The guard probably saved two lives, Fire Marshal James Tortora said.
“It could have been worse if he didn’t see that,” Tortora said.
The fire marshal said the guard called 911 about 9:30 p.m. Monday to report the fire at 405 Long Hill Ave., a single-family, one-story home.
Two people were sleeping inside the home when firefighters arrived, Tortora said, but were not injured in the blaze.
The fire was confined to an attached garage in the home.
Firefighters from all of the city’s four volunteer fire companies responded, and knocked the flames down in about 15 minutes, the fire marshal said.
The video is from Fireground Images.
Tortora said he ruled the fire accidental after determining it had started in the insulation on the chimney of a wood stove in the garage.
The insulation had either failed or been installed incorrectly, he said.
Damage from the fire was limited to the garage’s back wall and roof.
Tortora estimated the damage at about $10,000.
The house itself is still habitable, the fire marshal said.