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The table below lists the design code provisions from the AWC Special Design Provisions for Wind and Seismic (SDPWS) and the ASCE 7.applicable to shear wall design for the following materials
One column is for the design code provision, the other is for the implementation in Shearwalls; in most cases affecting design they are the same. However more choices for for the fastening spacing, stud spacing, and blocking may be included in Shearwalls based on practical considerations than are included in the SDPWS Table 4.3C for the purpose of providing shear capacities. In those cases capacities for configurations not listed in SDPWS are those for the next strongest configuration listed.
For some provisions, more detailed information is found in a table dedicated to the provision in another topic that is cross-referenced in this table.
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All Gypsum-based Materials |
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|---|---|---|---|---|---|---|
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Shearwalls |
SDPWS / ASCE 7 |
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Seismic Information |
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Allowable Design Categories |
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ASCE-7 Table 12.2-1, SDPWS 4.3.7.5-6 |
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35 feet or less |
Sets gypsum capacity to 0 for E, F |
Allows A, B, C, D |
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Greater than 35 feet |
Sets gypsum capacity to 0 for D, E, F |
Allows A, B, C |
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Response modification factor R |
Input in Site Dialog, Prompts to change upon load generation |
ASCE-7 Table 12.2-1, 12.8.1.1 |
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R -bearing walls |
Default 2.0 |
2.0 |
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R -building frames |
Default 2.5 |
2.5 |
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Deflection amplification factor Cd |
Input in Site Dialog, Prompts to change upon load generation |
ASCE-7 Table 12.2-1, 12.8.6 |
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Cd - bearing walls |
Default 2.0 |
2.0 |
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Cd - building frames |
Default 2.5 |
2.5 |
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Overstrength Factor W0* |
Cannot be overriden |
ASCE-7 Table 12.2-1, inc. note b; 12.10.1.1. |
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W0 - bearing walls, rigid diaphragms |
2.5 |
2.5 |
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W0 - building frames, rigid diaphragms |
2.5 |
2.5 |
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W0 - bearing walls, flexible diaphragms |
2.0 |
2.0 or 2.5 |
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W0 - building frames, flexible diaphragms |
2.0 |
2.0 or 2.5 |
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*for drag strut force from discontinuous shear lines above, only |
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Permissible Force Distribution Method |
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Refer to Shear Force Distribution Methods for more a description of these methods and how they are selected. |
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Reference |
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SDPWS 4.3.5.5.1 |
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Deflection-based distribution |
Allowed |
Allowed |
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Capacity-based distribution |
Contribution of gypsum ignored for seismic design |
Not allowed |
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Aspect Ratio |
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Aspect ratio = h/b, b = segment length, h = height, applies to wall segments or FTAO piers. For more details see Aspect Ratio Limits and Factors. |
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Maximum aspect ratio |
Aspect ratio is shown in Elevation view and in Wall and Shearline Output table |
4.3.3, Table 4.3.3, inc. Note 2 |
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Blocked |
2:1 |
2:1 |
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Unblocked |
1.5:1 |
1.5:1 |
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Shear Capacity Adjustments |
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ASD Reduction Factor |
Incorporated into design values |
SDPWS 4.1.4 |
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Wind design |
2.0 |
2.0 |
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Seismic design |
2.8 |
2.8 |
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Note for ASD Factor |
No note |
Note 1 referring to 4.1.4 |
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Specific gravity factor |
None |
None |
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Unblocked Factor |
None |
None |
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Aspect Ratio Factor |
None |
None |
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Perforated Wall Factor Co |
Gypsum only allowed in combination with wood structural panels on perforated walls; refer to Wood Structural Panel Provisions |
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Bending Resistance |
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Gypsum materials have no resistance to out-of-plane wind loads. If used on an exterior surface, no C&C loads should be applied to that building face. |
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Gypsum Board (GWB and GSB) |
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Shearwalls |
SDPWS |
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Combination of Sheathing Capacities |
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For more details, refer to Combination of Sheathing Capacities, |
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Reference |
