With the triangular hall type settings, the building type of the selected hall in the hall settings dialog is changed. The roof of the hall is defined as a portal so it has become a gable roof geometry.
Location of the Triangular Hall Type
Select the hall and click the right mouse button. Click the Properties line from the right click menu that opens.
Enter the hall settings.
Select the hall you want to change the roof geometry for from the hall list.
Select the triangular hall from the form type section
The hall you choose will be formed with the triangular roof type.
Hall 1, 2 and 3 view with triangular hall type selected