The firefighter went clear through to the basement in the two-alarm blaze on Greenway Road.
Colleagues contained the fire to the kitchen of the two-story, wood-frame house and had it knocked down within 20 minutes of the 10:45 p.m. call, responders said.
It was declared under control a little over an hour after it began.
Fire officials said they were trying to determine the cause.
Other responders included Fair Lawn, Hawthorne, Midland Park, Paramus and Ridgewood firefighters.
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