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SDPWS 4.3.5.4, 4.3.5.4.2 Exception |
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Identical materials on both sides |
Add capacities |
Add capacities |
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Gypsum board on both sides, same blocking, but with different material details |
Vwc =Kmin Gac |
Vsc =Kmin Gac |
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Gypsum board on one side, plaster/lath on the other |
Twice weakest or strongest |
Twice weakest or strongest |
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Blocked gypsum board on one side, unblocked gypsum board on the other |
Twice weakest or strongest |
Twice weakest or strongest |
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Non-gypsum-based material on other side for seismic design |
Twice weakest or strongest |
Twice weakest or strongest |
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Wood structural panels or fiberboard on other side for wind design* |
Add capacities* |
Add capacities*
|
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Lumber siding or on other side, wind |
Twice weakest or strongest |
Twice weakest or strongest |
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Twice weakest or strongest: vn(c) = max ( 2 x min ( vn(1) ,vn(2)) , max( vn(1),vn(2) ) ) |
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*SDPWS refers only to gypsum wallboard (GWB), not gypsum sheathing board (GSB), but WoodWorks interprets the intention of the provision to include GSB |
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Combination of Apparent Stiffness Ga |
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For more details, refer to Combination of Sheathing Stiffness |
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Reference |
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SDPWS 4.3.5.4 |
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Identical materials on both sides |
Add stiffnesses |
Add stiffnesses |
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Gypsum board on both sides, same blocking, but with different material details |
Add stiffnesses |
Add stiffnesses |
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Blocked gypsum board on one side, unblocked gypsum board on the other |
Twice side with weakest capacity or side with strongest |
Twice side with weakest capacity or side with strongest |
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Gypsum board on one side, plaster/lath on the other |
Twice side with weakest capacity or side with strongest |
Twice side with weakest capacity or side with strongest capacity |
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Non-gypsum-based materials on the other side |
Twice side with weakest capacity or side with strongest |
Twice side with weakest capacity or side with strongest capacity |
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Twice weakest capacity or side with strongest cap: Ga(c) = max (2 x Ga (min ( vn(1) ,vn(2))) , Ga (max( vn(1),vn(2) ))) |
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Gypsum Wallboard (GWB) |
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Reference |
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Table 4.3C |
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Construction |
Shearwalls |
SDPWS |
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Thickness |
½”, 5/8” |
½” or 5/8” |
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No. of Plies – ½” |
1 |
1 only |
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No. of Plies – 5/8” |
1 or 2 |
1 or 2 |
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Blocking - ½” |
Either |
Either |
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Blocking - 1 ply 5/8” |
Either |
Either |
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Blocking - 2 ply 5/8” |
Blocked |
Blocked |
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|
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Stud Spacing |
Shearwalls spacing choices |
SDPWS Max spacing |
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½” , nails, unblocked |
12,16, 24” |
16” ,24” |
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½” , nails, blocked* |
12,16, 24" |
16” |
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5/8” ,nails, unblocked |
12,16, 24” |
24” |
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5/8”, nails, blocked* |
12,16, 24" |
16” |
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5/8”, 2 ply blocked |
12,16” |
16” |
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½”, Screws, 4"/12' spacing, blocked |
12,16",24" |
24" |
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½”, Screws, 4"/12' spacing, unblocked** |
12,16" |
not included |
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½”, Screws, 6"/12' spacing, blocked |
12,16" |
16" |
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½”, Screws, 6"/12' spacing, unblocked** |
12,16" |
not included |
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½”, Screws, 8"/12' spacing, blocked |
12,16" |
16" |
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½”, Screws, 8"/12' spacing, unblocked |
12,16" |
16" |
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½”, Screws, 4"/16" spacing, blocked |
12, 16" |
16" |
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5/8”, Screws, 8"/12', blocked or unblocked |
12,16", |
16" |
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* Although SDPWS max spacing is 16" for blocked sheathing, Shearwalls allows 24" using the capacity for unblocked shearwalls at 24" stud spacing |
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** Although SDPWS does not include this nail spacing for unblocked walls, Shearwalls allows 4" and 6" spacing with max 16" stud spacing using the capacity for 8" nail spacing |
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Fastener Types and Sizes |
Shearwalls selection |
SDPWS |
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Cooler nail (1/2" sheathing”) |
5d (0.086" x 1-5/8") |
