I worked on the 30th floor of the LaSalle Bank Building in Downtown Chicago when it caught on fire. Fire started on the 29th floor right below where I was working. We got out before it spread to the 30th floor. By the time the fire reached my office on 30, the fire had gotten so hot, so intense that it blew the windows out of most of the 29th and 30th floors.
The water damage from that fire reached all the way down to the third level basement in the building. The smoke damage went all the way up to the 43rd floor (top of building) into the board room and corporate dining room. I think every fire clean-up company and crew for 50 miles were working in that building 24x7 for somewhere between 6-8 weeks before the building could be re-opened again above the lobby.
I will NEVER forget that. It was really eerie watching my office go up in flames.
It turns out some HR person was smoking in her office, (this was just after smoking was banned in the office) she threw her ashtray in the garbage can, and poof. She wasn't disciplined because she was a AA hire.