Continuous Members

Members that are continuous over a support force more load to the center support than two simply supported members on each side of the center support (joist not continuous over the support). The carrying beam must support more than 1/2 of the load from each side span -- it is 5/8 when the two spans are equal, even more when the spans are not equal.

Try experimenting with RedSpec™ and check the intermediate reactions while changing the length of the span on each side of the intermediate support.

Multiple spans are not allowed for open-web truss design. Trusses may be continuous over exterior bearings, which is to say overhangs are allowed.

Minimum Overhang Length

I-joist and beam overhangs less than 6" long are not considered as overhangs in the analysis. The support in such a condition is treated as an end bearing rather than intermediate. RedSpec, however, does not allow input of overhang lengths less than 6".

For open-web trusses, the minimum length of an overhang is 12".