Appeal 3278206

The appeal is dismissed.

Notwithstanding the description of development set out above, which is taken from the application form, it is clear from the plans and accompanying details that the development comprises the erection of a dormer roof extension in the rear roof slope of the existing house and rooflights to the front. The Council dealt with the proposal on this basis and so shall I.

The main issues are: • whether the proposed development would be inappropriate development in the Green Belt; • if the proposed development is inappropriate, the effect of the proposed development on the openness of the Green Belt; and • whether the harm by reason of inappropriateness, and any other harm, would be clearly outweighed by other considerations so as to amount to the very special circumstances required to justify the proposal.

The appeal site comprises a two-storey semi-detached property positioned within a reasonably large plot. Similar properties are nearby. The property has been extended previously in the form of a side extension, rear conservatory extension and porch. Although located outside of the defined settlement boundary, No [site address] is contiguous with the extended built form of the village of Crockenhill as it appears on the ground.

The appeal property would be extended at roof level, through the construction of a dormer roof extension within the rear roofslope of the main house, with rooflights to the front. Materials would match those of the existing house.

Policy GB1 of the Sevenoaks District Council Allocations and Development Management Plan (2015) (LP) in summary, amongst other things, supports the limited extension or alteration of existing dwellings where this would be small scale compared to the original dwelling. Paragraph 147 of the Framework sets out that inappropriate development is, by definition, harmful to the Green Belt and should not be approved ‘except in very special circumstances’. In a similar manner to the LP policy referenced above, one exception to that position is the extension or alteration of a building, provided that it does not result in disproportionate additions over and above the size of the original building.

The Framework does not provide a definition of ‘disproportionate additions’ However LP Policy GB1 sets out that the design of extensions should be visually proportional and subservient to the original dwelling, which in my view are local considerations. In addition, Policy GB1 specifies the total floor space proposed, together with any previous extensions or alterations, should not result in an increase of more than 50% above the floorspace of the original dwelling. In my view, such a metric may only realistically be an approximation for disproportionality, not least because of the absence of such a metric in the Framework, and as proportionality is inherently context specific.

As noted above, the appeal property has been extended on several occasions, significantly increasing the total floorspace of the property over time. This includes the addition of a rear extension, side extension and porch. These elements are not original as they were constructed after 1 July 19481.

There is some dispute between the main parties as to whether the existing attached garage was in existence on or before 1 July 1948, and whether it is therefore original or not. Based on the Council’s calculations, the garage is not original and was added at a later date. The Council estimates the proposed development, combined with those existing extensions, would result in an increased floorspace of 188.49sqm, a 95.85% increase over the original dwelling.

The appellant, on the other hand, estimates that the proposed extension and existing extensions, with the garage assumed not to be original, would take the figure marginally over a 50% increase relative to the original dwelling. The appellant also sets out that if the garage was deemed to be original, the figure would be below a 50% increase and therefore accord with LP Policy GB1. This is based on the appellant’s assumption that the proposed dormer would add a floor area of 4sqm.

Whilst these arguments are acknowledged, there is no clear evidence to confirm that the garage is original. Moreover, I note that within the planning history section of the officer report, there is reference to planning permission at the site for an attached domestic garage dating from 19752. [name] cannot categorically conclude that this relates to the garage that exists at the site, it does, in all likelihood and based on my site observations, appear to form planning permission for that garage. 1 As defined within the Framework definition of ‘Original building’ and LP Policy GB1. 2 Ref 75/01510/HIST

Furthermore, it is a requirement of LP Policy GB1 that the applicant provides clear justification of how the proposal complies with the policy in respect of floorspace, together with detailed floor space calculations. I have no such evidence before me. Based on the evidence I do have before me, it is highly likely that the garage is not original and would therefore need to be considered as additional floorspace relative to the original dwelling.

Turning to the roof, LP Policy GB1 explains that planning applications that include the conversion of loft space through the addition of only roof lights will not be subject to the 50% floorspace allowance, provided there is no increase in volume or bulk. However, it states that proposals for loft conversions that include the addition of dormer windows that do create volume or bulk will be subject to the 50% allowance. Albeit that external physical changes are limited, in my view they would nonetheless result in a building which is perceptively more bulky on account of the changes to the roof proposed (as opposed to more consistent with its original roof form and arrangement).

