The home, at 18 Slinn Ave., in the Hillcrest area of town, was a total loss, according to Sgt. Kenneth Joyce.
The fire started in the northwest corner of the house, police said.
Firefighters from Spring Valley Fire Department battled the blaze with assistance from Hillcrest and Nanuet Fire companies.
All the residents got out safely and have made arraignments to stay with family members, for the time being, he added.
Ramapo Police detectives, Rockland County BCI and the Ramapo Fire Inspector’s Office were also on scene.
At this time the cause of the fire is still under investigation.
Click here to follow Daily Voice Ramapo and receive free news updates.