Krystyna Knight, R (on the application of) v London Borough of Harrow

A permitted-development fall-back may be a material consideration in determining a planning application. Its existence and weight are matters for the decision-maker’s planning judgment, subject to rationality. Information submitted and prior approval obtained under the Town and Country Planning (General Permitted Development) (England) Order 2015 may materially support the existence of such a fall-back.

A delegated planning officer’s report need address the principal important controversial issues with reasons proportionate to the nature of the decision. A concise report may suffice where the report identifies the relevant policy guidance, addresses the principal amenity issue and explains why the proposal is acceptable.

The claimant sought judicial review of the London Borough of Harrow’s decision dated 7 June 2022 to grant planning permission for a single-storey side-to-rear extension and related works at adjoining land. The claimant argued that the officer’s report contained a material mistake concerning an earlier prior approval and failed to give adequate reasons on neighbouring amenity.

The earlier prior approval concerned a larger home extension under Class A of Part 1 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015. The central issues were whether that approval could constitute a planning fall-back and whether the delegated officer’s report adequately explained the amenity assessment.

The claim was dismissed. Neither ground of challenge was established.

1. Fall-back. A fall-back development is capable of being a material consideration. The existence of the fall-back and the weight attributable to it are matters of planning judgment, subject to Wednesbury rationality. The decision-maker need not apply a prescriptive formula.
2. The prior approval notice was material to whether a fall-back existed and to the weight to be given to it. The notice was to be treated as valid unless and until quashed. The enlarged development shown on drawing EX-HWN-400 fell within the relevant permitted-development limits: it did not extend beyond the original rear wall by more than the limit in paragraph A.1(g)(i). The fact that it extended from a side extension did not alter that conclusion.
3. The planning officer’s conclusion was not dependent on the alleged factual error. The officer expressly assessed the scheme as a whole on its own planning merits. Ground 1 therefore failed.
4. Reasons. The report had to address the principal controversial issue, namely residential amenity, but no exhaustive explanation was required. The officer identified the relevant Supplementary Planning Document, considered the adjoining properties, addressed the extension’s depth and the two-for-one rule, and explained why the additional depth was acceptable. It was within the officer’s judgment to assess the impact from visits to the application site without visiting the claimant’s property.
5. The report was adequate for a delegated decision. The claimant had not shown substantial prejudice arising from any lack of reasoning. Ground 2 therefore failed.
6. The court did not need to decide relief under section 31(2A) of the Senior Courts Act 1981. In any event, had a ground succeeded, it would have been highly likely that the outcome would not have been substantially different.