5d (0.086" x 1-5/8") |
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Cooler nail (5/8" sheathing) |
6d (0.092" x 1-7/8") |
6d (0.0915" x 1-7/8") |
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Cooler nail – base ply |
6d |
6d (0.0915" x 1-7/8") |
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Cooler nail – face ply |
8d |
8d (0.0915" x 2-3/8") |
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Wallboard nail (1/2" sheathing) |
5d (0.086” x 1-5/8”) |
0.086” x 1-5/8” |
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Wallboard nail (5/8" sheathing”) |
6d (.0992” x 1-7/8”) |
0.0915” x 1-7/8” |
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Wallboard nail – base ply |
6d |
0.0915” x 1-7/8” |
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Wallboard nail – face ply |
8d |
0.113" x 2-3/8” |
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"Nail" (1/2 sheathing) |
0.120" x 1-1/2" |
0.120" x 1-1/2” |
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"Nail" (5/8 sheathing ) |
0.120" x 1-3/4" |
0.120" x 1-3/4” |
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"Nail" - base ply |
0.120" x 1-3/4" ... |
0.120" x 1.75” |
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"Nail" - face ply |
... 2-3/8" |
0.120" x 2-3/8" |
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Screw (1/2” sheathing) |
#6 1 ¼” |
#6 Type S or W 1¼” |
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Screw (5/8" sheathing”) |
#6 1 ¼” |
#6 Type S or W 1¼” |
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Screw – 2 ply |
Not included |
Not included |
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|
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Fastener Spacing |
Shearwalls choices |
SDWPWS max spacing |
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Edge nails – ½” |
4",7" |
4"or 7" |
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Field nails – ½” |
4",7" |
Doesn’t say |
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Edge nails – 5/8” |
4",7" |
4"or 7" |
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Field nails – 5/8" |
4",7" |
Doesn’t say |
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Edge nails – 2 ply 5/8” |
Base: 9, Face: 7 |
Base: 9, Face: 7 |
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Field nails – 2 ply 5/8” |
Not included |
Doesn't say |
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Edge screws – ½” unblocked |
4,6,8* |
8 |
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Edge screws – ½” blocked |
4,6,8 |
4,6,8 |
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Edge screws – 5/8” blocked or unblocked |
8 |
8 |
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Field screws – ½” unblocked |
12 |
12 |
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Field screws – 5/8” unblocked |
12 |
12 |
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Field screws – ½” blocked |
12,16 |
12,16 |
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** Although SDPWS does not include this nail spacing for unblocked walls, Shearwalls allows 4" and 6" spacing using the capacity for 8" nail spacing |
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|
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Shear Capacity |
Shearwalls |
SDPWS Table 4.3C |
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Thick. |
Fastener |
Spacing |
Studs |
Wind |
Seismic |
Divide by 2.0 (wind) 2.8 (seismic) |
½” |
nail |
7" |
24" |
75 |
53.6 |
150 |
½” |
nail |
4" |
24" |
110 |
78.6 |
220 |
½” |
nail |
7" |
16" unblk |
100 |
71.4 |
200 |
½” |
nail |
4" |
16" unblk |
125 |
89.3 |
250 |
½” |
nail |
7" |
16" block |
125 |
89.3 |
250 |
½” |
nail |
4" |
16" block |
150 |
107.1 |
300 |
5/8" |
nail |
7" |
24" or unblock |
115 |
82.1 |
230 |
5/8" |
nail |
4" |
24" or unblock |
145 |
103.6 |
290 |
5/8” |
nail |
7" |
16' block |
145 |
103.6 |
290 |
5/8” |
nail |
4" |
16" block |
175 |
125 |
350 |
5/8” 2-ply |
nail |
7" / 9" |
16" block |
250 |
178.6 |
500 |
½” |
screw |
8"/12" |
16" unblk |
60 |
42.9 |
120 |
½” |
screw |
8"/12" |
16" block |
70 |
50 |
140 |
½” |
screw |
6"/12" |
16" block |
90 |
64.3 |
180 |
½” |
screw |
4"/12" |
24" block |
155 |
110.7 |
310 |
½” |
screw |
4" /16" |
16" block |
160 |
114.3 |
320 |
5/8” |
screw |
8"/12" |
16" unblk |
70 |
50 |
140 |
5/8” |
screw |
8"/12" |
16" block |
90 |
64.3 |
180 |
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Gypsum Sheathing Board (GSB) |
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Reference |
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Table 4.3C |
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|
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Sheathing Sizes |
Shearwalls selections |
SDPWS Table |
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Thickness |
½” or 5/8” |
½” or 5/8” |
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Sizes – 1/2" thickness |
2' x 8'; 4' x 8' |
2' x 8'; 4'' wide |
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Sizes – 5/8" thickness |
4' x 8' |
4' wide' |
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|
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Blocking |
Shearwalls selections |
SDPWS |
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½” x 2’ |
Blocked or Unblocked |
Unblocked |
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½” x 4’ |
Blocked or Unblocked |
Blocked or Unblocked |
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5/8" x 4' |
Blocked |
Blocked |
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|
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Stud Spacing |
Shearwalls selections |
SDPWS Maximum |
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½” x 2’ |
12,16" |
|
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½ x 4’ blocked |
12,16,24” |
24” |
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½ x 4’ unblocked |
12,16” |
16” |
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5/8" x 4' |
12,16” |
16" |
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|
