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Planning clarity for Green Belt development: takeaways from Mole Valley v Secretary of State & Meloney 

Overview 

A recent case has reaffirmed planning law principles in relation to Green Belt development policy and site deliverability.

On 15 August 2025, Mr Justice Choudhury handed down his judgment in Mole Valley District Council v Secretary of State & Meloney [2025] EWHC 2127 (Admin), dismissing all three grounds for permission for statutory reviewput forward by the claimant Council in relation to a planning dispute. 

The claimant, Mole Valley District Council, challenged the Planning Inspector’s decision in February 2025 to grant retrospective planning permission for a material change of use from rural land to house residential and touring caravans  in the Green Belt in Dorking, Surrey and to quash an enforcement notice against the same. 

Revised Planning Policy

The Inspector’s decision, and the Court’s judgment in this case, involved interpretation of revised planning policy, in particular the updated NPPF and Planning Policy for Traveller Sites (“PPTS”) both published in December 2024. As well as introducing the concept of ‘grey belt’ land, the updated NPPF introduced a new exception whereby development in the Green Belt should not be regarded as inappropriate where the following criteria are met (at paragraph 155):

1. The development would utilise grey belt land and would not fundamentally undermine the purposes (taken together) of the remaining Green Belt across the area of the plan;
2. There is a demonstrable unmet need for the type of development proposed;
3. The development would be in a sustainable location
4. The development proposed meets the golden rules requirements

Footnote 56 in the updated NPPF explains that “demonstrable unmet need” in the case of Traveller sites means the lack of a 5-year housing land supply of deliverable Traveller sites in line with the updated PPTS. 

The updated NPPF also included at para 153 that “when considering any planning application, local planning authorities should ensure that substantial weight is given to any harm to the Green Belt, including harm to its openness” (emphasised words added in the NPPF 2024).

Harm to openness is defined as, at footnote 55, “other than in the case of development on previously developed land or grey belt land, where development is not appropriate”

Grounds for review/ appeal

The Council’s grounds for seeking review and appeal are summarised below: 

1. Misinterpretation of NPPF 2024 Green Belt policy, in particular that the Inspector erred when not considering harm to the openness of the Green Belt, once he found that the development was not inappropriate. 
2. Incorrect application of PPTS regarding deliverability of Gypsy/Traveller pitches, specifically whether planning applications not yet determined can count as deliverable supply.
3. Failure to provide adequate reasoning in finding that the Council could not show a five-year supply of deliverable Traveller pitches.

These grounds are considered in turn below.

Ground 1: Green Belt Policy and the meaning of “openness” 

The Council argued that the Inspector had erred when treating footnote 55 in the updated NPPF as excluding any consideration of openness harm once a development is found to be “not inappropriate” and concluding that openness cannot be compromised by development that is not inappropriate. 

The Council’s position was that this footnote relaxes the requirement of giving harm to openness ‘substantial weight’ and therefore that the decision maker has discretion to attach at least some weight to the harm, rather than avoiding consideration of harm completely. 

The Court found that the case of Lee Valley Regional Park Authority v Epping Forest DC [2016] JPL 1009 had been correctly decided by the Court of Appeal in its interpretation of Green Belt policy under the (previous) NPPF and in finding that the exception for “buildings for agriculture” was unqualified. Therefore such buildings were automatically regarded as not being harmful to the openness of the Green Belt. Therefore, the consideration of impacts on openness which might otherwise be applied to Green Belt developments did not extend to agricultural buildings on the basis that they were deemed not to be inappropriate development.

The judgment also cited the (non-determinative) Planning Practice Guidance which explicitly set out that where development “is not considered to be inappropriate in the Green Belt, it follows that the test of impacts to openness or to Green Belt purposes are addressed and that following that conclusion a proposal does not have to be justified by “very special circumstances”. 

