In late 2010, the 5.87-acre estate served as a double for Gracie Mansion, the official residence of New York City's mayor, for the Jason Statham action movie, Safe, which is scheduled to open in theaters April 27.
The mansion with decorative gardens is located on S. Ithan Avenue near Villanova University.
Wood said the fire originated in electrical wires stapled to the cellar wall in an area under the garage adjacent to a laundry room.
At first, it was confined to the ceiling beneath the first floor, but then traveled horizontally to an area between the laundry room and the breakfast room.
"There was a dumb waiter there with a void in it, and the fire went from the basement through the former dumb waiter shaft to the attic area," Wood said.
From there, the fire spread sideways throughout the storage area on the third floor of the 22-room structure.
Others said the slate roof acted as an oven, keeping the heat under wraps until flames consumed the third floor, finally causing the roof to collapse on arriving firemen. Some were treated for minor injuries.
Immediately after the six-hour blaze was declared under control, Radnor police and Wood began an investigation into the cause.
They called in the Pennsylvania State Police, Delaware County investigators and agents from the federal Bureau of Alcohol, Tobacco and Firearms to assist in the probe.
Agents from each met at the fire scene, April 12, the first time they could get together.
The next day, Radnor Police Chief William Colarulo gave the first hint of movement. He ruled out a reported spark from a nearby construction site on S. Ithan Road as the cause, and gave the go-ahead for construction to resume.
Delaware County District Attorney Jack Whelan said he had heard that the cause was indetermined, though not suspicious.
"It is my understanding that there were some inconsistencies in the original probe," he said. "Therefore we became involved, and the matter is currently under review with our fire investigation unit. However this does not appear to be criminal in nature."
Whelan declined to detail those inconsistencies because he had not yet reviewed fire incident reports.
At the time of the fire, the mansion was occupied by Julie Charbonneau, a Canadian interior designer who specializes in high-end redecoration projects involving French or country-style houses, and Dean Topolinski, a Montreal business mogul. The two have a young daughter, Alexia..
They moved in last August under a lease-purchase agreement with owner Jerald S. Batoff.
When the fire broke out, the family and pets escaped without harm, as an automatic alarm summoned firefighters. But since then, their whereabouts have been unclear.
All three telephone numbers listed to the mansion's address were no longer in service. Charbonneau did not return an email or a call to her web-based business in Montreal. A secretary said she would return the week of April 22.
Contact Bonnie L. Cook at email@example.com.