Engineered Joist
Though this is not particularly referred to as a truss, engineered joists are made in the same manner as how an engineered truss is created. They are also designed by structural engineers and manufactured off-site and installed on site. What makes them different from a truss is the fact that they can be cut exactly to length to fit the requirement but may not be created specifically to fit a certain area in the house. I-joists, in particular, can be used as floor support between the first floor and the crawl space as well as between story levels.
Attic Trusses
Obviously, attic trusses are installed in the roof. These engineered roof trusses come in various designs as well to allow for different uses of the space that is made between the roof and the living space. Some designs have provision for more storage in the attic space while others can limit it and make it very difficult to navigate the space. It depends on the available space within it.
Floor Trusses
Contrary to roof trusses, a floor truss is used to hold up the floor in the structure. It is usually found between the first floor and the crawl space as well as in between any of the living floors. In terms of design, it has the same web-like pattern as the attic truss, with 2” X 4”’s connected with gusset plates.