6 ms·

I beams are quite safe if the fire retardant remains on (a major cause of the WTC collapse was the fire retardant getting blown off by the impact). Trusses on

• newnewpdro 8y ago
  A truss structure is a design not a material though, are you saying all truss designs are dangerous in a fire regardless of material?
  • jdsully 8y ago
    An I beam is also a design not a material, if you want to be pedantic. You can buy aluminum ones.
    • newnewpdro 8y ago
      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.