Appeal 3276063

The appeal is dismissed.

The main issues are: i) 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; ii) the effect of the proposal on the openness of the Green Belt; iii) the effect of the proposal on the character and appearance of the area, with particular regard to the [site address] Estate Conservation Area (CA) and the Harrow Weald Ridge Area of Special Character (ASC); and iv) if the proposal would constitute inappropriate development, whether the harm by reason of inappropriateness and any other harm is clearly outweighed by other considerations so as to amount to the very special circumstances necessary to allow the appeal.

The appeal site is located within the Metropolitan Green Belt. Paragraphs 147 and 148 of the Framework advise that substantial weight should be given to any harm to the Green Belt and that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. Paragraph 149 of the Framework advises that the construction of new buildings should be regarded as inappropriate in the Green Belt, but exceptions 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 building’.

Policy G2 of the London Plan (2021) (LP) reflects the advice set out in the Framework with regard to development in the Green Belt. Policy CS 1 of the [name] (2012) (CS) states the quantity and quality of the Green Belt shall not be eroded by insensitive development, amongst other things. Policy DM 16 of the Harrow Development Management Policies (2013) (DMP) refers specifically to redevelopment and infilling of previously developed sites in the Green Belt. It offers support for development which would not have a greater impact on the openness of the Green Belt and the purposes of including land within it than the existing development with regard to a number of factors.

The appeal dwelling benefits from a single storey rear projection which provides annex accommodation. The council has suggested this does not form part of the original building on account of its different external materials and fenestration in comparison to the rest of the dwelling. The appellant has claimed the footprint of that extension pre-dates 1948. No evidence has been presented to support this claim and the appellant’s submissions in this regard lack clarity as to whether the whole of the single storey rear projection was erected pre-1948. On the information available, I am unconvinced that the annex extension was erected pre-1948 and forms part of the original building.

The appellant has not disputed the council’s calculations of the existing floor area of the appeal building, which amount to 206 sqm. This is 14 sqm larger than what the council claims to be the floor area of the original building. The appellant has clarified that the proposal would increase the gross internal area of the appeal dwelling to 302.3 sqm. In comparison to the existing floor area of the appeal dwelling, the appellant has claimed the proposal would comprise a 43% increase in floor area. This would be a significant increase in floor area.

The proposed development would comprise large extensions to the side and rear of the appeal dwelling. The proposed two storey rear extension in particular would dominate the original building on account of its width, depth, height and overall mass. Although the appeal dwelling is located within a substantial plot and the existing ridge height of the appeal dwelling would not be increased, the proposed extensions would comprise disproportionate additions over and above the size of the original building, as demonstrated by the significant increase in floor area.

The appellant has referred to local examples of extensions approved by the council at other locations and an appeal decision1 concerning a dwelling located within another local authority. In these instances, larger residential extensions than that proposed in this case were not considered to comprise disproportionate additions. I have seen the documents provided in those regards, and the judgment also referred to by the appellant2, but the findings of the council, Inspector, and the Court of Appeal in those cases do not lead me to conclude that the proposed development in this appeal would not result in disproportionate additions over and above the size of the original building.

The proposed development would not therefore accord with the exception provided at paragraph 149(c) of the Framework and it would constitute inappropriate development in the Green Belt, in conflict with Policy G2 of the LP and Policy CS 1 of the CS. 1 APP/Y3615/W/18/3202309 2 R (Heath & Hampstead Society) v [name] & Vlachos [2008] [name] 193

The appeal site is located on a private road made up of a mix of large dwellings. Some are of similar sizes to the appeal dwelling and some are much larger. All houses along the private road appear to be set within substantial plots, some of which are more secluded than others. Views of the proposed development from outside the appeal site would be limited on account of thick boundary planting and the set back position of the appeal dwelling within its substantial plot.

Paragraph 137 of the Framework states: ‘the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open; the essential characteristics of Green Belts are their openness and their permanence’. Paragraph 138 identifies five purposes Green Belts serve, including, amongst other things, to check the unrestricted sprawl of large built-up areas. Openness is therefore an essential characteristic of the Green Belt, which has spatial and visual aspects.

The proposed extensions would not increase the overall height of the existing building and would only slightly increase the proportion of the appeal site which would be developed, on account of the substantial size of the plot and relatively small existing and proposed building footprints. However, as set out above, the proposal would comprise disproportionate additions over and above the size of the original building. The significant increase in the size of the appeal building would be clearly appreciable from within the appeal site, but less so from outside the appeal site.

Taking all of the above into account, the proposal would harm the openness of the Green Belt spatially and visually by increasing the floor area of the appeal dwelling and its overall mass and built form. Considering the appeal site’s secluded location and the presence of larger neighbouring dwellings, the level of that harm would be low, but it would remain contrary to policy DM 16 of the DMP and the Framework.

The appeal building is a neatly proportioned detached dwelling with features reflective of the Arts and Crafts style within a substantial plot, which forms part of the CA and ASC. It appears as a large cottage with tall chimneys and rooms in the gambrel roof served by modest dormer windows to the front and rear. The council’s officer report raises no objection to the proposed 2 storey side extension and replacement garage in terms of their impact on the character and appearance of the area and I see no reason to disagree.

