Appeal 3278802

The appeal is dismissed.

The main issue is whether the proposed development would preserve or enhance the character or appearance of the Shaftesbury Park Estate Conservation Area.

The appeal concerns a terraced house which faces [address]. It is within the Shaftesbury Park Estate Conservation Area, the significance of which lies mainly in the quality of the historic buildings in the vicinity, including the terraces which line [address] and the adjoining streets.

The terrace in which the appeal property is situated maintains a high degree of visual consistency along the [address] frontage. With a few exceptions, most of the houses in this part of the street are of a broadly similar design and appear to have retained most of their original features. A strong sense of consistency is also displayed in adjoining streets, including [address] immediately to the south. These attributes directly contribute to the quality of the Conservation Area.

The proposed alterations to the front of the appeal property are relatively minor and would have little effect on the appearance of the terrace as seen from [address]. However, the proposed mansard roof extension would represent a more significant change as it would alter the shape of the roof. Although this would be situated at the rear of the appeal property, it would nonetheless be visible from some parts of [address].

The rear elevation of the terrace has a somewhat less consistent appearance than the front. I saw on my site visit that the appeal property has a first-floor rear extension, while No [address] (further along the same terrace) has both a first-floor rear extension and a mansard roof extension similar to that being proposed in the current appeal. All of these features can be seen from public vantage points in [address], although views are confined to the part of the street closest to the junction with [address].

Yet despite the presence of a skylight window, the rear roof slope of the appeal property maintains its original form. When walking along [address] in a westerly direction towards the [address] junction, the roof of the appeal property comes into view and can be seen alongside the unaltered roofs of the adjoining properties on either side. Hence, seen from this part of the street, the rear roof slope of the terrace appears to maintain a consistent appearance. The mansard roof extension at No [address] does not come into view until closer to the road junction and is most noticeable in views looking down [address] in an easterly direction. In contrast, the rear roof slope of the appeal property can be seen when approaching the site from both the east and west and hence is in a somewhat more sensitive location.

Although the existing first-floor extensions at the rear of the appeal property and No [address] are larger and bulkier structures than the proposed mansard, they are lower in height and do not affect the consistency of the roofline. By changing the shape of the roof and introducing glazing, the mansard extension would disrupt the relatively consistent roofline in the part of the terrace which the appeal property is situated. Even though the extension would represent a comparatively small feature within the wider streetscape, it would nonetheless erode the consistent appearance of the terrace thereby undermining the significance of the Conservation Area.

I note that mansard extensions of the type being proposed are recommended within the Housing SPD1. Indeed, I have been provided with examples of similar roof extensions that have been approved elsewhere in the area. However, in my view, the circumstances of those cases are not equivalent to that of the proposal before me in this appeal. While mansard extensions may be appropriate in some locations, they are not typical features of the street scene in the immediate vicinity of the appeal property. In this particular case, the proposed extension would appear inconsistent with the prevailing pattern of development and so would not preserve the heritage asset in the manner advocated by the [name] and associated policies.

My attention has also been drawn to an Appeal Decision2 where a proposal for a mansard roof extension at No [address] was dismissed on the basis that it would disrupt the unbroken roof slope of the terrace. I was able to view this property myself and note that no other mansard roof extensions are visible from the rear (unlike in the current appeal where the roof extension at No 54 can be seen from [address]). However, for the reasons given above, the roof extension being proposed in the current appeal would also have a disruptive effect on the traditional appearance of the rear roof slope, despite the presence of the existing mansard nearby. 1 Wandsworth Local Plan Housing Supplementary Planning Document, [name] 2016. 2 Appeal Decision: APP/H5960/D/18/3195310

In reaching this decision, I am mindful that paragraph 199 of the Framework3 says that ‘great weight’ should be assigned to the protection of heritage assets. However, the harm would be less than substantial and in such circumstances the Framework advises that this harm should be weighed against any public benefits associated with the development. [name] do sympathise with the appellant’s desire to improve the property, the benefits would be entirely private in nature. Hence the harm would not be outweighed in this case.

I therefore conclude that the proposed development would not preserve or enhance the character or appearance of the Shaftesbury Park Estate Conservation Area. It would conflict with Policies DMS1, DMS2 and DMH5 of the Wandsworth Development Management Policies4. Together, these policies promote appropriate standards of design and the protection of heritage assets. The appeal is therefore dismissed.