Appeal 3323372

The appeal is dismissed.

As the description of the proposed development varies between documents submitted for this appeal, I have used the description from the Council’s decision notice, as this is an accurate and full description that has also been used by the appellant for their statement.

The main issue is the effect of the proposal on the character and appearance of the appeal dwelling, the terrace of which it forms part and that of the local area, with reference to the [address] Conservation Area (the CA).

The appeal dwelling is a palisaded two storey mid-terrace house that sits in a terrace of similar modestly scaled London yellow stock brick Victorian artisan dwellings. The roofs are of a butterfly form, set behind a continuous corniced parapet. The terraced houses demonstrate a consistent and cohesive design, which, along with the continuous corniced parapet, results in a coherent street frontage. This makes a substantial contribution to the high quality Victorian streetscape of the local area, which is a major element in the significance of the CA.

The CA is a heritage asset to which I have a statutory duty under section 72 of the Planning (Listed Buildings and Conservation Areas) Act 1990. I must pay special attention to the desirability of preserving or enhancing the character or appearance of a Conservation Area.

The Council identifies the houses in the terrace as non-designated heritage assets (NDHA), their significance as such resting in their consistent architectural features and coherence as a group. There is no restriction on when NDHA status can be recognised and I concur with the Council that the significance of the appeal property, given its mainly unaltered appearance and consistence and coherence with the other houses in the terrace, which is recognised as a key feature within the CA, results in it being NDHA, as defined by the provision of the PPG1. I have considered the effect of the proposal in line with paragraph 203 of the National Planning Policy Framework (2021) (the Framework) accordingly.

The proposal is for a mansard roof extension that would replace the existing butterfly and centre valley roof form. The mansard roof would have pairs of dormer windows to the front and rear. This would entail the raising of the party walls and chimneys that sit between the appeal dwelling and its neighbours in the terrace. The materials proposed would match those used in the existing building.

Although marginally set back from the existing parapet, the height of the proposal and the extended party walls and chimneys would result in it being visible in front and rear views of the appeal dwelling, as well as in more tangential views from up and down the street and from gardens and neighbouring houses to the rear of the appeal dwelling. This would interrupt the existing consistency of the butterfly roofscape of the terrace and detract from the continuous parapet line as a defining feature of the street frontage and roofscape.

The proposal would, therefore, appear as unsympathetic to the existing character and appearance of the appeal dwelling. Given the height and scale of the proposal, it would not appear as a subordinate addition to the appeal dwelling, but would rather appear as an unduly prominent and dominating feature to both the appeal dwelling and the terrace of which it forms part. This would not accord with design guidance given in the [name] and Extensions Supplementary Planning Document (2019) (the SPD)

The Brookmill public house, a locally listed building and NDHA sits on the opposite side of the street and reflects the consistent Victorian character of the local streetscape. The prominence and scale of the proposal would result in it appearing as an incongruous addition to the streetscape. This would weaken the consistency of the streetscape and roofscape that forms the setting of this locally listed building and NDHA.

The proposal and the loss of the original roof form would be readily apparent in street views and wider views of the appeal property from within the CA. In these views it would appear as unsympathetic to the local streetscape and roofscape within which it would sit, thereby interrupting the consistent architectural appearance of the terrace and weakening the established local character and appearance. As such, the proposal would fail to reflect the significance of the CA that I have identified. This would not accord with design guidance given in section 5.12.4 of the [name] and Extensions Supplementary Planning Document (2019). 1 Planning Practice Guidance: [name] (2014) (as amended)

The appellant has drawn my attention to other mansard roof extensions approved or built in the wider local area. However, these approved mansard extensions are to terraced houses on streets that, despite being made up of Victorian houses, demonstrate less consistent and cohesive architectural design than that of the terrace of which the appeal dwelling forms part. These streets are also on hills, resulting in a change in level between pairs of terraced houses and a concomitant stepping in corniced parapets.

As such, I do not find that these recently approved mansard extensions provide a precedent for the proposal, as they would have been considered on their own merits, and I have done likewise in my consideration of the appeal proposal. I have, therefore, only given the other approved and existing mansard extensions in the local area moderate weight in my considerations.

[name] appreciate that the appellant has sought to overcome the reasons for refusal of an earlier application for a similar proposal, for the reasons given above, the proposal would result in substantial harm to the character and appearance of the appeal dwelling and its significance as a NDHA, as well as to the terrace of which it forms part. The proposal would also result in significant harm to the setting of the locally listed PH and to the character and appearance of the local area, thereby, failing to preserve or enhance the character or appearance of the CA.

The proposal would, therefore, be in conflict with policies 15 and 16 of the [name] (2021), policies DM30, DM31, DM36 and DM37 of the Lewisham Development Management Local Plan (2014), Policy D3 and HC1 of the London Plan (2021) and Sections 12 and 16 of the National Planning Policy Framework (2021) (the Framework). These collectively seek to ensure that development is of high quality design, having due regard to the importance of preserving or enhancing heritage assets.

I find that the harm to the appeal dwelling as a NDHA would be substantial, although the harm to the CA would be less than substantial. In accordance with the Framework, great weight should be given to the conservation of those assets.

The additional living space provided by the proposed mansard extension would be a primarily private benefit and I have given significant weight to the effects on the character and appearance of the appeal property as an NDHA and the terrace of which it forms part and to the setting of the locally listed PH. I must give considerable importance and weight to the effect on the significance of the CA. I consider that the benefits of the proposal identified do not outweigh the harm that I have identified.

For the reasons given, I conclude that the appeal should be dismissed.