Exploring the slopes of roofs on residential and commercial buildings.
Using the Environment Agency’s opensource 1 m LIDAR data, I calculate the roof angle on the Cardington Airship Sheds to be about 33 degrees from the horizontal. If the data were finer at a resolution of 0.5 m or 0.25 m, results would be more accurate on smaller residential property roofs. Using edge detection and other refining techniques, buildings of a known roof design can be classified.
See the following notes on the calculation of slope in ArcGIS.