Construction of extension to the rear of existing residential property (currently being used for holiday letting purposes)

Appeal Decision Site visit made on 24 March 2026 by F Harrison BA(Hons) MA MRTPI an Inspector appointed by the Secretary of State Decision date: 16th April 2026 Appeal Ref: 6003470 The Tiny Chapel, B6305 Low Stublick Junction to Lowgate, Lowgate, Northumberland NE46 2BP • The appeal is made under section 78 of the Town and Country Planning Act 1990 (as amended) against a refusal to grant planning permission. • The appeal is made by Mr and Mrs Steve and Anne Dunwell against the decision of Northumberland County Council. • The application Ref is 25/02830/FUL. • The development proposed is the construction of extension to the rear of existing residential property (currently being used for holiday letting purposes). Decision 1. The appeal is dismissed. Main Issues 2. The main issues are: • whether or not the proposed development is inappropriate in the Green Belt having regard to the National Planning Policy Framework (the Framework) and any relevant development plan policies; • the effect of the proposed development on the openness of the Green Belt; • the effect of the proposal on the character and appearance of the area, including the appeal property, a non-designated heritage asset (NDHA); • the effect of the proposal on ecology; and • if the proposed development is inappropriate, whether the 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 development. Reasons Whether inappropriate development 3. The appeal site falls within land defined as Green Belt. The Framework identifies that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. Framework paragraph 154 establishes that the construction of new buildings is inappropriate in the Green Belt, subject to several exceptions. Policies STP7 and STP8 of the Northumberland Local Plan 2016 – Appeal Decision 6003470 2 2036 (2022) (NLP) reflect the approach of the Framework, to the extent that they are relevant to this appeal. 4. My attention has been drawn to the exception at Framework paragraph 154 c), which allows for 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 glossary at Annex 2 of the Framework provides a definition of ‘original building’ as a building as it existed on 1 July 1948 or, if constructed after 1 July 1948, as it was built originally. 5. The appellants do not dispute the Council’s view that the appeal property in its existing form is the original building for the purposes of Framework paragraph 154 c). On this basis, the Council indicate that the proposal would result in a volume increase of over 50% but has not shown how they arrived at this figure. The appellants have not provided an alternative calculation. 6. Nevertheless, neither the development plan or any guidance contains specific limits in terms of floorspace or volume in relation to this exception. Additionally, the Framework does not provide a definition of ‘disproportionate additions’. There are different ways of assessing and measuring proportionality and I am mindful that the Framework refers to size. As such, an assessment of whether a proposal would amount to a disproportionate addition is a matter of planning judgement which goes beyond a purely mathematical calculation. 7. The proposal would result in a generous increase in built form at ground floor and first floor level, increasing both the footprint, floorspace and volume of the appeal property. As shown on the submitted plans and the 3D visualisations the external dimensions and form of the appeal property would be significantly altered by the proposal. This leads me to conclude that the extension would result in a disproportionate addition over and above the size of the original building. The layout of the site and existing domestic features of the car parking area and external amenity area do not lead me away from my findings. Case law and other Inspector’s decisions may well have accepted greater volume additions than the appeal scheme, however I do not have any details and so it is not clear that they are directly comparable to this case. In any event, I have come to my own view. 8. It has not been suggested that the proposal would meet any of the other listed exceptions at Framework paragraph 154, and there is nothing before me that would lead me to disagree. Consequently, the proposed development fails to meet any of the exceptions set out in Framework paragraph 154 and would therefore be inappropriate development, which is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. Effect on openness 9. A fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. Openness is an essential characteristic of the Green Belt that has spatial as well as visual aspects. 10. The proposed extension would result in a considerable quantum of built development where there was previously none and would cause harm to openness spatially. Despite being located at the rear of the property, the overall bulk of the built form would be clearly visible from the adjacent highway, on Appeal Decision 6003470 3 approach in either direction. Accordingly, the proposal would inevitably lead to a loss of openness in a visual sense. 11. While the appeal site is small in the context of the Green Belt as a whole, the proposal would represent a marked spatial and visual change, contributing to a small, but nevertheless detrimental effect on openness. The limited harm to openness would be contrary to the Green Belt purpose of limiting the encroachment of development into the countryside. Character and appearance 12. The appeal site lies within the open countryside and accommodates a former church, now in use as a holiday let. It is surrounded by open fields with a rural character. The appeal property occupies a prominent position at the roadside edge of the B6305, which at the appeal location is a long linear road. 13. It is not disputed that the appeal property is a NDHA. The former church’s significance is mainly derived from its age and architectural detailing, including steeply pitched roof and elegant windows. In accordance with Framework paragraph 216, and reflected in NLP Policy ENV7, in determining the appeal I have undertaken a balanced judgement having regard to the scale of any harm or loss and the significance of the appeal property. 