Appeal 3321076

The appeal is dismissed.

Notwithstanding the description of development set out above, which is taken from the planning application form, it is clear from the plans and accompanying details that the development comprises an access door from the third floor rather than the second floor. The Council dealt with the proposal on this basis and so shall I.

The application is retrospective and at my site visit I was able to access the roof terrace and saw railings in place. However, I cannot be certain that the development that has been carried out is the same as that has been applied for. For the avoidance of doubt, I have therefore considered the proposal on the basis of the plans that were assessed by the Council.

The main issue is the effect of the proposal on the appearance of the building as a non-designated heritage asset, and whether it preserves or enhances the character and appearance of Westbourne Conservation Area.

As the site is within the Westbourne Conservation Area (the CA), I have had regard to Section 72(1) of the Town and Country Planning (Listed Buildings and Conservation Areas) Act 1990 which requires that special attention be paid to the desirability of preserving or enhancing the character or appearance of that area.

The CA covers a largely residential area with some commercial parades and generally consists of three and four storey rows of terraces and semi-detached villas dating from the 19th century. The frontages have typically retained their original features with grand appearances and a degree of uniformity in terms of scale and architectural detailing. Despite generally having a plainer appearance, the original historical form and architectural features of the rear elevations are still legible. This cumulatively makes a valuable contribution to the aesthetic quality of the area. The street layouts are of a traditional gridiron pattern of development, where buildings are often positioned back to back. The significance of the CA primarily derives from the consistent architectural form that is typical for its period and the unified townscape appearance.

The appeal building is a five storey terraced house and forms part of the grand terraces in the area. At the front, the house has much of its original features including the stucco frontage and although alterations and extensions have taken place at the rear, the four storey closet wing reflects the original proportions, and the traditional mansard roof is retained. The house's architectural detailing is typically reflective of other houses developed in this part of the CA and therefore makes a positive contribution to the significance of the character and appearance of the CA.

The Council considers the house to be a non-designated heritage asset based on its retaining characteristics in the form of sash windows, brickwork, decorative stucco and its overall form and proportions following the other properties in the terrace. Based upon my above assessment and my findings from my site visit, I am satisfied that given the house's architectural interest and its positive contribution to the CA, its level of heritage significance is sufficient to be considered a non-designated heritage asset.

My attention has been drawn to extracts of the Council’s Supplementary Planning Documents which relate to development and demolition in conservation areas and roof terraces. Whilst both of these documents set out where roof terraces may be acceptable taking account of the characteristics of the area, this is subject to ensuring that there is no adverse impact on the architectural integrity of the building.

The roof terrace is accessed from a door in the roof which was previously a window. The formation of a door at roof level is at odds with the hierarchy of the architectural order of the windows of the house whereby the length of the windows reduces in size moving up the floors. The doorway is no higher than the other window in the roof, however, it is longer and has a full-length door. As such, it does not match the other window in terms of height and design. The formation of a doorway at roof level therefore adversely changes the appearance of the roof.

At my site visit, I saw that windows in the mansard roof are characteristic of the terrace. The door is therefore uncharacteristic of the terrace and is a discordant addition. Whilst there is a mix in sizes of the openings of the windows in the mansard roofs of the terrace, there is a broad consistency in that these windows are positioned above the parapet of the roof, with the parapet line unbroken. Due to the positioning of the door and its height, it is lower than the parapet and the parapet line has been broken to accommodate the door. This adversely impacts the architectural integrity of the house. The house and its adjoining neighbour appear to share a parapet line at the same level which creates an element of symmetry between the buildings. However, this symmetry is disrupted due to the insertion of the door and the break in the parapet line.

At the rear, the mansard roofs produce a pleasing element of design continuity between the house and its neighbours, despite the variation in terms of the heights of the closet wings. Whilst there is a variation in height, generally the closet wing is lower than the parapet of the roof. This allows for a clear distinction between these two important and defining architectural features. The increased height of the closet wing and the railings effectively hides part of the parapet and detracts from the importance of the roof to the detriment of the appearance of the house and the character of the CA.

The railings enclose all of the roof and result in the loss of the open flat roof form impacting the characteristics of the closet wing. The presence of the railings combined with its increased height, increases the prominence of the closet wing by accentuating its outward projection and scale, and by adding to its height. At my site visit, whilst I saw roof terraces with railings in the terrace, I did not observe any examples in this terrace where the roof terrace is located on the roof of the closet wing and accessed via the mansard roof. As such, the railings at this level are a conspicuous and obtrusive feature.

The combined effect of the access door, increased height of the closet wing and railings signal the presence of a roof terrace at roof level, setting the house apart from its neighbours which it would be visually read with, that in the main do not have such features at roof level. I accept that the proposal is not visible from public views, however, it is visible from the rear windows of the surrounding properties.

For these reasons, the proposal fails to preserve or enhance the character and appearance of the CA and causes significant harm to the appearance of the non-designated heritage asset which diminishes its contribution to the significance of the CA. As a result of this, the proposal conflicts with Policies 38, 39 and 40 of the City Plan 2019 – 2040 (2021). These policies, amongst other things, seek development that is sensitively designed to ensure that important architectural details that contribute to the significance of heritage assets are conserved and sensitively integrated to avoid harm, whilst also having regard to the character and appearance of the area to positively contribute to Westminster’s townscape.

I note that the appellant considers that there are several roof terraces in close proximity to the site and particularly draws my attention to roof terraces at Nos. 14, 19 and [address]. At my site visit, I was able to view these terraces from the appeal site.

[name]. 14, the closet wing appears to be shorter in height and the terrace area is located below roof level. [name]. 24, the roof terrace is at the same height as the terrace at the appeal site. However, No. 24 appears to form part of a different terrace which differs in design from the house and its adjoining terrace, as it has a butterfly roof, is taller and has a different appearance to the appeal building. Nonetheless, I do not know the planning status of these examples. Regarding the development granted planning permission at No. 19, from the details, this relates to works at the second floor as opposed to the roof level, it does not represent a direct parallel to the appeal scheme in terms of design and relationship with the property. These examples are therefore not directly comparable to the appeal proposal and would not justify the harm I have identified above. In any event, I have come to my decision based on the circumstances of the appeal site and the details of the development proposed in this case.

The Council raised no objections regarding the proposal's impact on the living conditions of neighbouring occupiers and there is no evidence before me to reach a contrary view. However, this is a neutral matter and does not weigh in favour of the proposal.

The National Planning Policy Framework (the Framework) states that when considering the impact of a 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 terms set out in the Framework, the harm caused to the CA would be less than substantial, but nevertheless of considerable importance and weight. The Framework is clear that where a development would lead to less than substantial harm to the significance of a heritage asset, that harm should be weighed against the public benefits of the proposal1. In relation to a non-designated heritage asset, the Framework sets out that a balanced judgment is required having regard to the scale of any harm or loss and the significance of the heritage asset2.

Neither of the main parties has identified any public benefits associated with the development and there are none that I can identify. Consequently, there are no benefits that would outweigh the harm I have identified to the CA and the scale of harm that would be caused to the house as a non-designated heritage asset. Accordingly, the proposal conflicts with the aims of the Framework.

The proposal would have a significantly harmful effect on the appearance of the house and would not preserve or enhance the character and appearance of the CA. It therefore fails to satisfy the requirements of the Act and it would not be in accordance with the development plan when read as a whole. There are no material considerations, including those of the Framework, that have been shown to carry sufficient weight to indicate a decision otherwise than in accordance with it. I therefore conclude that the appeal should be dismissed.