Appeal 6002312

The appeal is allowed and planning permission is granted for erection of terrace to existing rear elevation (second floor) at [site address] , London [postcode] , in accordance with the terms of the application, Ref 2025/3093/P, subject to the following conditions:

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

The development hereby permitted shall be carried out in accordance with the following approved plans: Location Plan, 101-02-DR-002 and 101-02-DR-006.

All new external work shall be carried out in materials that resemble, as closely as possible, in colour and texture those of the existing building, unless otherwise specified in the approved plans.

The application form provided with the appeal does not include a description of the proposed development. The appellant’s appeal form describes the development as “small terrace on existing roof extension”. This differs from the description used by the Council when consulting on the application, which states “erection of terrace to existing rear elevation (second floor)”. This is a more precise description of the proposed development, therefore I have used the Council’s description in my decision. I am satisfied that no parties would be prejudiced by this, and I have determined the appeal accordingly.

The appeal follows the Council’s failure to determine the application within the prescribed period. However, it has indicated that had it been able to issue a decision, it would have refused permission on the grounds that the proposed roof terrace would represent an uncharacteristic and incongruous addition that would detract from the heritage character and symmetry of the building, and fail to preserve the character and appearance of the Dartmouth Park Conservation Area. An objection from a neighbouring resident also raises concerns in respect of overlooking and privacy from the terrace.

Having regard to the above, I consider that the main issues are the effect of the proposed development on: • the character and appearance of the host property, and whether the proposed development would preserve or enhance the character or appearance of the Dartmouth Park Conservation Area (the CA); and • the living conditions of neighbouring residents, with particular regard to privacy.

The appeal site comprises a flat to the upper floors of a four-storey, semi-detached property in a residential area. The properties close to the site have generous rear gardens, and a large area of intervening land and green space is between these and the buildings beyond on [address]. The site lies within the CA, which is a large, predominantly residential area with interspersed uses scattered throughout. Dartmouth Park Avenue comprises a mix of late 19th century large red and grey stock brick villas varying between semi-detached and short terraces of buildings. It is identified in the Dartmouth Park Conservation Area Appraisal and [name] (January 2009) (the CAAMS) as one of the grandest roads in the CA.

The appeal site and the majority of other properties on Dartmouth Park Avenue, in surrounding streets and in the wider CA are identified as positive buildings. The CAAMS describes the CA as having a variety and complexity that charts the history of domestic architecture from the late 18th century to the present day. The significance of the CA, as it relates to this appeal, therefore derives from this architectural and historic interest.

The host property forms a pair with [address], and these largely appear as three-storey properties when viewed from the street, with a lower ground floor level. Their front elevations share some similarities in terms of fenestration and bay windows. However, the side elevations differ at ground floor level around the entrances, with a simpler sloping roof appearance to No 5 compared to a larger and more decorative design to the host property, which are clearly visible in views from the street.

There is some symmetry to the rear elevations of the two properties in terms of their fenestration and the three-storey rear wings that extend from the lower ground floor level up to the first floor with sloping roofs. These differ in appearance with a render finish to the rear elevation to the wing of the host property, whilst to No 5 this is brick. Two-storey flat roof projections to the rear elevations of both properties at the lower ground and ground floor levels also differ, with the host property featuring black metal railings with double doors above allowing for use of a modest external terrace, whereas the roof to No 5 is unaltered.

The general form of Nos 5 and 7 contributes to a degree of consistency in their overall appearance, although there is also variation between them. There is also variety in the scale and appearance of properties along Dartmouth Park Avenue. Adjacent to the appeal site, Nos 9–15 form a terraced group with differing design and materials to the host property. These do not have rear wings, whilst some feature lower ground floor rear extensions, with a terrace above the extension to No 9. There are rear wings to Nos 1 and 3, although these differ from Nos 5 and 7, with their roofs sloping down from the eaves level of the main roof rather than set further down. This also appears to be similar for other rear wings on Dartmouth Park Avenue and [address], therefore whilst rear wings form part of the character of the area, there are variations between buildings. The host property contributes to the significance of the CA, comprising part of the variation in architecture in the area, and as a positive building within Dartmouth Park Avenue.

The CAAMS notes the erosion of architectural details and unsympathetic roof alterations are negative features of the sub area in which the host property sits. Furthermore, alterations to roofscape and inappropriate roof terraces are issues that affect large areas of the CA, with rear slopes often as important as the front slopes as views are available from neighbouring streets and buildings. There is moderate spacing to the side of the host property and the neighbouring buildings. This enables some limited views from the street towards the outer side elevations of the rear wings and their sloping roof form, rather than being a significant view or gap. Unlike some streets within the wider CA, the rear of the host property is not visible from Dartmouth Park Avenue or from streets within the wider area, with views of this largely limited to the rear gardens of surrounding buildings.

