Wood Wall Results

Wood Wall results are presented in the Wall Panel Design Spreadsheet and the detail reports.

For additional advice on this topic, please see the RISA Tips & Tricks webpage at risa.com/post/support. Type in Search keywords: Wood Walls.

Wall Results Spreadsheets

Wood Wall Axial Results

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Wood Wall Panel Axial

Column	Description
Wall Panel	The Wall Panel column lists the wood wall panels that you have defined.
Region	The Region column lists the wall panel region that the results are based on. Note: For Perforated or Force Transfer Around Openings design methods, regions are not used. Thus, an N/A will be displayed.
Stud Size and Spacing	The Stud Size and Spacing columns show the optimum stud size and spacing chosen for your wall, based on the Design Rules you have defined.
Axial Check	The Axial Check value is a code check ratio between the member load and the member capacity.
Gov LC	The Gov LC column adjacent to the Axial Check column shows the governing load combination for the design.
Chord Size	The Chord Size column shows the optimum chord size chosen for your wall, based on the Design Rules you have defined. Note that the chords are the vertical hold-down members/posts at the both ends of the wall.
Chord Axial Check	The Chord Axial Check value is a code check ratio between the member load and the member capacity
Gov LC	The Gov LC column adjacent to the Chord Axial Check column shows the governing load combination for the design. Note: When running the Segmented design method, the wall panel regions above and below the opening are not considered in design. Thus an NC (no calculation) will be displayed. If there are some constraints that will not allow a wall to be designed, an NC (no calculation) will be displayed. Check the Warning Log within the program for more information on this.

Wood Wall In-Plane Results

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Wood Wall Panel In Plane

Column	Description
Shear Panel Label	The Shear Panel Label shows the optimum shear panel arrangement chosen for your wall, based on the Design Rules you have defined.
Region	The Region gives the region for which the design values are being displayed. Note: The Perforated or Force Transfer Around Openings methods do not consider regions in their design, thus N/A is displayed.
Shear Check	The Shear Check value is a code check ratio between the panel shear load and the panel shear capacity.
Shear Force	The Shear Force column shows the values which governed the design.
Gov LC	The Gov LC adjacent to the Shear Force column show the load combination which governed the design.
Hold-Down Label	The Hold-Down Label shows the optimum hold-down product chosen for your wall, based on the Design Rules you have defined.
Chord Strap Label	The Chord Strap Label shows the optimum strap product chosen for your wall, based on the Design Rules you have defined
Tension Check	The Tension Check value is a code check ratio between the tension load and the hold-down tensile capacity. This column will only be populated for wood walls at the base level of the structure. The program does not do wall to wall strap design
Tie-Down Force	The Tie-Down Forceand Gov LC show the maximum value of hold-down/strap which produced the highest strap force. This maximum force could occur on either end of the wall/region.
Gov LC	The Tie-Down Forceand Gov LC show the load combination which produced the highest strap force. Note: When running the Segmented design method, the wall panel regions above and below the opening are not considered in design. Thus an NC (no calculation) will be displayed. If running a combined RISAFloor and RISA-3D model use RISAFloor to get header results. If there are some constraints that will not allow a wall to be designed, an NC (no calculation) will be displayed. Check the Warning Log within the program for more information on this. If 'default' is shown in the Hold-Down Label column it means that a hold down is not required for this wall/region.

Wood Wall Header Results

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Wood Wall Panel Header

Column	Description
Header Label	The Header Label column shows the label of your header. If there is more than one header in a wall, you can see which is which in the wall panel editor.
Design Rule	The Design Rule column shows the rule that is defining the size and material.
Size	The Size column shows the size from the Design Rule.
Bend UC	The Bend UC column shows the bending code check ratio. This is given for the load combination from the Gov LC column.
Shear UC	The Shear UC column shows the shear code check ratio. This is given for the load combination from the Gov LC column.
Gov LC	The Gov LC column shows the load combination that governed the design. The program finds the largest UC value for either bending or shear and reports the associated load combination here. Note: The Bend UC and Shear UC are always given for the SAME load combination. Whichever load combination produced the highest code check for either bending or shear will have its results shown in these columns. The program will only design wood headers for non-EL and non-WL load combinations.

