Appeal 3370917

The appeal is allowed and planning permission is granted for the construction of a single storey rear extension, first floor extension and side facing porch following demolition of the existing porch at [site address] in accordance with the terms of the application, Ref 2025/0307/FUL, subject to the following conditions:

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

The development hereby permitted shall be carried out in accordance with drawing no: • 0247_02_001 – Site Location Plan • 0247_02_002 – Site Plans • 0247_03_001 – [name] • 0247_03_002 – [name] • 0247_05_001 – Southwest and [name] • 0247_05_002 – Northeast and [name]

The external materials of the extension hereby permitted shall match those used in the existing dwelling, unless otherwise stated on the approved plans.

The main issues are: • whether the proposal would be inappropriate development in the Green Belt having regard to the National Planning Policy Framework and any relevant development plan policies and the effect of the proposed development on the openness of the Green Belt; 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 it.

The appeal site [site address] comprises a two-storey detached dwelling, which abuts [site address] . The existing property sits on much lower ground that [site address] . The existing dwelling is finished in a white roughcast render with black fascias and grey concrete tile roof and white framed double uPVC glazed windows.

The proposed development would involve the erection of a single storey extension to provide additional living accommodation, a first-floor extension to provide a bedroom and a replacement porch to the side of the dwelling. The materials of the proposed extension would match those used on the existing property.

The appeal site is located within the Green Belt. Policy GN1 of the West Lancashire Local Plan 2012-2027 Development Plan Document, adopted 2013 (the Local Plan) advises that development proposals within the Green Belt will be assessed against national policies.

The National Planning Policy Framework (the Framework) identifies that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. It goes on to state that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances.

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 as set out in Paragraph 154 of the Framework. One such exemption being Paragraph 154(c) which relates 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.

The Framework does not provide a definition of a disproportionate addition. However, Policy GB4 of the Council’s Development in the Green Belt Supplementary Planning Document, October 2015 (the SPD) provides guidance for extensions of a building within the Green Belt. It states extensions should satisfy the specified criteria which includes that the total volume of the proposal, together with any previous extensions, should not result in an increase of more than 40% above the volume of the original building. However, the SPD also states that the figure of 40% is a guide only and every case will be assessed on its own merits.

Annex 2 of the Framework defines the “original building” as the structure as it stood on 1 July 1948, or, if built after that date, as originally constructed. In this case, the original building is believed to date from around 1690 and was restored in 1989. The appellant estimates that the original building has a volume of approximately 342.24m3, with later extensions adding a further 59.04m3.

The main parties agree that the cumulative increase in volume of the existing and proposed extensions, would be approximately 47%, which exceeds the 40% guideline set out in the Council’s SPD. However, proportionality is not determined solely by reference to a numerical threshold. The Framework makes clear that judgment must also take account of the scale, bulk, massing and height of the proposal, alongside the essential characteristics of the Green Belt and the five purposes. It is relevant to consider the proposal’s effect on these in reaching an overall view on whether it would amount to a disproportionate addition.

In this case, the proposed extensions would be located primarily to the rear of the host property, which is set below road level. This siting significantly reduces visibility from public vantage points. The largest increase in volume would arise from the first-floor extension, which would infill above the existing ground-floor footprint without projecting beyond the existing roof slope. Consequently, it would not be visible from the road-facing elevation and would remain in keeping with the two-storey form of the original dwelling. While the extension adds height and volume to the single-storey element, it does not enlarge the footprint or disrupt the dwelling’s proportions. The single-storey rear extension and replacement porch would also represent modest additions in terms of floorspace and volume.

Accordingly, although the cumulative volume exceeds the SPD guideline, I find that the extensions, taken together, would not appear disproportionate. Their limited scale and bulk, combined with the property’s sunken position, would result in only a minimal effect on the openness of the Green Belt in both spatial and visual terms. The proposal would not harm the essential characteristics or purposes of the Green Belt. On this basis, I conclude that the proposed development would not appear disproportionate in size.

I have had regard to a recent appeal decision1 at [address], Lathom in which the Inspector concluded that a volume increase of 46% would represent a notable, not marginal increase above the 40% increase within the guidance. However, I do not have full details of this proposal before me. Nevertheless, for the reasons set out above, I have found that the proposed development would not represent a disproportionate addition to the original building.

For these reasons, I therefore conclude that the proposal would not amount to inappropriate development in the Green Belt, and no conflict therefore arises with Policy GN1 of the Local Plan. It would also not be regarded as harmful either to the openness of the Green Belt or to the purposes of including land within it.

Given my conclusion on the first main issue, there is no requirement to assess if there are other considerations that amount to very special circumstances so as to justify the development.

I have imposed the standard time condition, a condition requiring development to be carried out in accordance with the approved plans, to provide certainty and a condition to ensure that external finishing materials of the extensions match those of the existing dwelling in the interests of the character and appearance of the host dwelling and the immediate area. 1 Appeal Ref: APP/P2365/D/24/3352640

The Council have suggested a condition to restrict permitted development rights under the Town and Country Planning (General Permitted Development) Order. However, these rights have not been withdrawn in the Green Belt. The Planning Practice Guidance advises such restrictions may fail tests of reasonableness or necessity, and no substantive evidence has been provided to justify the imposition of such a condition. Therefore, I have not imposed this condition.

For the above reasons, I have found above that the proposal would not be inappropriate development in the Green Belt, nor would there be material harm in any other respect. Consequently, there is no conflict with the development plan or the Framework and so the appeal should be allowed.