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2012 IRC Wall Bracing Provisions

CONTINUOUS SHEATHING METHODS END CONDITIONS

Module 6

2012 IRC Wall Bracing 2

Objectives

Upon completion of this module, you will be better able to:

• Discuss continuous sheathing methods include continuous sheathing - Wood Structural Panel, continuous sheathing at garage, continuous sheathing - portal frame.

• Explain method continuous sheathing - structural fiberboard

• Identify end conditions


Bracing: Panel Material - Continuous

2012 IBC Wall Bracing 4

Continuous Sheathing Bracing Methods:

CS-WSP - Continuously sheathed wood structural panel

CS-G - Continuously sheathed wood structural panel adjacent to garage openings

CS-PF - Continuously sheathed portal frame

CS-SFB - Continuously sheathed structural fiberboard

Table R602.10.4


Main Concepts – Allows for narrow BWP's

without hold-downs

– BWL's must be fully sheathed with wood structural panel or structural fiberboard sheathing (continuously sheathed)

2012 IBC Wall Bracing 5 R602.10.4.2, Table R602.10.5


2012 IBC Wall Bracing 6 R602.10.4.2 & R602.10.5

Sheathing Requirements: 1. Sheath full height areas including gable ends 2. Sheath above and below openings 3. Adjacent openings determine minimum BWP length

Too Narrow



Method CS-WSP

Continuous Sheathing with Wood Structural Panel • Area above and below openings fully sheathed including gable ends

• Min 3/8" wood structural panel sheathing

Method CS-SFB

Continuous Sheathing with Structural Fiberboard • Area above and below openings fully sheathed including gable ends

• Min 1/2" structural fiberboard sheathing

R602.10.4.2, Table R602.10.4


2012 IBC Wall Bracing - wind 8

Wall Bracing

Parameter

Continuously Sheathed

Wood Structural Panel

CS-WSP, CS-G, CS-PF

Continuously Sheathed

Structural Fiberboard

CS-SFB

Wind applicability < 110 mph ≤ 100 mph

Seismic applicability A - D2 A - C

Permitted wall heights 8' to 12' 8' to 12'

Corner return length

(both sides of corner)

24" Min.

(or hold downs at first BWP)

32" Min.

(or hold downs at first BWP)

Panel end distance 10' 10'

Table R602.10.4, Figure R602.10.7



Table R602.10.5

Method CS-WSP Full-height sheathed wall segments having a length equal or greater than

Table R602.10.5 are counted toward the total bracing length.

Braced wall panel minimum length is based on wall height and height of

the adjacent clear opening.

Too Narrow

a. Garage opening adjacent to method CS-G panel

shall have header. Max opening height includes

header height.

b. Max header height 10 feet, pony wall may be

used above header.


Method CS-WSP

Method

Adjacent

Clear

Opening

Height (ft.)

Wall Height (ft.)

8 9 10 11 12

CS-WSP

64 24 27 30 33 36

68 26 27 30 33 36

72 27 27 30 33 36

76 30 29 30 33 36

80 32 30 30 33 36

84 35 32 32 33 36

88 38 35 33 33 36

92 43 37 35 35 36

96 48 41 38 36 36

100 44 40 38 38

104 49 43 40 39

108 54 46 43 41

112 50 45 43

116 55 48 45

120 60 52 48

Method

Adjacent

Clear

Opening

Height

(ft.)

Wall Height (ft.)

8 9 10 11 12

CS-WSP

124 56 51

128 61 54

132 66 58

136 62

140 66

144 72

CS-G a 24 27 30 33 36 CS-PF <120 16 18 20 22b 24b

Table R602.10.5 Minimum Length of Braced Wall Panels (in)



36'

All panels less than 20′

apart edge to edge

< 20' < 20' < 20'

8'

R602.10.4.2 & Table R602.10.5

Too narrow to be counted

24" 108" 32" 24" 24" 24"

Method CS-WSP

12


Method CS-G Wood structural panel adjacent to garage opening – Full-height sheathed wall segments to either side of garage openings

– Roof covering dead loads of 3 psf or less (seismic requirement only)

– Applied to one wall line of garage only

– Panel length = bracing length

– 4:1 aspect ratio

12' Max

H/4 R602.10.4, Table R602.10.5

Garage Opening

2012 IBC Wall Bracing



4:1 Aspect Ratio (24" min.)

Garage only (roof covering limited to 3 psf in high seismic regions only).

Standard Header

Method CS-G



Method CS-PF Continuous portal frame Walls on either or both sides of openings in garage may have wall segment with a maximum 6:1 height-to-length ratio.

Garage Openin

g

H/6

10' max (12' max

with pony wall)

R602.10.6.4 Fully sheathed dwelling

Garage Opening

No hold-downs required OK on raised floor Top of header at 10' max

Top of wall at 12' max Panel length = bracing length


Extended Header

6:1 Aspect Ratio (16" min.)

Garage only, story above permitted.

