Amin Dharmeshkumar v Secretary of State for Housing, Communities and Local Government & Anor

Works fall outside the statutory exclusion for maintenance, improvement or alteration where they materially affect the external appearance of a building. The assessment is one of fact and degree, informed by the nature of the building and the works. The effect on a part of a building may suffice.

Where works partly comply with a planning permission, only the non-compliant works are unauthorised. For a prior approval granted under the GPDO, paragraph W(12)(a) requires development to accord with the approved details. If the approval refers to non-existent plans, the resulting ambiguity may be resolved by considering the application material.

The appellant challenged an inspector’s dismissal of his appeal against an enforcement notice concerning the use of a former office building as twelve flats. The challenge was brought under section 289 of the Town and Country Planning Act 1990.

Permission was granted for specified building works, and prior approval was granted for an office-to-residential change of use under Class O of Part 3 of Schedule 2 to the GPDO. The inspector concluded that the building works constituted development requiring permission, that the works did not comply with the approved details, and that the appellant could not rely on the permitted development right. The issues were whether the inspector had erred in applying section 55 of the 1990 Act and whether he had lawfully interpreted the prior approval by reference to extrinsic material.

1. Ground 1(a) dismissed. Section 55 requires a sequential analysis. Building operations within section 55(1A) may nevertheless be excluded from “development” by section 55(2). The exclusion in section 55(2)(a) requires both that the works are for the maintenance, improvement or other alteration of a building and that they affect only the interior or do not materially affect the external appearance.
2. The question whether works fall within the description of maintenance, improvement or alteration is one of fact and degree. The four possible outcomes identified in Hewlett v Secretary of State for the Environment remained apt. The works did not produce a wholly new building, but the changes to the fenestration could materially affect the appearance of part of the building. That was a planning judgment for the inspector and was rationally open to him.
3. Following Hillside Parks v Snowdonia National Park Authority, works which partly comply with a planning permission and partly depart from it are not wholly unauthorised merely because of the departure. Only the non-compliant works require separate authorisation. This did not alter the conclusion on the fenestration.
4. Ground 2 dismissed. Paragraph W(12)(a) of the GPDO requires development, where prior approval is required and granted, to be carried out in accordance with the approved details. The relevant terms of a prior approval are not confined to the description of the use. A reference to two plans which did not exist created an ambiguity. It was therefore permissible to consider the application material to resolve it. The inspector was not entitled to rely on the parties’ subjective understanding, but his decision did not do so.
5. The challenge to the costs decision was parasitic on the substantive challenge and therefore also failed. The challenges to both decision letters were dismissed, leaving the partial costs award undisturbed.

• High Court (Planning Court): Permission to pursue grounds 1(a) and 2, and the related costs challenge, was granted by Deputy High Court Judge Ridge in [2025] EWHC 169 (Admin). The substantive challenges were dismissed.