First floor rear extension and new dormer to existing three-storey semi-detached single family dwelling house

Appeal Decision Site visit made on 4 November 2025 by E Nutman BA (Hons) Decision by M Russell BA (Hons) DipTP MRTPI an Inspector appointed by the Secretary of State Decision date: 12 February 2026 Appeal Ref: 6000447 25 Rosemont Road, Richmond TW10 6QN • 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 Radim Radkovsky against the decision of the council of the London Borough of Richmond upon Thames. • The application Ref is PA25/1760 • The development proposed is first floor rear extension and new dormer to existing three-storey semi-detached single family dwelling house. 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. Following its decision on the planning application and prior to the consideration of this appeal, the Council adopted the Richmond Local Plan (2025) (LP). This supersedes the London Borough of Richmond upon Thames Local Plan (2018). The appellant would have been aware of the emerging LP as it is referred to in the Council’s report and Policies 28 and 30 are referenced in the reason for refusal on its decision. The wording of these policies has not materially changed in terms of the adopted versions. Therefore, I have had regard to these policies as being part of the up-to-date development plan and accordingly attach full weight to them. 4. The Council’s decision notice is clear that its concerns relate to the ‘proposed rear fenestration to side extension’. Through reference to the accompanying officer report, this relates to ‘a large, double height window proposed for installation to the rear elevation of the more modern side extension’. This detail is shown on the proposed drawings and there is no dispute that it forms part of the proposed development. I have therefore defined the main issue on this basis. 5. The Council's decision identifies harm to the character and appearance of the host building, which it identifies as a non-designated heritage asset, but not to the St Matthias Conservation Area (CA). This also reflects the findings of the Council’s accompanying report. Even so, given the appeal site's location in the CA, I have a statutory duty under Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 as amended, to pay special attention to the desirability of preserving or enhancing the character or appearance of the CA. I have therefore taken the CA into account in defining the main issue. In this regard, Appeal Decision 6000447 2 the Council’s report refers to Policy 29 ‘Designated Heritage Assets’. I have requested a copy of this relevant policy and have assessed the proposal against it alongside the other relevant policies of the LP. Main Issue 6. The main issue is whether the proposed window to the rear elevation of the existing side extension would preserve or enhance the character or appearance of the CA, including but not limited to the effect on the host building. Reasons for the Recommendation 7. The significance of the CA derives from the high-quality villas built in response to the arrival of the London and South Western Railway at Richmond in 1846. Early building took place around Montague Villas (Rosemont Road). The building style seen along Rosemont Road is largely defined by the interesting brick detailing and symmetry of dwellings. 8. 25 Rosemont Road (No 25) is a large Victorian-era, semi-detached dwelling which sits within a cluster of similarly designed buildings which are identified as buildings of townscape merit (BTM) on the ‘Proposals’ map within the St Matthias and Sheen Road Study (1994). Similar to other buildings within this cluster, No 25 incorporates London stock brick elevations, with red brick and quoin detailing to its front elevation. Another key feature are the building’s windows which are domestic in scale and mainly multi-pane in design. Its distinctive architecture and the cohesion of the building within the cluster of BTMs warrants non-designated heritage asset status (NDHA), also positively contributing to the character and appearance of the CA. 9. The host building has a two-storey side extension, built during the 1970s, which features a flat roof with a parapet wall. Whilst the side extension is a more modern addition to the host property, its subservient form and its detailing, notably including its similarly styled multi-paned windows, ensure that it suitably respects the aesthetic of the NDHA. 10. Even if the proposed window to the rear elevation of the existing side extension has been reduced in scale when compared with a previously refused planning application at the site, its single pane design extending over two floors, would be significantly at odds with the smaller and mainly multi-paned design of other windows on the NDHA. It would also not reflect the modestly scaled windows which prevail in the CA, including those most prevalent on the cluster of BTMs. 11. Even though there would be limited visibility of this window from public vantage points it would be an unsympathetic feature seen from within the appeal site for occupiers of the host dwelling and any visitors. It is also unclear who has control over the trees that provide screening between the site and the neighbouring school and therefore how they would be maintained in the long term. In any case, limited visibility does not obviate the need for good design which positively relates to the host dwelling and the distinctive quality of the CA’s built environment. In this regard the window would unacceptably erode the traditional characteristics of the CA’s built environment and the consistency of the NDHA’s architecture. 12. The appellant’s statement cites examples of permissions granted for window fenestration at 13 Rosemont Road (Ref 17/1380) and 19 Rosemont Road Appeal Decision 6000447 3 (19/3618). However, from what I can ascertain, these examples sit within facades of single storey projections. In any case, limited examples do not justify a discordant feature that would not respect the architecture of its host and which would erode the traditional characteristics of the CA. 13. I have a statutory duty under Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 as amended, to pay special attention to the desirability of preserving or enhancing the character or appearance of the CA. Factoring in the limited public visibility of the proposed window, the harm resulting from this element of the proposals on the CA and to the NDHA would be at the lower end of less than substantial having regard to the National Planning Policy Framework (the Framework). 14. Nevertheless, the Framework is clear that great weight should be given to the conservation of heritage assets. In this instance the harm identified should be weighed against the public benefits of the proposal. No public benefits have been put forward, sufficient to outweigh the harm identified. 15. I conclude, the proposed window to the rear elevation of the existing side extension would not preserve or enhance the character or appearance of the CA, including but not limited to the effect on the host building which is a NDHA. Consequently, the proposal is contrary to Policies 28, 29 and 30 of the LP (2025) which require that proposals are compatible with the local character, including the relationship to the existing townscape, as well as proportions, form, materials and detailing; that all proposals in Conservation Areas are required to preserve, and where possible, enhance the character and appearance of the Conservation Area; and that they seek to preserve, and where possible enhance, the significance, character and setting of non-designated heritage assets, including Buildings of Townscape Merit. Conclusion and Recommendation 16. For the reasons given above and having had regard to all other matters raised, I recommend that the appeal should be dismissed. E Nutman 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. M Russell INSPECTOR