Appeal 3310969

The appeal is dismissed.

The site address on the application form is slightly out of order. The site is in Pinner, which is within the London Borough of Harrow. I have used the correctly ordered address on the Council’s Decision Notice in the banner heading above.

The main issues are: • Whether the proposal would be inappropriate development in the Green Belt having regard to the National Planning Policy Framework 2021 and relevant development plan policies; • The effect of the proposal on the openness of the Green Belt; • The effect of the proposal on the character and appearance of the [address] Estate Conservation Area; and, • If the development is inappropriate, 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 National Planning Policy Framework 2021 (the Framework) states that the construction of new buildings in the Green Belt should be regarded as inappropriate, subject to a number of exceptions. These include the extension or alteration of a building provided that it does not result in disproportionate additions over and above the size of the original building1.

The Council’s Decision Notice lists a number of policies in the development plan which it considers support its contention the proposal is inappropriate development in the Green Belt. Policy G2 (London’s Green Belt) of the London Plan2 re-affirms the approach to inappropriate development contained in the Framework.

Policy CS1(B) of the [name] 2012 (HCS) provides policy direction in terms of Local Character; Policy DM1 (achieving a high standard of development) of the Development Management Policies 2013 (DMP) also provides policy direction regarding Design and Layout. I have considered these policies insofar as they relate to the assessment of whether the proposal would be a disproportionate addition to the original building.

Policy DM16 (Maintaining the Openness of the Green Belt and [name]) of the DMP requires (amongst other things) an assessment of the effect of a development on the openness of the Green Belt to determine whether it would be inappropriate. Such an assessment is not required by paragraph 149 c) of the Framework. Consequently, I have given Policy DM16 very limited and non-determinative weight in my assessment of whether the proposal would be inappropriate development in the Green Belt. I have given the Framework full weight in my assessment.

There is disagreement between the main parties regarding the size of the existing floorspace. From the evidence, including the [name] drawing3 I am satisfied that the existing floorspace at the property is some 166.7m2, and that for the purposes of paragraph 149 c) of the Framework, this is the floorspace of the original building.

The proposed development would increase the footprint of the dwelling by some 6m2 and would add a first floor thereby increasing the total floorspace to some 274m2. This would be an increase of some 107.3m2, or more than 64%, over the floorspace of the original building. This would be a very significant increase and would result in a very substantial change to the appearance of the building. In my view, the scale and massing of the proposal would mean it would be a disproportionate addition to the original building.

I note that the existing dwelling at the appeal site is significantly smaller than nearby dwellings on [address], including the two storey houses next door. I will deal with the effect of the proposal on the character and appearance of the [address] Estate Conservation Area (PHECA) below. However, the size of nearby dwellings is not relevant to my assessment of the effect of the proposed extension on the original building.

For these reasons, the proposal would be inappropriate development in the Green Belt. It would, therefore, conflict with Policy G2 of the London Plan and with the Framework in this regard. 1 Paragraph 149 c) 2 Spatial Development Strategy for [name] 2021 3 Ref. PSH-AP2-102

Openness and permanence are the two essential characteristics of the Green Belt4. The appeal site contains a single storey dwelling set back from [address], within spacious and maturely landscaped grounds, with somewhat larger dwellings also within spacious plots, located nearby.

As set out above, the proposal would slightly enlarge the footprint of the building. Together with the construction of an additional storey this would significantly increase its floorspace. The consequent increase in the scale and massing of the appeal building would mean a reduction in the spatial openness of the Green Belt. Furthermore, this would be visible from [address], a public road, and would, to a very limited extent, also reduce the visual openness of the Green Belt.

For these reasons, the proposal would adversely affect the openness of the Green Belt. It would, therefore, conflict with Policy CS1(F) of the HCS, which concerns [name], Sport and Recreation, with Policy DM16 of the DMP, and with the Framework, in this regard.

The appeal site slopes gently upwards from [address] and contains a detached, single-storey dwelling. The dwelling is set centrally within a spacious garden, containing a lawn at the front, southern side and rear, and mature landscaping, particularly at the rear and along the southern boundary. There is a separate garage/outbuilding to the side of the dwelling, by the northern boundary of the property. The dwelling is of a traditional design and is constructed of bricks with a tiled, pitched roof, containing a curved dormer-type eyebrow window on the southern side and a [name] at the rear.

