The blaze started on the outside of the three-story home in Norwalk on East Beach Road around 11:15 a.m. Sunday, April 4, according to authorities.
Power lines to the home ignited and were arching, which delayed extinguishment, the Norwalk Fire Department said.
Once the power was off, the Rowayton Fire Department quickly extinguish the fire.
Darien and Norwalk Fire were also on the scene for assistance.
"The fire is still under investigation, but probably started when discarded ashes from the fireplace ignited," Norwalk FD Deputy Chief Steve Shay said.
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