Proposed roof alterations to allow new rear dormer

Appeal Decision Site visit made on 23 March 2026 by J Kirkaldy BSc (Hons) PGDip MRTPI Decision by John Morrison BA (Hons) MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 18th June 2026 Appeal Ref: 6004481 Elpatos, Pilgrims Way, Trottiscliffe, West Malling, Kent ME19 5EP • 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 Ian Stevenson against the decision of Tonbridge and Malling Borough Council. • The application Ref is TM/25/01494/PA. • The development proposed is described on the application form as, ‘Proposed roof alterations to allow new rear dormer’. Decision 1. The appeal is dismissed. Appeal Procedure 2. The site visit was undertaken by a representative of the Inspector whose recommendation is set out below and to which the Inspector has had regard before deciding the appeal. Preliminary Matters 3. Differing to the description of development in the banner heading above, the Council’s decision notice accurately describes the development as shown on the supporting plans as, “proposed roof alterations incorporating hip to gable, new rear dormer and extension to existing chimney stack.” This description has been used in the consideration of the appeal since it best describes the proposed development in precise and concise terms. I am satisfied that there would be no prejudice to the appellant in using this description. Main Issues 4. The main issues are a) whether the proposal would be inappropriate development in the Green Belt; b) its effect on the openness of the Green Belt; and c) 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 necessary to justify the development. Reasons for the Recommendation Inappropriate Development 5. Policy CP3 of the Tonbridge and Malling Borough Council Core Strategy (2007) (CS) states that National Green Belt policy will be applied. The National Planning Policy Framework (Framework) states that the fundamental aim of the Green Belt Appeal Decision 6004481 2 policy is to prevent urban sprawl by keeping land permanently open. Inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. 6. Paragraph 154 of the Framework sets out that development in the Green Belt is inappropriate other than in the case of specified exceptions. An exception at Paragraph 154 c) is the extension or alteration of a building, providing that it does not result in disproportionate additions over and above the size of the original building. The Framework defines ‘original building’ as being a building as it existed on 1 July 1948 or, if constructed after 1 July 1948, as it was built originally. 7. Neither the Framework nor the development plan provide a definition of ‘disproportionate additions’ and therefore an assessment of whether a proposal would amount to disproportionate additions over and above the size of the original building is a matter of planning judgement. 8. The Council’s Officer report refers to the original dwelling as constructed pursuant to planning permission granted in the 1950s (reference 50/0010186/OLD) and includes an extract of the approved plans. The building was originally constructed as a modest, single-storey two-bedroom dwelling with a hipped roof. It has been subsequently extended with a hip to gable roof alteration, dormers to the front and rear roof slopes, rear single storey extension and single storey front gabled extension. A detached garage has also been erected. These alterations and additions have significantly enlarged the original building. The Council refers to an increase in footprint of approximately 81%, together with a doubling of the building’s overall volume. 9. The appellant states that the proposal would result in a volume increase of 24 cubic metres when compared with the current existing dwelling. Whilst the proposal, when considered in isolation, represents a modest addition, when assessed cumulatively alongside the extensive previous alterations, it would result in disproportionate additions to the original dwelling. Consequently, the proposal would constitute inappropriate development in the Green Belt, contrary to paragraph 154 c) of the Framework and, by association, the aims of Policy CP3. Openness 10. The Framework explains that the essential characteristics of the Green Belts are their openness and their permanence, which have a spatial and visual aspect. 11. The appeal site lies at a lower level to Pilgrims Lane. Established vegetation provides some screening, particularly from Taylors Lane, limiting views into and out of the site. Nevertheless, the dwelling remains visible from the vehicular access and from certain vantage points along Pilgrims Lane. The openness of the Green Belt is apparent both around the appeal property and within the wider area, reflecting the spacing between nearby dwellings and the modest scale of development around the site. 12. The proposed hip-to-gable alteration would be apparent within the street scene when viewed from Pilgrims Lane and would erode openness at roof level. Although the footprint of the dwelling would remain unchanged, the increased roof mass would add to the overall bulk of the building. As a result, the proposal would lead to a reduction in and thus harm to the visual and spatial openness of the Green Belt. This would be in addition to that caused by the scheme’s inappropriateness and Appeal Decision 6004481 3 lead to further conflict with the aims of the aforementioned policy and the Framework. Other Considerations 13. The appeal site lies within the Kent Downs National Landscape (NL). I am aware of the duties to conserve and enhance its natural beauty and seek to further the purposes for which NLs are designated. The Framework requires great weight to be given to conserving and enhancing the landscape and scenic beauty in NLs. Given the scale and nature of the scheme in context, the fact they would be confined within the residential curtilage of an already evolved building and the immediate surroundings are semi built up, I do not disagree with the Council’s findings on the lack of harm to the NL. However, neither this nor a finding on no harm on matters of design, appearance, neighbours’ living conditions or highway safety would weigh in the proposals’ favour. They would be neutral. 14. The proposal would provide enlarged living accommodation for the appellant and their family. This is a private benefit to which I would afford limited weight. Conclusion and Recommendation 15. The development constitutes inappropriate development within the Green Belt and would result in harm to its openness. Substantial weight should be given to these harms. Other considerations put forward attract, collectively, limited weight. This would be insufficient to clearly outweigh them. Therefore, the very special circumstances needed to justify the development do not exist. 16. The appeal proposal would conflict with the development plan. There are no material considerations of sufficient weight, including the policies of the Framework, to suggest the decision should be made other than in accordance with the development plan. I therefore recommend that the appeal should be dismissed. J Kirkaldy APPEAL PLANNING OFFICER Inspector’s Decision 17. I have considered all the submitted evidence and my representative’s report and on that basis the appeal is dismissed. John Morrison INSPECTOR