Appeal 3269928

The appeal is dismissed.

In the interests of clarity, in the banner heading above I have referred to the description of development given by the appellant on the appeal form as this gives a clear description of the type of development proposed which reflects that used by the Council in their decision notice.

The main issues are: • whether the proposal would be inappropriate development in the Green Belt having regard to the National Planning Policy Framework and any relevant development plan policies, and the effect of the proposal on the openness of the Green Belt; and • if there would be harm by reason of inappropriateness, and any other harm, whether the harm would be clearly outweighed by other considerations to amount to the very special circumstances necessary to justify the proposal.

The appeal site is located within the Green Belt. Paragraph 149 of the National Planning Policy Framework (2021) (the Framework) states that construction of new buildings within the Green Belt is inappropriate development unless the development falls within specified exceptions. One such example listed 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. Policies GB1 and GB4 of the Royal Borough of Windsor and Maidenhead Local Plan ([name] in June 2003) (LP) broadly align with the Framework in this matter.

There is dispute between the parties over the cumulative increase in floorspace that would result from the proposed development. Nonetheless, the appellant’s own calculations indicate that the cumulative floorspace would be 112 sqm, an increase of 99.12% over that of the original building. Furthermore, the proposed development would increase the roof height and add dormer windows substantially altering the building’s appearance. I therefore find that the proposed changes would amount to disproportionate additions to the dwelling. It would accordingly amount to inappropriate development in the Green Belt, and I attach significant weight to the harm that would be caused.

Paragraph 137 of the Framework identifies the essential characteristics of the Green Belt as being its openness and permanence. [address] comprises a group of detached houses on one side of, and set back from, [site address] . The open countryside is visible on the road approaching the houses. Although trees line the opposite side of the road and screen views of the reservoir to the rear, the area retains a rural character.

House designs vary along the road, comprising mainly single storey bungalows with some 2 storey houses. Although the houses largely obscure views of the countryside behind them, gaps between them allow glimpses of trees to the rear. Several houses have roof alterations with front dormer windows, including a neighbouring house.

The proposed extension would increase the roof height and bulk but still afford views of trees to the rear and, in the context of the varied roof forms and heights of nearby dwellings, the effect on openness in the Green Belt would be minimal.

I conclude overall that the proposed development would represent a disproportionate addition over and above the size of the original dwelling and as such would be inappropriate development within the Green Belt. Its harm to openness would be minimal. Nonetheless, the proposed development would be contrary to policies GB1 and GB4 of the LP which only allow residential extensions in the Green Belt that would not cause a disproportionate addition. The decision notice refers to policy NP/OE4 of the Horton and Wraysbury Neighbourhood Plan (2018 to 2033) which identifies green spaces where new development is restricted. The appeal site is not within an identified green space and as such the policy is not relevant to the proposal.

I have considered matters in support of the application including the Council’s view that the proposal would not harm the character and appearance of the dwelling or street scene and would be acceptable in terms of its impact on highways safety, trees, parking, and the living conditions of neighbours. However, I do not consider that the absence of harm would amount to the very special circumstances necessary to justify the proposal.

The appellant has referred to his permitted development rights as a potential fall-back position that should outweigh the harm to the Green Belt. I have no details of an alternative scheme demonstrating that it would be similar to, or more harmful than, the current proposal, or evidence that it would be developed in the event of this appeal being dismissed. As such, it is a matter of negligible weight.

I find that the proposal would be inappropriate development in the Green Belt. In line with the Framework, I afford substantial weight to the harm caused by reason of inappropriateness. The other considerations described above do not clearly outweigh the totality of the harm I have identified. Accordingly, the very special circumstances necessary to outweigh this harm do not exist.

I therefore conclude that the appeal should be dismissed.