Appeal 3342893

The appeal is dismissed.

The site visit was undertaken by a representative of the Inspector whose recommendation is set out below and to which the Inspector has had regard before deciding the appeal.

A new version of the National Planning Policy Framework (the Framework) was published in December 2024. [name] have had regard to the revised national policy as a material consideration, planning decisions must still be made in accordance with the development plan unless material considerations indicate otherwise. In this instance, the issues most relevant to the appeal remain unaffected by the revisions to the Framework. I am therefore satisfied that there is no requirement to seek further submissions on the revised Framework, and that no party would be disadvantaged by such a course of action.

The appeal site is situated in the Farnborough Park Conservation Area (FPCA). I shall therefore have special regard to section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990.

The main issues are the effect of the proposed development upon the character and appearance of the host property, the FPCA and valuable trees.

The Farnborough Park Conservation Area (FPCA), as described in the Supplementary Planning Guidance for the Farnborough Park Conservation Area (FPSPG) (1999), was originally historic woodland. In the twentieth century, developers acquired the land with the intention of creating a low-density, high-quality residential area while preserving the mature trees that defined the landscape. Individual buyers were permitted to hire their own architects, resulting in a distinctive neighbourhood of uniquely designed homes, with buildings influenced by the Arts and Crafts movement, the neo Classical tradition and Modernist influences. Today, the FPCA’s significance lies in its low-density layout of dwellings, many of which display distinctive architectural features and elements, all set within a verdant and sylvan landscape.

The appeal property is a two-storey dwelling located on the southern side of The Glen. Believed to be one of the original 1930s houses within the FPCA, the property retains much of its historic character despite having undergone several alterations and extensions. It features a prominent gable element with decorative arrow slits, as well as a catslide roof and enclosed porch. While the neighbouring property to the west is set further forward, no 21 aligns largely with the building line of properties to the east, resulting in a generous front garden with a sweeping driveway and front lawn. The site’s western boundary is lined with several mature trees, which lend the site a woodland character. Based on the available evidence, I consider no 21 and the appeal site to make a positive contribution to the significance of the FPCA.

Although no concerns have been raised by the Council regarding the design of the proposal in isolation, there are no doubts that it would result in the loss of important architectural features that contribute to the significance of the FPCA. The planned forward projection, increased width and height of the extensions, and alterations to the roof profile would remove the enclosed porch, decorative arrow slits, and the gabled character of the property. Additionally, the proposed roof changes would eliminate the original catslide roof entirely. These alterations would significantly change the appearance of the front elevation, disregarding the historic character of the building and resulting in the loss of the distinctive architectural features of no 21, matters to which I ascribe considerable weight.

The appellant contends that no 21 no longer reflects the high standard of large, mansion-style properties now typical in the FPCA, describing it as worn and lacking originality due to past extensions and uPVC windows. However, while no 21 has undergone considerable alterations in the past, these previous changes included the addition of a new gable with replicated arrow slits, preserving the original building’s design ethos and architectural character. Whilst the use of uPVC windows may be regrettable, they and other signs of age do not diminish the value of the property’s original historic elements, which contribute positively to the FPCA. Furthermore, while larger properties exist elsewhere within the area, that alone does not set a precedent for altering or losing no 21’s unique design details.

The appellant has drawn my attention to appeal decision APP/G5180/D/18/3202555, suggesting it implies that no 21 should not be constrained by the need to preserve its existing character. However, the referenced appeal concerns a property within an Area of Special Residential Character (ASRC), a designation distinct from a conservation area. Consequently, because this appeal relates to an ARSC, and as I have not been Appeal Planning Officer APP/G5180/D/24/3342893 provided with the full details aside from a copy of the appeal decision, a direct parallel cannot be drawn with the current proposal before me, which affects a conservation area.

I have also had regard to two nearby developments, which the appellant contends are similar to the appeal scheme. [address], 23a The Glen, the house has been remodelled but retains a repositioned front gable, preserving its original architectural character. At 17 The Glen (no 17), the development includes a double-storey side extension and altered windows. However, the extension is set back and subservient, maintaining the dwelling’s original shape and appearance, which lacks the distinctive architectural features of [site address] (no 21). Therefore, I conclude these developments are not directly comparable to the current proposal, so I have given them minimal weight in my recommendation.

The appellant has referenced the Council Case Officer report on the development at no 17, highlighting that its part crown roof design was deemed compatible with the area and the FPCA. However, the drawings indicate that no 17 already appears to feature a crown roof, making the design choice an appropriate continuation. In any case, it is not the proposed crown roof for no 21 that is seen as harmful in isolation. Rather, it is the resulting loss of distinctive features, including the catslide roof, that would be harmful to the character and appearance of the host property and the FPCA as a whole.