The appeal site is located on the eastern side of [address], which is an unmarked road with a footpath on its eastern side, by substantial detached dwellings of various designs and sizes and set within maturely landscaped plots. The western side of the road in the vicinity of the appeal site is largely undeveloped and contains mature trees and hedges.

The appeal site is located within the PHECA, the significance of which stems from its historic development, with dwellings of various traditional designs set within spacious and maturely landscaped gardens in the sloping terrain and served by a network of small roads, often lined by mature trees and hedgerows.

Whilst smaller in size than the 2-storey dwellings nearby, the appeal building is of a traditional design and materials and is set-back from [address] within a landscaped garden, which is characteristic of the area. The Council’s Conservation Area Appraisal and [name] 2009 (CAAMS) identifies the existing dwelling as one that preserves the Conservation Area, and I would agree with this assessment.

The extended dwelling would occupy a similar position within the site as the existing dwelling, with substantial areas of garden retained. The materials proposed for the extensions would also match the existing and would be acceptable. 4 Paragraph 137 of the Framework

However, the design of the proposal would see the loss of a number of features that provide visual interest to the existing building, and which are in keeping with the suburban character and appearance of the PHECA, and its historical development. Whilst the existing dwelling is set-back from [address] and partly screened by mature vegetation, several of these features are visible from the street, and would be moreso in late autumn, winter, and early spring.

At roof level, the distinctive ridgelines that follow the form of the building as well as the curved eyebrow window and the chimney stack on the southern roof slope would be lost, as would the distinctive Dutch gable at the rear. These would be replaced by a flat crown roof to replace the main ridge, with flat-topped elements added to the ground floor projections at the front, the sides and at the rear. Roofs with flat topped elements such as are proposed do not respond to the existing building design and are not characteristic of the area.

The visually prominent mock-Tudor gable at the front of the dwelling and the angled bay windows on the southern elevation would be removed, whilst the ground floor fenestration would be changed to a more contemporary design and size. At first floor level the fenestration would follow the approach for the ground floor, emphasising the contemporary and somewhat bland elevations that have little regard to the significance of the PHECA.

The proposal would increase the scale and massing of the dwelling significantly and so the comparatively lacklustre design would be more visually prominent and obtrusive in the streetscene. Whilst 2-storey dwellings on [address] are prevalent, the existing single-storey dwelling has been identified as preserving the PHECA in the CAAMS.

I also note the guidance contained in the CAAMS5, including that ‘...Any extensions will be encouraged to be at the property's rear and subservient in scale to the original property, as well as match the existing house in design....’ And ‘Retain original design features....’ I do not consider the design, scale, massing, and position of the proposal is consistent with this guidance.

In determining this appeal, I have had regard to Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 (as amended). This requires me to pay special attention to the desirability of preserving or enhancing the character or appearance of a conservation area.

Whilst elements of the proposal are acceptable, the proposed design together with the increased scale and massing would detract from the character and appearance of the PHECA and would cause less than substantial harm to this designated heritage asset. No public benefits have been identified that would outweigh this harm.

For these reasons, the proposal would adversely affect the character and appearance of the PHECA. It would, therefore, conflict with Policy CS1(D) of the HCS, which concerns local character including harm to the significance of heritage assets, Policy DM1 of the DMP and with the Framework, in this regard.

Inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. Substantial 5 Paragraph 9.4.5 b) and g) weight should be given to any harm to the Green Belt and ‘very special circumstances’ will not exist unless the potential harm to the Green Belt by reasons of inappropriateness, and any other harm resulting from the proposal, is clearly outweighed by other considerations.

Reference is made to the accessible location and that two additional bicycle spaces would be provided. Given this is an extension to an existing dwelling I give these measures only very limited weight.

Reference is made to sustainable design and construction techniques and the proposal would provide some employment opportunities in the area with regard to the construction work and would be a more intensive use of the spacious site. However, construction jobs are likely to be limited in number and temporary, whilst there is no evidence the existing building cannot function satisfactorily as a dwelling at present. I therefore give these measures only very limited weight.

I have found that the proposal would adversely affect the character and appearance of the PHECA, and this carries weight against the proposal.

For these reasons I find that the other considerations in this case, as set out above, do not clearly outweigh the totality of the harm to the Green Belt that I have identified, and any other harm. Consequently, the very special circumstances necessary to justify the proposed development do not exist. The proposed development would therefore conflict with Policy G2 of the London Plan, and with Paragraph 149 c) of the Framework.

For the reasons given above, I conclude the appeal is dismissed.