Appeal 3272367

The appeal is dismissed.

The Council’s reason for refusing the application refers to Policies 3.5 and 7.4 of the London Plan (2016), which relate to the quality of design of housing developments and the contribution that development makes to local character. That plan has since been superseded by the London Plan 2021 (LP) published in March 2021. Policy D3 of the LP sets similar requirements for development with respect to the quality of design and how it responds to local character and the need to ensure appropriate amenity, and policy D6 sets out the design standards for new housing development. I have therefore determined the appeal with regard to Policies D3 and D6 and am satisfied that neither party will be caused an injustice by taking this approach.

The main issues are the effect of the proposed development upon: • the character and appearance of the host dwelling and area; • the living conditions of occupants of the building and host dwelling, with particular regard to garden space, outlook and privacy, and that of occupants of neighbouring dwellings with particular regard to outlook and light; and, • highway safety, with regard to the adequacy of parking provision.

The proposed development would involve extensive alterations to an existing store at the rear of the appellant’s garden. The store is currently built on the boundary with neighbouring properties to the side and rear. The rear wall and at least one side wall would be brought in from the boundary and the front wall would extend forward of the existing building line into the garden, although overall the building’s footprint would only marginally increase. The proposed pitched roof that would replace the flat roof would be approximately 2 metres higher.

The appellant states that the proposal is for use as ancillary accommodation for her mother in law. I have no evidence to suggest otherwise. The annex would be smaller than the main house and share utility connections, garden space and have a shared boundary with it. I am therefore satisfied that the proposed development would be ancillary to the main house.

Nonetheless, the proposal would conflict with Policy DMHD 2 of the Hillingdon Local Plan Part Two - Development Management Policies (January 2020) (DMP) which does not permit outbuildings to contain a bedroom, bathroom or kitchen. The supporting text to the policy also states that the Council will strongly resist development that would result in an over dominant and visually obtrusive form of development.

Several properties in the vicinity of the appeal site, including a neighbouring house, have single storey outbuildings at the rear of their gardens. They include wooden buildings with shallow pitched roofs. However, the proposed building would sit forward of the existing building and the neighbour’s outbuilding, and its roof would be substantially higher. Whilst remaining subservient to the main house it would appear dominant and visually intrusive compared to other outbuildings in the vicinity. Although it would not be visible from the street, it would be seen from the rear of properties along [name] and [name] which backs onto it. From these views it would have an adverse effect on the character and appearance of the area and thus conflict with Policy DMHB 11 of the DMP and Policy D3 of the LP which require development to integrate with local character taking into account the height of adjacent structures and building and roof lines. Policy DMHB 12 of the DMP deals with the impact of development on the public realm and given the appeal site’s rear garden location is not directly relevant to this issue. Living conditions.

The proposed unit would fail to meet the minimum required standard for internal floorspace as set out in the Department of Communities and Local Government’s Technical Housing Standards–nationally described space standards (March 2015), which informed the space standards in the London Plan, the Mayor of London's adopted Supplementary Planning Guidance - Housing (March 2016) (SPG) and Policy DMHB 16 of the DMP. This is acknowledged by the appellant. Nevertheless, the open plan bedroom/living space exceeds the size requirements for a bedroom and the shower/toilet is adequately sized. When combined with access to facilities in the main house, I am satisfied that the functional needs of future occupants would be capable of being met.

The proposed development would be at the rear of the appeal site and whilst taller than the existing outbuilding would not lead to any significant increase in overshadowing or reduction in daylight to neighbouring gardens or houses. Whilst it would be visually intrusive in terms of the character and appearance of the area, it would not appear overbearing when viewed from neighbouring properties to the extent that it would harm occupant’s living conditions. 10.I accept that a degree of mutual overlooking is to be expected between gardens, outbuildings, and neighbouring houses, as suggested by the appellant. However, where outbuildings would be used as accommodation, privacy and outlook are important considerations. The rear first floor windows of neighbouring houses would face onto, and would be less than 15 metres from, the proposed annexe kitchen window and bi-folding glass doors serving the living room/bedroom. This would lead to overlooking and an unacceptable loss of privacy for occupants of the proposed annexe. Also, the rear ground floor extension of the host dwelling would be less than 8 metres from the proposed annexe windows. This distance would not allow for the level of privacy that the occupants of the proposed development and host property might reasonably expect, even if they are from the same household. At this distance the host property would also appear unacceptably dominant and overbearing when looking out from the proposed living room and kitchen window. The appellant’s suggestion that a planted screen might reduce the potential for overlooking would further harm the outlook from the proposed annex and reduce the useable garden space. 11.Policy DMHB 18 of the DMP sets size standards for private outdoor amenity space for residential properties based on bedroom numbers. The proposed annexe would effectively add another bedroom to the host property. However, I have no indication of the existing number of bedrooms and whether the relevant standard is currently met, or whether the size requirement would increase because of the proposed development. In anycase, I do not consider that the small reduction in the size of the rear garden that would result from the proposed development would, on its own, be a reason to withhold planning permission. 12.Overall, I conclude on this main issue that the proposed development would have an unacceptable adverse impact on the living conditions of future occupiers of the proposed annexe regarding outlook and privacy, and to the host dwelling regarding privacy, and would therefore conflict with Policy DMHB11 of the DMP, Policy D3 of the LP and the SPG which require development to incorporate principles of good design and deliver appropriate outlook, privacy, and amenity. Highway safety 13.A hard standing at the front of the host property provides off street parking which could accommodate 2 cars and would meet the car parking requirements for a 3 or more bedroom house set out in policy DMT 6 and [name] 1 of the DMP. As such, the proposed development would have no impact on highways safety and would accord with policy DMT 2 of the DMP which requires that development proposals should not reduce the safety of road users and residents.