Appeal 3336539

The appeal is dismissed.

A revised version of the National Planning Policy Framework (the ‘Framework’) was published in December 2023, but there are no material changes relevant to the substance of the appeal.

The building the subject of this appeal was substantially complete at the time of my site visit and I have determined the appeal on this basis.

The main issues are the effect of the appeal proposal upon: the character and appearance of the area; the living conditions of the existing and future occupants of the host dwelling; and the living conditions of the occupants of neighbouring residential properties, with specific reference to light and outlook.

The proposal comprises a pitched roof outbuilding with a total floor area of just under 20sqm constructed within the rear half of a modest garden serving the appeal dwelling.

The majority of houses within the terrace have original small timber sheds within their gardens, although some of these have since been removed, and in the case of [address] has been replaced by a quite substantial mono-pitched structure. No 7 is however on the end of the terrace and is located within a slightly larger plot, therefore whilst there are similarities between this and the appeal scheme, there are also differences; and ultimately each case must be assessed on its own merits.

No 11 adjacent to the north, has a single storey rear extension in close proximity to the appeal building, the outlook therefrom is impeded by the subject building to some degree.

I note that the eaves of the outbuilding are below the maximum 3m advocated by the Council’s Residential Extensions Guidelines Supplementary Planning Document (REG) and that its height at 3.75m would also comply with the REG. However, that document does stipulate that within 1m of the boundary of a property, steps should be made to reduce its height, such as the introduction of a hipped roof.

By virtue of the density of the terrace of which the appeal site forms part, in addition to the development to the rear (west) at [address], which tend to have shallower rear gardens, it is imperative that any such proposals minimise their impacts upon the living conditions of the occupants of surrounding residential properties.

Views of the outbuilding would in the main be restricted to private views from within the rear garden scene, but nonetheless by virtue of its overall scale it creates an imposing feature being significantly larger than the aforementioned timber sheds within adjacent rear gardens.

The REG also highlights that the retention of good quality, usable amenity space is considered to be essential to ensuring that properties be of the highest quality internally and externally, and whilst paragraph 3.6 as set out therein makes explicit reference to extensions, as opposed to outbuildings, nonetheless in its second paragraph it stipulates that should a proposed outbuilding reduce the rear garden area of a property to below the area equal to the footprint of the original dwelling, that an application would be at risk of refusal.

The Council stipulates that the footprint of the original house is approximately 44 sqm and the appellant does not dispute this calculation. Consequently, the remaining rear garden measures approximately33 sqm, thereby significantly diminishing the usable private amenity space available to both existing and future occupiers of no10. Combined with its sheer visual presence I consider that by virtue of its overall scale, the scheme diminishes the usable private amenity space, which not only causes harm to the character of the area, but also to the aforementioned living conditions of existing and future occupants.

I say this notwithstanding that the site does not fall within a designated heritage asset and in itself it is subordinate in form when compared to the host dwelling. I acknowledge that the purpose and function of the building as a garden room provides a dry environment incidental to the enjoyment of the garden and whilst I acknowledge that it could quite clearly be used as a place of relaxation, respectfully, it appeared as an extension to the internal living accommodation of no10 as opposed to being a practical workspace for horticultural purposes. Further, bearing in mind the extremely limited area of garden retained, I doubt that there would be much need for the preparation and planting of greenery within the building or garden itself.

In terms of neighbouring impacts, by virtue of the building’s orientation in relation to that of no 11, it would quite likely cast a shadow upon that dwelling’s rear garden and rear habitable room windows at ground floor level from around midday onwards. Also, due to the aforementioned close proximity of the 2 outbuilding to the extension on the rear of no11, the outlook therefrom is also quite significantly curtailed. No [address] has a very shallow rear garden of only just over 5m deep and therefore notwithstanding the aspects of the scheme that comply with the REG, with the outbuilding spanning the majority of the rear garden boundary of that neighbouring property, outlook from it would also be significantly restricted. The outbuilding is also visible from the rear of [site address] , although on balance, notwithstanding the visual imposition of the structure, it would unlikely give rise to a material level of harm to the living conditions of the occupants of that neighbouring property.

Therefore, in conclusion, I consider that the proposal causes demonstrable harm to the character and appearance of the rear garden scene, significantly undermines the area of external private amenity that serves the host dwelling and also would give rise to demonstrable loss of outlook from [address] and [address] with a high degree of overshadowing also created over the rear garden and rearward facing ground floor windows of the former. 16.In addition to conflict with the REG, I also find the proposal contrary to Policies CC1, CC2 and SC7 of the London Borough of Hounslow Local Plan 2015 – 2030 which seeks to ensure that all new development conserves and takes opportunities to enhance the special qualities of the Borough’s places by securing development that sensitively and creatively responds to an area’s character by refusing poor quality design to create attractive, distinctive and liveable places, complement the original building, harmonise with adjoining properties and maintain the character and amenity of private spaces (including rear gardens), as well as minimising harm to neighbouring residents such as avoiding an unacceptable loss of daylight / sunlight, outlook or by creating an unacceptable sense of enclosure. Further, the latter policy also requires proposals for outbuildings to not overdevelop a site in terms of mass and density.