Appeal 3340032

The appeal is allowed and planning permission is granted for loft conversion consisting of 3 number gabled dormers. Side extension to right hand side of building; offset away from the neighbouring boundary at [site address] , Downe, Kent [postcode] in accordance with the terms of the application, [name]/23/03073/FULL6, and the plans submitted with it, subject to the conditions in the attached schedule.

Section E of the appeal form confirms that the description of the development has changed from that stated on the application form and the Council’s Decision Notice refers to a different description of development. However, I have not been provided any confirmation of an agreement between the parties to change the description of development. I have, therefore, used the original description from the planning application form in my banner heading above.

At the time of my visit, I observed the development to be at an advanced stage of construction.

The main issues are: i) whether the proposal would be inappropriate development in the Green Belt having regard to the development plan and the National Planning Policy Framework (the Framework); ii) the effect on character and appearance; and iii) the effect on the living conditions of the occupiers of the neighbouring property by reason of outlook.

The Framework identifies that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. It goes on to state that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. The Framework further establishes that the construction of new buildings in the Green Belt should be regarded as inappropriate, subject to a number of exceptions as set out in paragraph 154 of the Framework. One such exemption being the extension or alteration of a building provided that it does not result in disproportionate additions over and above the size of the original dwelling. Policy 49 of the London Borough of Bromley Local Plan 2019 (BLP) broadly conforms to the general thrust of national Green Belt policy in this regard.

Policy 51 of the BLP supports extensions or alterations to dwellinghouses in the Green Belt subject to three provisos; one of which states that extensions which comprise development which is over 10% of the original floor area will not normally be permitted in Green Belt. This policy is more prescriptive than the Framework which does not provide a definition of ‘disproportionate additions’. Whilst floorspace calculations can be used as a guide to determine whether a proposal would be a disproportionate addition, in my view, it is a matter of planning judgement and cannot be solely based on a statistical set of indicators. I therefore afford moderate weight to Policy 51.

The Council officer’s report estimates the additional level of accommodation to represent a 50.4% increase in useable floorspace. In calculating the proposed increase, the Council has included the floorspace of the existing loft rather than solely the floorspace created by the dormer windows and single storey extension. The policy, nor its supporting text, clarify whether existing loft space can be counted in a calculation of any net increase. However, from the evidence before me, this would not be consistent with the Council’s previous approach in assessing a loft conversion at the appeal site1. I concur that it would be reasonable to exclude the original floorspace of the loft as this forms part of the original dwelling. In this regard the appellant submits that the additional floorspace created would equate to a 22.5% increase from the original building.

Whilst the floorspace created would exceed the 10% threshold stipulated by the development plan policy, having a broader judgement of what represents a disproportionate addition, in my view the proposed development would not amount to such.

Consequently, I conclude that the proposed development would not amount to a disproportionate addition over and above the size of the original building, and that therefore the proposal would not represent inappropriate development in the Green Belt. Some tension would arise with the restriction within BLP Policy 51 with regard to floorspace. Nevertheless, I am satisfied that the proposal would accord with the overall aims of Policies 49 and 51 of the BLP, and the Framework, which seek to protect the openness and permanence of the Green Belt and to prevent inappropriate development within it. 1 office reference DC/21/04003/FULL6

The appeal site lies within a suburban context, surrounded by residential development. Accordingly, having regard to Policy 51 of the BLP the appeal site does not have an open or rural character and accordingly I find no conflict in this regard.

[address] comprises an eclectic mix of housing types and architectural design, where there is no consistent pattern of development within the streetscene. At my site visit I observed properties with dormer windows of varying designs and proportions to their front and rear elevations. Owing to the height of these buildings many of the dormer windows, even on the rear elevation of the properties, are highly prominent in the streetscene.

The scale and positioning of the proposed dormers would be proportionate to, and align with, the proposed windows to the front facing ground and first floor of the building and provide symmetry to the design of the front elevation of the proposed building. The materials for the external elevations of the dormer windows would be in-keeping with the existing roof covering which helps assimilate the dormer windows with the roof of the main building. Furthermore, the use of a lightweight materials in the form of an extended glazing panel to the central dormer window would assist in reducing its prominence.

Accordingly, for the reasons stated the proposed dormer windows would not appear unduly prominent or incongruous in the streetscene, particularly when viewed against the backdrop of the rear dormer on the adjoining property and the dwelling immediately opposite the appeal site, which has a similar dormer window arrangement. Accordingly, this element of the proposal would not harm the visual amenities of the locality.

The single storey addition would be subservient to the main dwellinghouse, set back within the plot behind a landscaped frontage. The proposed front facing window would be of a similar proportion to the existing windows and the external finish would be constructed in materials sympathetic to the host property. Given the limited scale of the proposal, and the varied context in which the appeal site lies this, element of the proposed development would not be an incongruous addition to the wider street scene.

Taking all of the above into account, I conclude that the proposal would not be harmful to character and appearance. Accordingly, the proposal would comply with Policies 6, 37 and 51 of the BLP which collectively, among other things seek high quality design that respects the dwelling’s character and appearance that would not harm visual amenity or the open or rural character of the area.

The appeal site adjoins a property which fronts [address] (No 2) whose garden adjoins the shared boundary. A high solid boundary fence forms the boundary between the neighbouring properties.

Whilst the proposed single storey extension would protrude beyond the rear elevation of the adjoining property, the extension would be off set from the shared boundary by approximately 1.7m. Furthermore, the proposal would be of limited height with its roof pitch sloping away from the shared boundary. This, when combined with the presence of an existing high boundary treatment, leads me to conclude that the proposal would not be visually dominant when viewed from the neighbouring garden and ground floor windows.

For these reasons I conclude that the proposal would not harm the living conditions of the occupiers of the neighbouring property by reason of outlook. Accordingly, the proposal would comply with Policies 6 and 37 of the BLP. Collectively these policies seek to protect existing residential occupiers from inappropriate development.

My attention has been drawn to a Lawful Development Certificate (LDC) granted in January 2022 relating to the site2, serving as a ‘fallback’ position for the appellant. I have been provided with a copy of the plans and advised by the appellant that the proposal exceeds the 10% threshold set out in Policy 51 of the BLP. Although lower in height than the appeal scheme, the LDC scheme would be positioned closer to the shared boundary. Moreover, the proposal is of a similar footprint to the extant scheme and, in my view, the pitched roof and glazing to the gable end would be a visual enhancement to the fallback scheme.

I have also been provided with plans for an approval for loft conversion at the appeal property, comprising front dormers and rooflights to the rear, granted by the Council in 20213. The design of the proposal differs, and the appeal scheme and provides for larger dormer windows. However, the appeal scheme would not result in a significant increase in volume from what has already been permitted.

I consider that there is a greater than theoretical possibility that these developments might take place should the appeal fail, and accordingly, the fallback position is a significant material planning consideration in my determination of this appeal.

As the development has commenced, it is not necessary to impose the standard time limit for implementation. A condition to ensure that the development is carried out in accordance with the approved plans is needed for certainty and in the interests of proper planning. A condition stipulating matching materials is needed interests of preserving the character and appearance of the area.

For the reasons given above, the appeal is allowed.

The development hereby permitted shall be carried out in accordance with the following approved plans: Location & Block Plan drawing no JBD/BR6/7HJ/060, [name] & Views: Ground Floor Plan 28/08/2023, First Floor Plan 28/08/2023, Second Floor Plan 28/08/2023, [address] – [name], [address], [address] and [address].

The external surfaces of the development hereby permitted shall be constructed in the materials stated on the planning application form. ***End of Schedule***