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Important Note – These are descriptions to changes implemented in WoodWorks Shearwalls for version 9 and may not reflect current behavior.
Unless otherwise noted, the changes to the fastener specifications in the program are not due to changes in the SDPWS from 2005 to 2008, rather to update the program to the SDPWS provisions from the previous WFCM and IBC specifications, and to add new capabilities.
Changes to structural sheathing, plywood siding, and fiberboard, are made to comply with SDPWS Table 4.3A and 4.3B. Unless otherwise noted, these changes have no effect on shear design, but impact nail withdrawal design for C&C loads (see 9 below). This effect is discussed in more detail in that section.
Changes affecting gypsum- and cement-based materials are made to comply with Table 4.3C. Except for the addition of Drywall screws, the do not affect shear design, and these materials have no nail withdrawal capacity as they are not expected to be used in exterior applications for wind design. Therefore the rest of these changes are implemented solely for a more accurate materials specification.
The program now offers the fastener type choice Galv. Box nails for Structural I and Structural Sheathing materials, in addition to the existing Common wire nails. Note that box nails have not been added for the Lumber Sheathing choice.
The same sizes as common nails are implemented – 6d, 8d, 10d, and 16d.
Nail diameters for use in nail withdrawal design are as given in Table A1, Appendix A of the SDPWS. They are smaller than common nails of the same length.
Box nails appear as Box in the Fastener Type column of the Sheathing Materials table. The table legend refers to SDPWS Table A1 for nail diameters and lengths.
The choice of Common wire nails has been removed for plywood siding, to correspond with SDPWS Table 4.3A.
The input choice has been changed from Galv. casing/siding to Galv. casing nails.
Nail diameters for use in nail withdrawal design are the same as for box nails, given in Table A1, Appendix A of the SDPWS.
Casing nails now appear as Casing in the Fastener Type column of the Sheathing Materials table, rather than just Nail. The table legend refers to SDPWS Table A1 for nail diameters and lengths.
The choice of Common wire nails has been removed for fiberboard, as this choice was taken out of the 2008 SDPWS. It was in fact the only choice in Shearwalls 8.
The only fastener type choice is Galv. roofing nail.
The sizes 11 ga, 1-1/2” is the only choice for ½” fiberboard, and 11 ga 1-3/4” for 25/32 fiberboard. .
Nail diameters for use in nail withdrawal design are 0.120 for non-deformed roofing nails and 0.128 for deformed nails.
Previously, the IBC choice for edge nail spacing allowed for only 6” edge spacing. This choice has been removed, and the program allows only the SDPWS spacings of 4”, 3” and 2”.
Roofing nails appear as Roof in the Fastener Type column of the Sheathing Materials table. Nail diameters and lengths now appear in the legend to the table.
The program now allows you to indicate whether nails are deformed (spiral or threaded), so that they use the higher deformed nail withdrawal resistance values.
A checkbox has been added Wall Input View to indicate that a the nails are either spiral or threaded. It can be modified for multiple walls selected together similar to all other inputs.
This is available for common wire nails, box nails, casing nails, and roofing nails used for the structural sheathing, plywood siding, fiberboard, and lumber sheathing types, that is, all sheathing types that are subject to C&C loading for nail withdrawal.
It is incorporated into the definition of standard walls. This is how you would specify a default value. It is also a property of a shearwall that contributes to the distinction of one wall design group from another,
A column named Df has been added to the Sheathing materials table, with entries explained in the legend as Y(es) or N(o).
The choice of Drywall screws has been added to the program for gypsum wallboard, one-ply only, in addition to the existing nail choice.
The size No. 6, 1-1/4” appears for drywall screws.
Shear capacities are implemented as per Table 4.3C. They are lower than the capacities for drywall or cooler nails.
Drywall screws nails appear as Screw in the Fastener Type column of the Sheathing Materials table. The size and length of the screw appears in the legend below the table. .
The fastener type for gypsum wallboard has changed from Cooler nails to Cooler/GWB nails, for both one-ply and two-ply GWB.
There is no longer a choice between 6d and 8d for two-ply gypsum, instead the only choice is 6d base, 8d face, which is shown in the output as 6/8d, and explained in the legend.
There is no longer a choice between 7”and 9” for two-ply gypsum edge and field spacing, instead the only choice is 9b/7f which is shown in the output as 9/7.
The nail lengths and diameters corresponding to 11 ga and 13 ga nails for each of these materials are now given in the legend.
The Fastener Type Choice for Wire lath and plaster has changed to Nails from Screws.
7” edge and field spacing is always allowed. Previously, for the IBC selection, only 4” spacing was included, as per IBC 2006 T2306.4.5.
A note in the legend now indicates that 6d drywall or cooler nails can also be used for 5/8 gypsum sheathing, in addition to the 11 ga nail shown in the table.
No changes have been made for lumber sheathing. Note that box nails have not been added, despite the fact that they are a choice in the SDPWS.