SKOWHEGAN — The fire at the Gov. Abner Coburn mansion on Friday was likely accidentally started while workers were doing repairs on an open spot in the mansion’s metal roof, Skowhegan Fire Chief Ronnie Rodriguez said Saturday.

Rodriguez said the repair workers were cutting steel on the historic house’s roof Friday afternoon where a chimney formerly was. He said an investigation from the Office of State Fire Marshal determined the fire was accidental.

The fire, which was reported to the Skowhegan Fire Department around 3:50 p.m. on Friday, caused “significant” damage to the attic, according to Rodriguez, but he said the house was still “structurally sound.” The second and third floors did see some damage during the fire, but not as seriously as the attic.

Firefighters on a truck ladder inspect the metal roof of the Gov. Abner Coburn mansion Friday in Skowhegan. The fire chief says the fire was likely accidentally started while workers were doing repairs on an open spot in the metal roof. Photo courtesy of Canteen 19.

When fire crews arrived, flames were already visibly shooting upward through the hole in the roof, Rodriguez said. Nobody was in the building when the fire started.

The fire was contained by firefighters from more than a half-dozen agencies — including Skowhegan, Waterville, Fairfield, Norridgewock, Cornville, Anson, Solon and Canaan — around 5:30 p.m. Friday, and was extinguished by 6 p.m. Fire crews cleared the scene at 11:08 p.m., more than seven hours after they were dispatched.

Most of the time spent at the scene, Rodriguez said, was part of the salvage and overhaul phase of the operation, where firefighters check for remaining hotspots in the home and extinguish them.

But the void space in the walls of the Coburn mansion and its sheer size made the process much longer than for most other house fires, Rodriguez said. He said the combined firefighting forces took more than 3 1/2 hours to eliminate all the hotspots in the home. This extra work led Rodriguez to call for additional help twice after the initial dispatch, a move he said he tries not to make because of the strain put on other communities who may have emergencies to respond to.

Firefighters from multiple departments inspect the Gov. Abner Coburn mansion on Friday in Skowhegan. The fire chief says the fire was likely accidentally started while workers were doing repairs on an open spot in the metal roof. Photo courtesy of Canteen 19

The Greek Revival style mansion was once owned by the wealthy Skowhegan native and former Gov. Abner Coburn, who had the house built in the late 1840s. The building was added to the National Register of Historic Places in 1974 and was listed as threatened and among Maine’s most endangered historic resources by Maine Preservation in 1998.

Firefighters respond to a blaze Friday at the historic former Gov. Abner Coburn mansion at 24 Main St. in Skowhegan. Dylan Tusinski/Morning Sentinel

Rodriguez said, while the house is still structurally sound, the loss of some of the house’s historic decor and architecture could prove difficult to recreate.

“That’s the saddest part for me, is the historical value,” Rodriguez said.