Greystoke CB Ltd v Secretary of State for Communities, Housing and Local Government & Anor [2026] EWHC 1997 (Admin)

Greystoke is an important Planning Court judgment on the NPPF highway impact test and the planning balance. The court held that paragraph 116 is not confined to cases where highways are the only reason for refusal. It can apply where highways impacts are the principal or main reason for refusing permission. The Inspector also erred by finding a substantial biodiversity net gain and then leaving it out of the planning balance.

Neutral citation

[2026] EWHC 1997 (Admin)

Court

High Court of Justice, King's Bench Division, Planning Court

Judgment date

31st July 2026

Judge

Mr Justice Coppel

Case number

AC-2025-LON-002873

What Greystoke decided

The case concerned an outline application for up to 140,000 square metres of B8 employment floorspace on agricultural land near Junction 11 of the M40 at Banbury.

Cherwell District Council refused the application for 15 reasons. By the end of the appeal inquiry, the principal dispute included the effect of the development on the highway network, particularly Hennef Way and Southam Road.

The Inspector found that the proposed development would not create an unacceptable highway safety impact and that the residual cumulative impact on the road network would be significant but not severe. Even so, he dismissed the appeal, giving substantial weight to the lack of certainty over highway mitigation.

The High Court quashed the decision.

Paragraphs 115 and 116 must be read together

Paragraph 115 of the NPPF requires significant transport impacts to be mitigated to an acceptable degree. Paragraph 116 then says development should only be prevented or refused on highways grounds if there would be an unacceptable impact on highway safety or the residual cumulative impacts on the road network, following mitigation, would be severe.

Mr Justice Coppel held that paragraph 116 supplements paragraph 115. It is not enough to consider the two paragraphs in separate compartments.

The current NPPF still contains the same paragraph 116 highway refusal test, so the point remains directly useful.

Highways do not have to be the only reason for refusal

The Secretary of State argued that paragraph 116 was only engaged where permission was refused solely on highways grounds.

The court rejected that narrow interpretation. Planning decisions nearly always involve several considerations. If paragraph 116 only applied where highways were the single reason for refusal, the policy would have a surprisingly limited role.

At a minimum, the court held that paragraph 116 applies where highways impacts are the principal or main reason for refusal and the planning balance would likely have been different without them.

The Inspector had treated highways as the dominant adverse factor

In Greystoke, highways impacts were the only adverse matter given substantial weight. Locational conflict attracted significant weight, landscape harm moderate weight and heritage harm limited weight.

The Inspector also said his conclusion would remain the same even if the locational policies were out of date and the tilted balance applied. That reinforced the central role played by highways impacts.

On those facts, the court had little difficulty concluding that the appeal had effectively been dismissed on highways grounds for the purpose of paragraph 116.

Paragraph 116 is a material consideration in the balance

The court did not say that non-severe highway impacts must be ignored. Highway impacts remain material considerations and the weight to be attached to them is ordinarily for the decision-maker.

What the Inspector had to do was recognise that paragraph 116 said the development should not be refused on the highways basis he was relying on, because he had found neither an unacceptable safety impact nor severe residual cumulative network impacts.

The Inspector could still have departed from national policy if there were a rational planning basis for doing so. The error was that he never confronted paragraph 116 at the planning balance stage at all.

BNG also had to be carried into the planning balance

The Inspector found that the scheme would achieve a biodiversity net gain of 23% for habitats and 10% for hedgerows and tree lines.

Those gains were recorded in the decision letter, but they disappeared when the Inspector listed the benefits and harms in the final planning balance.

The Secretary of State accepted that it would require a very benevolent reading to say BNG had actually been taken into account there. The court proceeded on the basis that BNG was a material consideration which had to be included and held that Ground 4 succeeded as well.

See our main guide to Biodiversity Net Gain.

The Inspector will have to remake the planning judgment

The court did not grant the planning permission itself and did not decide how much weight highways or BNG should ultimately carry.

The appeal decision was quashed so that the planning balance could be reconsidered lawfully, with paragraph 116 and the BNG benefit properly addressed.

That distinction matters. Greystoke is an authority on how the decision must be made, not a rule that every proposal with non-severe highway impacts must be approved.

Read the full Greystoke judgment

The approved Planning Court judgment is held in the Planning Geek case law library. Gold Members can open the protected PDF below.

Related Planning Geek guidance

Planning Geek covered the judgment when it was handed down in High Court quashes planning refusal over highway impact test. See also the NPPF and BNG pages.

Greystoke Case Law Page Updated: 9th September 2026