Appeal 3345547

The Council describe the proposed development as ‘the erection of a single storey wrap around extension to the rear and side, two storey rear extension, followed by conversion of garage to habitable accommodation, conversion of roof space to habitable use to include 2x side dormers, following the demolition of existing conservatory and 1x chimney stack’. This description more comprehensively describes the proposal and has been used in the Decision that follows.

The appeal is allowed and planning permission is granted for the erection of a single storey wrap around extension to the rear and side, two storey rear extension, followed by conversion of garage to habitable accommodation, conversion of roof space to habitable use to include 2x side dormers, following the demolition of existing conservatory and 1x chimney stack’ at [site address] , Ickenham, Hillingdon [postcode] in accordance with the terms of the application, Ref 41605/APP/2024/302, subject to the following

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the following approved plans: Location Plan, 100_01, 100_02, 100_03, 100_04, 100_05, 100_06, 100_07, 100_08, 100_09 and 100_10.

The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building.

Notwithstanding the provisions of the Town and Country Planning (General Permitted Development) Order 2015 (as amended) (or any order revoking and re-enacting that Order with or without modification), no additional windows, doors or other openings shall be constructed in the walls or roof slopes of the development hereby approved.

The side facing dormer windows facing No. 110 and No. 114 shall be glazed with permanently obscured glass to at least scale 4 on the Pilkington scale and be non-opening below a height of 1.8 metres taken from internal finished floor level for so long as the development remains in existence.

Access to the flat roof over the extension hereby approved shall be for maintenance or emergency purposes only and the flat roof shall not be used as a roof garden, terrace, balcony, patio or similar amenity area.

Planning permission was granted for a similar development to that described by the Council. The appellant now seeks to increase the length of the side dormer windows by a further 2m towards the rear. As there are no objections to any other aspects of the appeal proposal, this decision focuses only on the issue in contention. The main issue in this appeal, therefore, is the effect of the proposed increase in the length of the proposed dormers on the character and appearance of the host property and the surrounding area.

The appeal property (No 112) is one of a group of 5 detached bungalows of similar design. No 112 has gable ended roof profiles projecting from front to rear. It reflects the original appearance of both neighbouring bungalows which have since been extended and altered, including by the installation of side dormer windows which run along the length of their original roofs.

The extended dormers would be located below the ridge tiles, an element of the original and extended roof slopes above the eaves line would be retained and they would be set in 1m from the rear elevation of the first-floor extension. The dormers would therefore remain within the roof profiles. The additional length of the dormers would be proportionate to the size of those that have previously been approved and would be proportionate to the bungalow as it would be extended. The larger dormers would be sufficiently subservient to the scale of the existing roof.

No [address] (No 114) projects about 2m further forwards than No

This creates a staggered building line in which the flank elevation of No 112 is largely screened by the massing of No 114. The rearmost part of the already approved dormer windows would be screened from public views due to the orientation of the bungalows and the road. It follows therefore that views of the additional dormer length towards the rear of the building would also be limited. But in any event, whilst the bulk and mass of No 112 would increase, the proposed development would not appear incongruous in the context of the neighbouring bungalows, despite the differing length of their dormers.

When the Council considered the previous planning application, it accepted that the scale of the dormers was not fully compliant with Policy DMHD 1 of the Hillingdon Local Plan: [name] - Development Management Policies (2020) (HLP2 DMP). However, officers considered that the character of the group of bungalows had already changed, and that the proposal would ensure an element of design consistency. The Council concluded that the conflict with policy was outweighed by consideration of the character of the surrounding area. Similarly, the development proposed in this appeal would not fully accord with the technical requirements of Policy DMHD 1. However, in my judgement this continues to be outweighed by the absence of harm to the appearance of No 112 and to local character.

Overall, I conclude that the longer dormers would harmonise with the architectural composition of the dwelling as it is proposed to be extended. In views from the public realm, the proposal would reflect the design of neighbouring properties with side dormers and would respect the pattern of development in the locality. As there would be no harm to the character and appearance of the host bungalow, the street scene or to or the wider surrounding area, the proposal would comply with Policy BE1 of the Hillingdon Local Plan: [name] - [name] (2012) and [name] 11, DMHB 12 and DMHD 1 of the HLP2 DMP.

For the reasons set out above and having regard to all other matters raised, the appeal is allowed subject to the conditions that follow.

The necessary conditions are the same as those imposed on the previous approval referred to above, with the exception of conditions relating to an outbuilding which does not form part of this appeal.

I have included a condition identifying the approved drawings for the avoidance of doubt and in the interests of proper planning. Matching external materials are required to protect visual amenities. No openings shall be constructed in the walls or roof to prevent overlooking and to protect the living conditions of the neighbouring occupiers. For the same reason, the dormer windows facing onto Nos 110 and 114 are required to be obscurely glazed and partially non-opening, and the use of the flat roof is also prevented.