Previously developed land in the green belt

Brownfield land in the green belt is not a free pass. National policy treats most development in the Green Belt as inappropriate and therefore harmful by definition, and the previously developed land route is an exception within that framework rather than an escape from it. The test is comparative: what effect does the proposal have on the openness of the Green Belt compared with what is already there? Answer that with measurements and viewpoints, and the application has a case. Answer it with an assertion that the site is already brownfield, and it does not.

Start with the definition, because a surprising number of sites that look developed are not previously developed land in policy terms at all.

What counts as previously developed land

The Framework's glossary defines previously developed land as land which is or was occupied by a permanent structure, including the curtilage of the developed land and any fixed surface infrastructure associated with it. The definition carries a caution that it should not be assumed the whole of a curtilage can be developed.

Four exclusions do most of the work in Green Belt cases.

• land that is or was last occupied by agricultural or forestry buildings
• land developed for minerals extraction or waste disposal by landfill where provision for restoration has been made through development control procedures
• land in built-up areas such as residential gardens, parks, recreation grounds and allotments
• land that was previously developed but where the remains of the permanent structure or fixed surface structure have blended into the landscape

That first exclusion catches out more rural schemes than any other. A redundant set of agricultural buildings, however substantial, is not previously developed land, so the redevelopment exception cannot be used. The argument has to run through a different exception, usually the reuse of buildings, or through very special circumstances.

The last exclusion is a question of fact and degree. Concrete bases under bramble, a hardstanding with self-seeded birch across it, the footings of a demolished barn: at some point those have blended into the landscape and the land has reverted. Historic aerial photography and a condition survey are the evidence that settles it.

The Green Belt exceptions that use the definition

The Green Belt chapter of the National Planning Policy Framework, in the edition published on 17 August 2026, lists forms of development that are not inappropriate. Cite the current edition by its policy code and check the wording at the time you write, because the chapter was renumbered in December 2024 and re-issued in 2026.

Two exceptions turn on previously developed land. The first allows limited infilling or the partial or complete redevelopment of previously developed land where the development would not have a greater impact on the openness of the Green Belt than the existing development. The second allows it where there would not be substantial harm to openness and the scheme would contribute to meeting an identified affordable housing need.

The December 2024 edition also introduced the grey belt concept, covering previously developed land and other Green Belt land that does not strongly contribute to the Green Belt purposes, together with golden rules for major development that reaches it. That policy has moved since, so verify the current wording and any transitional arrangements before building a case on it.

Assessing effect on openness

Openness is not the same as visual amenity, and treating the two as interchangeable is the commonest error in these statements.

The Court of Appeal in Turner v Secretary of State for Communities and Local Government held that openness has both a spatial and a visual dimension. The Supreme Court in R (Samuel Smith Old Brewery (Tadcaster)) v North Yorkshire County Council confirmed that visual effects may be relevant but that the weight to give them is a matter of planning judgement rather than a mandatory checklist item. Read together, they mean an assessment has to deal with the absence of built form as a spatial matter and then with how the change is experienced.

A spatial assessment compares quantities: footprint, volume, height, hardstanding, the proportion of the site occupied, the spread of built form across it. A visual assessment compares experience: what is seen from public vantage points, how the change reads against the skyline, whether the development is glimpsed or dominant, and how activity and domestication, such as lighting, fencing, parked cars and garden paraphernalia, extend the perceived built area beyond the buildings themselves.

Do both. An application that scores well on volume and badly on domestication usually fails, because officers have learned to look for the second.

Measuring footprint, volume and spread

The comparison has to be like for like, measured and shown on drawings.

Consolidation helps. A scheme that reduces footprint, cuts volume, lowers the ridge and pulls the built form into one part of the site has a straightforward spatial story even where the number of units rises. A scheme that keeps the same volume but scatters it across the site usually has a greater impact on openness, whatever the arithmetic says.

Be honest about what the existing baseline includes. Buildings erected without permission and not immune from enforcement should not count, nor should structures that have been removed. If the baseline rests on buildings that have gone, the case is for a replacement, not a redevelopment, and the policy test is different.

Evidence that supports a redevelopment case

The bundle that persuades an officer is not long, but every item does a job.

1. A measured survey of existing buildings and hardstanding, with a schedule of footprint, volume and height per structure.
2. Site history: historic Ordnance Survey extracts, aerial photographs and any earlier permissions, establishing the lawful use and that the structures have not blended into the landscape.
3. A drawn comparison of existing and proposed built form, overlaid on the same plan at the same scale.
4. An openness assessment with photographs from agreed public viewpoints, taken at a stated time of year and with the camera positions marked on a plan.
5. Where landscape effects are material, a landscape and visual impact assessment following the recognised methodology.
6. A planning statement that applies the policy test in terms, rather than describing the scheme and inviting the reader to agree.

Agree the viewpoints with the case officer before the photography. A developer who selects flattering positions loses credibility over the whole submission, and the officer will visit anyway.

Conditions that stop the site growing again

Authorities grant these permissions nervously, because a redevelopment that is acceptable on day one can creep. Expect, and ideally offer, conditions that hold the position.

Removal of householder permitted development rights is routine, so extensions, outbuildings, hardstanding and boundary treatments all need permission later. Expect a defined curtilage or domestic garden area shown on an approved plan, with the rest kept as paddock or landscape. Expect control over external lighting, which affects perceived openness at night more than most applicants expect. Expect a landscaping scheme with a long maintenance period, and sometimes a requirement to remove redundant structures and hardstanding before occupation.

Offering those conditions in the application is worth doing. It shows the openness case is being made in good faith and removes the officer's main worry about setting a precedent.

Where the exception is simply not available

Run through the exclusions before spending money. Last use agricultural or forestry: no. Restored mineral working or landfill: no. Garden land in a built-up area: no, and that includes infill plots in villages, which have to rely on the limited infilling exception instead. Remains blended into the landscape: no, and the longer the site has been derelict the harder that becomes.

Where the site sits outside a settlement boundary as well, two separate policy tests apply, and the relationship between settlement boundaries and the countryside policy line can matter as much as the Green Belt designation. If the designation itself looks wrong on the adopted policies map, that is a separate problem with its own route, and errors on a policies map are more common than people assume.

None of which is a reason to abandon a brownfield Green Belt site that does meet the definition. It is a reason to test the definition first and to budget for measurement rather than for argument.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.