Appeal 3312590

The appeal is allowed and planning permission is granted for first floor front extension at [site address] in accordance with the terms of the application, Ref 22/02057/FUL, dated 4 October 2022, subject to the following conditions:

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the following approved plans: Location Plan (01)14, [name] (01)11, [name] and [name] (01)10, Block Plan (01)15, [name] (01)13 and [name] and [name] (01)12.

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 main issue is whether or not the appeal scheme is inappropriate development in the Green Belt having regard to the National Planning Policy Framework (the Framework) and any relevant development plan policies.

The appeal site is a semi-detached dwelling located within the Green Belt. The Framework in Paragraph 137 identifies that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. The Framework further establishes that the construction of new buildings in the Green Belt should be regarded as inappropriate, subject to a number of exceptions. One such exception of relevance to this case is at Paragraph 149 c), with regard to 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.

In relation to existing uses within the Green Belt, Policy D23 of the Local Development Framework Development Policies (2009) (LDF) sets out that extensions and/or alterations to existing dwellings may be appropriate where, amongst other things, the extensions are not disproportionate over and above the size of the existing building(s) when originally constructed. In this respect, the policy is broadly consistent with the Framework.

The Framework does not provide a definition of ‘disproportionate additions’ and therefore an assessment of whether a proposal would amount to a disproportionate addition over and above the size of the original building is a matter of planning judgement. The Residential Design Guide Supplementary Planning Document (2018) (SPD) advises that a maximum extension of up to 50% of the volume and 50% of the floor space of the original house may be regarded as proportionate over and above the size of the original house.

The proposal comprises a first-floor infill extension and the original house has previously been extended. There is dispute over the volume of the original dwelling, with the appellant suggesting 340m3 and the Council suggesting 205m3. The Council has not shown how it arrived at the figure, but the appellant has provided detailed calculations and a methodology. Given the accepted footprint of the original dwelling, for the Council's calculation to be correct, the floor to ceiling height would have to be only a little over 2m, which seems unlikely, and with little to no volume in the roof. Moreover, previous ground floor projections would have to be ignored.

The Council's figure, therefore, seems unrealistic and the appellants much more likely. On this basis, the proposal would be within the 50% threshold set out in the SPD.

Even if I am wrong, neither Policy D23 nor the SPD suggest that the 50% guideline should be an absolute maximum. The proposal would extend the house to the side in a very similar manner to that at the adjoining neighbour. The resultant balancing effect would mean that the proposal did not appear to be a disproportionate extension viewed in the context of the building as a whole.

As such, I find that the proposal would comply with the exception set out in Policy D23 and the Framework and so would not be inappropriate development in the Green Belt. It follows that the proposal would not be harmful to the openness of the Green Belt or to the purposes of including land within it. A case for very special circumstances is not therefore required.

In addition to the standard time limit condition, it is necessary to ensure that the development is carried out in accordance with the approved plans to provide clarity. A condition requiring external materials to match the existing building is reasonable and necessary to protect the character and appearance of the area.

For the reasons given, having taken account of the development plan as a whole, the approach in the Framework, along with all other relevant material considerations, I conclude that the appeal is allowed.