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Important Note – These are descriptions to changes implemented in WoodWorks Shearwalls for version 11 and may not reflect current program behavior.
Version 11 of Shearwalls updates several design codes and standards used in the program. The details of the associated changes to the program appear throughout the rest of this list of changes; this section just identifies the design standards changed.
The implementation in Shearwalls of the IBC has been updated from the 2012 edition to 2015, the NDS from 2005 to 2012, and the SDPWS from 2008 to 2015
Version 11 of Shearwalls implements the 2015 IBC, whereas Version 10 implemented the 2012 version.
IBC 2015 references the AWC Special Design Provisions for Wind and Seismic (SDPWS 2015) for all design provisions*, whereas IBC 2012 referenced SDPWS 2008. Extensive changes for the 2015 SDPWS edition were implemented, as described in .
IBC 2015 continues to reference ASCE 7-10 for all wind and seismic load generation procedures. Since both Shearwalls 10 and Shearwalls 11 implement ASCE 7-10, no changes were needed for these provisions.
*except those using staples, which are not permitted by SDPWS. Shearwalls does not include staples, so all procedures in the program comply with IBC by complying with SDPWS.
The SDPWS had been updated from the 2008 version to the 2015 version for Shearwalls 11. The most consequential changes are listed here and described in more detail in later sections of this document.
Deflection-based distribution is established as the preferred method of allocating forces to segments within a shearline. Capacity-based distribution is restricted to wood or fiberboard shearwalls, and a more stringent aspect ratio factor is applied to the strength of narrow shearwall segments when it is used.
Previously, the strength of a perforated wall was factored by the aspect ratio factor for the narrowest segment in the wall. Now, the length of wall used to determine the Co factor is adjusted instead, leading in general to much lower penalties for narrow segments.
The design code clarified what is meant by the restriction to similar materials and construction on a shearline, so that shearwalls with differing sheathing thickness and nailing patterns are now allowed on the same line, as long as they belong to the same class of materials (wood structural panels, gypsum wallboard, fiberboard, etc.)
Although it is not explicitly mentioned in the SDPWS, in communications with WoodWorks AWC confirmed a that the same redefinition of similar vs. dissimilar materials should be used when combining sheathing capacities from materials on opposite sides of the wall.
A new provision requires that the deflection fiberboard segments with an aspect ratio greater than 1:1 be increased by the square root of the aspect ratio.
The out-of-plane sheathing capacity for resistance to C&C wind loads has changed for some materials.
Version 11 of Shearwalls conforms to the NDS 2015, whereas version 10 conformed to NDS 2012. There are very few procedures in the Shearwalls program taken directly from the NDS, as all shearwall and diaphragm provisions are now in the SDPWS, to which the NDS refers. None of the provisions taken directly from the NDS have changed for this edition.
The references to design standards have been updated in the following places:
The new design standards implemented are listed in the Welcome dialog box that appears on program start-up, and can be invoked later via the Help menu, and in the About Shearwalls box from the Help menu. More detailed information is given in the Building Codes dialog box invoked from the Welcome box.
In the Building Codes dialog, the reference to the NDS clause that references the SDPWS has changed from Chapter 14 to 1.1.1.4.
The log file, which gives the equations used for wind and seismic load generation and for torsional analysis, has been updated for the new design code references.
The header to the log file now says that it implements IBC 2015 and SDPWS 2012, as well as the existing ASCE 7-10 references.
The On-line Help documentation has been updated to refer to the current design code editions.
Where necessary, references to design code clause numbers in program messages, notes, table legends, etc., have been updated, as follows.
In general, clauses were added to the SDPWS but the existing provisions kept their original numbering. There were no instances of changes to SDPWS clause numbers in the program.
References to clauses from Chapter 10 of the NDS were incremented to Chapter 11, and Chapter 11 to Chapter 12. References in Shearwalls to 10.3.6 for fastener slippage were changed to 11.3.6, and nail withdrawal capacity 11.2-3 was changed to 12.2-3.
The few design code clause references that have changed have not yet been updated as within the On-line Help as of the date of the software release. The Help is now accessed over the Web, and will have the updated references by Feb 2017.
The WoodWorks package no longer installs a .pdf files for the On-line NDS and On-line SDPWS on your computer. The Help menu links and Start menu icons now direct you to websites where viewable versions of the NDS, the NDS Supplement, and the SDPWS are accessed.
Note that the NDS Commentary is no longer included.
In the Building Codes dialog box that is accessed from the Welcome box:
A note has bee added saying that nail withdrawal and hold-down bolt elongation procedures are taken directly from the NDS design standard.
The reference to the removal of the 1997 UBC design code has itself been removed