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In the data group Ignore contribution of...
All gypsum-based materials, fiberboard and lumber sheathing for seismic design
If this setting is selected, gypsum wallboard, plaster materials, fiberboard, or lumber sheathing will be not be considered as contributing to the shear strength of any shear walls designed to resist seismic loads.
You would activate this setting if you are doing both wind and seismic design and wish to have the extra shear strength that non-wood-panels provide for wind design, but do not want the penalty of the increased seismic loading due to smaller response modification factor R that is used when non-wood-panel materials are part of the the seismic resistance system.
Gypsum-based materials and lumber sheathing when combined with blocked wood structural panels or fiberboard in walls with narrow segments
If this setting is selected, the shear strength of lumber sheathing, gypsum plaster and lath, wire lath and plaster, gypsum wallboard, and gypsum sheathing are not considered as contributing to the shear strength or deflection of shear wall segments with an aspect ratio of between 2.0 and 3.5 if and only if there are wood structural panels (WSP) or fiberboard on the other side of the wall.
The reason this setting is to allow full height segments with height-to-width ratios between 2.0 and 3.5 when they have non-wood-panels on one side and WSP on the other side, in order to include the contribution of the WSP . The aspect ratio limits in SDPWS table 4.3.4 are 2.0 for non-wood-panels (gypsum, lumber sheathing) and 3.5 for structural wood panels and fiberboard.
Unblocked Shear Walls
This setting does not include unblocked shear walls as there is no advantage to ignoring gypsum and other non structural wood materials when combined with unblocked walls, as they have the same height-to-width ratio limitation as these materials, 2:1 (SDPWS Table 4.3.4)
Interaction with Allow 3.5:1 Aspect Ratio
When the Allow 3.5:1 aspect ratios setting is unchecked, then this option is unchecked and disabled, as in this case there is no advantage to ignoring the non-wood-panel contribution in terms of avoiding the penalty for a height-to-width ration between 2 and 3.5.
Walls entirely sheathed with gypsum-based materials or lumber sheathing
You cannot set this setting, it is always disabled, and is automatically checked when the Rigidity for shear force distribution setting is set to Shear wall capacity. Its purpose is to inform you of that the restriction based on SDPWS 4.3.3.4.1 is in effect, that is, that only wood structural panels and panels are allowed unless the force distribution is based on deflection analysis.
When this checkbox is checked, any wall that has either gypsum or lumber sheathing on both sides, or those materials on one side and nothing on the other side, is entirely neglected for design, deflection calculations, and capacity-based force distribution.
Precedence of Settings
It possible to have All gypsum based materials... for seismic design checked and Gypsum-based materials... combined with wood structural panels ... in narrow segments unchecked. In this case, the restriction that all these materials are ignored takes precedence and the program disregards the setting pertaining to when they are combined with wood structural panels in narrow segments.
Similarly, it is possible to have Walls entirely sheathed with gypsum-based materials... checked and All gypsum based materials... for seismic design unchecked. In this case, the program ignores the contribution of walls entirely sheathed with non-wood-panels for both seismic and wind design, even though the seismic option is unchecked.
In other words any restriction indicated by a checked box is imposed, regardless of what other boxes are unchecked.
Output
Design Results Notes
The effect of these design settings is indicated in notes under the Sheathing Materials table
Shear Results Table
If the contribution to shear capacity for any shear line in the table has been ignored due to the Ignore non-wood-panel contribution… settings, then a note appears under the shear results table, referring you to the Sheathing Materials table to find out which wall groups were affected.