Petaluma firefighters doused a garage fire Monday afternoon before it could spread to the main house, a large Victorian on the city's west side.
When firefighters arrived at about 1:30 p.m., heavy smoke could be seen from the detached garage of the house at Sixth and F streets, Battalion Chief Russ Rasmussen said.
No one was in the garage and no vehicles were in it, he said.
Firefighters cut a hole in the roof to release smoke and heat. The flames were under control within several minutes and were confined to the garage.
"The residents were home and are accounted for," Rasmussen said.
A fire inspector was trying to determine the fire's cause of the fire.
Firefighters from Rancho Adobe and Cal Fire also responded, and nearby fire departments handled other Petaluma calls while the city's fire crews battled the fire.