Appeal 3288708

The appeal is dismissed in so far as it relates to the roof alterations/dormer window.

The part of the appeal that relates to the replacement of rear conservatory with single storey rear extension and changes to the external elevations is allowed and planning permission is granted for the replacement of rear conservatory with single storey rear extension and changes to external elevations at [site address] , Corsham [postcode] , in accordance with the terms of the application Ref: PL/2021/06470, dated 26 April 2021, and subject to the following conditions:

The development hereby permitted shall begin not later than three years from the date of this decision.

The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building in material, colour and texture.

The development hereby permitted shall be carried out in accordance with the approved plans: AA/19/20/01, AA/19/20/02, AA/19/20/03, AA/19/20/04, AA/19/20/05, AA/19/20/06, AA/19/20/07, AA/19/20/08, AA/19/20/09, AA/19/20/10, AA/19/20/11 and AA/19/20/12, only in so far as they relate to the single storey rear extension and changes to external elevations and not the rear dormer which is not part of the approved scheme.

The site visit was undertaken by an Appeal Planning Officer whose recommendation is set out below and to which the Inspector has had regard before deciding the appeal.

An application for costs was made by [name] against Wiltshire Council. This application is the subject of a separate decision.

The proposal includes three main components; the proposed dormer window, a single storey rear extension to replace the existing conservatory and changes to external elevations to allow for the replacement of existing UPVc windows and door with painted sash windows and a composite door, reinstatement of stonework to the front bay windows, a new window in the side elevation, and replacement of UPVc rainwater goods with steel gutters and downpipes.

The Council has raised no concerns in respect of the rear extension, with the exception of the proposed chimney stack. They also welcome the proposed alterations to the elevations on account of the more sympathetic windows, door and rainwater goods. On the basis of the evidence before me, I have no reason to find differently in this regard. Setting aside the chimney stack the extension itself would preserve and slightly enhance the character and appearance of the Corsham Conservation Area (the CA) and the alterations, particularly the changes to the windows, would enhance the CA, when compared to the unsympathetic existing windows.

Accordingly, the main issue is whether the proposed dormer window and single storey rear chimney would preserve of enhance the character or appearance of the host dwelling and CA.

The appeal property is a large detached dwelling set within a substantial plot within the Corsham Conservation area (the CA). The CA boundary encompasses the core of the historic market town as well as Corsham Park which provides the setting for the town to the east. The significance of the CA lies within the collection of historic buildings in vernacular styles, with a consistent use of local building materials. [address] is a key thoroughfare leading to and from the centre of the town and is of residential character in the vicinity of the site, with a range of individually designed dwellings with a consistent use of materials which reflects the palette within the wider CA. Although there are some exceptions, dormer windows are not prevalent in the surrounding area.

The appeal dwelling is a traditional property with ashlar stone to the front and brick to the back, with bay windows set either side of the entrance and a simple pitched roof. There is an existing flat roofed, modest dormer extension with a balcony to the rear which can be seen from [address] at the rear of the appeal property, looking towards the CA. However, its modest scale is such that it does not erode the simple and pleasing form of the original property. Whilst the principal elevation contains the main architectural features the form, the rear is visible from the public realm. Overall, despite some unsympathetic alterations through the introduction of UPVC windows, doors and rainwater goods, the dwelling contributes positively to the character of the CA on account of its traditional form and use of materials.

The dormer is proposed to take up the majority of the width of the roof. Although it would be set down form the ridgeline in a similar fashion to the existing dormer and stepped in slightly from the eaves, it would have a considerable width. The horizontal emphasis of the dormer, its substantial width, in addition to its flat roof profile, would represent an overtly modern and box-like addition that would contrast unsympathetically with the simple and traditional pitched roof of the original property. Due to the scale and width of the dormer as well as the height of the roof and the open view from the rear, this would be a highly visible incongruous addition to the host dwelling and would be prominent within the surrounding area and in views from [address] towards the CA.

