Span is a necessary component of any truss. It is the horizontal distance between two exterior bearings and is typically the width of the structure. Special attention should be taken not to confuse any cantilever portion of the truss with its span. For example, if the walls of the structure are spaced 24’ apart and the truss has a 4’ cantilever on one side, the overall truss length would be 28’ with a span of 24’ and a 4’ cantilever. Truss span can vary widely from as small as 1’ (or smaller if necessary) to over 100’ in length. Truss length is typically limited by manufacturing and transportation capacities for a specific manufacturer. Trusses over 60’ in length are considered ”long span trusses” and require special installation and bracing considerations. Visit SBCA’s website for more information on long span truss installation.
Anyone wishing to order or request a quote for trusses will need to know the span. In simple structures it will typically be the width of the building. In more complicated buildings, it will be taken off the construction documents and likely determined by a truss design and/or layout software specific to the component manufacturing industry.