Appeal 3331239

The appeal is dismissed.

The main issues are the effect of the proposed development on: • the character and appearance of the host property and the area, including its impact on a protected tree; and • the living conditions of the adjacent occupiers at 6 and [address], with particular regard to outlook, and the availability of natural light.

According to the officer report, the site lies within the Green Suburban Typology as defined in the Council’s Townscape Character Assessment 2017, where design and planning principles include maintaining the rhythm and spacing of houses, and retaining mature trees and hedgerows.

I observed that [address] slopes steeply upwards from its junction with [address]. The dwellings either side are set back from the highway, typically behind landscaped front gardens. They are varied in terms of their architectural style and proportions, and include bungalows and more substantial two storey houses, such as No 3 broadly opposite this site. Most sit on large plots, often with gaps to their neighbours, particularly above ground floor level. This contributes to the area’s spacious character.

The host comprises a detached, well-proportioned house, on a generous ‘L’ shaped plot with gaps to its neighbours either side. A large beech tree, which is protected by a Tree Preservation Order, is located in the front corner of the adjacent plot at [address] (‘No 6’) and contributes to the area’s landscaped ambiance.

The proposed extensions would be significant in scale and the resultant building would have a greater bulk than at present. However, having regard to the [name] and Householder Development Supplementary Planning Document 2013 (‘SPD’), the proposed two storey side extension would be around half the width of the host and its eaves and ridge heights would integrate with the existing building; and the extensions would broadly respect the host’s proportions and would be faced in matching materials. Consequently, considered in isolation of its context, the scheme would comply with the SPD, and would not harm the host’s character and appearance.

However, the proposed two storey side extension would have a significant depth which, together with its clipped gable and its section of crown roof, would give it a substantial bulk. As it would be located close to the boundary with No 6, which is situated on much lower ground and has a much lower eaves, it would visually loom over that property. Having regard to the site’s context, and notwithstanding some screening provided by the protected tree, that harmful relationship would be visible ascending [address] from the west.

As illustrated in the appellant’s statement, there are crown roofs in the wider area, but this scheme’s bulk and its proximity to the side boundary would make the resultant building a domineering feature, which would be visually at odds with the [address] streetscene and its generally much more spacious character.

According to the Arboricultural Impact Assessment by Tree Sense (‘the AIA’), the protected beech is around 15 metres high, with a branch spread of around 7 metres, and it is in a good condition with a life expectancy of over 40 years. I agree that it is a high quality tree. Given its form and prominent siting it makes a significant contribution to the visual quality of the area.

The AIA concludes that if the recommendations made within it are followed, the development is achievable in arboricultural terms. Those recommendations include pruning the south-eastern spreading branches back by up to 2m to provide clearance away from the existing front elevation of No 8 and to provide suitable space for scaffolding; although a 1-2 metre reduction of all lateral spreading branches is advised to maintain a balanced and attractive form.

For its part, the Council maintains that the development would be likely to cause damage to the tree’s roots, that the proposed crown reduction would adversely affect its health and significantly reduce its amenity value, and that regular surgery would be required to maintain the crown at its reduced size.

I observed that the tree’s branches extend close to, or touch, the front faces of No 8 and No 6, and that some limited pruning may therefore be required irrespective of this scheme.

The appellant says that a 2 metre reduction in radius would be equivalent to a 29% reduction in crown volume, but that appears to have been calculated by reference to branch length. According to the Council’s Tree Officer, a 2 metre reduction in branch length would result in the loss of over 50% of the crown volume and most of the tree’s foliage. By reference to BS 3998:2010, particularly its paragraph 7.7.2, I find that calculation more persuasive. I am therefore concerned that the extent of overall crown reduction advised to maintain a visually attractive and balanced appearance would significantly impact the health and visual amenity value of the tree.

Additionally, I observed that there is a marked drop in levels immediately to the west of the tree, where planning permission was granted in 2010 for the existing house at No 6 and the two others beyond. It therefore seems to me that much more of the tree’s root system is likely to be under the plot at No 8 compared to that side. Consequently, on the basis of the available evidence, and notwithstanding the proposed tree protection measures and arboricultural method statement in the AIA, I agree with the Council that the impact of foundations and construction works would be likely to significantly impact the tree’s health.

The scheme would therefore conflict with Policies GC4 and TW3 of the Chiltern District Local Plan 1997 ([name] 2001) Consolidated 2007 and 2011 (‘CLP’). These state that trees which make an important contribution to the character of a site and the area should be retained in a good

As the proposed building would significantly harm the character and appearance of the area, the scheme would also conflict with [name] GC1, H11, H13 and H15, and Policy CS20 of the [name] for Chiltern District 2011 (‘CCS’). Amongst other things, and in general terms, these require development to be to a high design standard, which is in scale with its surroundings and in keeping with adjoining buildings having regard to matters such as frontage width and height; not to adversely affect the character and appearance of the streetscene; and to ensure a suitable distance from the flank to the curtilage boundary commensurate with the site’s context and the character of the area.

It would also conflict with the advice in the SPD that extensions should blend into the streetscene and should not adversely affect the character and appearance of the locality; and with the broadly similar stance at Section 12 of the National Planning Policy Framework (December 2023).

[name] 6 contains side facing windows, the main windows and principal outlook from, and sources of natural light to, it, are in its front and rear elevations. The depth of the proposed two storey side extension would be broadly similar to No 6’s rear projection. Consequently, whilst No 6 is on much lower ground, the scheme would not have a significant impact on the outlook from its rear facing glazing; and the garden area beyond it would not be significantly enclosed, or suffer from a harmful overbearing impact.

The bungalow at [address] (‘No 10’) contains two clear glazed windows in its flank serving a kitchen area and a dining room. However, according to the appellant’s calculation, No 6 is set in from the boundary with No 10 by around 2.7 metres, and the proposed single and two storey rear extensions would be sited no closer to it. The dining room window at No 10 has an aspect towards the boundary hedge and flank of No 6, and that outlook would not significantly change as a result of this scheme.

No 10’s kitchen is also served by rear facing glazing. Although the kitchen may be long and narrow, that glazing provides an additional source of natural light to it, and the outlook from there down that property’s garden would remain largely unimpeded. Thus, whilst the resultant dwelling at No 8 would extend further to the rear, given its siting, and having regard to the significantly lower ground level, it would not have a harmfully overbearing impact on No 10 considered as a whole; nor, on the basis of the available evidence, would it cause those occupants a significant loss of natural light, or significant overshadowing.

Summing up, the proposal would not harmfully impact the living conditions at No 6 or No 10. It would not therefore conflict with those parts of [name] GC2, GC3, H13 and H14 which seek to protect the amenities of adjoining occupiers, having regard to issues such as overbearance, and the provision of sufficient sunlight and daylight; nor with the similar stance in the SPD.

This scheme was scaled down in comparison to a previously withdraw application, a refused scheme, and a scheme which was submitted for pre-application advice. However, I have dealt with the proposal before me on its merits. In its favour, it would provide additional living accommodation for the extended family.

I have found that whilst the proposal would not harmfully impact the living conditions at 6 and [address], it would significantly harm the character and appearance of the area. The scheme’s private benefits would not outweigh the significant harm that it would cause. It would conflict with the development plan when considered as a whole. Having regard to all other matters raised, including representations by interested parties, the appeal is therefore dismissed.