporting masonry or concrete for all exterior and interior bearing, nonbearing and shear walls. Unless specifically designed in accordance with item 1 above, sills under exterior walls, bearing walls and shear walls shall be bolted to masonry or concrete with 5/8 inch diameter by 12 inch (16 mm by 305 mm) bolts spaced not more than four (4) feet (1219 mm) on center, with a minimum of two (2) bolts for each piece of sill plate. Anchor bolts shall have a 4 inch (1016 mm) minimum and a 12 inch (304.8 mm) maximum clearance to the end of the sill plate, and 7 inch (177.8 mm) minimum embedment into concrete or masonry.

Unless specifically designed in accordance with Item 1 above, sill plates under nonbearing interior partitions on concrete floor slabs shall be anchored at not more than four (4) feet (1219 mm) on center to resist a minimum allowable stress shear of 100 pounds per linear foot (1.4 kN/m) acting either parallel or perpendicular to the wall.
3. Construction documents shall include detailing and limitations for notches and bored holes in wall studs, plates and sills.
2304.4 Floor and roof framing. 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.

2304.4.1 Additional requirements. [DSA-SS, DSA-SS/ CC and OSHPD 1, 2 & 4] The following additional requirements apply:
1. Engineering analysis shall be furnished that demonstrates compliance of floor, roof and ceiling framing elements and connections with Section 2301.2, Items 1 or 2.
2. Construction documents shall include detailing and limitations for notches and bored holes in floor and roof framing members.
2304.5 Framing around flues and chimneys. Combustible framing shall be a minimum of 2 inches (51 mm), but shall not be less than the distance specified in Sections 2111 and 2113 and the California Mechanical Code, from flues, chimneys and fireplaces, and 6 inches (152 mm) away from flue openings.

2304.6 Wall sheathing.
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 Tables 2306.5 and 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


For SI: 1 inch = 25.4 mm.


2304.6.1 Wood structural panel sheathing. Where wood structural panel sheathing is used as the exposed finish on the exterior of outside 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), an importance factor (I) of 1.0 and a topographic factor (Kz t) of 1.0.

Exception: [DSA-SS and OSHPD 1 & 4]
Wind pressure shall be calculated in accordance with Section 1609A.

TABLE 2304.6.1 MAXIMUM BASIC WIND SPEED (mph) (3-SECOND GUST) 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 WIND SPEED (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.

a. Panel strength axis shall be parallel or perpendicular to supports. Three-ply plywood sheathing with studs spaced more than 16 inches on center shall be applied with panel strength axis perpendicular to supports.


b. The table is based on wind pressures acting toward and away from building surfaces in accordance with Section 6.4.2.2 of ASCE 7. Lateral requirements shall be in accordance with Section 2305 or 2308.


c. Wood structural panels with span ratings of wall-16 or wall-24 shall be permitted as an alternative to panels with a 24/0 span rating. Plywood siding rated 16 o.c. or 24 o.c. shall be permitted as an alternative to panels with a 24/16 span rating. Wall-16 and plywood siding 16 o.c. shall be used with studs spaced a maximum of 16 inches o.c.
2304.6.2 Interior paneling. Softwood wood structural panels used for interior paneling shall conform to the provisions of Chapter 8 and shall be installed in accordance with Table 2304.9.1. Panels shall comply with DOC PS 1 or PS 2. Prefinished hardboard paneling shall meet the requirements of CPA/ANSI A135.5. Hardwood plywood shall conform to HPVA HP-1.
2304.7 Floor and roof sheathing.

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


For SI: 1 inch = 25.4 mm.

a. Installation details shall conform to Sections 2304.7.1 and 2304.7.2 for floor and roof sheathing, respectively.


b. Floor or roof sheathing conforming with this table shall be deemed to meet the design criteria of Section 2304.7.


c. Maximum 19-percent moisture content.


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


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

a. Applies to panels 24 inches or wider.


b. Floor and roof sheathing conforming with this table shall be deemed to meet the design criteria of Section 2304.7.


c. Uniform load deflection limitations 1/180 of span under live load plus dead load, 1/240 under live load only.


d. 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.


e. Allowable load at maximum span.


f. 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.


g. For 1/2-inch panel, maximum span shall be 24 inches.


h. Span is permitted to be 24 inches on center where 3/4-inch wood strip flooring is installed at right angles to joist.


i. 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 2304.7(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.