Wood Wall Self Weight

The program calculates the self weight of a wood wall based on the weights of the individual components. Using the material density, the self weight is calculated for the studs, chords, top plates, sill plates, and sheathing. These are all then summed for the total self weight of the wall.

Wood Wall Detail Reports

The detail report gives detailed information about the wall design. The detail reports are specifically molded to the type of design specified. Here we will walk through how to access the different information for each of the types of design: Segmented, Perforated and Force Transfer Around Openings.

Note:

RISAFloor only considers the Segmented design method. If using RISAFloor together with RISA-3D, simply taking your model into RISA-3D will open up the Perforated and Force Transfer Around Openings design methods.
Many of the values for design checks seen below are not performed in RISAFloor as it is strictly a gravity design program.

Accessing the Detail Reports and the Specific Windows

Once you have a solved model, the detail reports become available. They are accessible in two ways:

If you have the Wall Panel Design spreadsheet open, you can right-click on a line in the spreadsheet and select Detailed Report.
If you are in a graphic view of your model, there is a button that opens the detail report window.

Note: Detail report information is not available for an envelope solution.

Once the detail report window is open, you see an area at the top of the window.

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Detail Report Control Options

Option	Name	Description
	Prior/Next	The left and right arrows let you scroll quickly between the different wall panels in your model.
	Wall Panel Part	The first drop-down list lets you choose between individual Region and Opening (Lintel) results and a summary of the entire Wall.
or	Regions/Headers	The second drop-down list lets you select between different Regions or Openings within the individual wall panel. “R” represents regions, while “L” represents levels (headers). The is available only when ‘Opening’ or ‘Region’ is chosen in the Wall Panel Part drop-down.
	In/Out Plane	If you have selected a Region, then you have the option of whether to view the in plane or out of plane report. The is available only when ‘Region’ is chosen in the Wall Panel Part drop-down.
The following options can be found at the bottom of the Detail Report window.
	Print	Lets you print the Detail Report.
	Add to Full Report	Lets you add the current detail report you are viewing to the printed report. View the Printing topic for more information.

The Wall detail report gives an overall summary of your wall, complete with governing code checks and opening information. The Opening detail report gives information to the header design for the opening as well as detailed information for the Force Transfer Around Openings method. The Region detail report only applies for Segmented walls. Below we have give detailed information on each type of design: Segmented, Perforated and Force Transfer Around Openings.

Segmented Method Results

The Segmented design method uses each of the three detail report windows to give design information.

Wall Window

This window gives an overview of the wall, giving controlling region information and deflection information. Note that this window only gives information on the full-height segments in your wall, as this is the basis of the Segmented method.

Input Echo

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This lists information about the wall, similar to the Region report and also gives an image of the wall. The image shows the location of hold-downs/straps, regions and headers.

Design Summary

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Detail Report - Design Summary

Criteria	Description
Enveloped Results	The Enveloped Results shows the code checks for all of the controlling elements in the wall and their associated load combinations.
Region Information	The Regional Information shows the tabulated results of all of the full-height regions in the wall.
Deflection Results	The Deflection Results shows both the calculated NDS deflection (Maximum Region Deflection) the FE deflection for use as a means of comparison. Because the NDS/CSA O86 equations are empirical and take into account many non-elastic considerations such as nail slip, these two values may not be the same. The use of the SSAF helps to make these two values similar.
Opening Information	The Opening Information states that header design cannot be completed with the Segmented method. The regions above and below the opening have their shear stiffnesses set to be zero and this causes the header forces to be invalid.

