Responders were met by flames and heavy smoke at the Fournier Crescent home just after 8:30 p.m.
Hoarding conditions contributed to the extent of the two-alarm fire, which quickly spread to the attic, they said.
One firefighter was injured, though not seriously, responders said. Two cats may have been lost.
The main body of the fire was knocked down shortly after 9 p.m. The blaze was declared under control a little over an hour after that.
Mutual aid included firefighters from Fair Lawn, Lodi and Saddle Brook.
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