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

a. 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.


b. Floor panels conforming with this table shall be deemed to meet the design criteria of Section 2304.7.


c. Applicable to all grades of sanded exterior-type plywood. See DOC PS 1 for plywood species groups.


d. Applicable to Underlayment grade, C-C (Plugged) plywood, and Single Floor grade wood structural panels.


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


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

a. Roof sheathing conforming with this table shall be deemed to meet the design criteria of Section 2304.7.


b. 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.


c. For composite and four-ply plywood structural panel, load shall be reduced by 15 pounds per square foot.


2304.7.1 Structural floor sheathing. Structural floor sheathing shall be designed in accordance with the general provisions of this code and the special provisions in this section.

Floor sheathing conforming to the provisions of Table 2304.7(1), 2304.7(2), 2304.7(3) or 2304.7(4) shall be deemed to meet the requirements of this section.
2304.7.2 Structural roof sheathing. 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 2304.7(1), 2304.7(2), 2304.7(3) or 2304.7(5) shall be deemed to meet the requirements of this section. Wood structural panel roof sheathing shall be bonded by exterior glue.
2304.8 Lumber decking.

2304.8.1 General. Lumber decking shall be designed and installed in accordance with the general provisions of this code and Section 2304.8. Each piece shall be square end trimmed. When random lengths are furnished, each piece shall be square end trimmed across the face so that at least 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.
2304.8.2 Layup patterns. Lumber decking is permitted to be laid up following one of five standard patterns as defined in Sections 2304.8.2.1 through 2304.8.2.5. Other patterns are permitted to be used provided they are substantiated through engineering analysis.
2304.8.2.1 Simple span pattern. All pieces shall be supported on their ends (i.e., by two supports).
2304.8.2.2 Two-span continuous pattern. All pieces shall be supported by three supports, and all end joints shall occur in line on alternating supports. Supporting members shall be designed to accommodate the load redistribution caused by this pattern.
2304.8.2.3 Combination simple and two-span continuous pattern. Courses in end spans shall be alternating simple-span pattern and two-span continuous pattern. End joints shall be staggered in adjacent courses and shall bear on supports.
2304.8.2.4 Cantilevered pieces intermixed pattern. The decking shall extend across a minimum of 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 at least one support.
2304.8.2.5 Controlled random pattern. 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.

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. There shall be no end joints in the decking between the cantilevered end of the decking and the centerline of the first adjacent interior span.
2304.8.3 Mechanically laminated decking.
2304.8.3.1 General. Mechanically laminated decking consists of square-edged dimension lumber laminations set on edge and nailed to the adjacent pieces and to the supports.
2304.8.3.2 Nailing. 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.

Laminations shall be toenailed to supports with 20d or larger common nails. Where the supports are 48 inches (1219 mm) o.c. or less, alternate laminations shall be toenailed to alternate supports; where supports are spaced more than 48 inches (1219 mm) o.c., alternate laminations shall be toenailed to every support.
2304.8.3.3 Controlled random pattern. There shall be a minimum distance of 24 inches (610 mm) between end joints in adjacent courses. The pieces in the first and second courses shall bear on at least two supports with end joints in these two courses occurring on alternate supports. A maximum of seven intervening courses shall be permitted before this pattern is repeated.
2304.8.4 Two-inch sawn tongue-and-groove decking.
2304.8.4.1 General. Two-inch (51 mm) decking shall have a maximum moisture content of 15 percent. Decking shall be machined with a single tongue-and-groove pattern. Each decking piece shall be nailed to each support.
2304.8.4.2 Nailing. Each piece of decking shall be toenailed at each support with one 16d common nail through the tongue and face-nailed with one 16d common nail.
2304.8.4.3 Controlled random pattern. There shall be a minimum distance of 24 inches (610 mm) between end joints in adjacent courses. The pieces in the first and second courses shall bear on at least two supports with end joints in these two courses occurring on alternate supports. A maximum of seven intervening courses shall be permitted before this pattern is repeated.
2304.8.5 Three- and 4-inch sawn tongue-and-groove decking.
2304.8.5.1 General. Three-inch (76 mm) and 4-inch (102 mm) decking shall have a maximum moisture content of 19 percent. Decking shall be machined with a double tongue-and-groove pattern. Decking pieces shall be interconnected and nailed to the supports.
2304.8.5.2 Nailing. Each piece shall be toenailed at each support with one 40d common nail and face-nailed with one 60d common nail. Courses shall be spiked to each other with 8-inch (203 mm) spikes at maximum intervals of 30 inches (762 mm) through predrilled edge holes penetrating to a depth of approximately 4 inches (102 mm). One spike shall be installed at a distance not exceeding 10 inches (254 mm) from the end of each piece.
2304.8.5.3 Controlled random pattern. 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 the adjacent pieces in the same course continue over the support for at least 24 inches (610 mm). This condition shall not occur more than once in every six courses in each interior bay.
2304.9 Connections and fasteners.

