by John Flanagan
To add a truss to the underside of a roof, go to the Structure tab and select the Truss tool. If no structural truss families have been loaded, the following request will appear.
Click yes and open the Structural Trusses folder in the UK library and select the Flat Truss, Gable Truss – 6 panel and the simple W Truss. Place a simple W Truss in a plan view following the prompts that appear in the bottom left corner of the Revit Interface. Switch to a section view and adjust the position of the truss if necessary. Change the detail level to Fine on the view control bar in order to see the truss properly.
All parts of the truss have been assigned a wooden element material.
Roof trusses are sometimes used instead of the more traditional rafter construction. For a very simple roof shape, they can be more economical than rafter construction. The diagram below shows a typical roof truss. Note that the diagonal top chord member does not need to be notched to sit on the bearing wall (as in a rafter). Instead, the horizontal member (the bottom chord) of the truss sits flat on top of the bearing wall or beam.
A typical wood roof truss and its supports