The proposed development would introduce a dormer window which protrudes from the existing roofslope, enabling the conversion of the roofspace. The Council takes account of the entire floorspace of the roof created through the proposed development, reaching a figure of 33.44sqm. I have no reason to disagree with that methodology based on the wording of LP Policy GB1.

On the basis of the garage not being original, the overall increase in floorspace, including loft conversion, would be well in excess of a 50% increase on the original dwelling. If the appellant’s figure of 4sqm was used, this increase would still tip the overall increase in floorspace over 50% of the original dwelling, a point which they have stated in their own submission. Even were the garage original, the Council’s estimated 33.44sqm created through the loft conversion, together with rear, side and porch extensions, would exceed the size of the garage and all original elements, failing to accord with Policy GB1.

My attention is drawn to previous planning consents3 and an historic dismissed appeal decision4 at the same site. The appellant notes that the previous consent for extensions sets out that the development at the time was appropriate within the Green Belt and was not disproportionate. It is set out that the refused consent, later dismissed at appeal, was not for Green Belt reasons. I do not have the full detail of these cases before me. However, the lack of harm identified under these previous decisions does not automatically mean that the proposed development before me is acceptable. The context of the site has changed through the implementation of extensions and I have considered the development on the evidence presented, and site observations.

Taken together, the total floorspace increase as a result of the proposed development would be inappropriate development in the Green Belt which is, by definition, harmful. The proposed development would therefore conflict with the relevant provisions of LP Policy GB1, which in summary seeks to limit extensions to dwellings in the Green Belt. This is consistent with the Framework in so far as development in the Green Belt is concerned. 3 Refs 10/02834 and 11/01341 4 [name]/G2245/A/D/11/2143607

The Framework indicates that openness is an essential characteristic of the Green Belt and a fundamental aim of Green Belt policy is to keep land permanently open.

The openness of the Green Belt, in my view, has both a physical and visual dimension. ‘Open’ can mean the absence of development in spatial terms, and it follows that openness can be harmed even when development is not readily visible from the public realm.

The appeal property is very clearly visible from the adjacent highway and neighbouring properties, and notwithstanding the existence of other two-storey properties near to the appeal site, the openness of the Green Belt is readily apparent beyond.

[name] accept that the extension to the dwelling is fairly limited in scale and has been designed with sensitivity to prevailing building forms, materials and detailing, it would nonetheless result in built volume and massing where this does not presently exist. The additional bulk of the dwelling as a result of the proposed development would inevitably lead to a loss of openness, both physically and visually. Accordingly, the proposed development would cause harm to the openness of the Green Belt. This factor weighs somewhat against the proposal.

The appellant argues that something similar to the scheme may be achievable generally under permitted development. Nevertheless, permitted development rights were withdrawn in respect of the appeal property via condition on a pervious permission (setting aside any argument as to whether that was appropriate, it nonetheless occurred). Consequently, there is no realistic fallback position before me.

I accept that the proposed development would enhance the living conditions of the occupiers of the property, providing them with a further accommodation. However, the increased use of the existing living accommodation is essentially a private benefit rather than the public planning harm that would result. I have no substantive evidence before me in respect of the sustainability benefits claimed by the appellant, nor that any are inherently reliant on the specific scheme before me.

The appellant has set out that the Council cannot presently demonstrate a five year land supply of deliverable housing sites and that the provisions of Paragraph 11d of the Framework should be engaged. The Council has not disputed this shortfall. However, this is not a scheme for the provision of housing, and it would not contribute to housing supply in the area.

Consequently, other material considerations in favour of the proposal do not justify taking a decision contrary to the development plan.

The proposed development would be inappropriate development in the terms set out by the Framework and would result in harm, albeit limited, to the openness to the Green Belt. The Framework nonetheless requires that substantial weight should be given to any harm to the Green Belt.

The harm identified would not be outweighed by the other considerations and, therefore, the very special circumstances necessary to justify the proposed development do not exist. Consequently, the appeal is dismissed.