The 59-year-old contractor fell from one level of the roof to another at a Woodland Park Drive home shortly after 3 p.m., Police Chief Robert Chamberlain said.
Firefighters climbed up and lowered the victim down in a Stokes basket, assisted by police, Chamberlain said.
The Tenafly Volunteer Ambulance Corps took him to Hackensack University Medical Center for treatment, the chief said.
Click here to follow Daily Voice North Hunterdon and receive free news updates.