That's fair, but I know of no aluminum I-beams used in modern highrise construction which is the context of my sentence. Truss roofs are made from steel of var

That's fair, but I know of no aluminum I-beams used in modern highrise construction which is the context of my sentence. Truss roofs are made from steel of various shapes, even I-beams, and wood. I'm only asking for clarification if all truss designs regardless of material are problematic in a fire.