Appeal 3299785

The appeal is dismissed.

The site lies within the designated Green Belt. Accordingly, the main issues for consideration are:

Whether the proposal would be inappropriate development in the Green Belt having regard to the revised National Planning Policy Framework and any relevant development plan policies.

The effect on the openness of the Green Belt.

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 Government’s policy for new development in the Green Belt is set out in the National Planning Policy Framework 2021 (the Framework). The aim of that policy is to prevent urban sprawl by keeping land permanently open; the essential characteristics of Green Belts are their openness and their permanence.

The Framework sets out that the construction of new buildings should be regarded as inappropriate development in the Green Belt but in paragraph 149 lists a number of exceptions to that one of which, relevant to this case, is 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 Framework does not set out what would constitute a disproportionate extension. It is a matter therefore of planning judgement. The Council’s Supplementary Planning Document 4 – A Guide for [address] Extensions and Alterations 2012, advises that extensions which would increase the size of the dwelling to no more than 30% above the original floor space would not normally have an undue impact because of its limited extent.

[site address] is a detached house occupying a corner plot within a cul-de-sac of properties which appear to have been built around a similar time. It has been previously extended following permissions for development in 1997 and

Permission is now sought for the demolition of the existing upvc framed conservatory, itself an extension, and its replacement with a structure of a more solid construction to form a larger kitchen/dining room. That structure would be wider and of greater volume and massing than the existing conservatory.

In this case there is no dispute between the parties that the cumulative size of the previous and proposed extensions is substantial. The Council calculate that the proposed development, in addition to that already undertaken, would result in a 111% increase in floorspace over that of the original dwelling, significantly more than the threshold set out in the SPD. Accordingly, although the appellant calculates that the increase in floorspace now proposed represents a further increase of 9%, and is therefore modest in itself, the proposed extension in addition to previous extensions would result in a disproportionate addition over and above the size of the original dwelling, which is the test of the Framework.

I note from all I have seen and read that other dwellings within [address] have been extended, although there are no details of those extensions and their sizes, or the circumstances in which they were approved, before me. Nevertheless, the existing extensions at No 12 are readily apparent and the building is visually more substantial than it originally would have been. Whilst the extension would replace the existing, visually lightweight conservatory, it would have a different form, size and massing and would clearly be read as a further addition to the property.

Therefore, considering proportionality based on either a mathematical calculation or an assessment of its visual impact, the result is that the cumulative impact of the additions to the property are disproportionate to the original dwelling.

On that basis the proposal would not fall within one of the exceptions set out in paragraph 149 and accordingly it constitutes inappropriate development. Inappropriate development, the Framework explains is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. I will turn to this matter later.

As set out above, openness is an essential characteristic of the Green Belt. In that the bulk of the building would be increased by additional built development, the proposal would reduce the openness of the Green Belt.

However, there is already a building on site and the proposed increase in terms of additional floorspace and volume is limited in spatial terms over what presently exists. In visual terms the property is well screened at the rear by high, dense boundary hedging which encloses the site. In addition, given the presence of the sizeable buildings of [name] sited immediately to the rear, the fact that the site is surrounded by built development rather than in an isolated position in the open countryside and considering the extent of the Green Belt as a whole, the harm to openness from this proposal would be very limited.

The Council has raised no objection to the extension in terms of its impact on the character and appearance of the area. Given the alterations that have taken place over time, the dwellings on [address] vary in terms of their design and form. The enlarged dwelling would not be out of place in that context and, in addition, given its height and distance from the side boundaries of the plot, would not adversely affect the living conditions of neighbouring residents. These are neutral matters in my consideration and do not represent benefits of the proposal.

The proposal would result in the replacement of a upvc conservatory which is nearing the end of its life and there would be some limited visual benefit to the appearance of the property from its replacement. Given that the structure is not visible from the public realm such benefit attracts limited weight. The proposal would also be of benefit to the appellant in terms of providing enhanced living accommodation. However, such private benefit can also carry only limited weight.

I have noted that there may have been a difference in opinion regarding the acceptability of the proposal by Council officers. I also understand that an application for a Lawful Development Certificate to ascertain, in effect, whether the proposal required planning permission, was withdrawn following advice from the Council although the full reasons for this are not before me. Furthermore, I cannot be certain of the extent of development that could be undertaken as permitted development, if any, and therefore whether a ‘fallback’ position exists in this case. I have sympathy with the appellant in terms of the lack of clarity these events may have caused. Nevertheless, these matters have no bearing on my consideration of the case which I can only consider on the basis of the evidence before me.

[name] have found that the proposal would have a very limited effect on the openness of the Green Belt it would be inappropriate by definition and would cause some harm to the Green Belt. The Framework is clear that substantial weight is given to any harm to the Green Belt. On the other side of the balance, the considerations advanced in support of the proposal individually and cumulatively carry moderate weight.

On that basis the very special circumstances needed to justify the proposal have not been demonstrated. As such the proposal is contrary to the requirements of the Framework and to Policy R4 of the [name] 2012, which seeks to preserve the Green Belt in accordance with national policy.

For these reasons and taking all other matters into account, the appeal is dismissed.