Spans tab

You can quickly define all the elements of the structure that you wish to add using the top row of icons in the spans tab. Selecting each option will add a tab where you can define the relevant information for that element.

In this Spans tab you can define the main portal information including number of spans, and span length, section size and grade, rise of the rafter, and the haunch length and haunch depth ratio for each individual span. You have the option to select a mono-pitch and specify the direction of slope. A mansard roof can also be defined by giving the length of the top flat portion.

Note:- If the Optimise Apex/Eaves Haunch option from the General tab is selected, then the depth of the apex and eaves haunches are calculated automatically and cannot be user-specified.

Tip:- The rise of the rafter can be expressed in metres, degrees or as a slope. To set the rafter rise using degrees, use an asterisk, for example 22.5*. To set the rise with a slope, use a forward slash, for example, 4/ indicates a 1 in 4 slope.

Key Principle:- Leaving the 2nd and 3rd rows blank means that they will default to the information entered in the 1st row. This is a general principle used throughout the software. It also means they are in one design group and will be designed to use the same section size and purlin spacing arrangement. However, if you want the rafters in each individual span to be in separate design groups, you should specify section sizes for each span. This applies particularly to frames with spans of different length, where the section sizes of the rafters are likely to vary for each span.