A Kennewick fire chief says simply shutting a door can keep the fire from spreading, keeping it contained for firefighters.
One of the homeowners says the room where the flames started was unoccupied.
That man was also seen using a garden hose before help arrived; something firefighters urge against because of safety.
With only one fire hydrant on the block, fire crews had to lay 600 feet of hose.
As of Friday (October 10th) night, a cause hasn't been determined.
Investigators say they will return to the house Saturday morning to try and pinpoint what happened.