Appeal 3339843

The appeal is dismissed.

The site visit was undertaken by a representative of the Inspector whose recommendation is set out below and to which the Inspector has had regard before deciding the appeal.

I have omitted wording regarding a proposed pergola from the description of development on the application form, as the pergola was removed from the proposal during the course of the application.

Prior to the determination of this appeal, a revised version of the National Planning Policy Framework (the Framework) was published in December 2024. The changes therein, as far as they relate to the substantive matters of the appeal, have not however changed fundamentally. I am satisfied that neither main party or their respective cases would be prejudiced by taking account of the revised Framework or proceeding without further consultation.

The main issues are a) whether the proposal would be inappropriate development in the Green Belt; b) it’s effect on the openness of the Green Belt; and c) if it would be 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 Framework establishes that development in the Green Belt is inappropriate unless a specified exception applies. These are listed in paragraphs 154 and

Paragraph 154 c) of the Framework 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 GB1 of the [name] and Allocations Local Plan (2022) (DALP) is consistent with the Framework in these regards.

The Framework does not define ‘disproportionate’. However, Policy GB1 states that the increase in the size of a building by up to 30% of the original building volume is considered an acceptable increase for proposals for replacement, extension and alteration.

The Framework defines ‘original building’ as ‘a building as it existed on 1 July 1948, or, if constructed after 1 July 1948, as it was built originally.’ The appeal property is shown on a map from 1844. The Council has made an estimation of the extent of the original dwelling based on drawings from a previous planning application. The Council goes on to calculate that earlier extensions have increased the footprint of the dwelling by 73%, and that the appeal proposal would result in an overall increase of approximately 80%. The appellant does not dispute these figures.

The 30% threshold set out in Policy GB1 refers to the volume of a building, whereas the Council’s calculations are based on the building’s footprint. The increase in volume is therefore unknown. The appellant however accepts that historic development has exceeded the arithmetic threshold. Nevertheless, size can be more than a function of volume and footprint. In this case, the scale, bulk and mass of the building has already been considerably increased through the previous extensions. The appeal scheme would further noticeably increase the massing and scale of the dwelling.

My attention has been drawn to a previous appeal decision at [address], Studham1, where an extension to a dwelling was allowed which exceeded a 60% threshold set out in the [name]. However, this threshold was set in a guidance document, while the 30% threshold in this case is part of an adopted policy. Moreover, in the Studham appeal it was considered that the altered building ‘would not be perceived as one that has been extended disproportionately’. This is not the case in the current appeal, given the depth of the existing rear extensions at the appeal property together with the reasons set out above. As such, the Studham appeal does not justify

I have also been referred to an appeal at [address], Seale2, which allowed a two-storey rear extension to a dwelling in the Green Belt. However, in this case the development plan policies did not identify specific limits or thresholds in terms of floorspace or volume. Furthermore, the two-storey extension was to be situated between two existing rear projections and thus did not extend the built form of the dwelling beyond the envelope of the existing development. In the current appeal, the footprint of the proposed 1 Planning appeal ref. APP/P0240/D/16/3148359 2 Planning appeal ref. APP/Y3615/W/18/3202309 2 extension would be larger than that of the existing conservatory by a not insignificant amount. The Seale appeal is therefore not directly comparable to the scheme before me.

I understand that planning permission was granted on 16 February 20223 for an extension at [address], [site address] . However, the DALP was adopted on 2 March 2022, after the application was determined. I have no information before me about the development plan policy context, including whether there were any limitations or thresholds to extensions to properties in the Green Belt, that was in place at the time of the application at [address]. Furthermore, the officer’s report has not been provided so I am unable to make any meaningful comparison between the reasons for granting permission at [address] and for refusing the application at the appeal site. I am therefore not persuaded that the extension at [address] is directly comparable to the

Planning permission has recently been granted for an extension4 to 1 [address], Daresbury. Whilst full drawings of the extension have not been provided, I note that the extension would be at the first-floor level and is therefore unlikely to increase the size of the footprint of the building, unlike the scheme before me. Furthermore, the applicant has calculated that the extension at No 1 would increase the volume of the original building by 36%. Although the increase in volume at the appeal property is not known, the scheme at No 1 would represent a much smaller increase in the size of the original building than the appeal scheme. As such the planning permission at No 1 is not directly comparable to, and does not justify, the appeal proposal.

Subsequently, and taking all of the above into account, the appeal scheme may fairly be described as ‘disproportionate’ within the terms of the Framework and Policy GB1 of the DALP. The proposal would therefore be inappropriate development which is, by definition, harmful to the Green Belt. This would result in conflict with both the Framework and DALP Policy GB1.

Openness is an essential characteristic of the Green Belt. The Planning Practice Guidance explains that openness can have spatial and visual aspects. The land take and mass of the proposed extension would take up otherwise undeveloped space in the Green Belt. As such, there would be an unavoidable reducing effect on the spatial aspect of its openness. There would be a more limited effect on the visual aspect given the built-up nature of the immediate area. Nonetheless, one of the fundamental aims of Green Belt policy is to keep land permanently open and, having regard to the Framework, any reduction to the Green Belt’s openness would be harmful. This would be in addition to that caused by the inappropriateness of the development.

The appeal site lies within the Daresbury Conservation Area (CA). The significance of the CA derives from its historical buildings and architectural details along with the linear pattern of development. The proposed extension would replace an existing conservatory which is in a poor condition, and it would be to the rear of the property with limited visibility from the street. The 3 Planning application ref. 22/000001/FUL 4 Planning application ref. 24/00375/FUL 3 proposal would therefore have a minimal effect on the street scene and thus would preserve the character and appearance of the CA. However, this would be a lack of harm and therefore would carry neutral weight.

The replacement of the conservatory would result in energy efficiency improvements; however, it has not been demonstrated that these could be achieved in a way that does not cause harm to the Green Belt. As such I attach limited weight to this matter.

The proposed extension would cause harm to the Green Belt by way of inappropriateness and through reducing openness, to which substantial weight should be afforded. Development should not be approved unless the harm to the Green Belt, and any other harm, is clearly outweighed by other considerations. Those considerations I have identified would not attract sufficient weight to clearly outweigh the totality of the harm. Consequently, the very special circumstances necessary to justify the proposed development do not exist.

There are thus no material considerations, including the approach of the Framework, worthy of sufficient weight, which indicate that a decision should be made other than in accordance with the development plan. I therefore recommend the appeal be dismissed.

I have considered all the submitted evidence and my representative’s report and on that basis the appeal is dismissed.