Appeal 3296465

The appeal is dismissed.

The description of development in the heading above has been taken from the planning application form. [name] of the appeal form it is stated that the description of development has not changed but, nevertheless, a different wording has been entered. However, neither of the main parties has provided written confirmation that a revised description of development has been agreed. Accordingly, I have used the one given on the original application.

The main issues in this case are: • Whether the proposal would be inappropriate development in the Green Belt having regard to the National Planning Policy Framework (the Framework) and any relevant development plan policies; • The effect of the proposed development on the openness of the Green Belt; • The effect of the proposed extensions on the character and appearance of the existing property and the surrounding area; • The effect of the proposal on the living conditions of the occupiers of the neighbouring property at Wykenham in Brookshill, with particular reference to outlook, daylight and sunlight; and • Whether any 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 property is located in the Green Belt. Paragraph 149 of the Framework regards the construction of new buildings as inappropriate in the Green Belt, subject to a limited number of exceptions. One of those exceptions 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 term ‘original building’ is defined in Annex 2 of the Framework, as the building as it existed on 1 July 1948 or, as it was originally built, if constructed after that date. The appellants’ evidence confirms that the original house at Roxey was built in 1949, and that the single storey rear extension, garage and other outbuildings have been added since and, as such, do not form part of the original building.

Based on the calculations provided by the appellants, excluding the single storey rear extension, garage and outbuildings, the overall volume of the original building is 346.41 cubic metres (m3), its floorspace 106.[address] metres (m2), and its footprint 52.7 m2. The volume of the proposed extensions would be 399.95 m3, their floorspace 115.57 m2 and their footprint 87.04 m2, again based on the appellants’ calculations. As such the proposed extensions would amount to an increase in the size of the original building of 115% of its volume, 108% of its floorspace and 165% of its footprint.

I note that the proposed extensions would only result in a 26% increase over and above the volume of the existing buildings on the site, taking into account the proposed removal of the single storey rear extension, garage and outbuildings. These may be material factors in determining the effect of the proposed development on the openness of the Green Belt and in assessing whether very special circumstances exist in this case, which I deal with separately below. However, in determining whether the proposed extensions would be inappropriate development in the Green Belt, under paragraph 149(c) of the Framework, the test is whether or not they would result in disproportionate additions over and above the size of the original building, not the existing buildings.

The proposed extensions would more than double the size of the original building, whether calculated by volume, floorspace or footprint. Whilst national and local planning policies do not provide a measure of what constitutes a disproportionate extension, the proposals would substantially exceed a 30% increase, which is used by the Council as a rule-of-thumb for what is considered to be a proportionate increase in the size of buildings within the Green Belt. The side extensions would also increase the width of the original building by more than 50%. By all of these metrics, I consider that the proposed extensions would result in disproportionate additions over and above the size of the original building.

Accordingly, I conclude that the proposal would be inappropriate development in the Green Belt. Paragraph 147 of the Framework states that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances.

Paragraph 137 of the Framework states that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open, and that openness is an essential characteristic of the Green Belt. The Courts have confirmed that openness has both spatial and visual aspects.

In spatial terms, the proposed development would result in an increase in the volume of built development on the site. Whilst the net increase would only be 26% over and above the volume of the existing buildings on site, nevertheless there would be an overall increase in the amount of building and a consequent spatial reduction in the openness of the Green Belt in this location.

In visual terms, the proposed extensions would increase the width, depth and overall bulk of the existing house and thereby reduce the space around the dwelling. The existing outbuildings to be removed are single storey, dispersed around the plot, and all except two are unseen from the street. The proposed extensions would bring that volume together and add it to the existing dwelling, including at first floor level, so that the visual impact of the proposal on openness would be significantly greater than the existing buildings on site.

This would be most evident in the view of the front of the property from Brookshill. The gap at the side of the dwelling is currently only occupied by a detached single width garage, above which it is possible to see the openness of the plot to the rear of the house and the wooded backdrop to the property. The proposed ground and first floor side extensions would effectively extend the house across the width of the plot, closing up the gap at the side of the property and the vista through to the open space at the rear.

In these ways the proposal would increase the spatial and visual impacts of urban development at the appeal property, thereby reducing and causing harm to the openness of the Green Belt in this location. As such, it would be contrary to the fundamental aim of Green Belt policy in paragraph 137 of the Framework.

Roxey forms one of a pair of two-storey, semi-detached houses with Wykenham its adjoining neighbour to the north. The house itself is modest in size, but sits on a large plot, with plenty of space around it, being set well back from the road frontage and around 4-5 metres (m) in from the side boundary with [address] to the south. The surrounding area has a spacious, wooded character and appearance, and in its current form, Roxey contributes and is sympathetic to that character.