2304.9.1 Fastener requirements. 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, face nail
Table 2308.10.4.1
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, face nail
Table 2308.10.4.1
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″) face nail
2 - 3″ × 0.131″ nails
3 - 3″14 gage staples
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 staggered 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 8ddor 6de
23/8″ × 0.113″ nailp
2″16 gagep
7/8″ to 1″ 8dc
11/8″ to 11/4 10ddor 8de
Single floor (combination subfloor-underlayment to framing) 3/4″ and less 6de
7/8″ to 1″ 8de
11/8″ to 11/4 10ddor 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


For SI: 1 inch = 25.4 mm.

a. Common or box nails are permitted to be used except where otherwise stated.


b. Nails spaced at 6 inches on center at edges, 12 inches at intermediate supports except 6 inches at 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.


c. Common or deformed shank (6d - 2″ × 0.113″; 8d - 21/2″ × 0.131″; 10d - 3″ × 0.148″).


d. Common (6d - 2″ × 0.113″; 8d - 21/2″ × 0.131″; 10d - 3″ × 0.148″).


e. Deformed shank (6d - 2″ × 0.113″; 8d - 21/2″ × 0.131″; 10d - 3″ × 0.148″).


f. Corrosion-resistant siding (6d - 17/8″ × 0.106″; 8d - 23/8″ × 0.128″) or casing (6d - 2″ × 0.099″; 8d - 21/2″ × 0.113″) nail.


g. Fasteners spaced 3 inches on center at exterior edges and 6 inches on center at intermediate supports, when used as structural sheathing. Spacing shall be 6 inches on center on the edges and 12 inches on center at intermediate supports for nonstructural applications.


h. Corrosion-resistant roofing nails with 7/16-inch-diameter head and 11/2-inch length for 1/2-inch sheathing and 13/4-inch length for 25/32-inch sheathing.


i. Corrosion-resistant staples with nominal 7/16-inch crown or 1-inch crown and 11/4-inch length for 1/2-inch sheathing and 11/2-inch length for 25/32-inch sheathing. Panel supports at 16 inches (20 inches if strength axis in the long direction of the panel, unless otherwise marked).


j. Casing (11/2″ × 0.080″) or finish (11/2″ × 0.072″) nails spaced 6 inches on panel edges, 12 inches at intermediate supports.


k. Panel supports at 24 inches. Casing or finish nails spaced 6 inches on panel edges, 12 inches at intermediate supports.


l. For roof sheathing applications, 8d nails (21/2″ × 0.113″) are the minimum required for wood structural panels.


m. Staples shall have a minimum crown width of 7/16 inch.


n. For roof sheathing applications, fasteners spaced 4 inches on center at edges, 8 inches at intermediate supports.


o. Fasteners spaced 4 inches on center at edges, 8 inches at intermediate supports for subfloor and wall sheathing and 3 inches on center at edges, 6 inches at intermediate supports for roof sheathing.


