Appeal 6000954

The appeal is dismissed.

In the interests of clarity, I have taken the description of development from the decision notice and appeal form rather than the application form.

Under Article 3(1) and Class AA of Part 20, Schedule 2 of the Town and Country Planning (General Permitted Development) (England) Order 2015 as amended (the GPDO), planning permission is granted for the construction of up to two additional storeys of new dwellinghouses immediately above the topmost storey on a detached building together with associated works. For development to be permitted it must satisfy the limitations set out at paragraph AA.1 and the conditions at paragraph AA.2 of Class AA.

An additional plan has been prepared and submitted by the appellant at appeal stage. The plan shows the existing and proposed plant heights (sheet No. 014). As this additional plan does not materially evolve the scheme, I am content to accept its submission for information purposes and am satisfied that no party with a potential interest in the outcome of this appeal is prejudiced by me doing so.

Before prior approval under Class AA can be evaluated, it is necessary to determine whether or not the proposal falls to be considered as ‘permitted development’.

The Council has claimed the proposed dwellinghouses would not comply with [name].1 (l) of the GPDO and therefore would not comprise permitted development. This is on account that the height of the replacement plant (and louvre screening) as measured from the lowest surface of the new roof on the principal part of the extended building would exceed the height of any existing plant as measured from the lowest surface of the existing roof on the principal part of the existing building.

On the basis of the additional submitted plan in relation to the proposed plant heights, the Council consider that the proposal would accord with the requirements under AA.1 (l) of Part 20, Class A of the GPDO subject to a condition which seeks to ensure that the proposed rooftop plant equipment to be installed shall not exceed the height of the existing plant. I find nothing that contradicts this conclusion and therefore consider that the proposal comprises permitted development.

However, the Council has objected to prior approval being granted on account of its effect on the external appearance of the building. Accordingly, the main issue is whether prior approval should be granted having regard to its effect on the external appearance of the building.

Where prior approval is required in relation to the effect of development on the ‘external appearance’ of a building, it will be a matter of planning judgment as to whether consideration is given to the effect in terms of the building’s intrinsic design and/or to the effect in terms of the building’s relationship with adjoining or nearby properties.

The appeal site is a three-storey office building with lower ground car parking area. The building is located on [site address] , a no through road, which slopes gently downwards from Regents Park Road. At the corner of [site address] and Regents Park Road is the seven-storey [address], which is a prominent building of modern design reflecting its corner position. In contrast, [site address] predominantly comprises a mix of three and four storey buildings. Due to the topography, the roofs of buildings step downwards from Regents Park Road. The appeal building is one of three buildings, which includes [address] and [address] which follow the same architectural design, with hipped crown roofs. The stepped pattern of the roofline and similar design provides a rhythmic appearance to the roofscape and contributes positively to the character of the area.

The proposal involves the construction of two additional storeys with a flat roof resulting in an overall increase in the height of the building by approximately 5.5m. The fenestration detailing of the existing building transitions from larger windows at ground floor level to smaller ones above, creating well-proportioned elevations. The incorporation of full height glazing on both new floors would be in stark contrast with the existing fenestration patterns resulting in a pronounced vertical emphasis. The proposed storeys would depart markedly from the well-proportioned appearance of the existing building, introducing a top-heavy addition. Whilst the additional storeys would be set back slightly from the main elevations of the host building it would do little to prevent the full extent to the additional storeys being evident when viewed within [site address] . Overall, the scale and massing of the additional storeys would result in a dominant, disproportionate and incongruous addition to the appeal building.

The substantial additional height would compete with that of the neighbouring [address] building and disrupt the prevailing stepped roof pattern along [site address] . Although the proposed height would align with that of [address], the additional storeys would project significantly above other surrounding buildings, thereby undermining the coherence of the street’s roofscape. Moreover, replacing the crown hipped roof design with a flat roof would diminish the consistent appearance of the roofs of the group of three buildings.

I therefore conclude that the proposal would result in unacceptable harm to the external appearance of the building. As such the proposal would not comply with condition AA.2 (1) (e) of Schedule 2, Part 20, Class AA of the GPDO and prior approval should not be granted.

I am aware that the Finchley Church End Conservation Areas boundary runs through Regents Park Road in proximity to the appeal site. Mindful of the statutory duty set out in section 72 of the Planning (Listed Buildings and Conservation Areas Act 1990, I have had special regard to the desirability of preserving its setting. Nevertheless, given the location and scale of intervening development I consider that the proposal would preserve the setting of the conservation area and the contribution it makes to its significance. I note that the Council had no concerns in this regard either.

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