Demolition of outbuildings, existing rear dormer window and part of existing single storey rear extension and erection of a single storey rear extension

Appeal Decision Site visit made on 12 March 2020 by M Seaton DipTP MRTPI an Inspector appointed by the Secretary of State for Communities and Local Government Decision date: 1 June 2020 Appeal Ref: APP/G2245/D/19/3243221 Thornlea, The Grove, West Kingsdown, Kent, TN15 6JJ • The appeal is made under section 78 of the Town and Country Planning Act 1990 against a refusal to grant planning permission. • The appeal is made by Mr Ben Vallins against the decision of Sevenoaks District Council. • The application Ref 19/02570/HOUSE, dated 3 September 2019, was refused by notice dated 1 November 2019. • The development proposed is the demolition of outbuildings, existing rear dormer window and part of existing single storey rear extension and erection of a single storey rear extension. Decision 1. The appeal is dismissed. Main Issues 2. The main issues are: • whether the proposed development would amount to inappropriate development for the purposes of the National Planning Policy Framework (the Framework) and development plan policy; • the effect on the openness of the Green Belt and the purposes of including land within it; • if the development is deemed inappropriate, whether the harm to the Green Belt by reason of inappropriateness, and any other harm, would be clearly outweighed by other considerations so as to amount to the very special circumstances necessary to justify the development. Reasons 3. The appeal site is occupied by a detached bungalow which has been previously extended to the rear and at first floor level to provide additional accommodation within the roof space. 4. The property is set on the southern side of The Grove, which is a private residential drive, and comprises a long plot with woodland beyond. There are several outbuildings also located within the curtilage adjacent to the boundary with the neighbouring residential property at Woods End. 5. In addition to being located within the Metropolitan Green Belt, the appeal site is also within an Area of Outstanding Natural Beauty (AONB). Appeal Decision APP/G2245/D/19/3243221 2 Whether inappropriate development 6. Paragraphs 143-145 of the Framework state that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. Substantial weight should be given to any harm to the Green Belt and “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. However, this is subject to a number of exceptions which are as set out at paragraph 145 and includes at paragraph 145(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. 7. In determining the planning application, the Council has referred me to Policy GB1 of the Sevenoaks Allocations and Development Management Plan, February 2015 (the Local Plan), which addresses the matter of limited extensions to dwellings in the Green Belt. 8. The policy sets out the expectation that for an extension to a dwelling in the Green Belt to be permitted, the dwelling must be (a) lawful and permanent in nature, and (b) any extensions must respond to the original form and appearance of the building, with the volume of any extension remaining proportional and subservient to the ‘original’ dwelling. Furthermore, the extension must not materially harm the openness of the Green Belt through excessive scale, bulk or visual intrusion. I have also had regard to the Council’s assessment of the proposed development against criterion (c) that sets out that the accumulation of extensions, alterations and outbuildings within 5m, should not result in an increase of more than 50% above the floorspace of the original dwelling. 9. On the basis of my observations the existing dwelling is clearly permanent in nature and there is no evidence before me to suggest that it is not a lawful development. However, in assessing the proposal against criterion (b), it is important to first understand and define the extent of the ‘original dwelling’. 10. The text attached to Policy GB1 defines ‘original dwelling’ as meaning that which existed on 1 July 1948, and if no dwelling existed on that date then it is defined as the dwelling as first built after 1 July 1948. The definition of ‘original’ is consistent with that contained within the Glossary at Annex 2 of the Framework in seeking to define an ‘original building’. 11. The appellant indicates that the original dwelling was constructed in 1936 and the parties have agreed that this comprised a dwelling of 77.8m2. The Council has undertaken an assessment of the uplift of the existing extensions and the closest outbuilding, which is within 5 metres of the existing dwelling and is treated therefore as an extension. The uplift amounts to an additional 47.29m2 or 61%. The total area of the resultant dwelling including the new proposed extension and floorspace would be 190.01m2, or an increase of approximately 144%. 12. I note the Council has also included some further volumetric calculations. Whilst I have not been provided with the volume of the original dwelling, the existing house including extensions and the outbuilding is indicated to total 374.28m3. However, the total volume of the proposed scheme would be Appeal Decision APP/G2245/D/19/3243221 3 602.98m3, an increase of 228.7m3, or 61%, which would clearly be greater still if the volume of existing extensions and the outbuilding was included. 13. I have had regard to the disagreement between the parties as to whether the first-floor accommodation should be included within the calculations and the associated wording of the policy. In this regard, it would seem that the extensions as implemented resulted in a change to the roof form and the proposed development does not result in a reversion to the original roof form of the dwelling, and therefore it must be reasonable to include this floorspace in the calculations. 14. Nevertheless, and irrespective of whether this floorspace is included, by either area or volume the resultant dwelling would still comprise a significant uplift in size from the original dwelling. In the context of an assessment against Policy GB1 and paragraph 145(c) of the Framework, I am satisfied the proposed development would result in a disproportionately large series of additions which would not be subservient to the original dwelling. Even setting aside matters related to design and openness, the latter which I address below, the proposed development would neither accord with Policy GB1 of the Local Plan, or paragraph 145(c) of the Framework, and would therefore be considered to be inappropriate development within the Green Belt. The Framework advises that inappropriate development is, by definition, harmful to the Green Belt and should not be permitted except in very special circumstances. Effect on openness 15. Paragraph 133 of the Framework identifies that openness and permanence are the two essential characteristics of Green Belts. The Courts have highlighted that that the word openness is open textured and a number of factors are capable of being relevant when it comes to applying it to the particular facts of a specific case. Openness is the counterpart of urban sprawl and it does not imply freedom from any form of development, so whilst visual impact can be relevant to openness it is not necessarily relevant in every case. Furthermore, this means that it is possible that a development which would harm openness could be acceptable visually and vice versa. 