p. Fasteners spaced 4 inches on center at edges, 8 inches at intermediate supports.
2304.9.1.1 Additional requirements. [DSA-SS and OSHPD 1, 2 & 4] Fasteners used for the attachment of exterior wall coverings shall be of hot-dipped zinc- coated galvanized steel, mechanically deposited zinc-coated steel, stainless steel, silicon bronze or copper. The coating weights for hot-dipped zinc-coated fasteners shall be in accordance with ASTM A 153. The coating weights for mechanically deposited zinc-coated fasteners shall be in accordance with ASTM B 695, Class 55 minimum.
2304.9.2 Sheathing fasteners. Sheathing nails or other approved sheathing connectors shall be driven so that their head or crown is flush with the surface of the sheathing.
2304.9.3 Joist hangers and framing anchors. 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 Section 1716.1.
2304.9.4 Other fasteners. Clips, staples, glues and other approved methods of fastening are permitted where approved.
2304.9.5 Fasteners and connectors in contact with preservative-treated and fire-retardant-treated wood. Fasteners and connectors in contact with preservative-treated and fire-retardant-treated wood shall be in accordance with Sections 2304.9.5.1 through 2304.9.5.4. The coating weights for zinc-coated fasteners shall be in accordance with ASTM A 153.
2304.9.5.1 Fasteners and connectors for preservative-treated wood. Fasteners 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.

Exception:
Plain carbon steel fasteners in SBX/DOT and zinc borate preservative-treated wood in an interior, dry environment shall be permitted.
2304.9.5.2 Fastenings for wood foundations. Fastenings for wood foundations shall be as required in AF&PA PWF.
2304.9.5.3 Fasteners for fire-retardant-treated wood used in exterior applications or wet or damp locations. Fasteners 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. 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.
2304.9.5.4 Fasteners for fire-retardant-treated wood used in interior applications. Fasteners 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 2304.9.5.3 shall apply.
2304.9.6 Load path. Where wall framing members are not continuous from foundation sill to 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 0.040 inch (1.01 mm) nominal thickness.
2304.9.7 Framing requirements. 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.
2304.10 Heavy timber construction.

2304.10.1 Columns. Columns shall be continuous or superimposed throughout all stories by means of reinforced concrete or metal caps with brackets, or shall be connected by properly designed steel or iron caps, with pintles and base plates, or by timber splice plates affixed to the columns by metal connectors housed within the contact faces, or by other approved methods.
2304.10.1.1 Column connections. Girders and beams 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.
2304.10.2 Floor framing. 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 ledgers or blocks securely fastened to the sides of the girders, or they shall be supported by an approved metal hanger into which the ends of the beams shall be closely fitted.
2304.10.3 Roof framing. Every roof girder and at least every alternate roof beam shall be anchored to its supporting member; and every monitor and every sawtooth construction shall be anchored to the main roof construction. Such anchors shall consist of steel or iron bolts of sufficient strength to resist vertical uplift of the roof.
2304.10.4 Floor decks. Floor decks and covering shall not extend closer than 1/2 inch (12.7 mm) to walls. Such 1/2-inch (12.7 mm) spaces shall be covered by a molding fastened to the wall either above or below the floor and arranged such that the molding will not obstruct the expansion or contraction movements of the floor. Corbeling of masonry walls under floors is permitted in place of such molding.
2304.10.5 Roof decks. Where supported by a wall, roof decks shall be anchored to walls to resist uplift forces determined in accordance with Chapter 16. Such anchors shall consist of steel or iron bolts of sufficient strength to resist vertical uplift of the roof.
2304.11 Protection against decay and termites.

2304.11.1 General. Where required by this section, protection from decay and termites shall be provided by the use of naturally durable or preservative-treated wood.
2304.11.2 Wood used above ground. Wood used above ground in the locations specified in Sections 2304.11.2.1 through 2304.11.2.7, 2304.11.3 and 2304.11.5 shall be naturally durable wood or preservative-treated wood using water-borne preservatives, in accordance with AWPA U1 (Commodity Specifications A or F) for above-ground use.
2304.11.2.1 Joists, girders and subfloor. Where wood joists or the bottom of a wood structural floor without joists are closer than 18 inches (457 mm), or wood girders 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, the floor construction (including posts, girders, joists and subfloor) shall be of naturally durable or preservative-treated wood.
2304.11.2.1.1 [SPCB] There shall be a clearance of at least 18 inches (457 mm) between the underside of wood floor joists and the finished surface of the ground, and at least 12 inches (305 mm) between the underside of any other wood horizontal framing member and the finished surface of the ground. The ground underneath floor joists shall be leveled or smoothed off so as to maintain a reasonably even surface.

