Single-storey, part two-storey rear extension and hip to gable loft conversion with rear dormer

Appeal Decision Site visit made on 6 January 2026 by P Terceiro BSc MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 14 JANUARY 2026 Appeal Ref: APP/Z3635/D/25/3375660 66 Gordon Road, Ashford, Surrey TW15 3EU • 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 Ms Batsheva Leah Apter (Shedan North Limited) against the decision of Spelthorne Borough Council. • The application Ref is 25/01013/HOU. • The development proposed is a single-storey, part two-storey rear extension and hip to gable loft conversion with rear dormer. Decision 1. The appeal is dismissed. Preliminary Matters 2. The description of development in the banner heading above is taken from the application form. I have however removed any wording which does not relate to acts of development. 3. At my site visit I observed that the part single / part two storey rear extension, hip to gable roof extension and rear dormer have been constructed and some internal alterations have taken place. However, for the avoidance of doubt, I have determined this appeal based on the submitted plans. Main Issue 4. The main issue is the effect of the proposed development on the character and appearance of the host dwelling and of the area. Reasons 5. 66 Gordon Road (No 66) is a two-storey semi-detached dwelling located within a predominantly residential road. The property forms part of a group of pairs of semi- detached dwellings which display a similar design, comprising a hipped roof, as well as a first-floor bay window and canopy on the front elevation. The dwellings have their garages to the side, and these are single storey buildings generously set back from the road. Although some neighbouring dwellings have been extended, the appeal property and those in the immediate vicinity have a coherent appearance. 6. The roof alterations, including the hip to gable enlargement and box style rear dormer window, undermine the plain and coherent roof form of the host dwelling and of those in the immediate vicinity. Furthermore, due to its considerable scale Appeal Decision APP/Z3635/D/25/3375660 2 and flat roof design, the rear dormer forms a bulky and incongruous addition to the rear roof slope of the host dwelling. 7. Taken together with the part two storey part single storey rear extension, which adjoins the existing garage, the development significantly increases the scale and mass of the existing dwelling to the rear, thereby overwhelming its host. Therefore, the extensions form discordant additions to the host dwelling and result in the scale of the extended house being out of character with the locality. 8. Thus, the development has a harmful effect on the character and appearance of the area, contrary to Policy EN1 of the Core Strategy and Policies Development Plan Document 2009. Amongst other things, this policy supports high quality development that creates buildings which respect the area, paying due regard to scale and proportions. Other Considerations 9. The appellant has drawn my attention to the planning history of the appeal property, including a certificate of lawfulness1 for a hip to gable roof extension and roof dormer window, a prior approval2 for a 6m deep single storey rear extension, and a planning application3 for a part two / part single storey rear extension, all of which have been granted by the Council. 10. The evidence indicates that the scheme before me comprises some elements which are consistent with these approvals, but the Council clarifies that the development as built does not correspond to any of the approved plans within these planning consents. This is not disputed by the appellant. 11. The appellant has referred me to case law on the subject of fallback positions, including the Mansell4 judgement. The appellant has suggested that, were I to dismiss the appeal, the first-floor element could be removed, which would align with the schemes approved under the certificate of lawfulness and prior approval. On the evidence before me, I find that there is a real prospect of this fallback position being implemented. 12. However, for weight to be afforded to the above as a fallback position it would also need to be equally or more harmful than the appeal scheme. The fall-back development would be smaller in scale and mass due to the absence of the first- floor element, and so it would add less bulk to the rear of the host building, thereby resulting in a more proportionate development that would less dominant than the appeal scheme. Additionally, even if the scheme approved under the planning application were to be implemented, the scale and bulk of that scheme would not overwhelm its host. Given such, I find that the fallback position would be less harmful than the appeal scheme. Accordingly, I afford it limited weight. Other Matters 13. The appellant has drawn my attention to other cases, where the Council considered existing fall-back positions. However, I have not been supplied with the full details and circumstances pertaining to those cases. As such, I cannot make any useful comparison between the development and those schemes. 1 LPA Ref 25/00242/CPD 2 LPA Ref 25/00223/PDH 3 LPA Ref 25/00243/HOU 4 Mansell v Tonbridge and Malling BC & others [2017] EWCA Civ 1314 Appeal Decision APP/Z3635/D/25/3375660 3 Conclusion 14. 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. For the reasons given above the appeal should be dismissed. P Terceiro INSPECTOR