Methods and apparatuses may include a stiffened beam assembly including a structural beam portion having a web and upper and lower flanges, and at least one continuous stiffening member extending back and forth between the upper and lower flanges on one side of the web, forming one or more trusses or other reinforcing structures. The beam portion and/or the stiffening member(s) may comprise formed sheet metal. The stiffening member(s) may be mechanically attached to the beam portion.