The speed and intensity of the blaze made an initial search of the Macopin Road house impossible, responders said, adding that firefighters later learned that no one was home.
Mutual aid companies from Highland Lakes, Kinnelon, Pompton Lakes, Ringwood, Upper Greenwood Lake and elsewhere assisted their West Milford colleagues, who requested tankers after the blaze broke out in the 2½-story Cape Cod, south of Bubbling Springs Park, just after 8:45 p.m.
The fire went to four alarms a little over an hour later and then a fifth 20 or so minutes after that. It was declared under control shortly after 10:30 p.m.
Township fire officials also summoned the Passaic County Prosecutor's Arson Unit.
A utility crew was needed to address downed power lines and DPW workers to salt the icy roads.
Click here to follow Daily Voice West Milford and receive free news updates.