Understanding UK land types

January 2025

Many people recognise different types of land, even if they are unclear on the definitions. Common terms like 'green field' and 'brownfield' describe the status of the land, while others have specific legal meanings that impact planning decisions. It is essential to avoid confusing these terms.

Brownfield is previously developed land, such as industrial sites or areas containing disused factories, unused community buildings or shopping centres. It does not include land occupied by agricultural buildings or land subject to restoration plans, meaning it can also exclude quarries or landfills.

Green field sites are sometimes mistakenly interchanged with green belt. Green field areas cover land that has never been previously developed. They could include agricultural fields, pastures, and farmland. The term green belt was introduced under the Town and Country Planning Act in the 1940s to protect the countryside from urban sprawl.

Until recently, the grey belt was an unfamiliar term to many. Now, with the government's focus on housing and its target for 1.5 million new homes to be built over the next five years, it is an ideal time to better understand UK land types. 

What is grey belt land?

The term ‘grey belt land’ refers to areas of land that are deemed to be of low quality and low environmental importance, located within designated green belt areas. The concept of the grey belt was introduced to allow for the release of certain protected lands from green belt restrictions to address local needs while adhering to sustainable development principles.

The government recently defined this as ‘green belt land, which makes a limited contribution to the green belt’s purposes.’ So, while still protecting areas of particular importance, it can provide opportunities for the development of land with at least one of the following features:

  • land containing substantial built development, or which is fully enclosed by built form
  • land which makes no or minimal contribution to preventing neighbouring towns from merging into one another
  • land, which is dominated by urban land uses, including physical developments
  • or land which contributes little to preserving the setting and unique character of historic towns.

 

Can grey belt land help deliver ambitious housing targets?

Planning policy emphasises the importance of prioritising brownfield sites for development. However, only 9% of land in England is classified as brownfield. By utilising the grey belt, it may now be possible to release around 3% of England's green belt. This initiative could lead to the creation of over 300,000 new homes. Furthermore, new regulations would mandate that half of the dwellings constructed in the grey belt be designated as affordable housing, which is greatly needed.

However, developing grey belt land can offer both challenges and opportunities. The technical complexity should not be underestimated and may still require ground pre-treatments, remediation or engineered solutions. These areas may also lack some critical infrastructure, such as roads and utilities which would be present in most brownfield locations.

Land Remediation

NHBC is the leading warranty and insurance provider for new homes in the UK. Its commitment to ensuring build quality and raising standards in the house-building industry also includes land remediation.

NHBC works with leading developers to help them get it right the first time. Our Land Quality Service (LQS) removes uncertainty about whether a site is suitable for future housing development.

Last year, our experienced team of geotechnical and geo-environmental engineers assessed land to enable the release of 120,000 plots, supporting developers, landowners and house builders in meeting their targets for current and future supply needs.

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