I have two datasets ():   1) A shapefile of buildings containing the height of each building.  2) A parcel shapefile. Several buildings are assigned to a single parcel.   I am interested in calculating the sum of the surface of external walls of buildings (m2) in each parcel. In other words, I want to know how many square meters (m2) of external walls I have in each parcel.  However, it is important for me to exclude those walls which are in common in between buildings. For instance, if two buildings with the heights of 10 m and 6 m are attached from one side, the goal would be to include 4 m of the 10 m external wall and exclude the 6 m which both walls are attached with each other. I hope I was successful in describing the question.
I need to calculate the surface (m2) of external walls of all the buildings in a town. By external walls I mean all the walls of a building or parts of a wall which are not in contact with another building. I have a 2D shapefile of polygons with the cadastral footprint of the buildings, which includes information of the building’s height in the attribute table.  I don’t really know how can I do it… My idea is to convert the 2D file to 3D and use the 3D shapefile to distinguish the external walls from the shared walls (parts of a building that are shared with other buildings) of all buildings, and from there, calculate the total area but I’m not sure whether this can be done with ArcScene.  Anybody knows how could it be done and if there is an automate way to do it?
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