Extracting elevation values for buildings

In this post, a strategy to obtain the elevation of certain locations (i.e. buildings) is proposed.

First, a digital terrain model (DTM) is needed. In the example, the OS Terrain 50 has been used. This is a 50m gridded DTM, with 10m contours and spot heights, which is provided by the Ordnance Survey. In the next figure, the DTM for the Edinburgh area is shown.

dtm_categories

Note that a ‘Merge‘ operation might be needed if the region of interest is covered by several DTMs.

After this operation, a Digital Elevation Model (DEM) is obtained after the DTM. This raster is created by means of the tool ‘Topo to Raster‘. In this example, an output cell size of 50m was used.

dtm_dem

As illustrated in the DEM, the Arthur Seat, in Holyrood Park, is the highest area in Edinburgh. In the West part of the city, Hillwood Park is remarkable, as well as the Pentlands in the South.

Finally, elevations are extracted from the DEM for all the buildings/regions under study. In this case, the next figure shows the elevation of the properties managed by Historic Environment Scotland (HES) in Edinburgh, which have been extracted by means of ‘Extract multivalues to Points‘.

dtm_to_elevation

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Personalising symbols for point features in ArcGIS

This is a quick trick to personalise the symbols used to indicate the position of features in our maps in ArcGIS. Even if this is a simple operation, a nice visual effect can be obtained.

You just need to open the Symbol Selector > Edit Symbol.

symbol

In the menu Type, choose Picture Marker Symbol. Browse in your folders and choose the image you want to use as icon. Then, select the size and angle and click OK.

In the following map, I have applied this feature to display the properties managed by Historic Environment Scotland in Edinburgh and surronding area.

HESEdinburgh