Appeal 3350871

The appeal is dismissed.

A revised version of the National Planning Policy Framework (the Framework) was published on 12 December 2024. The content of the revised Framework has been considered but in light of the facts in this case it does not alter my conclusion.

The main issues are: • whether the proposed extension would be inappropriate development in the Green Belt having regard to the Framework and relevant development plan policies; • the effect on the character and appearance of the existing buildings and the surrounding area; 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 property is a two storey detached dwelling with a former agricultural barn next to it, within extensive grounds in a rural setting in the South Bedfordshire Green Belt. Permission exists for conversion of the barn to residential use and to create a single storey link extension between the two buildings1.

Policy SP4 of the Central Bedfordshire Local Plan 2015-2035 (2021) indicates that development proposals within the Green Belt will be assessed in accordance with guidance contained in the Framework. 1 [name]/22/01903/FULL.

The Framework states that an exception to inappropriate development in the Green Belt 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 2.

The Central Bedfordshire Design Guide indicates that, as a guiding principle, to be considered as proportionate the original building should not be added to by more than 60% of footprint, floorspace and volume3.

The Council states that the original dwelling was just under 78m2 floorspace, while previous additions and the proposed extension would result in floorspace of nearly 256m2. In terms of footprint, the original dwelling was just under 51m2 with the previous and proposed additions increasing this to just over 203m 2. These figures are not contested.

The previous and proposed additions to the original dwelling result in an increase of 228% in floorspace or a 301% increase in footprint. Consequently, these increases significantly exceed the 60% figure indicated as a guiding principle. By any reasonable assessment these additions clearly represent a disproportionate increase over and above the size of the original building, judged against the Framework, Policy SP4 and supporting guidance. As such, I conclude that the proposal would be inappropriate development in the Green Belt.

The proposed extension would inevitably reduce the openness of the Green Belt in this location to some extent. However, the overall effects both spatially and visually would be limited due to the extension’s single storey height and limited forward projection. For these reasons, the effect on the Green Belt’s openness would not be harmful.

Policy HQ1 of the Local Plan requires that all developments are of the highest possible quality and respond positively to their context. The policy also says that all new development will be expected to have regard to the [name]. The Guide says that the success of an extension will generally be determined by its relationship to the style, character, and appearance of the existing property. The existing building should not be dominated by the bulk, volume or character of the extension as the character of the existing building could be lost4.

The existing two buildings are modest in size and timber clad, reflecting the rural setting. The approved link is limited in scale and height, in effect providing a single storey corridor connecting the two buildings.

The proposed extension would be single storey with a flat roof and would not extend beyond the width of the existing buildings. Combined with its limited forward projection, these features mean that it would be subordinate in scale to the existing buildings. However, almost the full extent of the new frontage would be comprised of full-height glazing. This would introduce an excessive degree of glazing to the prominent front elevation, which would detract unfavourably from the existing timber clad buildings. Consequently, this would harmfully undermine the character and appearance of the existing buildings. 2 Paragraph 154c). 3 Paragraph 11.32.3. 4 Paragraph 11.21.1.

The appeal buildings are in an open rural setting on elevated land that is readily seen from the road frontage. The extent of the reflective glazing would be apparent in views of the extended building and particularly at night where internal lighting is likely to make the building much less discreet and more obtrusive in its appearance than at present. I note in this regard that Policy HQ1 includes a criterion to ensure that any lighting associated with the development does not have a detrimental impact on the surrounding area.

Accordingly, for these reasons, I conclude that the proposed extension would have an unacceptably harmful effect on the character and appearance of the existing buildings and the surrounding area. The proposal is, therefore, contrary to Policy HQ1 of the Central Bedfordshire Local Plan 2015-2035, as described.

I have had regard to the fact that the proposal is intended to create additional living space and that it would be designed and built in an environmentally sustainable manner. These considerations can be given moderate weight. The fact that there were no objections to the proposal from interested parties cannot weigh in its favour, but rather is a neutral factor.

The proposal would represent inappropriate development, which is, by definition, harmful to the Green Belt. The Framework requires that substantial weight should be given to any harm to the Green Belt. It would also have an unacceptably harmful effect on the character and appearance of the existing buildings and the surrounding area.

The other considerations raised in support of the development do not outweigh the harm identified to the Green Belt and the other harm. Therefore, very special circumstances do not exist.

The proposed extension is contrary to the development plan and to the Framework, and there are no other considerations that outweigh this conflict. Accordingly, for the reasons given, it is concluded that the appeal should be dismissed.