I have two datasets (attached):

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.

marked as duplicate by FelixIP, Andre Silva, Midavalo, Dan C, Michael Stimson May 4 '16 at 22:08

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  • Is your shapefile a line or polygon? Why are buildings with common walls represented by several entries? – Adam Kara May 4 '16 at 19:59