R602.10.6.4, Table R602.10.5

Method CS-PF



Figure R602.10.6.4

Method

CS-PF

2012 IBC Wall Bracing



Methods PFH, PFG and CS-PF

MINIMUM WALL

STUD FRAMING

NOMINAL SIZE

AND GRADE

MAXIMUM

PONY WALL

HEIGHT

(feet)

MAXIMUM

TOTAL

WALL

HEIGHT

(feet)

MAXIMUM

OPENING

WIDTH

(feet)

BASIC WIND SPEED (mph)

85 90 100 85 90 100

Exposure B Exposure C

Tension strap capacity required (lbf)

2 × 4

No. 2 Grade

0 10 18 1000 1000 1000 1000 1000 1000

1 10

9 1000 1000 1000 1000 1000 1275

16 1000 1000 1750 1800 2325 3500

18 1000 1200 2100 2175 2725 DR

2 10

9 1000 1000 1025 1075 1550 2500

16 1525 2025 3125 3200 3900 DR

18 1875 2400 3575 3700 DR DR

2 12

9 1000 1200 2075 2125 2750 4000

16 2600 3200 DR DR DR DR

18 3175 3850 DR DR DR DR

Table R602.10.6.4: Tension Strap Capacity Required for Resisting Wind Pressures Perpendicular to Method PFH, PFG and CS-PF Braced Wall Panels



MINIMUM

WALL

STUD

FRAMING

NOMINAL SIZE

AND GRADE

MAXIMUM

PONY

WALL

HEIGHT

(feet)

MAXIMUM

TOTAL

WALL

HEIGHT

(feet)

MAXIMUM

OPENING

WIDTH

(feet)

BASIC WIND SPEED (mph)

85 90 100 85 90 100

Exposure B Exposure C

Tension strap capacity required (lbf)

2 × 4

No. 2 Grade 4 12

9 1775 2350 3500 3550 DR DR

16 4175 DR DR DR DR DR

2 × 6

Stud Grade

2 12

9 1000 1000 1325 1375 1750 2550

16 1650 2050 2925 3000 3550 DR

18 2025 2450 3425 3500 4100 DR

4 12

9 1125 1500 2225 2275 2775 3800

16 2650 3150 DR DR DR DR

18 3125 3675 DR DR DR DR

Table R602.10.6.4 cont.: Tension Strap Capacity Required for Resisting Wind Pressures Perpendicular to Method PFH, PFG and CS-PF Braced Wall Panels

Methods PFH, PFG and CS-PF cont.

4

CS-G CS-PF

2012 IBC Wall Bracing - wind 19




Method CS-SFB – Continuous Sheathing with Structural Fiberboard • Wall minimum length based on wall height and height of adjacent clear opening

• Maximum wall height = 12′

• Length requirements for braced wall panels in Table R602.10.5

– Same minimum bracing length requirements as CS-WSP

– Same aspect ratio (opening height limits) as CS-WSP

R602.10.5



4:1 4:1 6:1 ~2:1

0% to 65% H

0% to 65% H

0% to 65% H

18'

8'

R602.10.5.1

Too narrow to be counted

24" BWP

24" BWP

40" BWP

Method CS-SFB

18'

3:1 6:1 ~2.4:1 6:1

65% to

85% H

65% to

85% H

0% to

65%H 8'


2012 IBC Wall Bracing 22 R602.10.5.2

32" BWP

40" BWP

Method CS-SFB Too narrow to be counted

Bracing: End Conditions


End Conditions – 5 separate options WSP return panel and corner panel – 24″ minimum

SFB return panel and corner panel – 32″ minimum

R602.10.7

R602.10.7 End Conditions for Braced Wall Lines with Continuous Sheathing



End Condition 1

Braced wall panel at end of BWL

Return panel on perpendicular wall

R602.10.7



End Condition 2

Braced wall panel at end of BWL

800 lb hold-down in lieu of a return panel fastened to the corner stud

R602.10.7



End Condition 3

Minimum 48″ braced wall panel

No return required

R602.10.7



End Condition 4

Minimum 24 in. or 32 in. corner panel

Minimum 24 in. or 32 in. return panel on perpendicular wall

R602.10.7



End Condition 5 800 lb hold-down in

lieu of a braced wall panel at the end of the BWL,

Hold-down may be fastened to end of the first BWP.

Return panel on perpendicular wall or hold-down

R602.10.7



Minimum required CS-WSP = 24"

corner detail CS-SFB = 32"

Figure R602.10.7

18'

9' 84" 84"

32" BWP

32" BWP

24

" o

r 3

2"

Co

rne

r

24

" o

r 3

2"

Co

rne

r

36"

BWP

36"

BWP

Continuous Sheathing Corner Requirements



Gypsum

BWP Material or Infill

16d nail at 12" o.c.

Gypsum

16d nail at 12" o.c.

Table R602.3(1) Item 8

Table R602.3(1) Item 8 - Corner Stud Requirements

BWP Material or Infill

Summary

This module covered: – Continuous sheathing methods: – Continuous sheathing - Wood structural panel – Continuous sheathing at garage – Continuous sheathing - Portal frame

• All use OSB or plywood

• Continuous Sheathing - Structural Fiberboard – Uses structural fiberboard sheathing.

• End conditions for continuous sheathing along braced wall lines. – Required at the end of the braced wall

31 2012 IBC Wall Bracing

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© International Code Council 2014

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