Appeal 3334894

The appeal is dismissed.

The appellant advises that the appeal property is known as ‘[name] rather than ‘Longheath’ as originally detailed on the application forms. This is reflected in the above banner heading.

The National Planning Policy Framework (the Framework) was revised in December 2023. As the changes do not materially affect the main issues in this case, the parties have not been invited to make further comments. Where reference is made to the Framework in this decision, the paragraph numbers are those that appear in the latest version.

The main issues are: • whether or not the proposed development constitutes inappropriate development in the Green Belt; • its effect on the openness of the Green Belt; • whether any harm by reason of inappropriateness, if found, and any other harm, would be clearly outweighed by other considerations so as to amount to the very special circumstances required to justify the development.

The appeal site comprises a detached two storey dwelling, with a detached garage to the side. The proposal is for the garage to be attached to the existing dwelling, with a new roof form above. The proposed single storey rear extension would extend across the full width of the existing dwelling and the attached garage.

The site is in the Green Belt. The Framework states that the construction of new buildings should be regarded as inappropriate in the Green Belt. This is subject to the exceptions listed in the Framework, which include at paragraph 154 (c) ‘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 define what constitutes ‘disproportionate additions’, although it defines the date of an ‘original building’ as it existed on 1 July 1948, or, as originally built if constructed after that date.

Policy CS6 of the [name] (2012) (CS) and Policy DM13 of the Development Management Policies Development Plan Document (2016) ([name]) set out similar provisions and are broadly consistent with the Framework. Although the supporting text of Policy DM13 explains how the Council will assess such proposals, indicating that a comparison will be made between the size of the ‘original’ building with the proposed extension taking account of siting, floorspace, bulk and height. It further states that whilst any application will be judged on its own individual merits, the general expectation is that to be acceptable, proposals will be within the range of 20-40% above the original volume of the building. Although not necessarily determinative, and volume is only one factor in assessing a proposal, I have had regard to this and all other relevant facets of the appeal scheme in making my assessment.

The existing dwelling has been extended previously. It is common ground between the parties that the ‘original’ dwelling had a footprint of approximately 79sqm and a floor area of 136sqm. There is also no dispute that the proposed extension, in combination with the previously implemented extensions to the dwelling would represent an uplift over the ‘original’ dwelling by about 159% footprint, 176% floor area and 102% volume.

The proposed rear extension would extend across the entire width of the dwelling and the adjacent garage which would be attached to the dwelling. This, together with its considerable depth and height, would result in very significant increases to the footprint, scale, bulk and massing of the dwelling. The proposed alterations to the roof of the garage would also add to the scale and bulk of the proposal. Furthermore, the resultant increase in volume to the ‘original’ dwelling would significantly exceed the 20-40% range set out in the supporting text to Policy DM13 of the [name]. I therefore find that the proposed development, in combination with previous extensions, would result in disproportionate additions over and above the size of the original building.

To that end, the proposal would not meet the exception outlined at paragraph 154 c) of the Framework and Policy DM13 of the [name]. Consequently, the proposal would be inappropriate development in the Green Belt.

The Framework emphasises that a fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open; the essential characteristics of Green Belts are their openness and their permanence. Openness has spatial as well as visual aspects.

The proposal would result in a significantly increased built mass and scale of development above and between the garage and extending a considerable distance to the rear of the building, beyond its existing spatial extents. Accordingly, it would have a marked adverse effect on the spatial aspect of openness, thus resulting in harm to the Green Belt.

The proposed alterations to the garage, including the infilling of the gap between it and the existing dwelling and the alterations to its roof form would be visible from [address]. Whilst there would be an increase in built form, most notably due to the increase in the scale and bulk of the new roof, views of it from [address] would be filtered by the existing coniferous and deciduous trees and shrubs. Accordingly, the visual harm to the openness of the Green Belt arising from the alterations to the garage would be limited.

The proposed single storey rear extension would be well contained within the site with well screened side boundaries and trees to the rear, limiting external views to those from the adjacent dwellings either side which similarly sit within spacious, well landscaped plots. Therefore, the rear extension would result in limited visual harm to the openness of the Green Belt.

The appellant has referred me to two Lawful Development Certificates (LDCs) that have been issued in respect of the site. These relate to an 8 metre deep single storey rear extension1 (LDC issued in July 2022) and a single storey side extension following removal of existing detached garage2, issued in October

These extensions have not been implemented but the appellant states that the appeal proposal is essentially an amalgamation of the two extensions.

I acknowledge that there is a reasonable likelihood that the developments referred to in the LDCs would be implemented in the event that this appeal were to fail. The proposed extension would not extend as deep into the site as the single storey rear extension confirmed as lawful in the LDC. However, the proposed extension would also spread across the full width of the dwelling and the attached garage, resulting in a considerable increase in the spread of development and built form. Overall, the appeal proposal would be likely to result in additional footprint, floorspace and volume compared to the LDC extensions and consequently, would have a more harmful effect on the Green Belt than the potential ‘fall-back’ position. I therefore afford moderate weight to this consideration.

The appellant also states that an outbuilding could be constructed in the rear garden of the dwelling under permitted development rights3. However, no such certificate of lawfulness has been obtained and there are no plans before me suggesting a scheme would be readily built out in the event the appeal were to fail. In any event, an outbuilding would constitute a different form of development to the appeal proposal. I therefore place limited weight on this consideration.

The appellant has provided examples of other large extensions to dwellings in the Green Belt, notably at Foxcote and The Copse also on [address]. However, precise details and circumstances of these extensions were not 1 LPA ref. PLAN/2022/0104 2 LPA ref. PLAN/2022/0874 3 The Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) provided and I am unable to make accurate comparisons with the circumstances of the appeal proposal. Moreover, the Council state that the extensions at Foxcote (LPA ref. PLAN/2021/0293) involved demolition and explain that ‘very special circumstances’ were found to apply. In any event, I am required to determine the appeal on its own merits.

Other than on Green Belt grounds there are no objections to the proposed extension. However, the absence of harm in other respects is not a positive consideration, as acceptability in design and amenity terms is to be expected by the policies. These are therefore neutral matters in the overall planning balance.

The proposal would be inappropriate development in the Green Belt. Inappropriate development is, by definition, harmful to the Green Belt. In addition, I have found harm to the openness of the Green Belt. In accordance with paragraph 153 of the Framework, I attach substantial weight to harm to the Green Belt. The other considerations combined provide moderate support for the proposal. These do not, therefore, clearly outweigh the totality of harm and so very special circumstances do not exist. Therefore, the proposed development conflicts with Policy CS6 of the CS, Policy DM13 of the [name] and paragraphs 152 and 153 of the Framework, because there are no very special circumstances advanced which outweigh the harm to the Green Belt.

I have found that the proposal conflicts with the development plan taken as a whole, and the National Planning Policy Framework, and there are no other material considerations advanced to outweigh that finding. Therefore, for the reasons given above, I conclude that the appeal should be dismissed.