Appeal 3303222

The appeal is dismissed.

The Council has submitted the Pre-Submission Spelthorne Local Plan: 2022 – 2037 for examination to the Secretary of State, as of December 2022. I have little information to suggest when the plan is likely to be adopted, or if any policies have been modified, or if there are any unresolved objections. Accordingly, I attribute limited weight to this plan.

The main issues are: • Whether the development would be inappropriate development in the Green Belt having regard to the National Planning Policy Framework 2021 (the Framework) and any relevant development plan policies; • The effect of the development on the openness of the Green Belt; • The effect of the development on the character and appearance of the 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 Framework states that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. Saved Policy GB1 of the Spelthorne Borough Local Plan, adopted April 2001 (SLP) is broadly consistent with the approach of the Framework, in that there is a presumption against proposals which conflict with the purposes of the Green Belt and maintaining its openness.

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 149. Criterion d) of paragraph 149 has been cited by the appellant in regard to this appeal, however this relates to the replacement of a building, and given the appeal scheme is for a roof extension to the existing property this exemption would not apply.

Nevertheless, criterion c) of paragraph 149 would be applicable as this exception applies to 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 EN2 of the Spelthorne Borough Council Core Strategy and Policies Development Plan Document, adopted February 2009 (SCS) among other things, also refers to extensions being permitted where they do not significantly change the scale of the original building.

The appeal site consists of a single storey detached dwellinghouse located on the eastern side of the river Thames, which has been extended over time including two single storey side extensions and a single storey rear extension. The appeal proposal is to provide a roof extension to create additional accommodation within the roof space. There is no dispute between the parties that there will be an increase in the built form as a result of the appeal proposal. The Council highlights that in terms of size, the appeal scheme combined with the existing extensions would cumulatively increase the overall footprint of the original building by approximately 105%, with the increase in height of the proposal approximately 2.3 metres (m) above the original dwelling.

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 Council refer to a 30% increase being acceptable and proportionate, however this figure is unsubstantiated in either policy or supplementary planning guidance.

The appeal proposal would see the existing single storey dwelling extended to provide additional accommodation in the roof space. To facilitate this, the front and rear elevations would be built up, albeit set in from the eaves, and a new roof erected with a higher ridge line, increased by 2.3m to accommodate the additional rooms. Whilst the proposal itself, would not increase the footprint of the property, it would increase its volume, with parties estimating the cumulative volume increase to be approximately 173% over that of the original building. Taken together, these increases would amount to substantial additions to the property, and one which I find to be disproportionate over and above the size of the original building.

Accordingly, the appeal scheme would be inappropriate development in the Green Belt, which, by definition is harmful. The proposal would therefore conflict with the Framework and SLP Policy GB1 and SCS Policy EN2. Paragraph 148 of The Framework instructs that substantial weight should be given to any harm to the Green Belt, and that ‘very special circumstances’ will not exist unless the potential harm to the Green Belt by reason of inappropriateness, and any other harm resulting from the proposal, is clearly outweighed by other considerations.

There are spatial and visual aspects to the assessment of the openness of the Green Belt. In spatial terms, while the appeal proposal would not increase the footprint of the existing development at the site, the extension would increase the development size in terms of height, and therefore would have an adverse impact on the openness of the Green Belt in spatial terms.

With regard to the visual aspect, the property is visible from public vantage points along [name] to the front and views from the river Thames at the rear. The increase in height and mass at the roof level would be clearly visible from the surrounding area and as such, would intrude upon the openness of it. Nevertheless, the site itself occupies a residential area which includes other two storey developments, like the adjoining property at No 55, which contrasts with the much less developed open space that surround the area. As such, given the variation I conclude in visual terms, the scheme would have no effect on the visual aspect of openness of the Green Belt.

Overall, whilst I find there would be no harm to the visual dimension of the openness of the Green Belt, there would be to the spatial dimension. Therefore, the proposal fails to preserve the openness of the Green Belt.