The judge noted that to interpret the policy in the way the Council sought to would “undermine the purpose of the new exception for grey belt development”: the intention behind which was to permit development that would not previously be permitted. Considering and giving weight to possible harm even where a development would not otherwise be development had the potential, the judge thought, to hamstring this policy change in an unintended way.

Ground 1 was therefore dismissed, the Court finding that:

• Lee Valley had not been wrongly decided. 
• The distinction between ‘inappropriate’ and ‘not inappropriate’ development in considering the effect of openness is one of general application. 
• The Inspector had made a decision consistent with the interpretation of the NPPF in Lee Valley and therefore was not incorrect.

Ground 2: Deliverability of Traveller Pitch Supply

The second ground centred around was whether pending planning applications can count towards deliverable sites under PPTS policy and its footnote 4, which sets out that “to be considered deliverable, sites should be available now, offer a suitable location for development, and be achievable with a realistic prospect that development will be delivered on the site within five years. Sites with planning permission should be considered deliverable until a permission expires, unless there is clear evidence that schemes will not be implemented within 5 years, for example they will not be viable, there is no longer a demand for the type of units or sites have long term phasing plans”.

The Inspector had concluded that over half (35 out of 69) of the Council’s claimed supply related to applications not yet determined, and thus not deliverable. The Council claimed this was a misreading of the law that would require planning permission to be in place/ granted before a site could be considered deliverable. 

The Court found that while permission is not a necessary prerequisite to the deliverability of a site, the Inspector’s decision on deliverability had not solely been made on that basis. Instead, the decision made by the Inspector had been a matter of planning judgment based on matters including minimal evidence in support of the Claimant’s assertions that the relevant pitches would become available and not being able to confirm whether planning permission would indeed be granted for more than half the pitches being claimed. The Inspector considered that there was “minimal evidence” to support any assumption about the likely outcome of current applications or any future windfalls and, on that basis, it could not be concluded that delivery would be achievable or realistically delivered within 5 years. 

Ground 2 was dismissed. 

Ground 3: Adequacy of Reasoning on Supply

The Council also claimed the Inspector failed to provide “legally adequate” reasoning for his conclusion that the five-year supply of deliverable pitches fell short. 

The Council contended the Inspector should have had regard to the Examining Inspector’s Report (“EI Report”) on the Local Plan, even if it was not presented to the Inspector. The EI Report was neither mentioned nor relied on before the Inspector, and no reference was made to it in the Statement of Common Ground. The Claimant argued that, as the Inspector knew the Local Plan had recently been adopted, it should have known that there [SD1] would have been an EI Report and considered it. The Council argued that it was unreasonable for the Inspector not to have regard to a recent evaluation of the deliverable sites that was so obviously material, notwithstanding that no party had drawn the Inspector’s attention to the EI Report.

The judge reiterated the general rule at adversarial hearings that “it is incumbent on the parties to a planning appeal to place before the inspector the material on which they rely” – and that that document had not been considered to be sufficiently material to be included as a relevant document in the Statement of Common Ground. The judge did not accept the Council’s contention that the Inspector should have inquired about the EI Report independently. This ground was dismissed.

Practical points arising from the judgments

The Court’s decision in this case provides helpful guidance for practitioners in the context of Green Belt development and provision of housing deliverability under a Local Plan. 

On interpretation of Green Belt policy under the updated NPPF, the Court’s affirmation of the precedent from Lee Valley, and rejection of the argument that ‘appropriate’ development could still be harmful, is instructive in clearly distinguishing appropriateness and harm in the context of Green Belt proposals.

The judgment also re-states the position that while planning permission is not itself a pre-requisite for site deliverability, it is one element that an Inspector may consider when weighing up whether there is a realistic prospect of development.

The finding that the Inspector had not been required to refer to a report that was not mentioned to him nor put before him indicates that Inspectors will not be obliged to identify and delve into further reports or documents unless they are actively presented by the parties to the appeal – reinforcing the principle that in adversarial hearings it is for the parties to present the evidence and their best case at the appeal.

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