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Fastener Types |
Shearwalls |
SDPWS |
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Galvanized nail (1/2" sheathing”) |
0.120” x 1-3/4" |
0.120” x 1¾” |
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"Nail" (5/8” sheathing) |
0.120” x 1-3/4" |
0.120” x 1¾” |
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Cooler nail (5/8” sheathing ) |
6d (.092" x 1-7/8”) |
6d galvanized, .092” x 1-7/8” |
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Wallboard Nail (5/8” sheathing) |
6d (.092" x 1-7/8”) |
0.0915" x 1-7/8” |
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|
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Fastener Spacing |
Shearwalls selections |
SDPWS Maximum |
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Edge – ½ x 2’ |
4 |
4 |
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Edge – ½ x 4’ , blocked |
4 |
4 |
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Edge – ½ x 4’ unblocked |
4, 7* |
7 |
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Edge – 5/8 x 4’ |
4 |
4 |
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Field – ½ x 2’ |
4 |
Doesn't say |
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Field – ½ x 4’ blocked |
4 |
Doesn’t say |
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Field – ½ x 4’ unblocked |
7 |
Doesn’t say |
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Field – 5/8 x 4’ |
7 |
7 |
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* Shearwalls permits 4" unblocked spacing and uses 7" capacity in that case. |
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Shear Capacity |
Shearwalls |
SDPWS |
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|
Wind |
Seismic |
Divide by 2.0 (wind) 2.8 (seismic) |
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½” x 2’ |
75 |
53.6 |
150 |
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½” x 4’ blocked |
175 |
125 |
350 |
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½” x 4’ unblocked |
100 |
71.4 |
200 |
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5/8” x 4’ |
200 |
142.9 |
400 |
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|
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Lath and Plaster |
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|
Shearwalls |
SDPWS |
||||
Combination of Sheathing Capacities |
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For more details, refer to Combination of Sheathing Capacities, |
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Reference |
|
SDPWS 4.3.5.4 |
||||
Identical materials on both sides |
Add capacities |
Add capacities |
||||
Plaster/lath on both sides but with different material details |
Vwc =Kmin Gac |
Vsc =Kmin Gac |
||||
Gypsum board on one side, plaster/lath on the other |
Twice weakest or strongest |
Twice weakest or strongest |
||||
Non-gypsum-based material on other side |
Twice weakest or strongest |
Twice weakest or strongest |
||||
Wood structural panels or fiberboard on other side for wind design* |
Add capacities* |
Add capacities*
|
||||
Lumber siding or on other side, wind |
Twice weakest or strongest |
Twice weakest or strongest |
||||
|
|
|
||||
Combination of Apparent Stiffness Ga |
||||||
For more details, refer to Combination of Sheathing Stiffness |
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Reference |
|
SDPWS 4.3.5.4 |
||||
Identical materials on both sides |
Add stiffnesses |
Add stiffnesses |
||||
Plaster/lath on both sides but with different material details |
Add stiffnesses |
Add stiffnesses |
||||
Gypsum board on one side, plaster/lath on the other |
Twice side with weakest capacity or side with strongest |
Twice side with weakest capacity or side with strongest capacity |
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Non-gypsum-based materials on the other side |
Twice side with weakest capacity or side with strongest |
Twice side with weakest capacity or side with strongest capacity |
||||
Twice weakest capacity or side with strongest cap: Ga(c) = max (2 x Ga (min ( vn(1) ,vn(2))) , Ga (max( vn(1),vn(2) ))) Divide by 2.0 (wind) 2.8 (seismic) |
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|
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Wire Lath and Plaster |
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Reference |
|
Table 4.3C |
||||
Construction |
Shearwalls |
SDPWS |
||||
Thickness |
7/8” |
7/8” |
||||
Blocking |
Disabled and unblocked |
Unblocked |
||||
Stud Spacing |
12”,16” |
16” |
||||
|
||||||
Fastener Types |
||||||
Nail |
0.120” x 1-1/2"” |
0.120” x 1-1/2"” |
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|
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Fastener spacing |
||||||
Edge nail spacing |
6” |
6” |
||||
Field nail spacing |
6” |
Doesn’t say (not applicable) |
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|
||||||
Shear Resistance |
Shearwalls |
SDPWS |
||||
|
Wind |
Seismic |
Divide by 2.0 (wind) 2.8 (seismic) |
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|
180 |
128.6 |
360 |
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|
||||||
Gypsum Lath and Plaster |
||||||
Important Note - Shearwalls does not implement Gypsum lath with vertical joints staggered |
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Reference |
|
Table 4.3C |
||||
Construction |
|
|
||||
Thickness |
7/8” |
7/8” |
||||
Blocking |
Disabled and unblocked |
Unblocked |
||||
Stud Spacing |
12,16” |
16” |
||||
|
||||||
Fastener Types |
|
|
||||
GWB blued nail |
0.092” x 1-1/8” |
0.092” x 1-1/8” |
||||
"Nail" |
0.120" x 1-1/4" |
0.120" x 1-1/4" |
||||
|
||||||
Fastener spacing |
|
|
||||
Edge nail spacing |
5” |
5” |
||||
Field nail spacing |
5” |
Doesn’t say (not applicable) |
||||
|
||||||
Shear Resistance |
Shearwalls |
SDPWS |
||||
|
Wind |
Seismic |
Divide by 2.0 (wind) 2.8 (seismic) |
|||
Vertical Joints Staggered |
180 |
128.6 |
360 |
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Vertical Joints not staggered |
100 |
71.4 |
200 |
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