Comment

Grey belt – what we have learned

The introduction of ‘grey belt’ has been one of the most debated changes made to the National Planning Policy Framework (NPPF) in December 2024. In this article we consider what we have learned from its first year in operation and what impact it has had so far.

The starting point

Until the updated NPPF of December 2024, Green Belt policy had hardly changed in decades. Governments of all persuasions felt obliged to commit to “protecting our precious Green Belt” (or words to that effect).  

Yes, exceptional circumstances could justify Green Belt release through plan-making. But watered-down housing targets (NPPF 2023) made this even harder to evidence and performance in adopting plans was (and remains) pitiful.  

The effective disallowance of a five-year housing supply deficit as a very special circumstance (WMS of 2015) made pursuing Green Belt release through applications and appeals fraught with risk.

The introduction of grey belt has been a welcome and long overdue response to this damaging impasse.  

What has changed?

Grey belt introduces at least two fundamental changes in the approach to consideration of the Green Belt.

Firstly, it acknowledges that not all Green Belt is of equal value.  

Grey belt policy, and in particular the PPG guidance that accompanies it, enables balanced consideration of the relative qualities and value of parts of the Green Belt. The confirmation of the Green Belt purposes that are most important when considering potential development; the types of settlements to which purposes should apply (or not); and the helpful, real-world illustrations of what is meant by a strong, moderate and weak contribution to these purposes, are of great help to practitioners in establishing the strategic value and purpose of Green Belts and identifying where development can take place without undermining them.

Secondly, it enables a balance to be struck between retaining Green Belts and meeting development needs. 
 
For plan-making, NPPF 2024 made it explicit that if identified needs cannot be met by other means, the use of Green Belt land will be justified. For planning applications, where there is an unmet need for development, proposals should be treated as ‘not inappropriate’ in the Green Belt and the tilted balance can be engaged.

Added to this, development that complies with the “Golden Rules” benefits from “significant weight in favour of the grant of permission”. This applies whether or not the site comprises grey belt – of which more below.

These changes have helped move Green Belt back into the realms of important spatial policy that can support the achievement of sustainable development and away from being a (sometimes wilfully) misapplied means to ignore development needs.  

Effects so far

Early evidence is that grey belt is proving effective in enabling permissions, especially in areas of greatest development need. The PPG guidance on criteria that need to be met to demonstrate a ‘strong contribution’ to purposes a, b or d represent a high bar. Comparatively few sites meet these criteria, and a large proportion of sites therefore potentially qualify as grey belt land. This is surely a powerful incentive for proactive plan-making that ensures development needs are met by allocating the most suitable land to ensure development needs are met.

Many local planning authorities have been proactive in assessing applications in light of grey belt policy and guidance. It had an immediate effect on live applications. Contrary to what may have been expected, this has included development at scale. Sites with capacity for several hundred homes and for sizeable commercial and infrastructure projects are being identified as grey belt.  

When contested at appeal, evidence (focussing on major developments) is that around 75% of appeals, where consideration was given to whether land comprises grey belt, have been allowed. For housing schemes over ten homes this rises to over 80%. Bear in mind that most of the proposals determined so far would have been conceived before the introduction of grey belt and it is highly likely that it will increase in importance as a source of development land.  

It is also evident that the PPG guidance has changed the way Green Belt assessments to support development plans are undertaken. Under the new, more detailed guidance, land which may previously have been assessed as making a strong contribution to Green Belt purposes is being reassessed. We are working on sites that are now accepted as grey belt despite previously having been assessed as making a strong contribution to, for example, preventing urban sprawl.  

The Minister’s recent letter to The Planning Inspectorate calling for a pragmatic approach to the review of Green Belt is further evidence of the significance of the new approach. 

So what have we learned?

While sample sizes are relatively small (and considerations are by definition highly site-specific) it seems that the Government’s intention to open up the supply of potential development sites is being achieved. While the concept of grey belt may have emerged from thoughts of re-using previously developed land in the Green Belt, the policy is of much wider application. Recent research by CPRE suggested that 88% of grey belt sites determined at appeal related to greenfield land.

A policy which has, almost immediately, had such an impact will inevitably be scrutinised. There will be challenge to its interpretation including through the Courts and potential local policy responses to mitigate its effects.  

