Appeal 6006126

The appeal is dismissed.

The main issue is the effect of the proposed development on the character and appearance of the area, including whether the proposal would preserve or enhance the character or appearance of the [address]/[address] Conservation Area (CA).

The appeal site is a mid-terrace, two storeys over basement dwellinghouse forming part of a locally listed terrace within the CA. The significance of the CA derives largely from its late Georgian and early Victorian terraces, which display a coherent and consistent architectural composition, including well-ordered front elevations, traditional materials, and a clear hierarchy of built form.

The appeal property contributes positively to this significance through its front elevation, which reflects the established proportions, detailing and rhythm of the terrace and forms part of a harmonious and unified streetscape. This hierarchy also extends to the rear of the properties, where projections are typically more varied but remain clearly subordinate to the principal building, typically terminating well below the eaves of the principal roof. The relationship between the principal building and its subordinate rear projection contributes to the overall architectural legibility and character of the terrace, forming part of its significance.

The proposed extension would increase the height of the outrigger beyond this established pattern and introduce a flat-roofed form with minimal set down from the main roof. As a result, it would appear as a visually dominant and discordant addition that would undermine the established hierarchy of the building and disrupt the existing symmetry between the paired outriggers.

I therefore find that the proposal would result in harm to the character and appearance of the area, and would fail to preserve the appearance of the CA. In doing so, it would conflict with the statutory duty under section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990, which requires special attention to be paid to the desirability of preserving or enhancing the character or appearance of conservation areas.

Whilst there are examples of rear outriggers within the terrace that have been extended beyond two storeys, the details and circumstances of those developments are not before me. In any event, such extensions harm the significance of the heritage asset by undermining the established hierarchy of the building and the terrace, whereby rear projections are intended to remain clearly subordinate to the main form. The addition of a further extension of this nature would add to that harm, resulting in cumulative harm to the character and appearance of the CA.

The rear of the terrace displays some variation; however, variation does not in itself establish acceptability where a clear underlying pattern and hierarchy remains evident. Notwithstanding this variation, the prevailing character remains one of subordinate rear projections. The proposal would materially depart from this pattern.

Furthermore, the rear of the terrace is visible from the public realm, including from City Garden Row, which lies adjacent to the CA. This visibility forms part of how the terrace is experienced in its wider setting. The openness of the rear aspect allows clear views of the built form, such that the proposal would be readily perceptible and would contribute to an incremental erosion of the terrace’s character and appearance.

The proposed alterations to the front lightwell, including the replacement of the existing window with double doors, would not undermine the established hierarchy of the building or the terrace. They would be limited in scale, confined to the lower ground floor, and relate to a part of the building that is not a defining component of either the locally listed building’s significance or the wider CA. Furthermore, similar alterations are evident within the terrace, indicating that such features do not harm its character and appearance. This element of the proposal would therefore not result in harm to the significance of the locally listed building and would preserve the character and appearance of the CA.

The proposal would therefore result in less than substantial harm to the significance of the CA and the locally listed building. In accordance with the National Planning Policy Framework, this harm should be weighed against the public benefits of the proposal. The additional accommodation and associated optimisation of the dwelling would be private benefits to the occupiers, and I find no identified public benefits that would outweigh the harm identified.

The proposal therefore conflicts with Policy D4 of the London Plan 2021 (LonP), which requires development to respond positively to local character and context and achieve high-quality design, and Policy HC1 of the LonP, which requires development to conserve the significance of heritage assets and to actively manage the cumulative impacts of incremental change, as well as policies PLAN1, DH1 and DH2 of the [name] and Development Management Policies 2023, which require development to be of high quality contextual design, conserve or enhance the significance of heritage assets, and avoid cumulative harm to the character and appearance of conservation areas. The proposal would therefore also fail to preserve the character and appearance of the CA contrary to the statutory duty set out in section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990.

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, I conclude that the appeal should be dismissed.