Has 92% of the country not been built on?

“But I believe the green belt should be built on and it should be built on soon, because we have, I think there is about 92% of our land mass just not built on at all.”

BBC Question Time audience member, 23 November 2017

The amount of the UK’s landmass that has been “built on” is different to the spread of urban areas. Estimates of how much of the UK isn’t built on range between 88% and 99.9%.

There are several estimates of how much of the UK is urban or built on

Research by the University of Sheffield suggests that “less than 6% of the UK is urban”, using data from 2012.

5.3% of the UK land surface is ‘discontinuous urban fabric’, according to the research—these include areas like suburbs around cities, rural towns and built up areas with lots of gardens, parks and planted areas. Around 0.1% was ‘continuous urban fabric’—areas with buildings and roads covering more than 80% of land surface.

That would mean that 94% of UK land isn’t urban. Analysis of the report by the BBC suggested that 5.9% of the UK is built on and another 2.5% is “green urban”—including parks, cemeteries and private estates. That would suggest around 92% of the UK isn’t built on or urban. This may have been what the audience member was referring to.

Non-urban or built-on land isn’t necessarily free to build on

This doesn’t mean that the rest of the land in the UK is free to build on. 29% is pastures, 27% is non-irrigated arable land (or land where crops are planted), 24% is forest and other natural land (such as beaches or moors), and 11% is wetlands.

There are other studies that measure land use in the UK. Following assessments between mid-2009 and early 2011, a report was published in 2011 by governments and experts from across the UK. It found that “urban areas” made up around 7% of the UK. However, it reports that in England the majority of urban areas are either greenspace, domestic garden, or rivers, canals, lakes and reservoirs.

They found that the rest of the UK is composed of enclosed farmland (40%), mountains, moorlands and heaths (18%), woodlands (12%), and the remainder a mix of freshwater, coastal and marine.

The Office for National Statistics (ONS) published experimental land use data for 2010. The data suggests that 12% of UK land is ‘urban and developed’, which would leave 88% for everywhere else. This is land with homes and other buildings, roads, and urban green space. The rest is agricultural land (65%), forest (13%), marine areas and coastland (2%), and the rest is either freshwater or other types of land.

And the ONS also used the Census 2011 data to show that 10% of land in England and Wales is in ‘built up’ areas. These are areas such as towns and cities that are ‘irreversibly urban in character’. This tells us about the spread of urban areas, but not exactly how much of the UK’s land is actually built on.

A small percentage of new developments are built on the Green Belt

The Green Belt exists to stop cities and towns from spreading or merging into each other, to protect the countryside, to preserve the character of historical areas, and to encourage urban development. It was estimated to cover 1.6 million hectares in March 2017.

The Department for Communities and Local Government produce data on changes in land use in England. In 2015/16, 11% of land changing to ‘developed use’ was previously in the Green Belt. 8% of land changing to ‘residential use’ (homes, gardens and outbuildings) was in the Green Belt.