Demolition of existing rear conservatory and removal of roof and existing fenestration. Erection of two-storey front extension and construction of basement. Raising of roof ridge height and erection of 1 No. dormer window to side and 1 No. dormer window to rear with updated fenestration and associated landscaping

Appeal Decision Site visit made on 9 June 2026 by Thomas Courtney BA(Hons) MA MRTPI an Inspector appointed by the Secretary of State Decision date: 9 July 2026 Appeal Ref: 6006723 9 Lonsdale Road, Dorking, Surrey RH4 1JP  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 Miss Laura Groom against the decision of Mole Valley District Council.  The application Ref is MO/2025/02529.  The development proposed is the demolition of existing rear conservatory and removal of roof and existing fenestration. Erection of two-storey front extension and construction of basement. Raising of roof ridge height and erection of 1 No. dormer window to side and 1 No. dormer window to rear with updated fenestration and associated landscaping. Decision 1. The appeal is dismissed. Preliminary Matters 2. In the interest of conciseness, the description of development in the banner heading above is based on the Council’s decision notice. Main Issues 3. The main issues are:  the effect of the proposal on the character and appearance of the appeal dwelling and surrounding area, and whether it would preserve or enhance the character or appearance of the Dorking Conservation Area;  the effect of the proposal on the living conditions of the neighbouring occupiers with particular regard to outlook and light; and  the effect of the proposal on highway safety with particular regard to parking. Reasons Character and appearance 4. The appeal property is a modest early twentieth-century detached dwelling on the eastern side of Lonsdale Road. It has a subdued, cottage-like appearance, with compact proportions, a simple pitched roof form and restrained detailing. It sits within a spacious plot and is set back from the road, forming part of a small group of detached dwellings, including Nos. 5 and 7, which have a broadly similar form and architectural character. Appeal Decision 6006723 2 5. The site lies within the Dorking Conservation Area (DCA). I have a statutory duty under Section 72 of the Planning (Listed Buildings and Conservation Areas) Act 1990 (the 1990 Act) to pay special attention to the desirability of preserving or enhancing the character or appearance of the conservation area. 6. Lonsdale Road forms a distinct part of that heritage asset. The Conservation Area Appraisal identifies its informal character, varied plot widths and varied building line on the eastern side of the road, strongly defined boundary walls such as flint walls and cast-iron gates and railings. It also notes that the houses on Lonsdale Road are read as a group and share aspects of scale and form (large gables to the street and materials). The significance of this part of the Conservation Area therefore derives not from strict uniformity, but from the collective quality of detached and semi-detached houses of broadly compatible scale, form and materials set within a spacious, landscaped street. 7. The appeal dwelling reads as part of a cohesive row of dwellings with Nos 5 and 7. They share architectural similarities, featuring steeply pitched roofs with prominent front-facing gables, creating a consistent roofscape. They have relatively narrow proportions and a subdued, cottage-like or Arts and Crafts influenced character, expressed through simple forms rather than elaborate ornamentation. These dwellings have a staggered arrangement, creating visual depth and an attractive rhythm rather than a continuous building line. Each dwelling is read as part of this balanced group whilst retaining its own identity. These qualities make a positive contribution to the character of the streetscene and reflect the shared aspects of scale, form and materials identified in the DCA appraisal. 8. The appeal dwelling therefore contributes positively to the significance of the DCA. Although not a building of high individual architectural status, its modest scale, simple pitched roof form, set-back siting and relationship with neighbouring dwellings help reinforce the attractive, staggered and spacious composition of this part of Lonsdale Road. 9. The proposed dwelling would incorporate traditional detailing and would introduce materials which reflect features found locally. I also acknowledge that the increase in ridge height would be relatively modest. However, the proposal would substantially increase the eaves height, project the building forward and introduce a considerably larger roof form. Together with the enlarged footprint, these changes would materially increase the bulk and visual mass of the dwelling. 