Appeal 3371105

The appeal is dismissed.

The main issues are: • Whether the proposal would constitute inappropriate development in the Green Belt having regard to the National Planning Policy Framework (the Framework) and any relevant development plan policies; • The effect on the openness of the Green Belt; and • Whether any 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 proposal.

The appeal site includes a detached dwelling (the existing dwelling), which the appellant proposes to extend. The site is in the Green Belt. The Framework states that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open, that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances, and that development in the Green Belt is inappropriate unless a listed exception applies.

Two such exceptions are set out at paragraph 154(c) and (g). The former supports 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. The latter supports limited infilling or the partial or complete redevelopment of previously developed land (PDL) which would not cause substantial harm to the openness of the Green Belt [my emphasis].

The Framework does not define ‘disproportionate additions’, leaving whether any particular proposal would amount to one as a matter of planning judgement. It does, however, define an original building as being one as it existed on 1 July 1948 or, if constructed after that, as it was built originally. PDL is defined as land which has been lawfully developed and is or was occupied by a permanent structure and any fixed surface infrastructure associated with it, including the curtilage of the developed land. It excludes land in built-up areas such as residential gardens.

For the purposes of this appeal, Policy GB1 of the [name] and Development Management Plan (2015) (the ADMP) adheres to Framework paragraph 154(c) insofar as it requires extensions to dwellings in the Green Belt to be proportional and subservient to the original dwelling, and to not materially harm Green Belt openness. It also requires evidence that the total floorspace of any proposed extension, when considered along with any previous extensions, alterations, and outbuildings, would not result in an increase of more than 50% above that of the original dwelling. Whilst this is a level of specificity not contained in the Framework, I see no reason to view it as inconsistent with its aims.

The supplementary planning document ‘Development in the Green Belt’ (2015) (the SPD) sets out the Council's approach to PDL. It is based on an older version of the Framework, and captures an expectation that proposed development have no greater impact on the openness of the Green Belt. The SPD also expects development not to occupy a larger area of the site than existing buildings, which is not a feature of paragraph 154(g).

The appellant has made a detailed argument that the dwelling originally had a floor space of some 116m2, to which a two-storey side extension added a further 48m2, an increase of some 42%. On the basis of these figures, the appeal scheme would result in an overall increase in floor space of some 88% compared to the original dwelling. This would be a significant breach of the 50% threshold in Policy GB1, achieved by two, two-story additions to what was a reasonably modest dwelling, the footprint of which would be extended significantly in two separate directions. Overall, these features would combine to result in a significant increase in the size of the original building, and a disproportionate addition. As such, the appeal scheme does not have the support of Framework paragraph 154(c).

There is no suggestion that the appeal site has been unlawfully developed, or that the existing dwelling is anything other than a permanent structure. The appeal scheme extension would be erected within the curtilage of the dwelling, which I see no reason to describe as being in a built-up area. Given this, the location of the proposed development is PDL. The appellant contends that, accordingly, the appeal scheme benefits from the exemption at paragraph 154(g), subject to it not causing substantial harm to Green Belt openness.

In order for that to be so, however, the appeal scheme must comprise either limited infilling, or the partial or complete redevelopment of the land. The term infilling is not defined, but to my mind would involve filling a gap between two things, which the appeal scheme would not. I do not see that an extension, added to an existing building which will remain largely unchanged, on a site which will also remain largely unchanged, may sensibly or reasonably be described as even the partial redevelopment of the land in the context of paragraph 154, given that the extension or alteration of a building is already recognised as a distinct type of development in a separate subsection of that same paragraph.

My attention has been drawn to a recent decision by the Council at Kenlume1, a dwelling near the appeal site. Here, a replacement side extension which increased the original floor space by some 80% was found to be disproportionate, but to benefit from paragraph 154(g) as it was located on PDL and replaced some existing structures. On the evidence before me, the significance of the existing structures is not clear, as the extension was to be built on PDL in any event. The rationale behind the different decisions is not one I can speak to, therefore. Ultimately, I must apply the relevant policies to the proposal before me.