Overall, the proposed development would have a harmful impact on the host property and the character and the appearance of the FCPA which, it follows, would not be preserved or enhanced. Consequently, it would not comply with Policies 6, 37, and 43 of the Bromley Local Plan (BLP) (adopted 2019), which require, among other things, that the scale and form of development respect or complement the host dwelling and surrounding area, contribute positively to heritage assets, and incorporate features that enhance the area's historic character. Furthermore, the proposal would conflict with the FPSPG, which seeks to retain buildings that positively contribute to the FPCA, and with paragraph 135 of the Framework, which emphasises the importance of development being sympathetic to the local character and history, including the surrounding built environment and landscape setting.

Concerns have been raised by the Council regarding the impact the development would have upon a nearby oak tree. From my observations, T6 is a mature and healthy specimen which by reason of its form, height, size and prominent location within the front garden, makes a very positive contribution to the verdant character and appearance of the FPCA.

The appellant has submitted an Arboricultural Report1 (AR) in support of their proposal which identifies the tree in question as T6. It concludes that the proposed development would result in an incursion of up to 5% into the Root Protection Area (RPA) of tree T6. However, the presented evidence does not clearly show that the ground conditions were taken into account when drawing the RPA. Consequently, and adopting a precautionary approach, there is a 1 Tree Survey, Arboricultural Impact Assessment and [name] dated 30 March 2023 (CDS/21TG/22 c1.2). Appeal Planning Officer APP/G5180/D/24/3342893 possibility that the degree of encroachment within the RPA resulting from the proposed development would in fact exceed 5%.

Furthermore, as clearly set out in BS 5837:2012 (Trees in relation to design, demolition and construction – Recommendations), the default position should be that structures are located outside the RPAs of trees to be retained, and only where there is an overriding justification for construction within the RPA should technical solutions be considered to prevent root damage. Little evidence has however been presented to demonstrate the existence of an overriding justification in this instance. For these reasons, I consider that, having regard to the available evidence, the matter cannot be satisfactorily addressed by a condition requesting details of the foundations.

The appellant suggests that the incursion can be mitigated by contiguous rooting areas, particularly to the north and west of T6, along with specific construction methods, materials, and general precautions, asserting that these methods align with the guidance in BS 5837:2012. Technical solutions to prevent root damage should only be applied where there is an overriding justification for construction within the RPA. In this case, no such justification has been provided, so I can only assign limited weight to this mitigation proposal.

The appellant has challenged the Council’s position that the development could increase the likelihood of significant works to T6 in the future, given that the development would bring the property closer to the tree. However, as discussed, I find there to be insufficient evidence or justification to conclude that the development would not compromise the long-term health and longevity of tree T6.

Furthermore, the closer proximity of the building to tree T6 could increase the likelihood of additional works to the tree beyond what is currently necessary. While the current owners may wish to retain the tree and benefit from the shade it provides, I cannot be certain that this approach would continue once the development is built as the extended dwelling would be closer to the protected tree. Additionally, future occupiers may be more averse to any perceived risk posed by the tree. Consequently, I do not believe this means the Council could necessarily refuse any tree work within the falling distance of a development. Overall, I conclude that the development could increase the likelihood of significant work being carried out on the protected tree. Furthermore, recurrent tree works could affect its shape, which may harm its visual amenity value and potentially lead to its loss or deterioration.

Overall, and having regard to the available evidence, I cannot be certain that the appeal development could be undertaken without causing unacceptable harm to a valuable tree and the significance of the FPCA. It therefore follows the proposal would be contrary to Policies 43 and 73 of the BLP which state respectively development will not be permitted if it leads to the loss of one or more significant trees in a conservation area and that proposals are required to take particular account of existing trees on site.

The appeal scheme would cause unacceptable harm to the character and appearance of the FPCA, including to a valuable tree, to which I ascribe considerable importance and weight. The proposal would cause less than Appeal Planning Officer APP/G5180/D/24/3342893 substantial harm to the significance of the FPCA. In such circumstances, paragraph 215 of the Framework states the harm should be weighed against the public benefits of the proposal including, where appropriate, securing its optimum viable use. The proposed development would provide additional living accommodation but this would primarily benefit the occupiers of the appeal premises. Overall, there are no presented public benefits which would outweigh the identified harm.

I have taken into account all representations made on the proposal. Concerns have been raised regarding a potential loss of light and privacy to occupiers of neighbouring dwellings as a result of the development. However, the Council did address these matters within their [name] report and identified no harmful impact on the living conditions of neighbouring residents. Based on my assessment of the evidence before me, and my site visit observations, I see no reason to disagree with the Council’s conclusions in that respect.

Additionally, the issue of the development’s potential impact on neighbouring property values has also been raised. It is a well-founded principle that the planning system does not exist to protect private interests such as value of land or property and I have therefore not taken this into consideration.

For the reasons given above, the proposal would cause harm to the host property and the significance of the FPCA and create an unacceptable risk to a valuable tree. Consequently, and having had regard to all other matters raised, I recommend that the appeal should be dismissed.

I have considered all the submitted evidence and my representative’s recommendation and on that basis the appeal is dismissed.