looked like. I read another cathedral, York Minister, had a similar roof fire(though not as extensive) that required rebuilding in the 1980's. I found this cut-away model of the roof design. I would assume the Notre Dame roof was designed just like this. This answers a lot for me, on how the fire could rage in the roof and be unaccessable. And I've heard people talk about sprinklers for fire suppression stopping something like this. Well, look at the construction. Sprinklers would have done nothing here, even if they were installed somehow.