Appeal 3323565

The appeal is dismissed.

Since the appeal was lodged, a revised version of the National Planning Policy Framework (the Framework) was published (19 December 2023). This does not materially change the planning policy context in respect of the main issue.

The main issues are: • whether the proposed development would be inappropriate development in the Green Belt, having regard to the Framework and any relevant development plan policies; • if the proposed development is inappropriate, the effect of the proposed development on the openness of the Green Belt; and • whether the harm by reason of inappropriateness, and any other harm, would be clearly outweighed by other considerations so as to amount to the very special circumstances required to justify the proposed development.

The appeal site comprises a garden plot accommodating a two-storey dwelling and detached outbuildings.

National Green Belt policy in the Framework sets out that inappropriate development is, by definition, harmful to the Green Belt and should not be approved ‘except in very special circumstances.’ There are, however, certain exceptions. One of those, at paragraph 154, is the extension or alteration of a building, provided it does not result in disproportionate additions over and above the size of the original building. Policy GB1 of the South Bucks District Local Plan (LP, 1999) broadly conforms to the general thrust of national Green Belt policy, which in summary supports the limited extension of existing dwellings. The Framework does not provide a definition of ‘disproportionate additions.’ However, LP Policy GB10 sets out, in its supporting text, that extensions or alterations which would result in the original dwelling having increased its floorspace by more than half will not be regarded as ‘small scale’.

The Council indicates that the dwelling in its original form had a floor area of approximately 133sqm. It indicates that existing extensions amount to an increase in floorspace of approximately 170sqm (over 120% over the original floorspace). The proposed extension would add approximately 14.5sqm to the dwelling. The total added floorspace would therefore measure approximately 185sqm (over 130%).

The appellant does not dispute these figures, setting out that a series of extensions have taken place previously, including an additional storey. However, they argue that the previous extensions were approved under permitted development, and therefore these should not be included in any floorspace figure under LP Policy GB10. However, the supporting text to LP Policy GB10 clearly states that any extension which has been added to the original dwelling shall be taken as comprising increased floorspace, irrespective of whether it was permitted development or was constructed with the benefit of planning permission. I consider this to be an entirely reasonable approach.

On the ground, there is no garage or single-storey structure in the position of the proposed development. Any further increase in floorspace would, when combined with existing extensions, lead to a disproportionate addition over and above the size of the original building.

For the above reasons, the proposed developments would be inappropriate development in the Green Belt which is, by definition, harmful. The proposed developments would therefore conflict with the relevant provisions of [name] GB1 and GB10, which in summary seek to limit extensions to dwellings in the Green Belt. This is in a similar vein to the objectives of the Framework insofar as development in the Green Belt is concerned.

The Framework indicates that openness is an essential characteristic of the Green Belt, and a fundamental aim of Green Belt policy is to keep land permanently open. The openness of the Green Belt has both a physical and visual dimension. ‘Open’ can mean the absence of development in spatial terms, and it follows that openness can be harmed even when development is not readily visible from the public realm.

Notwithstanding the existence of other properties near the appeal site, intervening boundary features and landscaping across the site, the appeal property is visible from the adjacent highway and neighbouring properties. Nevertheless, the openness of the Green Belt is readily apparent beyond the appeal site.

[name] accept that the proposed development would form an extension to the dwelling which has been designed with some sensitivity to siting, prevailing building form, materials and detailing, it would nonetheless result in built volume and massing where this does not presently exist.

Even were the proposed development to replace an existing addition or structure, as illustrated on the submitted existing plans but which does not exist on site, it would be set forward of that illustrated building line, and would be taller than it. The additional bulk of the dwelling as a result of the proposed development, irrespective of a reliance on floorspace, would inevitably lead to a loss of openness, both physically and visually. Accordingly, the proposed development would cause harm to the openness of the Green Belt. This factor weighs somewhat against the proposal.

The Framework is clear that substantial weight should be given to any harm to the Green Belt. ‘Very special circumstances’ will not exist unless the potential harm to the Green Belt by reason of inappropriateness, and any other harm resulting from the development, is clearly outweighed by other considerations.

I accept that a structure, described as a garage and store, once existed in the position of the proposed extension. I also acknowledge that this had to be demolished for structural reasons. However, that structure does not currently exist and I have no substantive evidence before me to demonstrate its age, or illustrating its full extent. Accordingly, I cannot be certain that this element should be treated as original or a later addition. On this basis, I can only afford this matter limited weight.

I accept that the extension would have no proven impact on biodiversity or green infrastructure. Nevertheless, the lack of harm in this respect is neutral and I afford this matter no weight.

I acknowledge that no objection was received from the Parish Council. A lack of objection is neutral in my determination of the appeal and I afford this matter no weight.

I also acknowledge that a series of alterations and extensions have taken place along the wider street. However, I have no detail before me of the context of those extensions and alterations, including their planning history. Accordingly, I afford this matter no weight.

The Framework indicates that inappropriate development is, by definition, harmful to the Green Belt and should not be allowed except in very special circumstances. In addition, there are impacts on openness here. Substantial weight should be given to any harm to the Green Belt. Very special circumstances will not exist unless the harm to the Green Belt and any other harm is clearly outweighed by other considerations.

Cumulatively, I attach no more than limited weight to the benefits of the proposed development which make up the other considerations. As such, the other considerations do not clearly outweigh the harm to the Green Belt.

Consequently, the very special circumstances necessary to justify the proposed development do not exist. The proposed development would therefore be contrary to the relevant provisions of the Framework and the development plan as a whole. The appeal is dismissed.