The High Court has quashed an Inspector’s decision to dismiss an appeal on a site in Beaconsfield. The Inspector concluded that the site was not grey belt but failed to go on to consider the Golden Rules – and therefore, irrespective of the conclusion on grey belt, whether significant weight in favour of permission should be applied. Interestingly, and in the light of PPG guidance and decisions trends, the planning authority has since accepted that the site meets the definition of grey belt.

The Courts have also been asked to consider what makes a village. The High Court recently dismissed a challenge to an Inspector’s decision to allow an appeal in Daws Heath, Essex. The key issue was whether the place in question is a town (or “large built-up area”) where land contributing to preventing merger with its neighbours would NOT be grey belt, rather than a village, where PPG makes clear that no such protection applies.

At least one Local Plan is proposing to designate as towns settlements what have previously been regarded as villages, in order to disapply grey belt policy. This is unlikely to be the only policy response. We can expect renewed interest in concepts such as green wedge; greenway; local landscape designations or local green space that might tilt the planning balance towards protection or create a ‘strong reason’ to refuse permission (per NPPF footnote 7).

There is also a recent case in Shropshire where an Inspector, perhaps surprisingly given that heritage did not form a reason for refusal, concluded that land being within the setting of a listed building triggered the provisions of footnote 7 of NPPF and that as a result the site could not comprise grey belt. There are decisions that have treated this issue differently and is to be hoped that consistent practice emerges swiftly.

As with all significant policy changes it will take time (and a trip or two to the Courts) before this happens.

In the meantime, those promoting developments have the advantage of a positive policy backed by a clear political intent: to increase the amount of development land coming forward in sustainable locations.

So how should practitioners approach identification of grey belt?

If flow charts are your thing, you can download below a summary of the approach.

In essence the key attributes for land likely to be considered as potential grey belt are: 

a) proximity to key features e.g. roads, railways, woodland belts, which can restrict future sprawl in the wider area;
b) containment by existing areas of development on two or three sides such that the introduction of development would not result in an incongruous pattern of development; 
c) not part of a small gap between existing towns, but can form a gap between villages or part of a larger gap between towns;
d) not areas of land with a strong spatial, visual or experiential connection with the settings of historic towns;
e) site boundaries that are clearly defined with permanent features which will form a future defensible edge to the Green Belt; and
f) an absence of footnote 7 areas or assets of importance within or close to the Site that could result in a strong reason for refusing or restricting development.
 

To demonstrate that development would be regarded as ‘not inappropriate’ in the Green Belt, and therefore avoid the need to demonstrate very special circumstances, additional considerations apply:

a) land must not be part of a wider area of strategic importance to the functioning of the Green Belt within the plan area; 
b) there needs to be a demonstrable unmet need for the type of development proposed; 
c) the development needs to be in a sustainable location; and
d) if major development involving housing is proposed, the ‘Golden Rules’ (set out in paragraph 156 of the Framework) need to be met.

And what about delivery?

There is widespread evidence of a surge of planning application activity. Admittedly from a low base, the number of planning applications being submitted show encouraging signs of greater clarity and confidence in the system. One of the country’s biggest housebuilders recently reported plans to have 40% of its land supply in the system within the next two years.  

So we can expect to see the number of planning permissions climbing. But from the Government’s perspective, the real effectiveness of grey belt has to be measured by how it contributes to increased economic activity and availability of homes. This is especially the case for housing where the target of 1.5m new homes completed in this Parliament looks very distant.

Policy change, however effective it is in boosting supply, will not of itself increase delivery. With new construction activity sluggish and home builders reporting sales at a fraction of what would be needed to get anywhere close to the delivery rates that would support 1.5m homes, it is clear that other policy levers need to be pulled. To date, the Government seems reluctant to intervene on the demand side of the housing market but history suggests this will need to be kept under review. 

There remain significant and widespread challenges around the viability of development. For housing, the Golden Rules have increased expectations of affordable housing. At a time when Registered Providers struggle to take up sites, and cost inflation outstrips sales value growth, the challenge is perhaps more acute than ever. The long promised updated PPG on the topic could be pivotal in turning planning permissions into development activity – no pressure then. 

Add to this the Government’s wish to see more social and affordable rent products and that Local Plans are still catching up with plan wide viability appraisal of grey belt sites, and it is clear that while grey belt is a positive and welcome shift, much more needs to shift before delivery can start to address the chronic undersupply of housing and drive economic growth in all areas.

For more information on grey belt, please contact Dave Trimingham, Joanna Ede or Amelia Kinnin. 

15 December 2025