The fire in the single-story structure at 108 Connecticut Ave., began around 1:15 a.m. Sunday, Dec. 29, Deputy Chief Edward Prescott of the Norwalk Fire Department said.
The renovated building was set to open in January as a barbershop.
The fire was quickly knocked down once firefighters gained entry into the structure, a metal roll-up security door that covered the front of the building and had to be cut open, according to Prescott.
While the fire was contained to the building, firefighters positioned apparatus for any possible extension into a neighboring commercial warehouse, that abutted the building, according to Prescott.
The cause of the fire is under investigation by fire inspectors Dale Roos and Dave Borrows.
Norwalk Police shut down a one-block portion of Connecticut Avenue, while firefighters used the fire hydrant, at fire headquarters, across the street. The road was reopened at 2:30 a.m.
Three engines, two trucks a rescue-and-command car responded to the fire.
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