Appeal 3286003

The appeal is dismissed.

An application for costs has been made by [name] against Dorset Council. This application is the subject of a separate decision.

The appeal site is located within 400 metres of the Parley Common Site of Scientific Interest (SSSI). The SSSI forms part of the Dorset Heaths Special Area of Conservation, the Dorset Heathlands Special Protection Area and the [name], which shall collectively be referred to in this decision as the [name]. The Dorset Heathlands are, amongst other provisions, afforded protection under The Conservation of Habitats and Species Regulations 2017 (Habitat Regulations), as they are host to numerous protected priority habitats.

The main issue is the effect of the proposal on the integrity of the [name].

The Dorset Heathlands Planning Framework 2020-2025 (SPD), which was prepared with advice from Natural England, prescribes certain development that may be permitted within 400 metres of the [name] ([name]), without it adversely affecting the integrity of these protected areas. Whilst ancillary residential accommodation, including granny annexes, can be permitted in certain circumstances, the [name] is clear that any development which leads to a net gain in residential dwellings is not permitted within an [name]. This is because there is no effective mechanism to reduce or mitigate the potential adverse effect of additional residential recreational pressures (or predation from domestic animals).

In this instance, the proposed development seeks to convert a detached garage within the appeal site to annexe accommodation. Although the appellant intends for the annex to be used in conjunction with the main dwelling, the garage is located at the rear of a large garden to the main house, which means there is a significant degree of separation between the two buildings. Indeed, a fence has previously separated the garage and associated parking area from the rest of the appeal property, which indicates that the two buildings have functioned somewhat independently from one another in the past. Although the fence has since been removed, there is nothing to indicate that a similar boundary treatment would not be erected in future.

The potential for the annexe to be occupied independently would be exacerbated by the access arrangements to and from the appeal property. The garage already benefits from its own separate independent access from [address], together with its own driveway/parking area. Irrespective of the appellant’s intended use, this separate access and parking arrangement could again facilitate independent use of the annexe, without any reliance on the main dwelling (noting that under permitted development rights, residential outbuildings must be incidental to the enjoyment of a dwelling house).

Moreover, the proposed annexe would be substantial in footprint and would include a bedroom, bathroom and living space. Whilst no kitchen is proposed, works affecting only the interior of a building would not constitute “development”, and so nothing would prevent kitchen facilities from being implemented at a later date. Indeed, the footprint of the garage would exceed the nationally described space standards for a single-storey one bedroom dwelling, which means there would be sufficient space within the annexe to accommodate all the facilities typically associated with a standalone dwelling.

On account of these factors, the proposed annexe would be capable of functioning independently, and irrespective of the appellant’s current intention, would therefore be tantamount to a standalone dwelling. Unfortunately, I do not consider that the risk of such independent use could be properly addressed through the imposition of a condition, as such a condition would be unenforceable given the lack of any readily identifiable action that would denote independent use.

On this basis, and as per the provisions of the SPD, the proposal would risk significant adverse effect to the integrity of the SSSI and the [name], due to the increased intensity of use that is associated with a net increase in residential dwellings. In such circumstances, the Planning Practice Guidance requires me to take an appropriate assessment1, an approach I have applied proportionately, with regard to Natural England’s representations on the proposal and its contribution to the SPD. In this instance, given the location of the proposal within the [name], and in the absence of any mitigation, I cannot conclude that potential adverse effects can be ruled out.

On this basis, and having regard to the conservation objectives set out in the SPD, the proposal would risk adverse effects to the ecology of the [name]. The development would therefore conflict with Policy ME2 of the Christchurch and East Dorset Local Plan (2014), which seeks to ensure new development properly safeguards the protection of the [name]. The development would also conflict with the Habitats Regulations and the 1 [name]: 65-001-20190722 provisions of the Framework (2021), both of which afford stringent protections over designated sites.

[name] acknowledge the development would benefit the appellant in terms of additional living space, this would be a private benefit, and would not outweigh the potential harm it would cause to the integrity of the [name]. Similarly, no alternative solutions, mitigation or other reasons of overriding public interest have been proposed which would outweigh this harm.

The proposal would conflict with the development plan as a whole and there are no other considerations, including the provisions of the Framework, which outweigh this finding. Therefore, for the reasons given, the appeal should be dismissed.