Systems and methods for automatically generating a 3D model of a roof of a building are provided. In a described embodiment, the method includes receiving point cloud data comprising a plurality of data points corresponding to height measurements at a given location; processing the point cloud data to identify roof surfaces; generating a 3D model of the roof using the identified surfaces; receiving aerial imagery of the roof; registering the aerial imagery with the point cloud data; and refining the 3D model using the aerial imagery. A corresponding computing system and non-transitory computer readable medium for carrying out the methods are also provided.