The character and appearance of [name] consists of a ribbon of development along the bank of the river Thames. The properties consist of generally detached dwellings in close proximity to one another, with a mixture of ridge heights, materials and finishes.

The proposed scheme provides a domestic feel and appearance and, in this context, would conform to the general pattern of development along [name] and would not appear out of place. Furthermore, in terms of the size and height, the proposals have had regard to the existing residential buildings in the area and would follow the general vernacular of development. Whilst providing an alternative more contemporary material finish, the proposal would not appear out of keeping. The materials are highlighted in the application documents but could be subject of a condition, to allow for further detailed design.

The proposal would not therefore harm the character and appearance of the surrounding area. As such, it would accord with the principles of SCS Policy EN1 and Spelthorne Borough Council Design of [name] and New Residential Development Supplementary Planning Document 2011, which amongst other things, require all new development to respect and make a positive contribution to the character in the surrounding area. Furthermore, I do not find conflict with SCS Policy EN2 in that this relates to the Green Belt issues referred to above. Given that I have found no harm to the character and appearance of the area, this would be a neutral factor in the planning balance.

I have been referred to a number of examples which the appellant considers show inconsistency in decision making by the Council 1. From the information I have been provided and from my own observations, it is acknowledged that there are similar extensions and increases in ridge heights, notably at Nos 5, 48 and 49. However, I have not been presented with the full details in respect to the history of these cases and whether or not the schemes were considered disproportional to the original dwelling. In any case, each scheme must be considered on its own merits. While consistency in decision making is important, ultimately, what constitutes an exception under Green Belt policy needs to be determined in the light of the specific circumstances and context of each case. I am not therefore persuaded that these examples are directly comparable to the proposal before me, and they do not alter my views.

The appellant refers to a fallback position with regard to permitted development rights and the current legislation on prior approvals in respect to larger extensions. The appellant further highlights that a condition removing these rights would be acceptable should permission be granted. However, I have been provided with no details of these alternative schemes and cannot therefore be sure that they would be a realistic or probable alternative. I therefore give limited weight to this as a fallback option.

I also acknowledge that as part of the evidence base of the local plan review, the Council has commissioned an assessment of the Green Belt2. The appeal site is located in Local Area 55 which was found to have a strong overall score in the Green Belt assessment, in that it met at least one of the purposes of Green Belt as stated in the Framework. The local plan review is at an early stage, and while the assessment of Green Belt is an important part of the evidence base, I have little information to suggest whether any designations and/or boundaries are likely to be altered, or whether any sites are likely to be removed from the Green Belt as a result. It does not therefore alter my views in relation to the main issues before me and I would afford this limited weight.

While the introduction of additional accommodation at the roof level would provide safe haven as the site is located in the flood zone, given the existing habitable rooms are already located at the ground floor, the current layout appears to be functional and sufficient to provide an adequately safe living environment for its occupants. Accordingly, I also give this matter limited weight.

The development plan and the Framework states that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. The Framework goes on to advise that substantial weight should be given to any harm to the Green Belt and that very special circumstances will not exist unless the potential harm to the Green Belt by reason of inappropriateness, and any other harm, is clearly outweighed by other considerations.

Although there are benefits weighing in favour of the proposal, in this particular case the other considerations put forward do not clearly outweigh the 1Spelthorne Borough Council Planning Refs: 06/00694/FUL, 13/00890/HOU and 14/01869/FUL 2 Spelthorne Borough Council Green Belt Assessment (Stage 1) Report: Methodology and Assessment prepared by ARUP dated February 2018 (Ref: 251368-05-04 [name]) substantial weight that I give to the harm to the Green Belt, by reason of inappropriateness and the harm to openness that I have identified. Consequently, the very special circumstances necessary to justify the development do not exist.

The development conflicts with the development plan taken as a whole and there are no material considerations to suggest the decision should be made other than in accordance with the development plan. Therefore, for the reasons given, and having had regard to all other relevant matters raised, the appeal is dismissed.