10. As a result, the proposal would fundamentally alter the proportions and character of the appeal property. Its existing modest and recessive appearance would be replaced by a substantially larger and more visually assertive building. Whether or not the crown roof would be readily visible from public viewpoints, the enlarged roof volume would appreciably change the building’s silhouette and relationship with its neighbours. 11. The appeal dwelling and Nos 5 and 7 presently have an attractive staggered symmetry and shared grain, with each building reading as part of a coherent group. The proposed increase in scale and forward projection and the change in appearance of the appeal dwelling would erode that balanced composition and reduce the spacious character of the site and surrounding area. 12. The proposed extensions and alterations would result in a building that would be read as disproportionate and incongruous. It would erode the legibility of the Appeal Decision 6006723 3 existing staggered pattern of development in this location and would alter the distinctive cottage-like appearance of the existing house. The proposal would thus reduce the contribution the site makes to the DCA. Given this, I find that the proposal would fail to preserve the significance of the DCA. 13. Paragraph 212 of the National Planning Policy Framework (the ‘Framework’) advises that when considering the impact of development on the significance of a designated heritage asset, great weight should be given to the asset’s conservation. Given the impact of the proposal on the protected historic characteristics and significance of the DCA, I find the harm to be less than substantial in this instance but nevertheless of considerable importance and weight. The harm would be at the higher end of this scale. 14. Under such circumstances, paragraph 215 of the Framework advises that this harm should be weighed against the public benefits of the proposal. The proposal would provide more spacious and modern accommodation for the occupiers of the dwelling. However, that would principally amount to a private benefit accruing to the occupants of the property rather than a public benefit for the purposes of the Framework and therefore attracts little weight in the heritage balance. 15. I also acknowledge that the replacement of the existing mix of uPVC and deteriorating timber windows with traditional painted timber windows would represent a modest enhancement to the appearance of the building and, consequently, a modest public benefit. Nevertheless, that limited benefit would not outweigh the identified harm arising from the proposal's excessive bulk, visual mass and its failure to preserve the character and appearance of the DCA. I conclude that the public benefits of the proposal would not outweigh the less than substantial harm identified, to which great weight must be given. 16. I therefore conclude that the proposal would have an adverse effect on the character and appearance of the appeal dwelling and surrounding area and would fail to preserve or enhance the character or appearance of the DCA. Accordingly, the proposal would fail to satisfy the requirements of the 1990 Act, the Framework and would conflict with Policy EN6 of the Mole Valley Local Plan (2020-2039) (the ‘Local Plan’) insofar as it seeks to ensure that proposals conserve and enhance heritage assets, are of high design quality and do not harm elements that make a positive contribution to conservation areas. 17. The proposal would also conflict with Policy EN4 of the Local Plan, the Dorking Design Code, the Council's ‘Design Guidance for House Extensions and Outbuildings’ Supplementary Planning Document (SPD) insofar as they seek to ensure proposals are well-designed, are of an appropriate scale, complement the character of the area, and respond positively to the prevailing pattern of development. Living conditions 18. The proposal would substantially increase the scale of the appeal dwelling. The increase in eaves height, enlarged roof form, greater footprint and forward projection would cumulatively result in a building of appreciably greater bulk and visual mass. 19. Consequently, the proposal would materially alter the relationship between the appeal dwelling and the neighbouring property at No 7. The appeal dwelling Appeal Decision 6006723 4 presently has a relatively modest presence when viewed from No 7. By contrast, the proposed development would present a considerably larger and more visually dominant built form that would appear unduly prominent and overbearing when experienced from the neighbouring property, particularly when viewed from the rear extension, which appears to accommodate the principal kitchen/dining/living space, as well as from its south-facing windows, private patio and garden. The increased scale and mass of the proposal would materially diminish the outlook currently enjoyed by the occupiers of No 7. 