Paragraphs 6.45-6.50 of the [name] (2010) (RDG) provide guidance on the design of first floor and two-storey side extensions to detached and semi-detached properties. I acknowledge that the proposed first floor side extension would be a least 1 m from the side boundary, and that this and the variation in the building line along this part of Brookshill would justify the absence of 1 m set-back from the front wall of the existing house, in accordance with paragraph 6.47 of the RDG.

However, paragraph 6.45 of the RDG makes clear that the primary design considerations for such extensions are the character of the locality and the space around the building. In this case, the effect of the proposed development in extending the house substantially across the width of the plot and closing up the gap at the side of the house would fail to respect the space around the existing property and its contribution to the street scene in this part of Brookshill.

On this basis, the appeal proposal would cause unacceptable harm to the character and appearance of the existing property and the surrounding area. Accordingly, it would be contrary to Policies D3.D(1) of The London Plan (2021), CS1.B of the [name] (2012) (the CS) and DM1 of the Harrow Development Management Policies (2013) (the DMP), all of which seek to resist development which would be detrimental to local character and appearance. It would also fail to accord with Paragraph 130c) of the Framework which expects development to be sympathetic to local character.

The proposed single storey rear extension would abut the shared boundary with Wykenham. It would project 4 m from the rear wall of the existing house and rise to a height of 3.5 m at the crown of the roof for 3 m along the boundary. Paragraph 6.25 of the [name] expects that extensions should not cause any unreasonable loss of light or overshadowing to any habitable rooms in neighbouring properties.

Wykenham has a bay window to a main habitable room at ground floor level close to the boundary. Due to the height and length of the proposed rear extension and its position directly to the south of the bay window, it would result in a significant loss of light to the room served by the bay window and have an overbearing effect on the outlook from that room.

I recognise that The Town and Country Planning (General Permitted Development) (England) Order 2015 would permit an extension of 3 m in depth and 3 m in height in the same position. However, as a fallback scheme this does not justify the proposed rear extension, which would exceed these dimensions and, based on the evidence before me and my observations on site, cause an unreasonable degree of overshadowing and loss of light to the neighbouring property.

I also note that occupiers of Wykenham are seeking to extend their property in a similar manner at the rear, but that proposal is not before me and the [name] does not provide a guarantee that it would come forward. Therefore, I can attach little weight to this in mitigation of the effects of the appeal proposal on the current living conditions at Wykenham.

Accordingly, I conclude that the appeal proposal would cause unacceptable harm to living conditions of the occupiers of Wykenham, with particular reference to outlook, daylight and sunlight. Consequently, the proposed development would be contrary to Policies D3.D(7) of the London Plan and DM1 of the DMP, which seek appropriate outlook and amenity, and resist proposals that would be detrimental to the amenity of neighbouring occupiers. It would also conflict with paragraph 130f) of the Framework, which expects a high standard of amenity for existing and future occupiers.

The appellant contends that the removal of all of the existing outbuildings and structures on the site would amount to an overall improvement to the site, and form ‘very special circumstances’ to justify the approval of the proposed extensions. I acknowledge that the loss of the existing outbuildings would improve the appearance of the site, to which I attach a small amount of weight as a benefit from the proposal. But, as there would still be an overall increase in the volume of buildings on the appeal site, which I have concluded above would harm the openness of the Green Belt, the removal of the existing outbuildings does not carry any weight in favour of the appeal scheme, in terms of its overall impact on the fundamental aim of the Green Belt.

The proposed extensions would be inappropriate development, which the Framework states is harmful to the Green Belt and should only be approved in very special circumstances. They would also cause harm to the openness of the Green Belt, albeit this would be limited given the scale of the proposal in relation to the London Green Belt as a whole. However, paragraph 148 of the Framework establishes that substantial weight should be given to any harm to the Green Belt. In addition, I attach significant weight to the harm the proposed development would cause to the character and appearance of the property and surrounding area and to the living conditions of the occupiers of Wykenham.

The proposed removal of the existing garage and outbuildings would be a benefit, but not of sufficient magnitude as to outweigh the harm to the Green Belt and the other harms that I have identified. Consequently, the very special circumstances necessary to justify the proposal as inappropriate development do not exist. Accordingly, the appeal proposal would be contrary to Policies G2 of the London Plan, CS1.F of the CS and DM16 of the DMP, all of which seek to protect the Green Belt from inappropriate development, and to paragraphs 147 and 148 of the Framework.

For the reasons given above, and taking account of all other matters raised, I conclude that the appeal should be dismissed.