What is the Green Belt?
The Green Belt is a policy designation that creates a buffer of open land around urban areas where development is tightly controlled. Green Belts surround many major cities and urban areas in England, covering approximately 13% of the country.
Green Belt land creates a vital buffer between urban areas, preventing sprawl and protecting the countryside
The primary purpose of Green Belt is not environmental protection (although it often has environmental benefits) but to prevent urban sprawl by keeping land permanently open. Each local planning authority defines the Green Belt boundaries in their area through the Local Plan process.
The Five Purposes of Green Belt
As defined in the National Planning Policy Framework (NPPF), Green Belt serves five key purposes:
- To check the unrestricted sprawl of large built-up areas - preventing cities from expanding outward indefinitely
- To prevent neighbouring towns merging into one another - maintaining separation between settlements
- To assist in safeguarding the countryside from encroachment - protecting rural character
- To preserve the setting and special character of historic towns - protecting the context of heritage settlements
- To assist in urban regeneration - by encouraging the recycling of derelict and other urban land
Green Belt is a planning policy designation, not an environmental or landscape quality designation. While Green Belt land often has environmental or agricultural value, this is not the primary reason for its protection. Some Green Belt land may be of poor quality environmentally but still serve important Green Belt purposes.
Development in the Green Belt
The National Planning Policy Framework establishes a presumption against most forms of new development in the Green Belt. The construction of new buildings in the Green Belt is considered "inappropriate development" unless it falls within specific exceptions.
What IS Potentially Allowed in the Green Belt
The NPPF lists several exceptions that are not inappropriate development in the Green Belt:
Building Extensions
Extensions to existing buildings, provided they're not disproportionate additions over and above the size of the original building. Local authorities typically interpret this as allowing extensions up to around 30-50% of the original building's volume, depending on local policies.
Replacement Buildings
Replacement of existing buildings, provided the new building is in the same use and not materially larger than the one it replaces. Some local policies permit replacements up to 10-15% larger than the original.
Limited Infilling
Limited infilling in villages, and limited affordable housing for local community needs. This applies where a village is actually within the Green Belt, not just near it.
Recreational Facilities
Provision of appropriate facilities for outdoor sport and recreation, as long as they preserve the openness of the Green Belt and don't conflict with its purposes.
Agricultural & Forestry
Buildings for agriculture and forestry. These benefit from a specific exemption, though some may still require prior approval for siting and appearance.
Re-use of Buildings
The re-use of buildings of permanent and substantial construction, provided they preserve the openness of the Green Belt and don't conflict with its purposes.
What is NOT Generally Allowed in Green Belt
- New houses (except in very specific circumstances)
- Large extensions that are disproportionate to the original building
- New commercial or industrial buildings (with limited exceptions)
- Any development that harms the openness of the Green Belt
- Development that conflicts with the purposes of including land in the Green Belt
Even if your proposed development falls within one of the exceptions, it must still preserve the openness of the Green Belt and not conflict with the purposes of including land within it. The impact on openness is a critical test for any Green Belt development.
Very Special Circumstances
Inappropriate development in the Green Belt should not be approved except in "very special circumstances." These will only exist if the harm to the Green Belt by reason of inappropriateness, and any other harm, is clearly outweighed by other considerations.
Very special circumstances are not defined in policy and are considered on a case-by-case basis. They might include:
- Essential infrastructure that must be located in the Green Belt
- Development meeting an exceptional public need that cannot be met elsewhere
- Significant economic or social benefits that outweigh the harm
- Environmental benefits or improvements to the Green Belt
For householders, demonstrating very special circumstances is challenging. Personal circumstances rarely amount to very special circumstances, though occasionally factors like exceptional medical needs requiring specific adaptations might be considered.
Permitted Development Rights in the Green Belt
Properties in the Green Belt generally retain their permitted development rights. However, the calculation of these rights is based on the "original house" (as it was built or as it stood on July 1, 1948), and any previous extensions count towards the permitted development allowance.
| Permitted Development Type | Green Belt Restrictions |
|---|---|
| Extensions | Standard PD limits apply (no special Green Belt restrictions) |
| Outbuildings | Standard PD limits apply, but must be for purposes "incidental" to the house |
| Loft conversions | Standard PD limits apply (no special Green Belt restrictions) |
If considering permitted development in Green Belt, it's advisable to apply for a Lawful Development Certificate to confirm your project falls within PD rights. This provides certainty and can avoid potential enforcement issues later.
Green Belt and the "Original House"
The concept of the "original house" is particularly important in Green Belt areas. For planning purposes, the "original house" means either:
- The house as it was originally built, or
- The house as it existed on July 1, 1948 (if it was built before this date)
When calculating whether an extension would be a "disproportionate addition" to the original house, local authorities look at the difference between the original house and the proposed final building, including any previous extensions (even those added by previous owners).
Diagram showing how extensions are assessed against the original house, not the current building
Local authorities vary in how they interpret "disproportionate," but many use a guideline of 30-50% increase over the original house as the maximum typically permitted. Some use volume calculations, others use floor area, and some consider both alongside design factors.
Applying for Planning Permission in the Green Belt
When preparing a planning application for development in the Green Belt, special considerations apply:
Assessment of Openness
A critical test for any Green Belt development is its impact on "openness." Openness has both spatial and visual aspects:
- Spatial openness - the absence of built development
- Visual openness - the visual impact of development on the perception of openness
Your application should address how the development preserves openness or, if there is harm to openness, why very special circumstances apply.
