Appeal 3280760

The appeal is allowed and planning permission is granted for a single-storey rear extension at [site address] , [site address] , [site address] [postcode] in accordance with the terms of the application, Ref 21/01120/FUL, dated 16 March 2021, subject to the following conditions:

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the following approved plan: 601.001 [name].

The external surfaces of the development hereby permitted shall match those used in the existing building.

On 20 July 2021, the Government published a revised National Planning Policy Framework (the Framework). Other than a change to the relevant paragraph numbers, the revised Framework does not materially alter the national policy approach in respect of the issues raised in this appeal and therefore the main parties have not been prejudiced by its publication. I have determined the appeal on the basis of the revised Framework.

The main issue is whether the proposal would be inappropriate development in the Green Belt, having regard to the Framework and any relevant development plan policies.

The appeal property is a two-storey detached house located among other houses within the built-up part of the village. The site is nevertheless located within the Green Belt.

Paragraph 149 of the Framework states that the construction of new buildings should be regarded as inappropriate in the Green Belt, unless it falls within a number of listed exceptions. These include the extension or alteration of a building provided that it does not result in disproportionate additions over and above the size of the original building. Policy GS4 of the Harrogate District Local Plan (2020) (the LP) does not repeat the Framework exceptions, but identifies that applications for development in the Green Belt will be determined in accordance with national policy.

Neither the Framework nor Policy GS4 define what would constitute a disproportionate addition. [address] Extensions & Garages Design Guide Supplementary Planning Document (2005) refers to a ground floor area increase of the original house by 50%, but the Framework refers to ‘size’ rather than footprint. A 30% volume limit is also cited by the Council, but it is not clear where this arbitrary figure is derived from. I have therefore treated these thresholds as no more than a guide.

The evidence indicates that the house has already been extended from its original size. Figures provided suggest that the proposed extension, when taken with previous additions, would increase the size of the original building by around 135-136% in both floor area and volume. In purely mathematical terms this sounds potentially disproportionate, and far exceeds the guidance used by the Council. Indeed, in some circumstances, a percentage increase of this scale might be sufficient in itself to constitute a disproportionate addition over and above the size of an original building in the terms of the Framework.

That said, when determining whether or not a proposal would be a disproportionate addition, it is also important to consider the visual increase in the size of the original building, taking into account the nature of the site and the precise nature of the proposal. This is a matter of planning judgement for the decision maker.

In this instance, the proposal would infill a small corner at the back of the house. At just 4.7m2 in floor area and single storey height, it would be fair to describe the extension as modest, and represents only a small addition to the total floorspace and volume of the two-storey dwelling. Part of that increase would be a replacement of the existing lean-to shelter, which although of more lightweight and partly open construction, nevertheless has a physical presence in this position. Furthermore, there is no dispute that the extension would reflect the height, design, and materials of the small existing utility extension it would be attached to. It would also be set in from the main side elevation and would sit flush with the rear elevation. Thus, even when considered cumulatively with previous additions, the proposed extension would appear subservient and would integrate well with the existing building. In addition, due to its location at the rear, as well as the screening from surrounding garden vegetation and other buildings, the extension would not be readily visible from public viewpoints. Taking all these factors into account, it is my judgement that the proposed extension would not be a disproportionate addition over and above the size of the original building.

I therefore conclude that the proposal would not be inappropriate development in the Green Belt and to this extent it would not conflict with the Green Belt protection objectives of the Framework and LP Policy GS4. Where development is not inappropriate, it goes without saying that it would not be harmful to the openness of the Green Belt and would not conflict with any of the purposes for including land within it.

As suggested by the Council I have imposed the standard commencement and approved plans conditions for certainty. A condition requiring the external materials to match the existing building is necessary to ensure a satisfactory appearance of the development.

For the reasons given I conclude that the appeal should succeed.