Given all of the above, even if the appeal scheme would not cause substantial harm to the openness of the Green Belt it nevertheless does not benefit from the support of Framework paragraph 154(g). The appeal scheme would be inappropriate development in the Green Belt, and conflict with Policy GB1 of the ADMP and with the Framework.

Openness is an essential characteristic of the Green Belt that has spatial as well as visual aspects. The appeal scheme would include additional built form where it did not previously exist and, as such, would have a spatial effect on openness. It would add a two-storey addition to the dwelling, introducing development to a space which is currently open. The site is quite secluded and direct visibility of the appeal scheme development would be limited from the public realm. Even so, the extension would be visible from neighbouring homes and from within the appeal site, from which it would be prominent. It would therefore have a visual effect on openness.

The Council has found that the appeal scheme would not harm visual amenity or the character and appearance of the area, including the High Weald National Landscape (NL). The appellant contends that if not for the restrictions imposed by the location of the site within the NL, a comparable scheme could be erected using permitted development rights.

I see no reason to take a different view to the Council regarding the effect of the appeal scheme on visual amenity, including that of the area and the NL. I also appreciate that the General Permitted Development Order (GPDO) is, as per the technical guidance for householders, intended to “allow householders to improve and extend their homes without the need to apply for planning permission where that would be out of proportion with the impact of works carried out”.

Even so, there is nothing in the Framework to indicate that extensions which are acceptable in terms of visual amenity and/or are of a type generally approved by the GPDO are also therefore proportionate to the original building in terms of size. I have set out above why I find the extension to be disproportionate. Overall, the appeal scheme being possibly comparable to one the GPDO would allow in other Green Belt settings does not alter my findings in that respect, nor comprise a very special circumstance. 1 Application Ref 25/00553/HOUSE

My attention has been drawn to two previous appeals2. Regarding the first of these, I see no reason to doubt that some schemes which result in Green Belt buildings being increased by more than 50% may be considered proportionate. That, however, is an assessment to be undertaken on a case-by-case basis. I see little in the first previous appeal to suggest that the outbuilding in question resulted in anything close to an 88% increase, as is the case with the appeal scheme before me which, as set out above, I have found to have a harmful effect on openness partly by virtue of its height. The outbuilding in the previous appeal, in contrast, was described as having a low profile. Overall, the two schemes do not appear directly comparable, leading me to attach little weight to the first previous appeal.

Whether the development subject of the second appeal was found not to result in a materially greater impact on openness and therefore not amount to inappropriate development under Framework paragraph 154(g) carries very little weight in my determination, as I have found the appeal scheme before me not to comprise a form of development described by that sub-paragraph. The effect on openness does not, therefore, stand to be considered.

The appellant cites the prospect that a single storey extension to the dwelling may be erected by virtue of the GPDO. On the evidence before me, the possibility of that lawful scheme taking place is greater than theoretical. That said, the weight I attribute to the fallback position that it offers is minimal, as it would have a lesser impact on the openness of the Green Belt than the appeal scheme.

The proposal would constitute inappropriate development in the Green Belt and would harm openness. As such, the Framework requires that the harm by reason of inappropriateness be given substantial weight, and that inappropriate development should not be approved except in very special circumstances. Very special circumstances will not exist unless the harm to the Green Belt and any other harm is clearly outweighed by other considerations.

The other considerations in this case are not sufficient to comprise the very special circumstances necessary to justify the development, which is contrary to Policy GB1 of the ADMP and to the Framework, which seeks to protect the Green Belt.

I have considered all other matters raised but none outweigh the conclusions I have reached. The proposal conflicts with the development plan overall and the material considerations do not indicate that the appeal should be decided other than in accordance with it. The appeal is therefore dismissed.