Cal Fire released their findings on Thursday.
The Tubbs Fire started in Oct. 2017 and, helped by strong wind gusts, exploded in size in a matter of hours.
By the time it was contained later in the month, 36,807 acres and more than 5,500 structures were burned. Officials say 22 people were killed in the fire.
Thousands of the structures destroyed were in Santa Rosa. One neighborhood, Coffey Park, was leveled by the fire.
Bye-bye "Deep Pockets."