Appeal 3295821

The appeal is allowed and planning permission is granted for demolition of the existing conservatory to the rear of the dwelling to be replaced with a single storey extension, at [site address] in accordance with the terms of the application, Ref 3/21/2833/HH, dated 10 November 2021, and 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: 202014-01 ([name]); 202014-01 ([name]); 202014-03 [name] ([name]); 202014-04 [name] ([name]); 202014-05 [name] (Location and [name]).

An application for an award of costs has been made by [name] against East Hertfordshire District Council. This is the subject of a separate decision.

The appellant has submitted revised drawings which clarify some minor uncertainty regarding the shape of the walls and roof of the proposed extension and include a previously omitted front porch. Having regard to the Wheatcroft1 principles, I am satisfied that these plans do not materially alter the proposal and no party would be prejudiced by my taking them into account in consideration of the appeal.

The site lies within the Metropolitan Green Belt. Therefore, the main issues are: [site address] Wheatcroft (Bernard) Ltd v Secretary of State for the Environment (1982) JLP 37 • Whether the proposal amounts to inappropriate development in the Green Belt; • The effect on the openness of the Green Belt and the purposes of including land within it; • If the development is inappropriate, whether any 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.

Paragraph 149 of the National Planning Policy Framework (the Framework) states that the construction of new buildings within the Green Belt is inappropriate development but lists certain forms of development which are not regarded as inappropriate. This includes 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 specific proposal in this case would be to replace an existing rear conservatory with a single storey rear lean-to extension. The proposed extension would match the overall height and depth of the existing, with an increase in floorspace of some 2.4sqm where a straight rear wall would replace a presently recessed doorway between two window bays, along with a small increase in volume to create a single, lean-to roof. The degree of change, in terms of floorspace, volume and overall shape, would thus be very limited.

The host dwelling has been extended in the past, notably through a two storey side extension and the existing conservatory. The Council argues that the various extensions have cumulatively enlarged the floorspace of the original building from some 84sqm to around 220sqm. This would rise to approximately 222.5sqm when the proposal is considered, an increase in the order of 164.8% over the original floorspace.

The Council appears to have included an outbuilding to the rear of the garden within its calculations, based on its distance from the main dwelling. The Council has not explained the basis for this approach, nor have I been provided with any policy or guidance which sets out criteria for when outbuildings should be included when assessing disproportionate additions within the Green Belt. I saw the outbuilding to be clearly detached at the rear of the garden and not close enough physically to read as part of the overall massing of the main dwelling. Consequently, I am not persuaded that it should be regarded as an extension of the main dwelling. I do not have a floorspace measurement for the outbuilding itself but omitting it would clearly reduce the percentage increase set out by the Council.

However, whilst the degree to which the footprint of the existing building would increase is modest, the Framework test requires comparison with the original building. Although ‘disproportionate’ is not defined within the Framework, nor in any development plan policy or other guidance put to me, I accept that the increase in size from past extensions, even when omitting the outbuilding, is still likely to be well over 100%, which is significant by any measure.

Therefore, I find that the proposal would result in disproportionate additions over and above the size of the original building. As such, the proposal would amount to inappropriate development in the Green Belt.

The fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open; the essential characteristics of Green Belts are their openness and their permanence. Openness in terms of the Green Belt has a spatial aspect as well as a visual aspect.

The Council accepts that, given the concealed location of the extension, it would have no effect on openness in visual terms. Spatially, the extension would involve a very modest increase in the footprint of the building, which would occur within the external dimensions of the existing conservatory. The change would be to a part of the building hidden from public view and where this limited change would be imperceptible, with no tangible effect on the overall spatial impact of the building within the Green Belt.

Therefore, I conclude that the proposal would not have a materially harmful effect on openness. Moreover, the proposal would not lead in any substantive way to encroachment of development into the countryside and would not impact on this or any other Green Belt purpose.

The appellant refers to other nearby developments where larger extensions or rebuilding schemes have been permitted. I do not have full particulars of these proposals, but I saw larger dwellings in close proximity to the appeal site, which lies within a village setting where residential development of varying scale exists, some larger than the proposal before me.

The original dwelling has become larger through past extensions, but its size and form is now well established. As the existing side extension replicates the height and form of the original dwelling, it does not appear as an extension, but has reimagined the overall form as a wider, two storey dwelling. As a result, and notwithstanding that the extensions may be disproportionate in Green Belt terms, the side extension does not overpower the original dwelling or diminish its character. The commensurate degree of extension to the other half of the semi-detached pair also retains an overall balance of form and scale. This being the case, the full-width extension to the rear would read as a modest, subservient addition to the established, wider form of the dwelling. Indeed, the Council did not oppose the design of the extension. Having regard to the proposed form and materials, and its concealed location to the rear, I am satisfied that it would preserve the character and appearance of the host dwelling and wider area.

Given the similarity in scale and position between the existing and proposed extensions, I am also satisfied that neighbours to the site would not see their living conditions adversely affected by the proposal. The proposal would also have no effect on existing parking or access arrangements.

The appellant also points to benefits in terms of the improved liveability of the conservatory space should the ‘pinch point’ of the existing patio door be removed and improved thermal and energy efficiency measures be incorporated, that would replace the increasing deterioration of the conservatory which is in ongoing need of remedial work. Such considerations would attract some modest weight in favour of the proposal.

Importantly, the existing scale of development at the appeal site has been achieved through past planning applications which found the extensions acceptable in planning terms. As such, any effects these extensions have had on the Green Belt or its purposes have already occurred and would not be repeated or exacerbated by the proposal. Consequently, I give significant weight to the fact that the vast majority of the extensions contributing to a finding of inappropriate development already exist and that the proposal, effectively a replacement structure, would not materially worsen the effects on the Green Belt.

The proposal would cause harm to the Green Belt by way of inappropriateness, to which I must afford substantial weight in accordance with the Framework, which adds that development should not be approved unless the harm to the Green Belt, and any other harm, is clearly outweighed by other considerations.

Taken together, I find that the negligible increase in scale proposed, the past acceptance by the Council of extensions of almost the same size, the absence of harm to Green Belt openness or the character of the area, and the modest but nevertheless positive improvements to thermal and energy efficiency within the building, clearly outweigh the totality of the harm identified to the Green Belt. Consequently, I conclude that the very special circumstances necessary to justify the proposal exist.

[name] have found above that very special circumstances exist to justify development in the Green Belt, the proposal would accord with national policy set out in the Framework and Policy GBR1 of the East Herts District Plan 2018, which sets out that planning applications within the Green Belt will be considered in line with the provisions of the Framework. There are no material considerations which indicate that a decision should be made other than in accordance with the development plan.

Therefore, the appeal should be allowed, subject to a condition requiring development to be carried out in accordance with the approved plans, to provide certainty. A condition requiring materials to match the existing building is not necessary as the proposed materials are set out on the plans.