Roof Trusses | A Definitive Guide | Aber Roof Truss

A Definitive Guide to the Inner Workings of Roof Trusses

Definition of Roof Trusses

 A roof truss is, put simply, a triangulated system of interconnected structural components, which are often referred to as open web girders. These components are connected and pinned via the nodes, with external forces and reactions at the supports also being applied at the nodes. When all of the components within the truss and the relevant applied forces are in the same plane, creating axial tension or compression, this effect then creates a functioning roof truss.


Further Insight into Truss Structure

 In your average single-story industrial or residential property, trusses are incorporated to serve these two primary functions:


  • To bear the load of the roof – Gravity plays a big part in the trusses ability to hold the roof load (self-load, equipment, snow, wind).
  • To provide stability – Wind girders and vertical bracing in the side walls and gables.


The lateral stability of the properties structure is provided by the truss itself, through the components connected between the truss and columns. For the longitudinal stability of the properties structure, a wind girder is used, together with bracing in the side walls. This allows some of the load to be transferred from the truss and gables to the side walls and foundations.


 Roof Truss Shapes

There are a large range of roof truss shapes to choose from, that provide both structural and aesthetic benefits to properties:

Pratt Truss – A Pratt truss utilises diagonal members that bare the tension of gravitational loads.

Warren Truss­­ – A Warren truss also incorporates diagonal components are in both tension and compression.

Fink Truss – This type of truss is more commonly found in residential properties, rather than industrial.


There is still so much more to learn about roof trusses. If you require further information on roof trusses and how they can benefit your property, do not hesitate to contact the Aber Roof Truss team today.