Opening Window

This window defines the openings in the wall. The segmented wall design method assumes zero stiffness over the opening, therefore, there is no header design for a Segmented wall with openings. Walls specified as a Perforated or FTAO can be analyzed for a header design.

Region Window

This window gives information for your wall on a region by region basis. Note that only full-height regions of the wall panel will have a region detail report. The Segmented method only considers these full height segments in the design of the wall.

The region detail report is split into four portions: input echo, diagrams and design, design details, and cross section detailing. Note that in RISAFloor the detail reports are less detailed because RISAFloor does not consider lateral forces which RISA-3D does.

Input Echo

Below is the input echo portion of the detail report.

Criteria section

Criteria	Description
Code	Gives the code used to design your wall panel.
Wall Material	Specifies the wood type assigned to the entire wall
Panel Schedule	Specifies the sheathing/nailing schedule database used to optimize panel selection (set in Design Rules)
Optimize HD	Shows whether or not the program needed to optimize the hold-down, or if the user explicitly defined a hold down
HD Manufacturer	Specifies the manufacturer of chosen hold-down
Strap Manufacturer	Specifies the manufacturer of chosen strap

Materials section

Materials	Description
Wall Studs	Specifies the wood material type assigned to the wall studs
Stud Size	Specifies the member size used for the wall studs
Chord Material	Specifies the wood material type assigned to the chords (vertical members at both ends of the wall)
Chord Size	Specifies the member size used for the chords (vertical members at both ends of the wall)
Top Plate & Sill	Specifies the wood material type assigned to the top and sill plates
Top Plate Size	Specifies the member size used for the top plate
Sill Plate Size	Specifies the member size used for the sill plate

Geometry section

Geometry	Description
Total Height	This is the height of the wall panel region
Total Length	This is the length of the wall panel region
Region H/W Ratio	This is the ratio of wall height to length, using the minimum wall height
Cap. Adj (2w/h)	This is an aspect ratio reduction factor for the shear panel strength per NDS SDPWS section 4.3.3.4 Exception 1 (2015). This factor applies only for seismic loads, thus it will be 1.0 for wind load combinations per NDS SDPWS section 4.3.4.1 (2005/8). This factor is applied separately for each full-height region in your wall.
Aspect Ratio	This is an aspect ratio reduction factor for the shear panel strength per NDS SDPWS section 4.3.4.2 (2015). This factor applies only for seismic and wind loads on Segmented or FTAO walls. This factor is applied separately for each region in your wall.
Gov. H/W Cap.	This is the governing (minimum) factor per the Cap. Adj (2w/h) and Aspect Ratios shown above. Only the minimum shall apply per NDS SDPWS section 4.3.3.4 Exception 1.
Wind ASIF	The code gives a 40% increase in the tables if the lateral load is wind over seismic. For seismic loads this ASIF will be 1.0 (only applicable to NDS design). For LRFD 2021 SDPWS, the code allows a 60% increase in capacity when wind load governs over seismic
Stud Spacing	This is the optimized stud spacing based on your Design Rules
K	This is the effective length, K Factor used for stud and chord compression design
HD Eccentricity	This is the eccentricity of the hold-down connection. This is based on the manufacturer's catalog and measured as the distance from the center of the chord to the hold-down bolt

Diagrams and Design

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Envelope Diagrams

These diagrams show the axial forces, in-plane shear, and in-plane moments of the wall, as well as the maximum and minimum forces and their locations.

Note:

The diagrams are not actually enveloped.
- The Axial diagram shown is the diagram from the governing load combination for Stud design.
- The Shear diagram is the diagram from the governing load combination for Shear Panel design.
- The Moment diagram is the diagram from the governing load combination for Hold-Down design.

Design Summary

This portion gives you the capacity and strength values at the section in the wall where the combined check is maximum, as well as the governing load combination. Much of this information is also reported in the Wood Wall Panel Design spreadsheets.

