Appeal 6001688

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.

The description of development above is taken from the Council’s decision notice. This omits the proposed outbuilding which I understand was removed from the proposals during the course of the application.

The Council and appellant agree that the roof conversion and dormers, and the single storey elements are acceptable. Based on the findings of my site visit, I see no reason to disagree.

Accordingly, the main issues are the effect of the proposed two storey side and rear extension on the living conditions of the occupants of [address] (No 207) with regard to outlook and light and whether the proposal would have an acceptable effect on trees.

The existing configuration means that No 207 is sited further forward towards the highway than the appeal dwelling and as such, the side elevation of the latter is highly visible from the rear windows and garden of No 207. However, due to the single storey garage, the main bulk of the existing appeal dwelling is set away from this shared boundary. As a result, the occupants of No 207 currently enjoy a largely unimpeded outlook from their rear windows.

The proposed development would introduce a substantial two storey form in close proximity to the shared boundary with No 207. Owing to its depth and proximity to the boundary, it would present as a dominant and visually intrusive feature above the existing boundary fence within views from the rear windows of No. 207, including the conservatory.

While the appellant refers to a sunlight and daylight report, there is not such a report before me as part of this appeal. Even if this matter were found to be acceptable under a previous appeal, based on the evidence, I cannot establish with certainty that the same circumstances would apply here.

Given the proposed scale and its proximity to the shared boundary, together with the site configuration that places the appeal dwelling to the south of No. 207, the garden area closest to No 207 and the windows nearest to the development would be very likely to experience additional overshadowing beyond current conditions. On the basis of the information before me, it cannot be established that those effects would be acceptable.

The proposal would also extend beyond the front elevation of the existing garage, aligning approximately with the middle and first floor oriel windows on the side elevation of No 207. Due to its height and close positioning, the proposal would appear as a dominant feature in views from these side windows, creating an increased sense of enclosure. These windows, however, appear to serve secondary functions, with the associated rooms benefitting from primary outlook through other front and rear facing windows. Although the proposal would reduce the outlook from the oriel windows, this effect alone would not amount to an unacceptable impact on the living conditions of the occupants of No 207.

No. 207’s side elevation faces south, and the proposed development would not physically encroach upon the oriel windows. I therefore do not consider that the proposal would result in unacceptable overshadowing or loss of daylight to these openings. Any minor losses would, given their secondary nature, not materially harm the living conditions of the occupants.

Overall, I conclude that the proposed development would harm the living conditions of the occupants of No 207 through loss of outlook, an overbearing effect, overshadowing and loss of light. The development therefore conflicts with Policies D3 and D6 of the London Plan 2021, and [name] 11 and DMHD 1 of the Hillingdon Local Plan Part Two Development Management Policies 2020. These policies seek to ensure that development does not adversely affect the amenity, daylight, sunlight or outlook of neighbouring properties.

The area of [address] in which the appeal site is located is of a verdant character, contributed to by the presence of many trees and shrubs, some of which are located within the rear gardens of properties.

I recognise that there is a certain degree of dispute over the accuracy of the Arboricultural Impact Assessment (AIA) dated 10 August 2025. The AIA identifies the removal of 3 [name] trees (T3 & T5, [name]; T6, [name]) 1 [name] tree (T4, Yew) and 2 [name] groups (G1, [name]; G2 Ash, Yew and Hawthorn). It also identifies the retention of trees T8 and T9 which are “mature dominant/intermediate trees of good extension growth and crown density”, respectively.

Despite this, it was observed at the site visit that a number of trees within the rear garden (T3, T5, and T6 as shown on plan P2906B) had already been removed. I understand the felled trees also included trees T8 and T9, which had been earmarked for retention. On this basis alone the submitted AIA is clearly inaccurate as a technical document supporting the proposed development.

Notwithstanding their siting within the appeal dwelling’s rear garden, it is clear from the evidence placed before me that these trees had a clear visual contribution to the verdant character and appearance of both the site and area when experienced both from the public realm and private properties along [address]. The removal of these trees has undermined and diminished the character and appearance of the area, which the suggested replacement planting would be unlikely to adequately replace. The scheme has therefore failed to satisfactorily demonstrate the retention or enhancement of trees on the appeal site.

For these reasons, I find conflict with Policies DMHB14 of the Hillingdon Local Plan Part Two (2020) and G7 of the London Plan (2021). These policies set out that all developments are expected to retain or enhance existing trees and that development affecting trees will be required to provide an accurate tree survey. They go on to state that where trees of merit are identified, tree root protection areas and an Arboricultural method statement will be required to show how the trees will be protected. Where trees are to be removed, proposals for replanting of new trees on-site must be provided or include contributions to offsite provision.

The appellant notes that the proposal would not have a harmful effect on the character and appearance of the host dwelling and its contribution to the area. Whilst this may be the case, the visual effect of the proposed changes to the appeal dwelling is not in itself an issue contested by the Council, and is not determinative within this recommendation.

For the reasons given above 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 report and on that basis the appeal is dismissed.