The Council’s Home Improvements Camden Planning Guidance (January 2021) (the CPG) sets out guidance on balconies and terraces. Given its modest scale in relation to the sloping roof, the proposed development would not result in its loss, and it would be a subordinate addition to this part of the property. The CPG aims for balconies to be set in within the roof slope of pitched roofs when possible. However, due to the floor level, this does not appear to be a practicable solution in this instance. The use of black metal railings would integrate well with the character of the property and the area. Whilst this section of sloping roof has not been altered, and there does not appear to be similar development in the surrounding area, the development would not appear as an incongruous addition to the host property. It would not increase the height of the rear wing’s rear wall and would largely preserve the form of this small area of sloping roof. It would primarily be seen from the rear of surrounding properties, therefore given the limited views to the side elevation, there would be limited visual impact on the street scene and the wider townscape.

Although the development would result in some loss of symmetry to the rear of Nos 5 and 7, this would be modest in the context of their rear elevations and the overall scale and form of the properties. Furthermore, there are already variations to their front, side and rear elevations, such that these do not have an entirely uniform or unaltered appearance. Given it would primarily be discernible from the rear of properties in the immediate area rather than surrounding streets, the wider impact of this minor loss of symmetry on the significance of the CA would also be limited. Accordingly, the development would not be an unacceptable addition that would undermine the host property’s architectural style or harm its character and appearance. It would therefore have a neutral effect on the significance of the CA.

For the above reasons, I conclude that the proposed development would not materially harm the character and appearance of the host property, and it would preserve the character and appearance of the CA. It would therefore accord with Policies D1 and D2 of the Camden Local Plan (2017) (the CLP) and Policies DC2, DC3 and DC4 of the Dartmouth Park Neighbourhood Forum Neighbourhood Plan (March 2020). Amongst other things, these policies aim to secure high quality design that respects local context and character, ensure extensions are subordinate in scale, and that development within conservation areas preserves or enhances the character or appearance of the area. For the same reasons, the proposal would accord with the CPG.

The development would introduce a modest sized external amenity space at a high level to the host property. At present there is overlooking of rear gardens between neighbouring properties from their rear windows, which includes from the appeal property. There is also overlooking from the property’s existing terrace area at first floor level, although this is limited given its small scale and as views towards some neighbouring properties are screened to a degree by the rear wing.

The proposed terrace would be set off the boundary with properties to either side. The host property is also set forward slightly from the rear of the group at Nos 9-15 providing some further separation from the rear gardens of these. Due to the relationship with neighbouring properties, the development would not result in overlooking into the rear windows of adjacent properties. There is also nothing before me to indicate it would result in unacceptable overlooking towards any habitable room windows to the side elevation of No 9.

Use of the terrace would increase the potential for overlooking towards No 9 in particular, as well as other rear gardens. However, due to its position on the property, its modest depth and overall size, I do not consider this would result in significant or unacceptable harm in this instance, nor require mitigation measures.

I conclude that the proposed development would not unduly harm the living conditions of neighbouring residents, with particular regard to privacy. It would therefore accord with Policy A1 of the CLP, which seeks to ensure that the amenity of neighbours is protected. For the same reasons, the proposal would accord with the Camden Planning Guidance, Amenity (January 2021).

The Council’s submissions include details of a previous planning application1 at the host property for an external terrace above the rear wing and other alterations, which was refused. That application proposed a materially different scheme to the development before me in terms of its scale and design, and the impact upon the host property and the CA. However, for the reasons set out above, I find that the development would be an acceptable addition to the property.

Details of a planning application2 at the adjacent No 9 have also been provided, which granted permission for development, including a single storey rear extension at lower ground floor level with terrace and other alterations. The relevance of this to the appeal has not been explained. However, it does indicate the difference in architectural style between Nos 7 and 9. This permission does not alter my conclusion on the effect of the development on the host property and the CA. 1 Planning application ref: 2024/4849/P 2 Planning application ref 2017/6277/P

In addition to the standard time limit, a condition specifying the approved plans is necessary in the interests of certainty. The submitted plans do not show the materials to be used to the outer parts of the terrace, therefore a condition requiring the external materials to resemble those of the existing building is necessary to preserve the character and appearance of the property and the CA.

For the above reasons, the proposal would comply with the development plan taken as a whole, and material considerations do not indicate a decision should be made other than in accordance with the development plan. I therefore conclude that the appeal should be allowed.