Design Summary Results

Section	Description
Shear Panel	This section displays the Shear Panel code check results. The provided capacity of the shear panel is taken from the Shear Capacity column of the panel database. This is the allowable shear value from Table 2306.4.1 from the 2006 IBC (for NDS design) or Table 9.3A, 9.3B, and 9.3C from the CSA O86-14 (for Canadian design). This capacity automatically considers whether the loading is based on wind or seismic loads. The Governing LC explicitly states if the controlling load combination was based on Wind or Seismic. The program does a unity check for all LCs that are being solved, finds the maximum value and reports that information. Note: A shear panel design will be chosen for the worst-case region in a segmented wall. That panel will then be used for all regions in that wall. The worst-case region is the one that has the highest Shear UC value. Because wind and seismic loading allows for different design capacities, the highest shear in the wall may not be the governing shear (if that highest shear was due to wind).
Chord Design	This section displays the Chord Design code check results. The provided capacities of these members are calculated using the standard provisions for tension/compression members. These members are assumed to be fully braced in the weak axis, and unbraced in the strong axis. For more information on the chord force calculations, see the Wood Wall - Design topic. Note: For chord results, the tension/compression capacity is computed using the reduced cross-sectional properties caused by the hold-down bolt hole.
Stud Design	This section displays the Stud Design code check results. The provided capacities of these members are calculated using the standard provisions for tension/compression members. These members are assumed to be fully braced in the weak axis, and unbraced in the strong axis. For more information on the chord force calculations, see the Wood Wall - Design topic.
Hold Down Design	This section displays the Hold-Down Design code check results. The provided capacity of the hold-down is taken from the Allowable Tension column of the hold-down database. This is information supplied by the manufacturer. Note that we are modifying the Cd value for the hold-down based on taking a ratio of the assumed Cd values from the database and the Cd called for in the Load Combinations spreadsheet.
Chord Straps	This section displays the Chord Straps results. The provided capacity of the chord strap is taken from the Allowable Tension column of the chord strap database. This is information supplied by the manufacturer. Note that we are modifying the Cd value for the chord strap based on taking a ratio of the assumed Cd values from the database and the Cd called for in the Load Combinations spreadsheet.
Deflection	This section displays the Deflection results. The deflection listed in the detail report is based on an approximation from the design code.

NDS Design Deflection

Per the NDS 2015 Special Design Provisions for Wind and Seismic, Equation 4.3-1:

Where:
b	=	Shear wall length,
Δ_a	=	Total vertical elongation of wall anchorage system (including fastener slip, device elongation, rod elongation, etc.) at the induced unit shear in the shear wall, in (This value is taken from the hold down database and scaled per the actual tension force; hence you multiply this value by the holddown ratio given in the output)
E	=	Modulus of elasticity of end posts (chords), psi
A	=	Area of end post (chord) cross-section, in²
G_a	=	Apparent shear wall shear stiffness from nail slip and panel shear deformation, kips/in. (taken from shear panel database)
h	=	Shear wall height, ft
ν	=	Induced unit shear, lbs/ft
d_sw	=	Total shear wall deflection determined by elastic analysis.

The first term of the above equation determines the Bending Component of the deflection.

The second term of the above equation determines the Shear Component of the deflection.

The third term of the above equation determines the Hold-Down Elongation, which causes additional deflection.

Note:

This is the theoretical deflection of the wall. This may differ from the deflection of the wall as performed by finite element analysis within RISA. Therefore, this deflection value may not coincide with the reported deflection value in the deflections spreadsheets. For information on making the FEM deflections similar to the reported deflections from the NDS calculated deflections, see the Shear Stiffness Adjustment Factor information.
For Perforated design deflections, the total deflection is to be divided by C_oper section 2305.3.8.2.9 of the IBC 2006. Because the unit shear values have already been amplified by C_o, the only portion of the deflection that needs to be divided is the hold-down portion.
The hold-down deflection is reported for the maximum shear LC, which may not result in the largest hold-down component, but typically results in the highest total deflection.

