South Darenth Farms challenges enforcement notice over permitted development rights and the Murfitt principle

The High Court has refused permission for a statutory appeal challenging an inspector's decision to uphold an enforcement notice, despite acknowledging an error in the inspector's reasoning regarding permitted development rights under the Town and Country Planning (General Permitted Development) (England) Order 2015.

HHJ Karen Walden-Smith, sitting as a Judge of the High Court, delivered judgement on 16 October 2025 in South Darenth Farms and Cold Store Company Limited v Secretary of State for Housing, Communities and Local Government & Others [2025] EWHC 2646 (Admin). The case centred on enforcement action taken by Dartford Borough Council against unauthorised mixed use development at the Hawkspare Site in Green Street Green Road, Dartford.

South Darenth Farms, lessee of the eastern portion of the site known as Fairfield, had appealed the enforcement notice on multiple grounds. The company argued that retaining walls and fencing up to 2 metres in height constituted permitted development under Class A of Part 2 of Schedule 2 to the GPDO and therefore did not breach planning control.

The inspector had rejected this argument by applying Article 3(5) of the GPDO, which states that deemed permission does not apply where the existing use is unlawful. The Secretary of State conceded through counsel that this was an error – Article 3(5) did not apply to Class A permissions as they are not granted "in connection with an existing use."

Despite this acknowledged error, the court refused permission to appeal. The judgement turned on the application of the Murfitt principle, established in Murfitt v Secretary of State for the Environment (1980) 40 P & CR 254. This principle permits enforcement notices directed at unauthorised changes of use to require removal of associated works that are "integral to or part and parcel of" the unauthorised use, even where those works might otherwise benefit from permitted development rights or have become immune from enforcement.

The court examined the evolution of this principle through subsequent cases, particularly Kestrel Hydro v SSCLG [2023] PTSR 2090, where Lindblom LJ clarified that the principle applies to works integral to unauthorised use but not to works undertaken for lawful use or capable of being employed for lawful purposes once the unauthorised use ceases.

The enforcement notice had explicitly described the retaining walls and fences as "facilitating" the unauthorised material change of use. South Darenth provided no evidence that these structures served any purpose other than facilitating the unauthorised development. The judge found it inevitable that, had the inspector properly considered the matter, he would have concluded the structures were part and parcel of the unauthorised use.

The court rejected South Darenth's argument that GPDO rights created an exceptional class immune from the Murfitt principle. The judge held that permitted development rights do not override the statutory enforcement scheme where works are integral to an unauthorised use and merely ancillary rather than fundamental or causative of the change itself.

Applying Simplex GE (Holdings) Ltd v Secretary of State for the Environment [2017] PTSR 1041, the court concluded that even without the error regarding Article 3(5), the inspector would necessarily have reached the same decision given his findings on Green Belt harm, landscape character impact, and effects on neighbouring occupiers' living conditions.