Appeal 3269630

The appeal is allowed and planning permission is granted for the proposed two storey side extension at [site address] , [address], Copthorne, [postcode] in accordance with the terms of the application, [name]/2020/2009, dated 24 April 2020 and subject to the conditions listed below.

The development hereby permitted shall begin not later than three years from the date of this decision.

The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building.

The development hereby permitted shall be carried out in accordance with the following approved plans: S2020/LP1, S2020/01 Rev.A, S2020/02, S2020/03 Rev.B and S2020/04 Rev.B

On 20 July 2020 the Government published a revised version of the National Planning Policy Framework (July 2021) (revised Framework). However, the Green Belt policies that are relevant to this appeal have not changed and there was no need therefore to invite the parties to make further submissions in response to the revised Framework. The paragraph numbering for the Green Belt policies has changed and I have highlighted those changes in my decision.

The main issue is whether the proposal would be inappropriate development in the Green Belt having regard to the revised Framework and development plan policy.

The appeal site comprises an end of terrace two storey pitched roof dwelling with gardens to the front, side and rear. There are also various timber outbuildings within the extensive garden areas to the host property. Access to the appeal site is via a short track that leads to [address]. The appeal site forms part of a terrace of three properties. The surrounding area is rural in character, but includes similar ribbons of development as well as larger commercial buildings and uses, particularly to the south and south west of the appeal site.

The Council contend that the proposed extension would be disproportionate to the original building resulting in significant harm to the openness of the Green Belt. This harm arises, the Council argue, from the appeal proposal being mathematically and visually disproportionate to the modest scale of the original building, representing a significant addition to the bulk and size of the building. In relation to the mathematical assessment, the Council indicate that the appeal proposal would result in an increase of approximately 43.5% in the volume of the original building. In all other respects, the Council found that the appeal proposal would be acceptable and that specifically it would not harm the living conditions of neighbouring occupiers or impact on character and appearance.

The construction of new buildings within the Green Belt is inappropriate development unless it falls within one of the exceptions listed a) to g) (inclusive) in paragraph 149 of the Framework (previously paragraph 145). Exception c) states that the extension of an existing building is not inappropriate development provided “it does not result in disproportionate additions over and above the size of the original building”.

A similar approach is set out in Policy DP13 of the Tandridge Local Plan Part 2: [name] (July 2014) (TLP), in that it states that the extension of buildings within the Green Belt will only be allowed where the proposal does not result in a disproportionate addition over and above the size of the original building. As such and whilst Policy DP13 predates the revised Framework, I am satisfied that, insofar as it relates to extensions, this policy is consistent with the Framework.

The supporting text, in paragraph 13.2 of the TLP, further states that the original building is to be taken as the building that existed at 31 December 1968 (when the policy was first introduced) or if constructed after, as it was built originally. In this case, the parties are agreed that the original building excludes the single storey side extension (covered terrace). I have no reason to disagree with that approach and have, therefore, assessed the appeal proposal on that basis.

Paragraph 13.4 of the TLP states that, as a general rule, the Council will use the calculation of external volume as a measure of whether an extension is mathematically disproportionate. Even so, the supporting text does not expand on this further and neither does it indicate what percentage increase in volume might be regarded as being disproportionate in individual cases. This paragraph must be read in conjunction with paragraphs 13.3 – 13.4, which further state that the Council will adopt a pragmatic approach and judge each proposal on its individual merits. Also, that regard will be had to the size of the original dwelling in terms of its bulk, height and mass, the prominence of the extension and its impact on the openness of the Green Belt.

The overall approach set out in the TLP is similar to the analysis required by paragraph 149 c) of the revised Framework (previously paragraph 145 c)), namely whether the proposed extension is disproportionate to the “size” of the original building. The proposed increase in volume, external measurements and floorspace are all, therefore, relevant to that assessment, as is the appeal sites’ context and the prominence of the proposed extension.

Within the above context, the parties appear to agree that the appeal proposal would result in an increase in the volume of the original building of approximately 43.5%. In simple mathematical terms, I do not consider such an increase to be disproportionate. The Council have not provided any substantive evidence to support its finding as to why this increase would be mathematically disproportionate and as I confirmed above, the development plan does not provide any support or guidance as to what would generally or broadly be considered an acceptable increase in volume.

Based on the submitted plans, the width of the proposed extension would be under half the width of the original building. This is reaffirmed by the Appellants measurements, which indicate that the original building is 7.6 metres wide and the proposed extension 3.4 metres wide. The increase in floorspace would similarly be under half that of the original building. On the ground floor, the new extension would have a broadly similar footprint to the existing single storey extension (covered terrace), other than where there is a small projection at the front. On the first floor, the new extension would not project beyond the main front or rear walls of the original building. Neither would this part of the extension exceed the eaves and ridge height of the original building.

Based on all of these measurements and factors, the proposed extension would not, in my judgement, be disproportionate to the original building. That finding is the same whether it is based on a mathematical or visual assessment of the

[name] accept that the bulk, mass and volume of the original building would increase, compared to existing, that increase would not be significant or disproportionate. The proposed extension would assimilate well with the original building and appear as a logical extension to it, and would not dominate its appearance. With the new extension designed to reflect the detailing and materials used on the original building, the proposal would not be out of keeping when viewed in the context of the scale and form of the original building and would not be visually prominent.

In reaching the above findings and as paragraph 13.3 of the TLP states, I have adopted a pragmatic approach and judged the proposal on its individual merits.

Accordingly, the appeal proposal would not represent inappropriate development in that the proposed extension would not result in a disproportionate addition over and above the size of the original building. The appeal proposal would, therefore, be in accord with the exception set out in paragraph 149 c) of the revised Framework (previously paragraph 145 c)).

In relation to the Council’s concerns over the impact on or the loss of openness within the Green Belt, the proposed development would not be inappropriate and would not, therefore, be harmful to the openness of the Green Belt or to the purposes for including the land within it. The impact on openness is implicitly taken into account in the exceptions set out in paragraph 149 of the revised Framework (previously paragraph 145). In this particular case, the exception under part c) of paragraph 149 does not require consideration to be given to the actual effect of the new extension on openness in determining its inappropriateness. In view of this, the appeal proposal would also accord with Policy DP10 and DP13 of the TLP.

The Council has suggested a number of conditions which I have considered against the advice in the revised Framework and the Planning Practice Guidance on the use of planning conditions. Conditions relating to the time limit for implementing the development, compliance with the submitted plans and for materials to match existing, are necessary and reasonable in order to secure a high quality development and to reflect the details included within the application. However, I have added a list of approved plans for clarity.

For the reasons given above and having taken all the matters raised into account, I conclude that the appeal should be allowed.