Demolition of an existing rear conservatory extension and replacement with new, larger extension, replacement of existing oriel window seat and new velux window

Appeal Decision Site visit made on 24 March 2026 by Ellie Nutman BA (Hons) Decision by L McKay MA MRTPI an Inspector appointed by the Secretary of State Decision date: 5 June 2026 Appeal Ref: 6002418 2 Lebanon Park, Twickenham, TW1 3DG • 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 Andrew Savage against the decision of the Council of the London Borough of Richmond Upon Thames. • The application Ref is PA25/2682. • The development proposed is the demolition of an existing rear conservatory extension and replacement with new, larger extension, replacement of existing oriel window seat and new velux window. Decision 1. The appeal is allowed and planning permission is granted for demolition of an existing rear conservatory extension and replacement with new, larger extension, replacement of existing oriel window seat and new velux window at 2 Lebanon Park, Twickenham, TW1 3DG in accordance with the terms of the application, Ref PA25/2682, subject to the conditions set out in the Schedule below. 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. Main Issue 3. The main issue is the effect of the proposal on the living conditions of the occupiers of 4 Lebanon Park, with particular regard to outlook and light. Reasons for the Recommendation 4. The appeal property is a two-storey, semi-detached dwelling which sits along Lebanon Park, adjoining No 4. There is a dividing timber fence and trellis that adds height to the boundary treatment between the two properties, and planting to both sides. No 4 benefits from a rear projection and French doors at ground floor level that sit between this structure and the side elevation wall of No 2’s existing conservatory. 5. The Local Plan Supplementary Planning Document House Extensions and External Alterations (2015) (SPD) seeks to avoid extensions that create an unacceptable sense or enclosure or appear overbearing from neighbours. To this end, it advises that rear extensions to semi-detached properties are typically acceptable up to 3.5 metres, with greater depths requiring eaves to be lowered to around 2.2 metres at Appeal Decision 6002418 2 the shared boundary to reduce impacts. It also notes that acceptability ultimately depends on the site’s specific circumstances, which may justify a larger projection. 6. The Council noted that it had been unable to verify which room the nearest ground floor opening of No 4 serves and therefore assumed it was likely to light a habitable room. The appellant has now provided photographs and layout information that confirm the French doors serve a living room. The photographs also verify that the rear French doors would not provide the sole outlook to the room, as it also benefits from a front-facing window. The outlook from the front-facing window would remain unchanged under this proposal. 7. Although the roof of the proposed extension would have a relatively high pitch at the far end, No 4 has a long rear garden and would continue to enjoy a relatively open outlook along its length. There is already some degree of enclosure on the side facing No 2 due to the existing rear projection at No 4 and the boundary treatment and vegetation. Only a small part of the proposal would be visible over the existing boundary treatment, so the impact on the outlook from the rear window and garden of No 4 would be very limited. Given the generous size of the rear garden, the occupants of No 4 would therefore continue to benefit from an adequate and acceptable level of outlook from both within the dwelling and when using their outdoor space. The proposal would not therefore harm the living conditions of the occupiers of No 4 with regard to outlook. 8. Due to the orientation of the dwellings, any additional shading of No 4 from the proposed extension would be in the afternoon, at which point the main body of No 2 is already shading that area. The appellant’s Daylight and Sunlight Report confirms that the daylight and sunlight to No 4 would be safeguarded with the proposed extension. Consequently, the proposal would not harm the living conditions of the occupiers of No 4 with regard to light. 9. Accordingly, the proposal accords with Policy 46 of the Richmond Upon Thames Local Plan (2025) which requires that new development retains adequate outlooks for neighbouring occupants, avoiding any undue sense of enclosure and does not have an unacceptable impact on daylight and sunlight levels to neighbouring properties. 10. I also find no conflict with the aims of the SPD in respect of impact on residential amenity. Conditions 11. In addition to the standard three-year period implementation condition, it is necessary, in the interest of certainty, to define the plans which the development should be carried out in accordance with. 12. Given that the proposal would not result in the creation of a new area of flat roof, there is nothing substantive before me to suggest that there would be any potential to use the structure as a viewing platform. Therefore, a condition restricting the roof being used as a balcony or terrace is not reasonable or necessary. 13. In the interests of preserving the character and appearance of the conservation area it is necessary that appropriate measures are taken to ensure that nearby trees which make a positive contribution are not harmed during the construction of the development. However, I recommend a more succinct condition from that Appeal Decision 6002418 3 suggested by the Council, which is more proportionate to the scale of the development. 14. In line with Policy D12 of the London Plan, a condition requiring the development to be carried out in accordance with the submitted Fire Safety Strategy is reasonable and necessary. 15. Given the small scale of the development, I do not consider the Council’s suggested condition relating to on-road mobile machinery to be reasonable or necessary, therefore I do not recommend that it is included. 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 allowed subject to conditions. Ellie 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 allowed subject to the conditions in the following Schedule. L McKay INSPECTOR Schedule of Conditions 1) The development hereby permitted shall begin not later than three years from the date of this decision. 2) The development hereby permitted shall be carried out in accordance with drawing no’s: LPT (PL1)02 Rev A, LPT (PL1)03 Rev A, LPT (PL1)04 Rev A, LPT (PL1)05 Rev A, LPT (PL1)06 Rev A, LPT (PL1)07 Rev A, LPT (PL1)08 Rev A, LPT (PL1)09 Rev A, LPT (PL1)10 Rev A & LPT (PL1)11 Rev A. 3) The development hereby permitted shall be carried out in accordance with the provisions of the submitted ‘Fire Safety Strategy’. 4) The development hereby permitted shall be carried out in accordance with British Standard BS 5837:2012 “Trees in relation to design, demolition and construction.