Appeal 3331550

The appeal is dismissed.

While the appellant has described the proposal as in the above heading, the Council has referred to it as a first-floor extension to the existing outbuilding. From my inspection of the plans, the Council’s description more accurately reflects the development sought. I have assessed the proposal on that basis.

The surname of the appellant given in the above heading, which is absent on the application form, is taken from the completed planning appeal form.

Since the appeal was lodged, a revised National Planning Policy Framework (the Framework) has been published. The Framework does not raise any new matters that are determinative to the outcome of this appeal.

The main issues are the effect of the proposed development on the character and appearance of the local area and on the living conditions of the occupiers of [address] with regard to outlook, light and sense of enclosure.

The appeal property is a large detached 2-storey house of individual design within a predominantly residential area, wherein dwellings are similar in type and vary in scale, style and general appearance. To one side of the main house and set back from the adjacent footway behind frontage planting is a single storey, L-shaped outbuilding. With its restricted width facing the road, flat roof and plain rendered walls, the existing outbuilding has a low profile and an unassuming presence within the local street scene.

The proposal is to erect a mansard style roof on top of the outbuilding to create a new first floor that would be served by windows and roof lights with matching external materials. By adding new built form and height, the outbuilding would significantly gain prominence in the streetscape. That a corner of the completed outbuilding would step forward of the main flank wall to [address], which is a dwelling that backs onto the side of the site, would accentuate its presence in the street scene. As a result, the finished outbuilding would become a conspicuous feature in the street scene. Furthermore, a new mansard roof with 2 front windows would also introduce domestic features that would be visible from [address]. This arrangement would draw the eye because the finished outbuilding would more closely resemble a dwelling and yet appear unusually diminutive in the context of far more substantial and taller dwellings on either side of the site. Consequently, the proposal would be an obtrusive, discordant element and an unwelcome addition to the local area.

From what I saw, the area to which the site belongs, whilst having a coherent residential character, is capable of successfully accommodating a variety of buildings in terms of size and style. However, the overall visual effect of the appeal scheme would be unconvincing because the finished outbuilding would appear incompatible in its context. I recognise that the flat roof of the existing outbuilding contrasts with the pitched roof slopes of nearby properties. However, unlike the proposal, the overall visual effect is not jarring because ancillary outbuildings with flat roofs are typically found in residential areas.

On the first main issue, I conclude that the proposed development would materially harm the character and appearance of the local area. Accordingly, the proposal is contrary to Policy D3 of The London Plan (LP), Policies CS1 and CS5 of Barnet’s Local Plan ([name]) (CS) and Policy DM01 of Barnet’s Local Plan (Development Management Policies) (DMP). These policies aim to ensure that new development represents high quality design, preserves or enhances local character and respects local context. These principles underpin the advice within the Council’s Supplementary Planning Document, Residential Design Guidance (SPD), with which the proposal would also conflict.

The side elevation of the proposed extended outbuilding would face the rear elevation of No 27, which is just beyond the boundary of the site. It is the occupiers of this neighbouring property that are most likely to be affected by the proposed development.

From the photographs provided by the appellant, No 27 has a number of rear windows from which the existing outbuilding is likely to be evident including a full-length ground floor window that faces towards the site. Due to its height and position close to the shared boundary with No 27, I consider that the proposal would be likely to overly dominate the view from this ground floor window and result in a significant reduction in the amount of natural light reaching it. For the same reason, the appeal scheme would further enclose the space at the back of No 27 to the extent that it would unduly heighten a sense of enclosure, which would be unneighbourly.

I recognise that the new built form would block some views from the upper side windows of No 42 towards the rear of No 27 and so reduce the potential for overlooking between these adjacent properties. Even so, this benefit does not outweigh the significant harm caused to the living conditions of the occupiers of No 27 that I have identified. As such, there is a conflict with [name] D3 and D6, CS Policy CS5, DMP Policy DM01 and the advice within the Council’s SPD insofar as they aim to safeguard residential amenity.

Once complete, the proposed extension would provide valuable additional living space for the appellant as a prayer room. However, this consideration does not outweigh the harm identified in relation to the main issues.

An interested party raises additional concerns including the effect of the proposal on privacy, overdevelopment of the site and the future use to which the outbuilding might be put if planning permission were to be granted. These are important matters and I have considered all the submitted evidence. However, given my findings on the main issues, these are not considerations that have been critical to my decision.

The proposed development would conflict with the development plan, as a whole. There are no material considerations, including those of the Framework, which indicate that the decision should be taken otherwise than in accordance with the development plan.

For the reasons set out above, and having regard to all other matters raised, I therefore conclude that the appeal should be dismissed.