Appeal 6003536

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.

There is a discrepancy regarding the appellants surname as stated on the application form and the appeal form. During the appeal process, the appellant confirmed that the correct spelling of the surname is ‘Masani’, which has been used in the banner heading above.

The main issues are:  whether the proposal would be inappropriate development in the Green Belt having regard to the National Planning Policy Framework (the Framework) and any relevant development plan policies;  the effect of the proposal on the openness and purposes of the Green Belt;  the effect of the proposal on the long-term health and vitality of trees, bearing in mind that it would be within the Northaw Conservation Area (NCA); and  whether any harm by reason of inappropriateness, and any other harm, would be clearly outweighed by other considerations, so as to amount to the very special circumstances necessary to justify the development.

The appeal site lies within the Metropolitan Green Belt. The Framework states that the fundamental aim of the Green Belt policy is to prevent urban sprawl by keeping land permanently open.

Paragraph 154 of the Framework sets out that development in the Green Belt is inappropriate other than in the case of specified exceptions. An exception at paragraph 154c) is the extension or alteration of a building, providing that it does not result in disproportionate additions over and above the size of the original building. The proposal is physically separate from the main dwelling but functionally related to it and therefore falls within the scope of paragraph 154c). The main parties agree, and I find no reason to come to a different view. Policy SADM34 of the Welwyn Hatfield Borough Council Local Plan (2023) (LP) reflects the approach of the Framework, to the extent that it is relevant to this appeal.

The Framework does not define what a disproportionate addition is, therefore, it is a matter of planning judgement. It is well established that a comparison should be made between the building as originally built and the building as proposed to be extended, together with any existing extensions. Policy SADM34 is consistent with this approach and also requires regard to be given to the prevailing pattern of development and the established character of the surrounding area. The supporting text indicates that a quantitative and qualitive assessment should be undertaken and sets out that an addition being 50% greater than the original building would generally be considered to be disproportionate.

The Council indicate that the floorspace of the original building was approximately [address] metres (sqm) and that, through subsequent additions and extensions, it has increased to 171sqm. The proposal would increase it a further 26.95sqm. While this represents a modest addition when considered in isolation, the cumulative increase in built form at the site would amount to approximately 230%, far exceeding the 50% threshold. The appellant has not disputed the Council’s figures, nor have they provided any alternative calculations and contend that having regard to the characteristics of the site, the proposal would not amount to a disproportionate addition.

The above figures demonstrate that the original building has already undergone a substantial cumulative increase in floorspace, and the proposal would add further to this built form. Moreover, despite the generous plot size and the overall extent of the visual perception of the proposed structure, the proposal would include a large area of hardstanding and would result in further spreading out of built form within the site. When considered in combination with the footprint and external dimensions of the proposal and the scale of previous additions, the overall effect would be excessive. Consequently, the proposal would constitute a disproportionate addition over and above the size of the original building and would not comply with paragraph 154c) of the Framework or Policy SADM34 of the LP.

It has not been suggested that the proposal would meet any of the other listed exceptions at Framework paragraph 154, and there is nothing before me that would lead me to find otherwise. As such, the proposed development fails to meet any of the exceptions set out in Framework paragraph 154 and would therefore be inappropriate development, which is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances.

The Framework explains that the essential characteristics of Green Belts are their openness and their permanence. Openness has a spatial and visual aspect.

The proposal would be sited in the garden to the rear of the main dwelling, against the established vegetated boundary. It would introduce further built form, where none existed previously, therefore it would have a harmful effect in spatial terms on the openness of the Green Belt.

The proposal would generally be screened from wider public views and would therefore have a limited effect on the visual perception of openness. However, the fact that parts of the Green Belt are not readily visible does not in itself justify a reduction in openness since to do so would support a continual and cumulative loss. Overall, the proposal would result in moderate harm to openness. Having visited the site I see no clear reason to depart from the Council’s findings that the proposal would not conflict with the five purposes for including land in the Green Belt. The lack of harm on this matter would be a neutral factor, weighing neither for nor against the proposal.

The site is located within the NCA and in line with section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 (the Act) I have paid special attention to the desirability of preserving or enhancing the character or appearance of the conservation area. From my observations, the significance of the NCA, insofar as is relevant to this case, is primarily derived from its verdant character, created by buildings within a landscaped setting. Trees also form an important part of the character of the area. As a verdant plot of land accommodating a number of mature trees with amenity value through public views the appeal site makes a positive contribution to the NCA.

The proposed development would be proximate to mature trees that are prominent at the roadside edge of the site at western entrance to the village; however, no information has been provided to demonstrate that their long-term health and vitality would not be compromised through root disturbance, physical damage, or future pressure for tree works. In the absence of any assessment or any consideration of mitigation, I cannot be confident that the trees would be adequately protected. Given the prominence of the trees and the contribution they make to the landscape quality of the site and to the significance of the NCA, a precautionary approach is reasonable. As such, this is a matter that should be resolved before planning permission is granted rather than leaving it to a planning condition to ensure that any required mitigation could be satisfactorily achieved.

The potential loss of trees or decline arising from the proposal would harmfully diminish the verdant character of the site and the positive contribution it makes to the character and appearance of the area. As such the proposal would be contrary to the Framework which seeks the retention of existing trees due to the contribution they make to the character and quality of urban environments and to climate change mitigation.

Considering the nature and extent of the proposed development, it would fail to preserve or enhance the character or appearance of the NCA and would harm its significance as a whole. For the purposes of the Framework, the harm to the designated heritage asset would be less than substantial, and towards the lower end of the spectrum but nevertheless of considerable importance and weight. In these circumstances the Framework states that the harm should be weighed against any public benefits.

In the absence of any defined public benefit to outweigh the identified harm, the proposal would fail to meet the requirements of section 72(1) of the Act and the provisions of the Framework that seek to conserve and enhance the historic environment.

To conclude, the proposal would not protect the long-term health and vitality of protected trees, bearing in mind that it would be within the NCA. Accordingly, it would be in conflict with Policies SP9 and SADM16 of the LP which require development to conserve and enhance the character of an area and the natural and historic landscape.

I have found that the proposal would not protect important trees in the NCA in conflict with the development plan.

The proposal would be inappropriate development in the Green Belt. No harm would arise to the Green Belt purposes however there would be a moderate loss of openness which would be harmful to the Green Belt. The totality of the Green Belt harm attracts substantial weight. Very special circumstances will not exist unless the potential harm to the Green Belt by reason of inappropriateness, and any other harm resulting from the proposal, is clearly outweighed by other considerations. There are no other considerations to clearly outweigh the harm I have identified. Consequently, the very special circumstances necessary to justify the development do not exist and the proposal would fail to accord with the Green Belt aims set out in Policy SADM34 of the LP and the Framework.

For the reasons given, my above findings bring the proposal into conflict with the development plan, read as a whole. There are no material considerations, including the Framework to indicate a decision should be made otherwise than in accordance with it. Therefore, I recommend that the appeal should be dismissed.

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