Appeal 3342242

The appeal is dismissed.

In the box heading above I have used the description of development from the Council’s Notice of Decision rather than the description on the planning application form. This is because the former is expressed slightly more clearly than the latter.

The main issue in the appeal is the effect of the hip to gable extension, dormer roof form and double storey side extension on the character and appearance of the host dwelling, nearby property and the streetscene.

The proposed development by reason of its combined hip to gable extension, double storey side extension and resultant roof form would be unduly prominent, visually incongruous and unsympathetic to the original architectural composition of the host dwelling, resulting in a detrimental impact on the character and appearance of the original dwelling and would be out of keeping with the character and appearance of the immediate street scene and surrounding area. The proposal thereby fails to comply with Policy BE1 of the Hillingdon Local Plan: [name] (November 2012), [name] 11, DMHB 12 and DMHD 1 of the Hillingdon Local Plan: [name] - Development Management Policies (January 2020), Policies D3 and D4 of the London Plan (2021) and Chapter 12 of the National Planning Policy Framework (2023).

The appeal site comprises a two-storey, semi-detached dwelling facing onto the junction of [address] and [address]. Its semi-pair is [address] and together they form one corner of the two roads. The appeal property is north of [address]. Both have wedge-shaped rear gardens and their frontages stand back from the corner.

The appeal site has a hipped roof form and a very shallow two storey side projection. [address] has been extended including the construction of a two storey recessed element with a crown roof with rooflights.

The surrounding area is residential in character comprising mainly semi-detached and terraced properties. Many have been extended including by constructing rear dormer structures.

The proposed development includes a single storey rear extension and a replacement front porch. Neither of these elements would cause harm to the appearance or character of the host dwelling or the nearby properties or streetscene.

The appeal site has the benefit of a Certificate of Lawful Proposed Development (ref.7946/APP/2021/4068) for a hip-to-gable roof extension and rear dormer. It also has an extant planning permission (ref.7946/APP/2023/2960) for a two-storey side extension, single-storey rear extension and front porch. Each scheme could be constructed separately but both schemes would not be lawful development. 10.Amongst the policies relevant to this case is policy DMHD 1 of the Hillingdon Local Plan: Part 2 - Development Management Policies (adopted 2020) which states that alterations and extensions to dwellings should not have an adverse cumulative impact on the character and appearance of the street scene, and should appear subordinate to the main dwelling. In respect of proposed side extensions the same policy at (C)(vi) states that where hip to gable roof extensions exist, a two storey side extension will not be supported. 11.No hip to gable roof extension and rear dormer exist at the moment at the appeal site, but it is necessary to consider the impacts of the proposed two storey side extension with a hip to gable roof and rear dormer as shown in the submitted plans. My view is that the proposed side extension would not integrate well with main dwelling once it has had a hip to gable extension and dormer constructed (or vice versa). The side extension would appear as an add-on particularly from the rear where the side extension would not sufficiently integrate or meld with the main dwelling. This would be particularly harmful at roof level where the varied roof profiles (including the sizeable dormer cheek) would be discordant. Overall it would be unsympathetic to the original architectural composition of the host dwelling. 12.In addition, the cumulative effect of the proposed roof extension/dormer and the double storey side addition, would result in a disproportionate addition which would appear overly bulky and would fail to be subordinate to the original dwelling. They would add to the lack of balance between the appeal property and its semi-pair and owing to the prominent corner plot the proposed development would be readily visible in the streetscene and tend to draw the eye, to the detriment of the pleasant rhythm of the streetscene. 13.I have had regard to other extensions which have taken place in the vicinity of the site and I have noted the comments of an Inspector in relation to, inter alia, policy DMHD 1(C)(vi) on a different site in Uxbridge for a different proposal. However, I have determined this appeal on its own individual merits and nothing I have seen or read leads me to conclude that this proposal should be allowed. 14.Consequently, I conclude that the proposed hip to gable extension, dormer roof form and double storey side extension would result in harm to the character and appearance of the host dwelling, nearby property and the streetscene. It would conflict with policy BE1 of the Hillingdon Local Plan: Part 1 - [name] (adopted 2012), policies DMHB 11, DMHB 12 and DMHD 1 of the Hillingdon Local Plan: Part 2 - Development Management Policies (adopted

and policy D3 of the London Plan (2021).