CSA O86 Design Deflection

Per the CSA O86-14 clause 11.7.1.2 (or CSA O86-09 clause 9.7.1.1):

Where:
d_a	=	Total vertical elongation of wall anchorage system (including fastener slip, device elongation, rod elongation, etc.) at the induced unit shear in the shear wall, mm. (This value is taken from the hold down database and scaled per the actual tension force; hence you multiply this value by the hold down ratio given in the output)
E	=	Modulus of elasticity of boundary elements (chords), N/mm²
A	=	Area of end post (chord) cross-section, mm²
B_v	=	Shear through-thickness rigidity of the sheathing, N/mm (taken from shear panel database)
H_s	=	Shear wall segment height, mm
L_s	=	Shear wall segment length, mm
ν	=	Induced unit shear, N/mm
Δ_sw	=	Total shear wall deflection determined by elastic analysis.

The first term of the above equation determines the Bending Component of the deflection.

The second term of the above equation determines the Shear Component of the deflection.

The third term of the above equation determines the Hold-Down Elongation, which causes additional deflection.

Note:

This is the theoretical deflection of the wall. This may differ from the deflection of the wall as performed by finite element analysis within RISA. Therefore, this deflection value may not coincide with the reported deflection value in the deflections spreadsheets. For information on making the FEM deflections similar to the reported deflections from the CSA calculated deflections, see the Shear Stiffness Adjustment Factor information.
The hold-down deflection is reported for the maximum shear LC, which may not result in the largest hold-down component, but typically results in the highest total deflection.

Design Details

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Design Details Results

Section	Description
Shear Panel	The Shear Panel section displays the call-out from the shear panel database. The information below it is the information describing the call-out. Note: There will also be an "Adjusted Shear Capacity" that takes the given shear capacity from the design code and divides it by any appropriate adjustment factors from the Geometry section at the top of the report.
Hold Down Design	The Hold-Down section displays the call-out from the hold-down database. The information below it is the information describing the call-out. The "Base Capacity" is the capacity from the manufacturer divided by the assumed Cd value from the database. The "CD factor" that is displayed is the value from the load combinations spreadsheet for the controlling load combination. The actual capacity of the hold-down is the Base Capacity*CD factor.
Chord Straps	The Chord Strap section displays the call-out from the strap database. The information below it is the information describing the call-out. The "Base Capacity" is the capacity from the manufacturer divided by the assumed Cd value from the database. The "CD factor" that is displayed is the value from the load combinations spreadsheet for the controlling load combination. The actual capacity of the chord strap is the Base Capacity*CD factor.

The above section of the report echoes the database information for the selected shear panel and hold-down. For more information on these properties refer to Appendix F-Wood Shear Wall Files.

Cross Section Detailing

The last section of the detail report consists of the wall detailing information. This information is provided as a visual confirmation of the wall design. The wall thickness, and stud spacing are shown as dimensions. The triangle shows sheathing on one side of the wall, with the abbreviated panel designation. The chord sizes/forces and hold down or strap designations/forces are shown at either end. If either chord is only experiencing a compression force, the hold down or strap will not be drawn.

Note: The displayed chord force is not necessarily the force used in the hold-down design because hold-down optimization only considers the governing tension LC.

Perforated Method Results

Opening Window

This window is similar to the Force Transfer information.

Wall Window

This is where the majority of the information is located for the perforated method.

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Perforated Method Wall Window

Section	Description
Criteria (General)	This section displays some of the important parameters in designing the wall.
Geometry	This section displays dimensions and ratios for the wall panel. The Wall H/W Ratio is checked against the aspect ratio limits given in Table 4.3.4 of the NDS 2015 Special Design Provisions for Wind & Seismic (SDPWS). The Max Opening Ht is used in the calculation of C_o. The % Full Ht Sheathed is used in the calculation of C_o. The Full Ht Sheathed is the Sum Li value for C_o.
Materials	This section displays the sizes of the members that are not explicitly talked about in the detail report. Note: The top plate, sill plate and trimmer sizes are used only for the Material Take Off.

