Secondary - Default Options

(Revised: 04/09/2024)

The Secondary Options tab is used to describe general options of the Secondary, including the Frame and Secondary Offsets as well as the Flange Brace, Grouping, and Nesting options.

Discrete Bracing:

Not Required

This is the default, use this option if erection Channel Purlin Braces are NOT desired. Channel Purlin Braces may be system generated when designing purlins with SSR / SLR II / VSR II roof panel.

Required for Erection

Select this option if erection Channel Purlin Braces are desired.

Erection Channel Purlin Braces will be located based on bay spacing and purlin member length. A maximum of (4) Channel Purlin Braces per bay can be supplied as long as the bay is wide enough to fit (4).

Canadian Requirements

Use this option if Channel Purlin Braces need to be designed per the Canadian Building code.

Omit SLR Bracing

Select this box if SLR designed Channel Purlin Braces are not desired. Purlins may be heaver due to reduced brace points for design.

Flange Brace:

Flange Brace - Available

The Flange Braces - Available radio button defines the secondary to frame intersection can be used as a supported location during the design of the primary and secondary.

Flange Braces may or may not be required at this location(s), depending on the final design.

Flange Brace - Not Available

The Flange Braces - Not Available radio button defines the secondary to frame intersection cannot be used as a supported location during the design of the primary and secondary.

Flange Braces will not be designed at this location(s), regardless of the final design.

Connection

Option allows user to select different flange brace connections as defined in pop-up window. This will override the Insulation screen.

Design Information:

Group Secondary Thickness

This check box, when selected, allows the secondary members of the same geometry (simple vs. continuous, zee vs. cee) in a bay (roof or wall) to be detailed as the heaviest designed thickness required in that bay.

Caution should be used when checking this box since the weight and cost of the project will be increased when this option is selected.

Maximum (Factored) Strut Load

Enter the Maximum Strut Load that can be applied to the design of the Secondary Member(s). Factored strut loads larger than the entered value will generate independent bracing struts.

Override Stress Limit

0.00 indicates the system will use 1.03 Allowable Stress Ratio when designing Secondary Member(s). Enter a value less than 1.03 only if required by the project specification.

Modify Spacings per Panel Design

This check box, when selected, allows the secondary spacing to be automatically modified during design, based on panel design criteria.

Purlins in full length zones which includes the field, ridge and eave will automatically be spaced by the system. Rake and corner zones are checked and wind zone sub-secondary members are added when needed. However, the Edit Check report will display messages when panel design issues cannot be resolved.

Secondary By Others:

Secondary Members By Others

This check box, when selected, indicates that the Secondary Support Members will be supplied by Others. The Weight edit box will be enabled and required when this option is selected.

Secondary connections (holes and clips) will not be generated for this member type. Do NOT use this option for entering Bar Joists.

Weight

Enter the weight of the Secondary Members that are By Others. This information is required during the design of the primary framing system.

Secondary Offset to Building Line:

Secondary Offset to BL - From Secondary Flange Outside

The Secondary Offset to Building Line - From Secondary Flange Outside radio button designates the Outside Flange of the Secondary to be the dimension line, used in conjunction with the Secondary Offset Dimension edit box.

The Secondary Offset to the Building Line Dimension can be adjusted to recess the secondary further into the building. A positive dimension moves the secondary into the building, a negative dimension moves the secondary outward from the building.

„ Notes:

If the Frame Offset radio button is: Match Secondary Depth (Outset), then primary frame location will be adjusted by the Secondary Offset.

If the Frame Offset radio button is: Dimension to Building Line, then the Secondary Offset will not affect primary frame location.

Secondary Offset to BL - From Secondary Center Line

The Secondary Offset to Building Line - From Secondary Center Line radio button designates the Center Line of the Secondary to be the dimension line, used in conjunction with the Secondary Offset Dimension edit box.

„ Notes:

This option is rarely used, but could be very useful at interior partition walls.

Secondary Offset to BL - Dimension to BL

The Secondary Offset to Building Line - Dimension to Building Line edit box measures the distance from the Building Line to either the Outside Flange or the Center Line of the Secondary, as selected by the radio buttons.

The Secondary Offset to the Building Line Dimension can be adjusted to recess the secondary further into the building. A positive dimension moves the secondary into the building; a negative dimension moves the secondary outward from the building.

„ Notes:

This option is rarely used, but could be very useful at interior partition walls.

R-Factor:

R-Factor - Inside Flange (R-f1)

This is determined by AISI code and will be system generated. Enter the R-Factor of the Secondary Members Inside Flange if overriding the system value.

R-Factor - Outside Flange (R-f2)

This is determined by AISI code and will be system generated. Enter the R-Factor of the Secondary Members Outside Flange if overriding the system value.

User can view these R-f1 and R-f2 fields on the Expanded Secondary Design Report in the section labeled Secondary Design Member Section Properties. See example below.