20. I have had regard to the submitted daylight and sunlight assessment. Whilst I acknowledge its conclusions and that it indicates the principal rooms would continue to satisfy the relevant BRE guidance overall, the assessment also identifies reductions in daylight and sunlight to individual neighbouring windows. Moreover, the drawings accompanying the assessment appear to contain inconsistencies in the identification of the ground floor windows at No 7, with the labels for windows W4 and W7 appearing to overlap on the same opening. This makes it difficult to determine precisely which windows have been assessed. 21. In addition, the side sash window serving the rear extension facing the appeal site, which was evident during my site visit and contributes daylight and sunlight to what appears to be the principal kitchen/diner living accommodation, does not appear to have been separately identified or assessed. Consequently, whilst the BRE assessment has informed my consideration, I have also relied upon my own observations of the relationship between the buildings. 22. Given that No 7 lies immediately to the north of the appeal property, the increased eaves height, enlarged roof form and forward projection would inevitably reduce the amount of daylight and sunlight reaching the neighbouring south-facing windows. Although I do not find that the technical evidence demonstrates a severe loss of daylight and sunlight in isolation, the proposal would nevertheless result in noticeable reductions in natural light to the side bay window and the south-facing window and rooflight serving the rear extension. Those reductions, when taken together with the proposal's increased bulk and overbearing presence, would result in an unacceptable effect on the living conditions of the occupiers of No 7. 23. Turning now to the effects on the neighbouring property at Mayfield to the south. Whilst the relationship is less constrained than that with No. 7, the submitted daylight and sunlight assessment nevertheless identifies appreciable reductions in daylight to the kitchen windows serving that property. Having regard to the increased scale and proximity of the proposal, I find that the enlarged dwelling would also result in a more enclosing outlook and a noticeable reduction in daylight to the principal kitchen accommodation. Although this harm would be less pronounced than that experienced at No. 7, it reinforces my overall conclusion that the proposal would fail to safeguard the living conditions of neighbouring occupiers. 24. I have also considered the proposed fenestration and am satisfied that the development would not give rise to unacceptable overlooking or loss of privacy. However, that does not outweigh the identified harm arising from the proposal's increased scale, massing and its effects on outlook and daylight. 25. Accordingly, I conclude that the proposal would cause unacceptable harm to the living conditions of the neighbouring occupiers of No 7 and Mayfield through its Appeal Decision 6006723 5 overbearing presence and associated reduction in outlook and light. It would therefore conflict with Policy EN4 of the Local Plan and with the Council's ‘Design Guidance for House Extensions and Outbuildings’ SPD insofar as they seek to ensure that proposals do not significantly affect the amenity of neighbouring occupiers. Parking 26. Policy INF2 requires a five-bedroom dwelling in this location to provide three off- street parking spaces. Although the submitted drawings do not identify a detailed parking layout demonstrating three marked spaces, my site visit indicates that the forecourt would likely be capable of accommodating the required level of parking without reliance on on-street spaces. Furthermore, there is no objection from the Highway Authority and there is insufficient evidence before me to conclude that the proposal would result in unacceptable highway safety impacts or severe residual effects on the local highway network. 27. Whilst the detailed parking arrangement has not been shown, this is capable of being secured by a planning condition requiring the submission and implementation of a parking and turning layout prior to the first occupation of the extended dwelling. Subject to such a condition, I am satisfied that the proposal would provide adequate off-street parking and would not lead to unacceptable pressure on on-street parking. 28. Accordingly, I find no conflict with Policy INF2 of the Local Plan which seeks to ensure that developments provide a minimum number of off-street vehicular parking spaces, for residents and visitors, in accordance with the adopted standards. Other Matters 29. Assertions of logical development because of the unusual plot arrangement do not alter the heritage and design findings, and the absence of harm to biodiversity, trees, highways and other matters are neutral considerations that neither weigh against or in favour of the proposal. Conclusion 30. The proposal conflicts with the development plan and the material considerations do not indicate that the appeal should be decided other than in accordance with it. 31. For the reasons given above the appeal should be dismissed. Thomas Courtney INSPECTOR