Appeal 3373073

The appeal is dismissed.

An application for costs was made by [name] against Southwark Council. This is the subject of a separate decision.

On the application form the proposal was described as a ground floor extension and reconfiguration, with a small first floor addition. However, as the first floor addition was omitted from revised drawings submitted during the Council’s consideration of the application, I have taken the description in my banner from the appeal form, which is consistent with the description on Council’s decision notice.

The appellant refers to alleged factual errors in the Council’s decision and officer report. I refer to these in my reasoning below, but I have determined the appeal on its planning merits, and based on the submitted drawings.

In an email dated 14 October 2025 the appellant says that he can provide a list of planning precedents that were raised with the Council. However, having regard to section 9 of the Planning Inspectorate Procedural Guide: Planning appeals – England (2025) the appeal was made following the Part 1 procedure, whereby the appellant is required to submit all essential supporting documents from the outset with the appeal form, and cannot normally send any further material. I have therefore determined the appeal based on the submitted information.

The main issue is the effect of the proposal on the character and appearance of the host property and the area, including whether it would preserve or enhance the character or appearance of the Sunray Estate Conservation Area (‘the SECA’).

Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 states that, in respect of development affecting conservation areas, special attention shall be paid to the desirability of preserving or enhancing their character or appearance.

Following my site visit, and having regard to the Sunray Estate Conservation Area Appraisal (‘the SECAA’) and other submitted evidence, the SECA’s significance derives from its distinctive, cottage-style dwellings, which display a cohesive architectural style and appearance, and which are typically set back from the tree-lined roads on well landscaped plots. Constructed between 1920 and 1922, the estate is typical of the garden suburb movement.

The host is a two storey end of terrace property with a steeply pitched gabled roof, which is finished principally in London stock brick, and which occupies a spacious corner plot at the end of [address]. Its style is consistent with the other terraces in this cul-de-sac, and it reflects the general grain and form of development in the SECA.

As a result of the scheme, the host’s small conservatory, which is contained within its original ‘L’ shaped footprint, would be demolished, and would be replaced by a much larger extension. The extension’s general form, and its materials, which would include timber, glazing and render, would provide an appropriate visual contrast, enabling it to be ‘read’ as an addition, and a large proportion of the host’s overall garden area would be retained.

However, whilst it would be single storey, it would be a tall structure, with its walls reaching over half way between the top of the host’s ground floor windows and the window cills in the floor above. It would also wrap around part of the host’s flank wall, and it would abut, or be very close to, most of the plot’s rear boundary with [address] (‘No 25’).

As a result of its rearward siting, the extension would not impact the [address] streetscene. However, given its proximity to the plot edges, and as it would be much higher than boundary fences, it would be a dominant structure viewed from parts of No 25’s garden, and from the gardens and rear elevations of the lower lying properties on [address] to the east.

On the basis of my visit, the upper sections of its walls would also be visible, albeit to a lesser degree, looking over fences and across No 25’s garden, when approaching along the pedestrian alleyway from [address]. I therefore agree with the Council’s view, as expressed in its decision notice, that the extension would be visible from the ‘public realm’. In these public and private views, its siting, and its considerable footprint, height and scale would give it an awkward and overbearing appearance, which would not be suitably subordinate to the host, and would not allow its locally distinctive style to dominate.

I have few details of the permitted extensions in the wider area referred to at [name] of the appellant’s statement, and I cannot therefore draw any meaningful comparisons between them and the scheme before me. However, for the above reasons, I find that this scheme would harm the character and appearance of the host property and the SECA.

It would thereby conflict with Policies D4 and HC1 of the London Plan 2021, and Policies P13, P14, P20 and P21 of the Southwark Plan 2019-2036 (2022). Amongst other things, and in general terms, these require good design, which responds positively to the existing townscape with regards to matters such as height, scale, massing and arrangement, and which conserves and enhances the significance of heritage assets such as conservation areas. It would also fail to accord with the National Planning Policy Framework (‘Framework’) stance on achieving well designed places, with development which is sympathetic to local character.

Although not determinative, it would also fail to comply with the SECAA advice that extensions should not dominate the existing house, and that, as a general guide, they should be contained within the rearward projecting lines of the host and should not exceed 3.5 metres in depth. It would also fail to accord with the advice in the Southwark Heritage Supplementary Planning Document 2021 that development shall be sympathetic and shall not harm the character and appearance of conservation areas; and with the general stance in the Southwark Householder Development Supplementary Planning Document 2025 that the size and scale of extensions should be subservient to the host property and should not visually dominate the home.

Having regard to the statutory duty, I have given great weight to the conservation of the SECA. Although the Council says that the harm to it would be substantial, given the scheme’s siting and its relatively limited scale in the context of the SECA as a whole, in the language of the Framework, I consider that the harm to its significance would be less than substantial. In such circumstances, in accordance with its paragraph 215, I am required to weigh it against the scheme’s public benefits.

In this case, having regard to the Design and [name], the appellant is of the opinion that the proposal would be beneficial to the occupants as it would improve the flow and functionality of the dwelling, provide more living space, and improve connectivity to the garden. However, these are largely private benefits and are not sufficient to outweigh the harm that I have identified. Consequently, the scheme would also conflict with Section 16 of the Framework.

Summing up, the proposal would conflict with the development plan and there are no other considerations, including the Framework, to indicate that the appeal should be determined other than in accordance with it. [name] note that no objections were raised by neighbours or statutory consultees, for the above reasons, and having regard to all other matters raised, the appeal is dismissed.