Appeal 3320353

The appeal is dismissed.

I have utilised the Council’s description of the development as per the decision notice as I feel it more concisely describes the development.

The appeal site is subject to another appeal (APP/K5600/D/23/3321031). Whilst site visits for both appeals were undertaken at the same time, each case has been determined upon its own merits and are the subject of separate

The main issue is the impact of the proposal upon the character and appearance of the host property, terrace and wider Ladbroke Conservation Area with regard to design, scale and size.

The appeal site is a four-storey terraced residential dwelling with a lower ground floor level. The site is located within the Ladbroke Conservation Area (CA) and, within the relevant CA appraisal, is designated as a positive building which contributes positively to the character of the CA. Section 72 of the Planning (Listed Buildings in Conservation Areas) Act 1990 requires that special attention shall be paid to the desirability of preserving and enhancing the character and appearance of the CA.

The appeal site stands within a terraced row where properties are generally similar in terms of their character and appearance, however, I note from my site visit that there is some variation within the general design and scale of dormer windows which are present within the overall roof form of this row. This variation is further demonstrated within the appellant’s statement of case through the photographs provided. The appeal proposal seeks to construct a new dormer window, to the rear elevation, as well as introduce a new mansard roof to accommodate the proposed dormer.

The planning history for the site demonstrates that permission was previously granted for, amongst other things, widening of the existing rear dormer (PP/18/02613)1. This permission allowed a five-bay dormer. The appeal proposal before me would occupy a similar position but the previous permission had a greater set in as well as being smaller in scale which would have allowed it to remain subservient by comparison. It was noted, by the Council, that the previously approved dormer would be a maximum in this location. In addition, the previous permission was not combined with proposals for a mansard roof extension as is now the case. I find the proposal within this appeal is therefore materially difference as a result of the combination of the increased scale as well as proposed changes to the roof pitch.

I acknowledge that the Council have raised that the larger dormer window, at the neighbouring property ([address]), is one which does not have planning history and is considered a harmful historic development which is out of character with the wider terrace. Despite this I find that it is a historical development which is now part of the character of the area, given that I have no evidence before me to suggest that it would be, or could be, subject to enforcement action which could result in its amendment and/or removal. It is, therefore, of relevance to the determination of this appeal. Whilst this neighbouring addition may be larger than other dormers within the vicinity, I find that, overall, the terraced row is not defined or characterised by dormers which can be said to be uniform in terms of design, size, or scale.

The proposal would alter the existing pitch of the roof to accommodate a larger rear dormer window with the dormer incorporating six windows. The appeal site already benefits from a rear dormer which currently comprises four windows by comparison. The proposed dormer would increase the width compared to the existing dormer and, in isolation, I do not find that the principle of a larger dormer (compared to that currently present) would be detrimental to the existing context, character and appearance of the host property, terrace or the wider CA. This would be consistent with the previous approach under PP/18/02613, however, as outlined above the proposal before me is now larger, and combined with changes to the roof pitch, which would result in additional windows, increased width and further bulk and massing.

The cumulative impact of the overall proposals would result in harm to the host property, terrace and the wider CA and would result in a visually dominant addition. [name] acknowledge the ridge height would remain the same, the alteration and raising of the roof line in the new mansard to accommodate the dormer window would be incongruous and out of character when viewed in the context of the wider terrace. Whilst dormer windows are, as outlined, characteristic of the area around the appeal site and the terraced row, I have no evidence before me that the introduction of a new mansard is characteristic and find that this would interrupt the underlying overall consistency of the roof pitches within the centre of the terrace row. The larger than previously approved dormer and more windows would be exacerbated, visually, as a result of the cumulative effect with the proposed mansard resulting in a bulky 1 PP/19/06787 is acknowledged to have approved a reduction to that consented within PP/18/02613 with installation of a flush rooflight but I find this of limited relevance to the proposal before me within this appeal addition at roof level which would be out of character and visually dominant as part of the host property. The visual impact would be particularly notable from [address] and the gardens to the rear – it cannot be said to be barely perceptible.

The combination of proposals before me I find would result in less than substantial harm to the character and appearance of the CA. In accordance with paragraph 199 of the National Planning Policy Framework 2021 (the Framework), when considering the impact of the proposed development on the significance of a designated heritage asset, great weight should be given to the asset’s conservation. This is irrespective of whether any potential harm amounts to substantial harm, total loss or less than substantial harm to its significance. In accordance with the Framework, paragraph 202, where a development proposal would lead to less than substantial harm to the significance of a designated heritage asset, this harm should be weighed against the public benefit of the proposal including, where appropriate, securing its optimal viable use.

The proposal would be for alterations to a single residential dwelling. I note the appellant’s submissions regarding properties being bought and sold but do not find this a public benefit. I have no evidence before me as to the requirement for the proposals or evidence that the quality of accommodation needs to be improved beyond the properties current offering. The loft area of the dwelling has already been converted into habitable space, which I find demonstrates that the benefits, of increasing the living area in that space, can only be stated to be private on this occasion. The property itself is not listed, but makes a positive contribution to the CA, and the cumulative extensions before me present as one which would only have private benefits and not public benefits which could be weighed against the less than substantial harm identified.

The proposal would be contrary to Royal Borough of Kensington and Chelsea Local Plan 2019 (LP) Policy CL1, which requires all development to respect existing context, character and appearance, LP Policy CL2, which requires development to be of the highest architectural and urban design quality, taking opportunities to improve the quality and character of buildings in the area and LP Policy CL3, which requires development to preserve or enhance the character of the CA.

The proposal would also be contrary to LP Policy CL6 which requires that alterations and additions do not harm the existing character and appearance of the building and LP Policy CL8, which requires all roof alterations to be architecturally sympathetic to the age and character of the building and group of buildings. The proposal would also be contrary to LP Policy CL11, which requires, within CAs, development to preserve or enhance views generally within, into, and out of the CA.

I note the objections submitted by Ladbroke Association. I have discussed matters relating to the dormer and mansard within my reasoning above and matters relating to materials, glazing, could have secured by condition had the proposal been acceptable in all other regards. The volume of glazing is of limited relevance in relation to overheating or similar in terms of what is within the scope of this appeal as a planning matter.

For the reasons outlined above, and taking account all other matters raised, I conclude that the appeal should be dismissed.