The four, including two children, evacuated the home when they smelled smoke around 6:30 p.m. at 61 Rampart Road, and called 911, said the Norwalk Fire Department.
The father then went back inside the home to attempt to put out the fire with a garden hose before firefighters arrived, but had to leave as the smoke charged the attic space and started to fill the house, the department reported.
The fire was located in the ceiling and the inaccessible attic space, of a two bedroom addition, to the single story ranch style home, Norwalk fire officials said.
Some 25 firefighters, who responded within minutes, had to pull down the bedroom ceiling and vent the roof to extinguish the flames, which engulfed the attic space.
Heat, smoke and water damage was confined to the two bedroom addition and the family made arrangements to stay with friends until repairs could be made.
Fire Inspector Luca Feola, is investigating the cause of the fire. There were no reports of injuries.
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