The call to the 30th street residence came in around 10:30 a.m., after the fire ran up the walls.
Flames spread quickly and blew through the roof.
The blaze was brought under control within a half hour but flared up and blew through the roof again, collapsing it.
Firefighters from Elmwood Park and Saddle Brook joined their Fair Lawn colleagues. All units were cleared by 1 p.m.
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