I had a SE size a beam for me that will be used to support three steel trusses (columns will sit under the two end trusses). In his calculations, he assumed that the load from the trusses was distributed over the length of the beam. The trusses are approximately 14' apart. I'm trying to understand this. Were the trusses 16" or 24" OC, a distributed load is easy for me to see. When sizing a beam or a header, is there a truss spacing at which you would start to consider the loading a point load as opposed to a distributed one?