There is a certain obsessive compulsive behavior that motivates some fabricators when it comes to stacking completed trusses and preparing them for shipment to the customer—but did you ever think of the benefits of tight, stacked, aligned trusses?
One of the most difficult parts of a trusses’ life is being shipped and delivered to the jobsite. Banding like trusses together “laminates” them, giving the multiple layers additional strength to resist breakage. This lamination depends on the trusses being banded tightly together using chord sections (and on occasion web) to bond the similar truss panels. The tight banding gives the layers horizontal resistance to relative movement between trusses, providing a stronger lateral truss package. Some fabricators will use a bright nail to nail each truss tail to the next to hold alignment. It makes it more difficult for the erection contractor, but it helps hold trusses in line and contributes to the horizontal strength of the banded pack.
In today’s market, customers and designers often specify a cut up design where very few trusses are the same. For example, forty trusses with thirty eight set-ups is common in some areas. Frequently trusses are stacked in the order they are used on the building. This catering to the customer creates difficult banding situations that may impact the transport and delivery to the jobsite.
There are additional aspects to consider besides shipping considerations. Neatly aligned trusses will emphasize problems in production. Missing plates, misaligned plates, and incorrect profiles are easier to spot when care is used to align trusses. Also a consideration is aesthetics. A poorly aligned pack will set a preconceived notion that the trusses are not consistent. With the cut up design houses, careful stacking of like top chords or stacking bottom chords can often point to set-up issues when the stacker is aware of what to look for in the way of discrepancies. As shown in the photograph, trusses stacked in the order they will be installed requires blocking between dissimilar trusses to provide lamination and rigidity to the banded pack.
Things to remember are:
- Tight banded packs create laminated packages that strengthen the pack.
- A carefully placed nail near the overhang as each truss is stacked can aid in alignment.
- Blocking is absolutely necessary in order to prevent lateral stress on truss members.
- Like trusses should be banded together if at all possible.
- The longer the span, the more bands required.
- Truss labels that are readable in the stack are preferred to help loading verification and make truss identification by the erection contractor quick and simple.
- Neat, tight packaging with trusses aligned give the jobsite delivery a great first impression.
With all of the benefits of neatly stacked trusses, the extra effort is definitely worth the investment.