Section

Description

Criteria (General)

This section displays some of the important parameters in designing the wall.

Geometry

This section displays dimensions and ratios for the wall panel.

The Wall H/W Ratio is checked against the aspect ratio limits given in Table 4.3.4 of the NDS 2015 Special Design Provisions for Wind & Seismic (SDPWS).
The Max Opening Ht is used in the calculation of C_o.
The % Full Ht Sheathed is used in the calculation of C_o.
The Full Ht Sheathed is the Sum Li value for C_o.

Materials

This section displays the sizes of the members that are not explicitly talked about in the detail report.

Note: The top plate, sill plate and trimmer sizes are used only for the Material Take Off.

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Perforated Method Wall Window

Section	Description
Design Details	The Design Details section displays adjustment factors and some other values used to calculate C_o. See the Wall Panels topic for more information on the Shear Stiffness Adjustment Factor. See the Wood Wall - Design topic for more information on C_o.
Deflections	The Deflections section displays the calculated deflection for the three term shear wall equation from the NDS. See above for more information on deflections.
Wall Results	The Wall Results section displays the following information: Governing LC - The load combination that produced the highest allowable code check. This will also state if this load combination was a wind or seismic LC. Total Shear - The total shear in the wall for the governing LC. Max. Unit Shear - The maximum shear in the shear panel and it is what is used to optimize the sheathing/nailing selection from the shear panel database. Note that the Max Unit Shear may not be the absolute maximum, because shear walls governed by wind are allowed a 40% stress increase. Thus, a wind Max Unit Shear would need to be 40% higher than a seismic Max Unit Shear to govern. Shear Ratio - A ratio of the Max Unit Shear over the Shear Capacity of the shear panel selected from the database.
Selected Shear Panel	The Selected Shear Panel section displays the same shear panel information that was given in the Segmented region report.
Selected Hold-Down	The Selected Hold-Down section displays the same shear hold down information that was given in the Segmented region report.
Selected Strap	The Selected Strap section displays the same strap information that was given in the Segmented region report.
Cross Section Detailing	The Cross Section Detailing section displays a detailed view of the wall. For more information see the Segmented section.

Force Transfer Method Results

Wall Window

This is the overall wall information and is essentially identical to the Perforated method wall window information. There is some geometry information that is not necessary for FTAO that is omitted.

Opening Window

Section	Description
Criteria	The Criteria section gives the code being used and which design method used.
Geometry	The Geometry section gives the opening dimensions and the h/w ratio.
Materials	The Materials section gives dimensions for some of the members in the wall.
Envelope Diagrams	The Envelope Diagrams give the enveloped shear and moment diagrams for the header beam above the opening
FTAO	The FTAO graphic shows the design block numbers around the wall panel opening along with the strap numbers.

Design Details

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The Design Details section is split into two different tables: ‘Opening Straps’ and ‘Analysis Summary’.

Design Details

Section	Description
Opening Straps	The Opening Straps information gives the location, direction, force in the strap and the load combination that caused that force. Note: For more information on how the strap forces and unit shears are calculated, see the Wood Wall - Design topic. The program does not design the straps around the opening, just presents the forces.
Analysis Summary	The Analysis Summary provides the unit shear and the h/w ratio for each of the blocks. The information below the Analysis Summary section is the code check information for the ‘Header’ member. This is identical to the information given for Segmented Window information.

Section

Description

Opening Straps

The Opening Straps information gives the location, direction, force in the strap and the load combination that caused that force.

Note:

For more information on how the strap forces and unit shears are calculated, see the Wood Wall - Design topic.
The program does not design the straps around the opening, just presents the forces.

Analysis Summary

The Analysis Summary provides the unit shear and the h/w ratio for each of the blocks.

The information below the Analysis Summary section is the code check information for the ‘Header’ member. This is identical to the information given for Segmented Window information.