Exception:
For purposes of structural pest control inspection, a minimum of 12 inches (305 mm) of clearance under-floor joists shall be considered adequate except that such clearance shall not be necessary where the subarea soil is of such a nature as to prevent excavation or where excavation would create a hazard from shifting soil or other causes.
2304.11.2.2 Wood supported by exterior foundation walls. Wood framing members, including wood sheathing, that rest on exterior foundation walls and are less than 8 inches (203 mm) from exposed earth shall be of naturally durable or preservative-treated wood.

Exception: [DSA-SS and OSHPD 1, 2 & 4]
At exterior walls where the earth is paved with an asphalt or concrete slab at least 18 inches (457 mm) wide and draining away from the building, the bottom of sills are permitted to be 6 inches (152 mm) above the top of such slab. Other equivalent means of termite and decay protection may be accepted by the enforcement agency.
2304.11.2.3 Exterior walls below grade. Wood framing members and furring strips attached directly to the interior of exterior masonry or concrete walls below grade shall be of approved naturally durable or preservative-treated wood.
2304.11.2.4 Sleepers and sills. 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.
2304.11.2.4.1 Additional requirements. [DSA-SS and OSHPD 1, 2 & 4] Stud walls or partitions at shower or toilet rooms with more than two fixtures, and stud walls adjacent to unroofed paved areas shall rest on a concrete curb extending at least 6 inches (152 mm) above finished floor or pavement level.
2304.11.2.5 Girder ends. The ends of wood girders entering exterior masonry or concrete walls shall be provided with a 1/2-inch (12.7 mm) air space on top, sides and end, unless naturally durable or preservative-treated wood is used.
2304.11.2.6 Wood siding. Clearance between wood siding and earth on the exterior of a building shall not be 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.
2304.11.2.7 Posts or columns. 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.

Exceptions:
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.
2304.11.2.8 Separate wood framing. [SPCB] Correct the conditions in frame and stucco walls and similar appurtenant construction so that the wood framing is separate from the main structure by a complete concrete or masonry plug with no voids that will allow infestations to enter the structure from the wall. If there is no plug, the foundation shall be 2 inches (51 mm) or more above the grade levels and at least as high as the adjoining slabs or 4-inch (102 mm) concrete barrier seat off installed.
2304.11.3 Laminated timbers. The portions of glued-laminated timbers that form the structural supports of a building or other structure and are exposed to weather and not fully protected from moisture by a roof, eave or similar covering shall be pressure treated with preservative or be manufactured from naturally durable or preservative-treated wood.
2304.11.4 Wood in contact with the ground or fresh water. 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.

Exception:
Untreated wood is permitted where such wood is continuously and entirely below the ground- water level or submerged in fresh water.
2304.11.4.1 Posts or columns. Posts and columns supporting permanent structures that are embedded in concrete that is in direct contact with the earth, embedded in concrete that is exposed to the weather or in direct contact with the earth shall be of preservative-treated wood.
2304.11.4.2 Wood structural members. 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.
2304.11.5 Supporting member for permanent appurtenances. 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:
When a building is 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.
2304.11.6 Termite protection. In geographical areas where hazard of termite damage is known to be very heavy, wood floor framing shall be of naturally durable species (termite resistant) or preservative treated in accordance with AWPA U1 for the species, product preservative and end use or provided with approved methods of termite protection.
2304.11.7 Wood used in retaining walls and cribs. Wood installed in retaining or crib walls shall be preservative treated in accordance with AWPA U1 (Commodity Specifications A or F) for soil and fresh water use.
2304.11.8 Attic ventilation. For attic ventilation, see Section 1203.2.
2304.11.9 Under-floor ventilation (crawl space). For under-floor ventilation (crawl space), see Section 1203.3.
2304.11.10 Earth fills. [SPCB] Separate the earth fills such as under porches or paving from all woodwork by concrete, masonry, good quality cement plaster or other material approved by local building codes. Chemical treatment of earth fills is considered adequate if the foundation adjoining the fill meets standards of the current building codes.
2304.12 Long-term loading. Wood members supporting concrete, masonry or similar materials shall be checked for the effects of long-term loading using the provisions of the 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.

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.