The CA Appraisal and [name] (2009) (CAAMS) describes the special interest of the CA as being derived from the low density development of detached houses within large plots, with semi-rural, secluded and tranquil qualities created by its private roads and dense greenery. The CAAMS also refers to the high architectural quality of properties which include a mix of Arts and Crafts, [name] and [name] inspired designs. These descriptions correspond with what I saw along [site address] , which define the significance of the CA and cover the positive attributes of this part of the ASC. As an attractive cottage with design features which reflect the Arts and Crafts style, set within a spacious, heavily planted plot, the appeal dwelling makes a positive contribution to the character and appearance of the CA.

The proposed 2 storey rear extension would comprise three gable ends, with the ridge of the central gable lowered below the existing roof ridge. The central gable would also be recessed to create a paved balcony at first floor level, while the two end gables would have Juliet balconies. It would occupy almost the full width of the existing building, being set in only slightly from each side. Its overall depth of 4.3 metres and width of 13.5 metres would be substantial in comparison to the relatively modest proportions of the existing building. It would dominate the rear elevation of the appeal dwelling and detract from the attractive cottage character and design features of the building.

Parts of the proposed 2 storey rear extension would be seen in limited views from [site address] and the rear gardens of neighbouring properties. All of those views would be restricted on account of their angles and intervening thick boundary planting, and they would be seen alongside similarly restricted views of the larger neighbouring houses immediately north and south of the appeal site. From what I saw, those neighbouring properties do not share the same architectural features and aesthetic qualities of the appeal dwelling.

Although only parts of the proposed rear extension would be visible in restricted views from outside the appeal site, in all views, including the private views from within the rear garden of the appeal site, the proposal would significantly change the character and appearance of the appeal dwelling. This would be on account of the scale and mass of the proposed rear extension and its introduction of paved and Juliet balconies, which would fail to respect the architectural qualities and proportions of the Arts and Crafts cottage style building within the [site address] Estate, such as its gambrel roof form with modest dormers. As a whole, the proposal would harm the significance of the CA.

The level of harm to the significance of the CA would be ‘less than substantial’ as referred to in the Framework. Paragraph 200 of the Framework advises that any harm to the significance of a designated heritage asset should require clear and convincing justification. Paragraph 202 sets out that where development would lead to less than substantial harm to the significance of a designated heritage asset, that harm should be weighed against the public benefits.

I am not aware of any public benefits associated with the proposal which would outweigh the harm identified. There would be a private benefit to the appellant and their family through the increased and improved living space, but this would not provide the clear and convincing justification needed to allow harm to the significance of the CA.

The proposal would therefore fail to preserve or enhance the character or appearance of the CA and would conflict with Policies D3 and HC1 of the LP, [name] 1 and CS 6 of the CS, [name] 1, DM 6 and DM 7 of the DMP, and the advice set out in the CAAMS. These seek to resist development which would be detrimental to local character and appearance and require, amongst other things, development to achieve a high standard of design which conserves and enhances the significance of heritage assets and architectural features that contribute towards local character. Policy CS 6 specifically requires development within [site address] to maintain its special character as part of the ASC, which is complemented by the advice of the CAAMS. The CAAMS seeks to maintain the CA’s townscape and built character, advising against development which does not complement the bulk, design and scale of existing buildings.

I have been referred to extensions to other properties approved by the council or other Inspectors, including at a site outside the Borough. Based on the information provided I am unconvinced that the same circumstances apply to the appeal proposal, where the architectural qualities of the appeal building would be harmed, to the detriment of the significance of the CA.

The appellant has referred to their need for additional floorspace to meet the needs of their family and has suggested that an alternative option to meet those needs would be through the erection of three single storey rear extensions and an outbuilding under the provisions of [name] and E of Schedule 2, Part 1 of the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended). I have been provided with a plan which shows the outline of those proposed extensions3, which it is claimed would form a realistic fallback option and result in a much larger increase in built footprint within the appeal site compared to the appeal proposal.

Detailed floor and elevation plans have not been submitted to show the proposed extensions and outbuilding claimed to comprise ‘permitted development’ would meet the appellant’s needs. Reference has been made to an Article 4 direction which the appellant claims would not affect the lawfulness of those works, but I have not been provided with a copy of that document. Taking the above into account, and in the absence of a Lawful Development Certificate confirming such works would not require planning permission, I am reluctant to conclude there is a greater than theoretical possibility they would be carried out. I am not convinced they would constitute a genuine and realistic fallback option and I therefore assign little weight to suggestions that the single storey extensions and outbuilding described by the appellant may cause greater harm to the openness of the Green Belt or character and appearance of the area.

I have seen letters of support from neighbouring residents which refer to the proposal as in keeping with the character of surrounding properties and the improved family living space which would be provided. I have found the proposal would harm the character and appearance of the area and fail to preserve or enhance the character or appearance of the CA, but I note the improved family living space which would be provided.

The benefits of the proposal, including improved family living space, would be modest and would not comprise the very special circumstances necessary to outweigh the substantial weight which the Framework advises I should assign to the harm which would be caused to the Green Belt, and the other harm identified which attracts less, but still significant weight.

The proposal would constitute inappropriate development in the Green Belt and would harm the openness of the Green Belt and the character and appearance of the area. It would conflict with the development plan taken as a whole and 3 The appellant’s Appendix 5 there are no material considerations that indicate my decision should be made other than in accordance with the development plan. Therefore, for the reasons given, I conclude that the appeal should not succeed.