Appeal 3324611

The appeal is dismissed.

The main issues are: • The effect of the proposal on the character and appearance of the host dwelling and surrounding area; and • The effect of the proposal on the living conditions of the occupiers of 67 and [address], with particular reference to outlook and light.

The appeal property is a two-storey detached dwelling with a hipped roof and a single storey addition to the side. This part of [address] comprises mainly of detached dwellings of a traditional design and appearance, several of which have been significantly altered and extended.

The appeal proposal is for a part single storey, part two storey rear extension and a first floor side extension, together with changes to the fenestration.

The two storey rear extension would have a depth of 5m, with the single storey extension adding a further 3m in depth. The proposed two storey rear extension would have the same eaves and ridge height as the host dwelling and given its considerable depth, would add significant bulk and mass to the host dwelling. This would be particularly apparent from the depth of the proposed flank elevations and associated bulky roof form.

The proposed side extension would also have an equivalent eaves and ridge height to that of the host dwelling although it would be set back from the front elevation so that it would appear more subservient to it. However, the proposed extensions would, in my view, combine to overwhelm the modest scale of the host dwelling and would appear as disproportionately large and bulky additions that would be detrimental to its existing character and appearance. Cumulatively the proposed extensions would fail to be subordinate to the main dwelling and would be contrary to Policy DMHD 1 of the Hillingdon Local Plan: [name] – Development Management Policies (January 2020) (LP2) in this respect.

Glimpses of the deep, largely unrelieved flank elevations would also be obtained from [address], and the combined bulk and mass of the extensions would result in a dwelling that would be at odds with the modest scale and form of the adjacent dwellings, thus resulting in harm to the character and appearance of the surrounding area.

My attention has been drawn to other examples of large extensions to dwellings in the immediate vicinity, including at Nos. 61, 63 and 65 on the same side of [address] and Nos 46 and 50 opposite. [name] have not been provided with the precise details of all of these extensions, in the case of No 61, the approved two storey rear extension had a depth of 4 metres, with the single storey extension adding a further 0.9m in depth, which in my opinion resulted in more proportional additions to the host dwelling compared to the

I also acknowledge the presence of crown roofs on several nearby dwellings and accept that the appeal proposal would not be out of keeping with this part of [address] in this regard. However, the overall depth, size and scale of the appeal proposal would result in particularly bulky and disproportionate additions to the dwelling which would be at odds with and harmful to the existing character and appearance of the surrounding area.

In conclusion, the proposal would have a harmful effect on the character and appearance of the host dwelling and surrounding area. It would conflict with Policies BE1 of the Hillingdon Local Plan: [name] – [name] (November 2012)(LP1) and [name] 1, DMHB 11 and DMHB 12 of the LP2, Policies D1, D3 and D4 of the London Plan (2021) (LP) and the National Planning Policy Framework (2023) (the Framework). These policies, amongst other matters, seek to ensure developments are of a high quality design which respects the design of the original property and surrounding area.

Policy DMHD 1 of the LP2 states (amongst other matters) that two storey extensions should not extend into an area provided by a 45 degree line of sight drawn from the centre of the nearest ground or first floor habitable room window of an adjacent property.

In terms of the neighbouring dwellings, [address] has an existing two storey rear extension. The proposed two storey extension would extend only a short distance beyond the rear of No 71 and accordingly, would not have any significant effect on the living conditions of the occupiers of No 71 with regard to light or outlook.

No 67 also has a single storey extension to the rear and a two-storey side extension and based on the information before me, I am satisfied that the proposal would not have a significant effect on the outlook, or the amount of light received by windows on the rear elevation of No 67.

The proposed single storey rear extension would add a further 3m in depth to the extension. However, it would be set in from the side boundaries and given its low flat roof design and the existing fencing and planting along the boundaries, I am satisfied that it would not result in any significant loss of outlook or light to neighbouring occupiers.

There is a side facing first floor window on the flank elevation of [address] which the Council state serves a bedroom. [name] have no substantive evidence that this is the case, the window appears to be clear glazed and is therefore likely to serve a habitable room. The proposed two storey extensions would, in my view, be likely to result in a loss of light to this window and the deep flank wall of the two storey extension would appear overbearing and harmful to the outlook from this window. Therefore, in the absence of any substantive evidence to the contrary, I find that the proposal would have a harmful effect on the living conditions of the occupiers of No 71 in this regard.

In conclusion, whilst I have found that the proposal would not be harmful to the living conditions of the occupiers of [address], it would be likely to have a harmful effect on the living conditions of the occupiers of No 71 with particular reference to light and outlook. The proposal would therefore be contrary to Policy BE1 of the LP1 and [name] 1 and DMHB 11 of the LP2 and the Framework insofar as these policies seek to protect the living conditions of neighbouring occupiers.

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