Appeal 3324346

The appeal is dismissed.

The description in the banner heading above is taken from the planning application form, however I have removed the superfluous words that are not acts of development.

Since the appeal was lodged, a revised National Planning Policy Framework (the Framework) has been published. This has not raised any new matters which are determinative to the outcome of this appeal.

The main issues are: • whether the development would be inappropriate development in the Green Belt having regard to the Framework and any relevant development plan policies; • the effect of the 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 proposal.

The appeal site lies within the Metropolitan Green Belt. The Framework identifies that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. It goes on to state that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. The Framework further establishes that the construction of new buildings in the Green Belt should be regarded as inappropriate, subject to a number of exceptions as set out in paragraph 154. One such exception being 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 S4 of the Vale of Aylesbury Local Plan adopted 2021 (VALP) seeks to protect land within the Green Belt from inappropriate development in accordance with national policy. It sets out types of small-scale development that will be supported, providing they preserve the openness of the Green Belt, and do not conflict with the purposes of including land within it. Extensions to buildings that are not out of proportion with the original building, normally no more than 25-30% volume increase of the original building, is one of those listed.

The Framework does not provide a definition of ‘disproportionate additions’ and therefore an assessment of whether a proposal would amount to a disproportionate addition over and above the size of the original building is a matter of planning judgement. The reference to ‘size’ can incorporate volume, height, external dimensions, footprint or visual perception.

The appeal proposal seeks to extend the existing 2 storey detached dwelling with 2 storey extensions to either side and a single storey extension to the rear, together with the demolition of the existing single storey detached garage to the rear of the property. The property has been previously extended. The volume of the earlier extensions, in addition to those now proposed, would amount to an increase in volume of 104% over and above the original building.

The property benefits from an extant permission1 for the demolition of the existing 2 storey rear extension and detached garage and the erection of 2 two storey side extensions and a single storey rear extension. The appeal proposal differs in that it includes the retention of the existing 2 storey extension to the rear of the property and a larger single storey rear extension in lieu of that previously proposed, to provide a new kitchen and dining/garden room.

The proposed 2 storey side extensions would be sympathetic in design terms to the host dwelling. Whilst visible from the highway to the front of the property, despite their height, the width of the extensions mean that they would not appear as an unduly dominant feature. Moreover, the proposal in that regard would maintain a degree of separation between the flank elevations of the dwelling and the adjoining residential properties so as not to undermine the established settlement pattern and spacious character of the area.

The proposed flat roof rear extension would be single storey and would extend only marginally beyond the previously approved single storey rear extension. It would also project significantly less distance from the rear of the dwelling than the existing detached garage which is to be demolished. The design of the extension would not be at odds with the main dwelling, and it would be viewed against the backdrop of the adjoining residential development and would not occupy an unduly visibly prominent position. 1 [name]. 21/04917/APP

Despite this, the extension, which would extend the entire width of the rear elevation of the original building, and the extension to one side, would comprise a significant footprint, built form and volume. Even considering the loss of the garage and its associated volume, the appeal proposal would nevertheless add significantly to the footprint, bulk and mass of the original dwelling. Therefore, having regard to the increase in floor area as well as the overall scale and volume of the proposed extensions, the development, when assessed cumulatively, and in combination with previous extensions, would result in disproportionate additions that would be well in excess of the size of the original dwelling. It would therefore significantly exceed the threshold set in VALP Policy S4.

For these reasons, the appeal proposal would constitute inappropriate development in the Green Belt which is, by definition, harmful. It would therefore conflict with Policy S4 of the VALP, and the provisions of the Framework.

Openness is an essential characteristic of the Green Belt that has spatial as well as visual aspects. The combination of the individual elements of the appeal proposals, would further increase the footprint, volume and massing of the original building. This would be particularly apparent through the significant extension to the footprint of the dwelling to the rear of the property, albeit this would be limited given the height of the rear extension.

Although the proposed rear extension would not project as far from the rear elevation of the property as the existing garage, the demolition of which could be secured by condition, it would be materially larger. Consequently, it would have a greater impact and would result in a harmful loss of openness of the Green Belt in spatial terms.

Having regard to the visual aspect to openness, due to the height and siting of the rear extension it would not be visually prominent, including in views from the open countryside to the rear. Whist the proposed side extensions would be more readily visible from the highway given their position on the site, due to their overall scale and the retention of the gaps between the dwellings, they would have a limited effect on the openness of the Green Belt in visual terms.

For these reasons in both spatial and visual terms the proposed development would have a greater impact on the openness of the Green Belt than the existing development. Furthermore, the proposal would conflict with the purposes of including land within the Green Belt, in particular to assist in safeguarding the countryside from encroachment, and the fundamental aim of Green Belt policy to prevent urban sprawl by keeping land permanently open.

Although limited, the proposal would nevertheless result in harm to the openness of the Green Belt. In accordance with paragraph 153 of the Framework substantial weight is given to any harm to the Green Belt.

A certificate of lawfulness (LDC) dated 5 January 2023 certifies that the erection of 2 outbuildings, a small artist studio and a larger outbuilding comprising a study/gym, would represent permitted development. However, the development has not yet been carried out.

The appellant has indicated that, particularly in the absence of the extended kitchen sought now, the outbuildings would serve as a very useful part of their accommodation, so there is a reasonable likelihood that they would be carried out if the appeal were dismissed. I note the appellants contention that the larger of the proposed outbuildings, which would have a volume of 272m3, alongside the extant planning permission, would have a greater effect on the openness of the Green Belt, and conflict with the purposes of including land within it, than the appeal proposal.

However, while the extensions may reduce the appellants’ need for the outbuildings, there is no mechanism before me to prevent the outbuildings detailed in the LDC being implemented in addition to the appeal proposal. A planning condition removing permitted development rights would not come into effect until the appeal development were begun and the outbuildings could be constructed first. Furthermore, there is no evidence to suggest that should the appeal be allowed, it would reduce the likelihood of the certificate of lawfulness development being carried out. In fact, I note the appellants’ submissions that they would ideally like both the study/gym outbuilding as well as the kitchen extension. Accordingly, I cannot be certain that the outbuildings would not be built.

Thus, even though the proposal may be less harmful than the combined effect of all other development that could be carried out at the site, I give no weight to this suggested fallback as I am unable to ensure sufficient control over the site through any permission I may grant.

I acknowledge that the proposed extensions would offer benefits in terms of the residential accommodation. However, as such benefits in that regard would be to the personal benefit of the appellants, this would be of limited weight. The proposal would also be sympathetic in design terms to the host building and the character and appearance of the area, including the Chilterns Area of Outstanding Natural Beauty. However, these are neutral factors.

The appeal scheme would be inappropriate development in the Green Belt which is harmful by definition and should not be approved except in very special circumstances. The Framework confirms that such circumstances only exist where the harm by reason of inappropriateness and any other harm is clearly outweighed by other considerations. As well as harm by reason of inappropriateness, the development would cause harm through loss of openness of the Green Belt, which the Framework indicate should be given substantial weight.

Having had regard to all other matters, I conclude that there are no other considerations that would clearly outweigh the harm that would arise by reason of inappropriateness and harm to Green Belt openness. Consequently, the very special circumstances required to justify the proposal do not exist and as such it would conflict with Policy S4 of the VALP and the Framework.

For the forgoing reasons, the appeal is dismissed. [planning inspector] INSPECTOR