Key Application Considerations
- Volume calculations - Include accurate calculations of the original house volume and the proposed development
- Visual impact assessment - Consider views from public vantage points and impact on openness
- Purposes of Green Belt - Explain how the development doesn't conflict with Green Belt purposes
- Precedent research - Research similar approved developments in your area's Green Belt
- Pre-application advice - Strongly recommended for Green Belt applications
For Green Belt applications, consider including:
- A Green Belt assessment as part of your planning statement
- Photomontages or 3D visualizations showing the visual impact
- Clear volume calculations with methodology explained
- Evidence of the original house configuration (historic maps/photos)
Case Studies: Green Belt Development
Case Study 1: Proportionate House Extension
Project: Single-storey rear extension to a detached house in the Green Belt
Original house volume: 650 cubic meters
Proposed extension: 195 cubic meters (30% increase)
Outcome: Approved under normal planning permission as not disproportionate to the original dwelling
Key factors: The extension was well-designed, used matching materials, and its single-storey nature minimized visual impact on openness. The 30% increase was within the local authority's guidelines for proportionate additions in the Green Belt.
Case Study 2: Replacement Dwelling
Project: Demolition of existing bungalow and construction of two-storey house
Original house volume: 420 cubic meters
Proposed house: 462 cubic meters (10% larger)
Outcome: Approved as not materially larger than the building it replaced
Key factors: While taller than the original bungalow, the footprint was smaller, and the overall volume increase was modest. The design was high quality and enhanced the local environment.
Case Study 3: Outbuilding for Home Office
Project: Garden office in the Green Belt
Proposal: 30 square meter timber garden office for remote working
Outcome: Built under permitted development rights
Key factors: The building was within permitted development size limits, located over 5m from the main house, under 2.5m high (as it was within 2m of a boundary), and for a purpose incidental to the enjoyment of the dwellinghouse.
Common Misconceptions About Green Belt
"Green Belt is an environmental designation"
Green Belt is often confused with environmental designations like Areas of Outstanding Natural Beauty (AONBs) or Sites of Special Scientific Interest (SSSIs), but it is primarily a spatial planning tool to prevent urban sprawl.
While Green Belt land often has environmental or agricultural value, this is not the primary reason for its protection. Some Green Belt land may be of poor environmental quality but still serve important Green Belt purposes like preventing settlement merging.
Environmental designations like AONBs, National Parks, or SSSIs have different purposes and legal frameworks focused specifically on landscape, wildlife, or geological conservation.
"No development is ever allowed in the Green Belt"
While Green Belt policy is restrictive, it does not create a blanket ban on all development. The NPPF clearly identifies several forms of development that are not inappropriate in Green Belt, including:
- Proportionate extensions to existing buildings
- Replacement buildings that aren't materially larger
- Limited infilling in villages
- Facilities for outdoor recreation and sport
- Agricultural and forestry buildings
Additionally, even inappropriate development can be approved if "very special circumstances" are demonstrated that outweigh the harm to the Green Belt.
"Green Belt boundaries never change"
While Green Belt boundaries are intended to be permanent, they can be altered through the Local Plan review process. In practice, this happens relatively frequently:
- Local authorities can review Green Belt boundaries when preparing new Local Plans
- Land can be removed from the Green Belt ("released") if there are "exceptional circumstances"
- Housing need, particularly acute affordable housing need, has been accepted as contributing to exceptional circumstances in some cases
- New land can also be added to Green Belt where appropriate
However, these changes can only be made through the Local Plan process, not through individual planning applications. The process typically takes several years and involves public consultation and examination by a planning inspector.
"My personal circumstances will justify development in the Green Belt"
Personal circumstances rarely amount to the "very special circumstances" needed to justify inappropriate development in the Green Belt. This is because:
- Planning permissions run with the land, not the applicant, so they apply to future owners too
- Personal circumstances are typically temporary compared to the permanent impact of development
- Courts have consistently held that personal circumstances alone are rarely sufficient
In exceptional cases, personal circumstances might contribute to very special circumstances, particularly if related to disability needs that cannot be addressed through alternative means. However, these would typically need to be combined with other planning considerations to outweigh Green Belt harm.
Recent Policy Changes and Future Direction
Green Belt policy has remained relatively stable since the introduction of the NPPF in 2012, but there have been some evolving interpretations and emphases:
- Greater emphasis on housing delivery - The housing crisis has put pressure on Green Belt land, with more local authorities reviewing boundaries to meet housing needs
- Brownfield sites in Green Belt - Increasing support for redeveloping previously developed sites in the Green Belt, provided they don't have a greater impact on openness
- Climate and biodiversity goals - Growing recognition of the potential role of Green Belt in addressing climate change and biodiversity loss
- Permitted development expansions - Some extensions to permitted development rights have affected what can be done in Green Belt without planning permission
Future policy direction may increase emphasis on Green Belt quality and functionality rather than simply its extent, with potential for more nuanced approaches that protect the most valuable Green Belt land while allowing development in less sensitive areas.
This guide focuses on Green Belt in England. While the principles are similar across the UK, specific policies and terminology vary in Wales, Scotland, and Northern Ireland. Always check with your local planning authority for region-specific guidance.