16. The appeal site sits within an existing linear form of residential development along The Grove. In this visual context, I have been mindful of the variety and scale of development on immediately adjacent plots and beyond. For this reason, I am satisfied that the extended property in itself would not have a significant visual impact in this context when viewed from The Grove. 17. Nevertheless, the introduction of a much greater and more significant scale and massing of development on the appeal site would result in an undoubted adverse spatial impact on the Green Belt. Whilst I conclude that this would overall represent only a limited overall adverse effect, it would result in a permanent impact on the spatial openness of the site within the Green Belt. As a consequence, the development would be contrary to the two essential characteristics of the Green Belt. Whether the harm by reason of inappropriateness, and any other harm, would be clearly outweighed by other considerations 18. I have identified that the scheme would amount to inappropriate development in the Green Belt, and the presumption against inappropriate development Appeal Decision APP/G2245/D/19/3243221 4 means that this harm alone attracts substantial weight. The development would also have a limited adverse effect on the openness of the Green Belt. The proposal would therefore conflict with the essential characteristics of the Green Belt as set out in the Framework. 19. Notwithstanding the harm identified above, paragraph 144 of the Framework requires decision-makers to have regard to whether there are any other considerations which would clearly outweigh the harm to the Green Belt by reason of inappropriateness and any other harm resulting from the proposal, thus amounting to very special circumstances. 20. The appellant has referred me to the recent approval of a Lawful Development Certificate (LPA Ref: 19/01748/LDCPR), for a single storey rear extension and outbuilding. The submitted evidence indicates that the Gross External Area (GEA) of the permitted development scheme would essentially be the same as the GEA of the proposed scheme, at approximately 190m2. However, whilst I note the Council accepts this to be the case, the uplift in volume of the proposed development is shown by the Council to be considerably greater at 228.7m3, than that of the permitted scheme at 179.14m3. Whilst the appellant has not provided their own calculations, the Council’s calculations have not been disputed. 21. I note that the Council accepts that there is a realistic possibility that the permitted scheme would be implemented as an alternative to the proposed development, and therefore that it represents a valid fallback position, as is also contended by the appellant. However, the appellant regards it as unreasonable for the Council to have relied upon volumetric calculations with regards the comparative impacts of the permitted and proposed schemes for its decision-making. 22. In this respect, I have had regard to Policy GB1 of the Local Plan which addresses within the criteria both the need for assessment of the volume and floorspace of proposals in determining the acceptability of extensions to dwellings in the Green Belt. As set out at Policy GB1(b), the calculation of volume quite clearly informs the assessment as to whether proposals would materially harm the openness of the Green Belt through excessive scale, bulk or visual intrusion. 23. From the evidence submitted, despite the GEA of the permitted and proposed schemes being essentially the same, the proposed extension would have a more substantial impact within the Green Belt due to its significantly greater volume than the permitted scheme, with the permitted extension being subservient in its design and form, and the outbuilding possessing a limited stature and profile. In this regard, far from the permitted scheme acting as a fallback and representing support for the proposed development, it instead clearly indicates that the permitted scheme would be preferable in terms of its impact on the Green Belt. I do not therefore regard this as weighing in support of the proposed development. 24. The appellant has made reference to neighbouring properties as having been extended previously in many different ways, with some of the extensions appearing to be similar to the proposed development. However, whilst I have had regard to the character and appearance of existing development within the immediate vicinity, I do not have the benefit of an understanding of the material circumstances which lead to the decision-making for other properties Appeal Decision APP/G2245/D/19/3243221 5 within the area. Furthermore, I am mindful that where replacement dwellings have been permitted, this category of development is assessed against different criteria within the Framework and in the context of the Green Belt, and therefore such examples would not be directly comparable to the circumstances surrounding my own reasoning as set out. I do not therefore consider that a precedent for decision-making within the Green Belt has been set. 25. I have also had regard to the contention that the Council has determined another development for a residential extension on an inconsistent basis to the approach taken on the proposed scheme, in failing to undertake an assessment of the volumetric increase. However, whether this was the case or not, I have clearly set out why it is appropriate in the context of the development plan to undertake a volumetric calculation in assessing the impact of the proposed development on the Green Belt, and I do not therefore regard the previous determination as setting any kind of precedent for my decision-making in this instance. 26. I recognise that it is intended that the proposed extensions would provide an enhanced form of accommodation for the appellants and would provide flexibility in the future for the potential accommodation of ageing parents should they require additional care. I accept that as a material consideration this must carry some limited weight in support of the proposals. 27. I have also taken into account that the Council has not highlighted that the proposed development would have an adverse effect on the character and appearance of the area, a point which I have acknowledged in the assessment of the visual impact of the proposals on openness. Furthermore, in the residential context within which the appeal site is set, the proposed extensions to the property would not result in an adverse impact on the AONB as they would be contained within the existing curtilage of the dwelling and within the expected character of the protected area, and may represent a small enhancement due to the removal of existing outbuildings. No concerns have also been raised regarding the impact on the living conditions of neighbouring occupiers, on highway safety and parking, or in respect of the impact on trees and biodiversity. 28. In addition, I accept that the local economy would have the potential to have some limited benefit during the construction period, which would attract some limited weight in support of the proposals 29. However, despite the above limited weight in support of the proposed development, I find that the other considerations in this case do not clearly outweigh the harm that I have identified. Consequently, the very special circumstances necessary to justify the development do not exist. Conclusion 30. For the reasons above, and having regard to all matters before me, the appeal must be dismissed. M Seaton INSPECTOR