A wall area estimation system generates an estimated wall area measurement of a building based on the received roof measurements (e.g., those generated by, received from or found in a three-dimensional model of the roof) and a reference distance. The reference distance is a measurement indicative of a distance between the roof and a model ground surface placed on an image of the building where the walls of the building meet the ground. This reference distance may be used to determine how for down to extend the walls of the building (e.g., to a ground level) when building a three-dimensional digital model of the building to aid in generating wall area measurements. The resulting wall measurements, roof measurements, measurements of areas missing from the wall used to generate a wall estimate report, or a combined roof and wall estimate report including various different identifiers indicating the different features and measurements based on the three-dimensional model.