Eli5: how do fire detectives find the start of a large fire? Is it more burnt in that specific area where it started somehow?

Question

Eli5: how do fire detectives find the start of a large fire? Is it more burnt in that specific area where it started somehow?

In: Chemistry

Answer 1

Also interviews with first responders and witnesses. First firetrucks on scene, how fire spread from room to room. Was it in the attic, basement, etc.