A flat roof rear dormer located on [address] was permitted in 2016, which can be seen from the rear of the appeal property. This development has a different context as 15a is set back from the road, within a smaller plot and therefore there are small gaps between the neighbouring dwellings. The dwelling is also smaller in terms of width and it faces outside of the CA. Therefore, there is little impact to the street scene and CA in comparison to the proposed appeal dormer. Consequently, the presence of other dormer windows does not lead me to alter my conclusion on the harm that would be caused by the proposal.

Chimney stacks are present throughout the area, albeit that they are normally flush with the external wall of the associated dwelling, projecting only at ridge level. In contrast, the proposed chimney would have an external stack. Nonetheless, it would align with the flank wall of the main dwelling, would be set back into the site and would be modest in scale, such that it would not be prominent in views from the CA. In fleeting views that would be available, it would not look particularly alien given the presence of many chimneys in the area. Moreover, it would be attached to the rear addition, which would read as a modern extension to the property with a clear distinction from the original part of the dwelling. Given the above, I am satisfied that the chimney would preserve the character and appearance of the CA.

In view of the above, the proposal would cause harm to the character and appearance of the CA in respect of the rear dormer but would preserve and enhance the character and appearance of the area in respect of the rear extension and chimney and other alterations. The dormer would only be seen from a small part of the CA, and would cause less than substantial harm. Nonetheless, any harm to a CA is a matter that attracts great weight, given the statutory duty to pay special attention to the desirability of preserving or enhancing the character or appearance of the area and the requirements of paragraph 199 of the National Planning Policy Framework (the NPPF).

Where harm to the CA would be less than substantial that should be balanced against any public benefits. There would be benefits of having extra space in the appeal property, to allow for the growth of the family. However, these would be private benefits and as such these would only attach limited weight and would not outweigh the harm identified. The alterations to the bay windows, fenestration, doors and rainwater goods would enhance the appearance of the façade with associated benefits to the CA and public realm. The replacement of the conservatory with a more sympathetic structure would also result in an enhancement of the character of the CA, albeit limited due to its concealed position. [name] attach weight to those benefits those improvements could be carried out independently of the dormer window. There is nothing to indicate that the benefits are reliant on the harmful part of the scheme. They are clearly severable and planning permission could be granted for the acceptable elements without the harmful impact of the dormer. In those circumstances the public benefits associated with aspects of the proposal do not outweigh the harm that would be caused by the dormer window.

For the reasons detailed above, the dormer extension would cause harm to the character and appearance of the host dwelling and Corsham Conservation Area. This is contrary to Policies 57 and 58 of the [name] (2015), which together seek to enhance local distinctiveness by being sympathetic and responding positively to the special characteristics or appearance of the site, local context, Conservation areas and historic environment in terms of appropriate building layouts, built form, mass, scale, elevational design and to effectively integrate the building into its setting. It would also conflict with Policy HE1 of the Corsham Neighbourhood Plan, which seeks new development that responds to and integrates with the local surroundings and demonstrates good quality design by respecting the scale, character and historic built fabric of existing surrounding buildings and using good quality materials that complement the existing historic vernacular of Corsham.

Conversely, the proposed rear extension and alterations to the fenestration would preserve and enhance the CA, thereby conforming to the above policies.

No conditions are available that would mitigate the harm arising from the dormer. With regard to the single storey rear addition and alterations to external elevations, in addition to the standard time period for commencement of the development, a condition has been recommended requiring the development accord with the approved plans. This is necessary, as it provides certainty and precision. A condition requiring the use of materials matching that of the existing building is also necessary to ensure an appropriate appearance for the development.

For the reasons given above and having regard to all other matters raised, I recommend a split decision is issued dismissing the roof alterations/ dormer window but allowing the ground floor rear extension and alterations to external elevations and granting planning permission for those elements, subject to the conditions set out above.

I have considered all the submitted evidence and the Appeal Planning Officer’s report and on that basis, I agree with the recommendation and shall allow the appeal in part and grant planning permission subject to the conditions set out and dismiss the appeal in respect of the roof alteration/ dormer window.