Appeal 3354975

The appeal is dismissed.

The Government published a revised National Planning Policy Framework (the Framework) on 12 December 2024. Those parts of the Framework most relevant to this appeal have not been amended. As a result, I have not sought submissions on the revised Framework, and I am satisfied that no party’s interests have been prejudiced by taking this approach.

The main issues are: • Whether the proposal is inappropriate development for the purposes of the National Planning Policy Framework (the Framework) and the development plan policy; • The effect of the proposed development on the openness of the Green Belt; • The effect of the proposed development on the character and appearance of the dwelling and the area; and • If the proposal is 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 justify the development.

Development within the Green Belt is considered to be inappropriate unless one of the exemptions within the Framework applies. In this case the proposals need to be considered under Paragraph 154 part c) which allows for 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 LP34 of the Bracknell Forest Local Plan 2020-2037 (BLP) states that development in the Green Belt should be determined in accordance with national policy. The background text to the policy gives guidance that extensions which either individually or cumulatively increase the volume of an ‘original’ building by more than 40% is very likely to be regarded as disproportionate. Whilst it is recognised that the supporting text is not policy itself it provides a useful measure. Although the appellant has referred to existing development and the quality of the Green Belt in the surrounding area of the appeal site, the exception set out in Paragraph 154 c) focuses on the original building subject to the proposed extension or alteration.

The Council has calculated the original volume of [site address] to be 264.81m3 and, with previous extensions, the current building has a volume of 400m3, representing a significant 51.1% increase from its original form. The proposed extensions have been calculated to represent an 88.4% uplift in volume and a 96.6% uplift in floor area. Due to the significant increase in both volume and footprint of the proposed extension when compared to the original dwelling, the proposal would clearly result in disproportionate additions to the building.

On this basis, the proposal would be inappropriate development in the Green Belt.

Openness is identified in the Framework as one of the Green Belt’s essential characteristics. It has both spatial and visual aspects. The increase in floor area would enlarge the building’s footprint. This, and the additional bulk and volume of the proposed extensions, would have a material impact on openness, in a spatial aspect. In visual terms, although the house is situated within a large plot the extensions would be visible from the A road in front of the site and other nearby properties.

For these reasons, the proposed development would result in an adverse impact on both the spatial and visual openness of the Green Belt resulting in limited harm to the Green Belt.

No 1 forms part of a semi-detached pair. Both properties have previously been extended although in different ways. The neighbouring property has a two storey and single storey side extension. The appeal property has a side and rear extension. The side projection is small with an inset dormer window at first floor level on the front elevation and two similar dormers on the rear.

There is a new build development to the west which has dormer style projections at first floor level. The house to the east, The Nook, also has dormers visible on the front elevation. Dormer windows are not therefore uncharacteristic of the property or of the area.

However, existing examples are small scale and proportionate to the properties on which they are sited. The dormer proposed on the front elevation would expand across nearly the entirety of the roof on which it would be situated. It would appear crude, overly bulky, and top heavy, even read in combination with the other additions that have already taken place across the pair of houses.

The dormer windows on the rear of the proposed extension would be less visible from the road. There are some similarities in the approach to these windows and the existing rear dormers, however, their increased number, width and increase in the solid to void ratio would result in a poor design. Furthermore, the dormers would not be subservient to the roof and would appear at odds with the design of the house and its neighbour.

Green Belt matters aside, the scale of the extension does to some degree balance out the property with its neighbour. However, the form of the dormers, particularly the one on the front would have a significant and perceptible harmful impact on the property in terms of design.

The proposed extension would harm the character and appearance of the area and would therefore be contrary to Policy LP50 of the BLP which, amongst other things, supports developments which relate well to their location and surroundings through their siting and scale, form, roofscape, design and materials.

Details of an alternative proposal have been provided. A Lawful Development Certificate (ref 24/00400/CLPD) confirmed that a single storey side extension, single storey rear extension and new wrap around side and rear dormer could be constructed under permitted development. The plans show improvement works adding bedroom space and increasing ground floor accommodation which may achieve similar aims to the appeal scheme. There is a more than theoretical possibility of the certified development being carried out and it therefore represents a realistic fallback option.

However, the appeal proposal would be 12% larger than the certified development. Whilst this may not be a large percentage, it is on top of a 75.6% uplift and therefore would be an even more disproportionate addition to the original house.

The appeal proposal would also extend the property further to the side at first floor level which would have a much greater impact on the openness of the Green Belt, particularly the spatial aspect. Although the inclusion of the dormer within the fallback scheme would add an additional storey, it would read as an addition to the existing roof and would be contained within the footprint of the existing house. This means that the fallback scheme’s additional impact upon the spatial and visual aspects of the Green Belt’s openness would be limited.

Overall, the proposed side extension would have a significantly greater impact on openness than the permitted development scheme. It follows that the fallback position is a less harmful alternative and therefore carries little weight as a consideration in the scheme’s favour in this respect.

It is also contended that the proposal would be a more appropriate design than the fallback scheme. However, I am more of the view that both schemes represent unattractive, poor design, albeit in different ways. This consideration is therefore not a compelling one in favour of the appeal scheme.

The proposal may provide needed family accommodation, however, as the fallback position demonstrates there are alternative routes to meeting this aim.

Reference is made to an approval at The Nook (ref:17/01280/F) the appellant states that the property had already been extended by 153.2% and that permitted development was given substantial weight when allowing further additions. The specific details of this case, including the scale of the permitted development fallback position, have not been provided to demonstrate that the cases are sufficiently comparable.

The development at [name] (ref:18/00348) is not comparable as it relates to a redevelopment site for new housing rather than the extension of a single dwelling, and so would have been assessed under a different policy context.

The approval by committee the development to the rear of Oak Tree Nursery (ref: 22/00613/FUL) is referenced, but as with the above this does not relate to a house extension proposal.

Whilst there are a number of recent approvals on [site address] , I do not find that permissions provided are sufficiently similar. Likewise, given that the original scheme for the site does not form part of any development proposal, extant or otherwise, it is a consideration of very limited weight.

The proposed extensions to the building would constitute inappropriate development in the Green Belt resulting in limited harm to its openness. Inappropriate development is by definition harmful to the Green Belt. In accordance with the Framework, I give substantial weight to the harm to the Green Belt and its openness.

The other considerations in this case do not clearly outweigh the harm arising from the appeal scheme that I have identified. Consequently, the very special circumstances necessary to justify the development do not exist. It follows that the proposal would conflict with Policy LP34 of the BLP which seeks to ensure that the Green Belt is preserved from inappropriate development in line with national policy.

The proposal conflicts with the development plan and the material considerations do not indicate that the appeal should be decided other than in accordance with it. For the reasons given above the appeal should be dismissed.