14. The proposal would introduce a generously sized extension to the rear elevation of the property with materials to match. Despite having a lower ridge height than the original property and being set in from both sides, the bulky scale and massing of the proposal would not be well related or subordinate in size and massing to the modestly sized existing property. The shallower pitched roof has been chosen to offer an element of subservience however it would be at odds with the characteristic steeply pitched roof of the NDHA and would not be respectful to the existing historic built form. Even if the roof slates would be reused, and the original windows and stone walls would be retained internally, they would be lost from public view, undermining the ability to appreciate the NDHA’s significance. 15. The design of the scheme would weaken the legibility of the appeal property’s historic plan form in views on approach from the B6305 in either direction. In both short range and longer views, owing to the linear alignment of the road, it would be readily apparent that the proposal would be an incongruous form of development. In particular, the proposal would harmfully detract from the distinctive roof profile of the side elevation on approach from Lowgate. The proposal would not respect or complement the style and character of the existing property, as required by NLP Policy HOU9. 16. Overall, the physical presence and design of the proposal would not contribute positively to a strong sense of place. The proposal would draw the eye and visually compete with the original historic built form, diminishing the historic and architectural merit and thus the significance of the appeal property as a NDHA. 17. The introduction of similar architectural features on the extension including arched openings does not lead me away from my above findings. Neither does the suggestion that the Council has allowed larger extensions elsewhere in the county, as I do not have any details of any such scheme and so I am unable to make a meaningful comparison to this proposal. Appeal Decision 6003470 4 18. To conclude, the proposal would be unduly harmful to the character and appearance of the area, including the significance of the appeal property as a NDHA. It would be in conflict with NLP policies QOP1, QOP2, HOU9, ENV1 and ENV7 which amongst other things, require development to incorporate high quality design that makes a positive contribution to local character and distinctiveness, conserving the significance of Northumberland’s valued historic environments. 19. The Council has confirmed that NLP Policy ENV9 in relation to conservation areas was included in error on the decision notice and reference should have been made to NLP Policy ENV3. However, this policy relates to landscape character, and my attention has not been drawn to any wording in this policy that is relevant to this main issue. Accordingly, neither policy has been determinative in this appeal. Ecology 20. NLP policies ENV1 and ENV2 include a requirement that development minimises any adverse effects on habitats and species. The appellants’ Preliminary Roost Assessment (2025) (PRA) has been undertaken by a suitably qualified ecologist and found the appeal property to have negligible potential for roosting bats. On this basis it concludes that no further survey work is recommended. There is no substantiated evidence which would prompt me to disagree with the findings of the PRA. Furthermore, the suggested actions and mitigation including method statement for contractors, integrated bird and bat features incorporated into the proposal and low-level direction external lighting could be secured by appropriately worded conditions. The proposal would contribute to and enhance the natural and local environment as required by the Framework as a consequence. 21. Therefore, I conclude that the proposal would not have a harmful effect on ecology and would be in accordance with NLP policies ENV1 and ENV2. Other considerations 22. The increased floorspace created by the proposal would allow the appellants to future proof the property should they choose to move in with their family. As this is a largely private matter it attracts limited weight. 23. There would be no significant consequences for the living conditions of neighbouring occupiers or on parking provision. However, this, and any other policy compliance, including the growth of an existing tourism related business in the Green Belt, are neutral matters, weighing neither for nor against the proposal. 24. While interested parties indicate that the proposal would improve accessibility for visitors to the holiday let with disabilities by providing a ground floor bedroom, this is not what is shown on the proposed floorplans. The Council’s handling of the application has not affected my consideration of the planning merits of the case. Green Belt Balance 25. I have not found the proposal harmful to ecology however, it would be harmful to the character and appearance of the area, including the appeal property as a NDHA, in conflict with the development plan, to which I attach significant weight. 26. The appeal scheme would be inappropriate development which is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. There would be a modest reduction of openness which is harmful Appeal Decision 6003470 5 to the Green Belt. The totality of the Green Belt harm attracts substantial weight. 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. 27. I attach limited weight to the appellants’ personal circumstances which makes up the other considerations. As such, the other considerations do not clearly outweigh the harm I have identified. Consequently, the very special circumstances necessary to justify the proposal do not exist and it fails to accord with the Green Belt aims set out in NLP Policies STP7 and STP8 and the Framework. Conclusion 28. My above findings bring the proposal into conflict with the development plan, read as a whole. There are no material considerations, including the Framework, that indicate a decision should be made other than in accordance with it. Therefore, I conclude that the appeal should be dismissed. F Harrison INSPECTOR