How much of Britain is built on?

We recently helped out the very talented Alasdair Rae from the Department of Urban Studies and Planning at the University of Sheffield with some research on the buildings of Great Britain. Here is his blog post which is a great work of GIS sleuthery: Buildings of Great Britain

As mentioned in his post we assisted Alasdair by backing up the figures he created using Ordnance Survey’s OpenMap – Local dataset with information from the more authoritative OS MasterMap data.

So what did we find out?  First of all, we had to measure how big OS MasterMap says Great Britain is and instantly we hit an issue, tides.  It was quite tricky trying to unpick what is and isn’t covered when the tide comes in from the OS MasterMap classifications.  After a bit of data wrangling we came up with the fascinating factoid that Britain shrinks and grows by 3454 Km2 twice a day!

infographic-tides

With this settled, we could then move on to figuring out how much of each of the home nations was covered by buildings (at high tide!).  We found 42.5 million objects in OS MasterMap classified as buildings, which we then had to measure and divide up into England, Scotland and Wales. Note that we were just working out the area covered by buildings, not paved areas or roads etc. EDINA has the OS MasterMap data held in a PostgreSQL database with PostGIS installed for spatial analysis like this. Despite the database’s very large size the queries came back relatively quickly from our server, and showed that Alasdair’s figures were very close.  The figures based on OS MasterMap were slightly higher and we think that although generalisation tends to enlarge the building polygons, the inclusion of thousands of smaller buildings omitted from OpenMap – Local accounted for a larger amount.

  • England – 2635.87 Km2

  • Scotland – 316.15 Km2

  • Wales – 195.67 Km2

To give some sense of what these values look like we put them into another infographic for you:

infographic-builtarea

Thanks again to Alasdair Rae for letting us collaborate on his research and for raising such interesting questions we can ask of the data. Thanks also to Ordnance Survey for creating all this data in the first place so we can find these things out!

One last interesting fact that came out of the research was that Great Britain has 22.75 Km2 of glass houses, that’s the same as 3155 football pitches!