Depends on the year & model, but yes. The higher end has fiberglass, but the mid and lower-middle grades are TPO. The very bottom end models may be EPDM (rubber) in recent years, but quite a few were EPDM back in the late 90's and early 2000's.
Former owner of 2004 American Tradition and several other RVs
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC