Roland Brass of Marrons examines new analysis that shows almost four in five major residential appeals in the grey belt have been allowed since December 2024, while hundreds of green belt planning applications are currently awaiting determination
When grey belt policy was introduced almost two years ago, there was plenty of debate about what grey belt land is and what its impact would be in relating to delivering more
new homes.
We now have enough evidence to start answering those questions.
Our latest analysis of 355 planning appeals referencing grey belt – covering decisions between 12 December 2024 and the end of August 2026 – shows that the policy has moved beyond being a new concept and has become an established part of the planning system.
The headline figure is striking – 79% of major (10+ dwellings) residential grey belt planning appeals have been allowed, with 30 of the 38 of these major schemes in our analysis successful at appeal.
The allowed rate remains a gamechanger as it is broadly consistent with our previous analysis, which found an 80% success rate from 20 appeals.
We now have almost twice as many decisions, covering a further 12 months, and the success rate has barely moved – making the result more significant, and demonstrating the positive and pragmatic way in which planning inspectors are considering grey belt schemes. This is effectively the “universal tilt” (in favour of granting planning permission) in action and it illustrates the window of opportunity for new homes that grey belt has provided and that this window remains open.
The early results could have been dismissed as a product of a new policy bedding in. However, this is not the case, and importantly a range of land uses (beyond housing) are utilising grey belt.
Scale continues to matter
One of the clearest findings from the latest dataset is the relationship between the scale of a residential scheme and its prospects at appeal.
All seven schemes of 200 or more homes were allowed, as were all seven schemes of between 50 and 99 homes. Seven of nine schemes between 100 and 199 homes were
also allowed.
The picture is different for smaller schemes. Just 34% of minor residential appeals – those involving one to nine homes – were successful. Many of these include permission in principle applications.
Looking at both the major and minor residential outcomes helps to explain why the overall residential success rate has fallen from 55% in our previous analysis to 43%.
The 30 major schemes allowed at appeal represent around 4,004 homes, with an average scheme size of 133 dwellings.
The eight dismissed schemes averaged just 29 dwellings. It is important to acknowledge that the introduction of grey belt land has increased the sources of housing land supply,
alongside brownfield sites for example, as it is a combination of sources of supply that will work to address the housing crisis.
Scale alone will never determine the outcome of an appeal. Every site still has to be assessed on its own merits. But the numbers point to a particularly strong opportunity for larger sites that can deliver housing alongside affordable homes, infrastructure and wider community benefits.
The real test is what follows grey belt
Perhaps the most useful lesson from the latest appeal decisions is what happens after a site has been found to utilise grey belt.
Most of the major residential appeals we looked at cleared that initial hurdle. Only four of the 38 did not, and two of those were assessed under the previous policy framework and failed the now-removed footnote 7 test.
The more significant questions follow: Is there an evidenced unmet need? Is the site in a sustainable location? Would the development fundamentally undermine the purposes of the remaining green belt? And, for major housing schemes, can it meet the Golden Rules?
As set out in the new more rule-based NPPF meeting needs and sustainability of development sites are top considerations for all schemes. For example, walking and cycling connections, accessibility and the relationship with existing and proposed transport infrastructure can all affect the outcome and should be considered early in the design process.
National planning policy has strengthened the grey belt route while introducing another potential opportunity for Green Belt development within a reasonable walking distance of a well-connected railway station. It will be interesting to see how that plays out in practice.
The Golden Rules cannot be an afterthought
For major residential development, the Golden Rules should be part of the thinking from the beginning.
The NPPF continues to require proposals to address affordable housing, infrastructure and accessible green space, with “substantial” weight given to compliance.
Several of the dismissed appeals in our analysis show why this matters. Establishing that a site utilises grey belt does not resolve the other planning issues. Some proposals fell short on the Golden Rules, while others encountered problems with highways, heritage, sustainability or the assessment of the green belt purposes.
For landowners and developers, the practical lesson is to consider the Golden Rules when a scheme is being designed, rather than trying to deal with them towards the end of the planning process.
The same applies to the evidence supporting the wider planning case. The strongest applications will be based on detailed, site-specific evidence and will address the relevant tests directly.
The pipeline is building
The clearest indication of the impact of grey belt policy may actually be found in the number of applications being submitted.
Landstack data shows that more than 700 applications have been submitted on green belt land since December 2024, with more than 400 making a case based on grey belt. Around 600 are currently awaiting determination. That is a substantial pipeline.
What will the next 12 months tell us?
The next year could be particularly significant.
With around 600 green belt applications waiting for decisions, we can expect a significant increase in the number of local planning decisions. Some will inevitably go to appeal, adding to the body of evidence we already have. The key test will be whether local decision reflect the level of success that has been shown in the appeals.
Local Plans will also continue to progress, adding another layer to the picture as councils consider how grey belt fits within their wider approach to housing delivery and green belt release.
There is likely to be further legal testing as well. The past year has already produced High Court judgments and quashed appeal decisions, helping to clarify how parts of the policy should be interpreted. More challenges are inevitable as the volume of decisions increases.
The appeals show that a strong, robust and evidenced grey belt case is essential and that applications must achieve all other planning requirements to succeed. Utilising grey belt is not a guarantee for a planning permission.
Our report is designed to help landowners and developers with suitable sites and to demonstrate that clear opportunity now. It also shows how the more objective (less subjective) assessment process in grey belt policy can have a real impact as grey belt sites allow a range of uses, affordable housing and new infrastructure and open space, while importantly protecting the most valuable areas of the green belt.
But grey belt is not a shortcut through the planning system. The strongest prospects are likely to be sites in sustainable locations, backed by clear evidence of need, a robust assessment of the green belt purposes and a scheme that deals with the Golden Rules from the outset.
With many more green belt applications waiting to be determined the next 12 months are key to the success of the policy to help address the housing crisis and to support the economic development across the country.
