Construction of a single-storey rear orangery type conservatory and glazed link to utility room

Appeal Decision Site visit made on 10 October 2017 by John D Allan BA(Hons) BTP MRTPI an Inspector appointed by the Secretary of State for Communities and Local Government Decision date: 23 October 2017 Appeal Ref: APP/P1940/D/17/3179039 High Holly, Halifax Road, Heronsgate, WD3 5DF  The appeal is made under section 78 of the Town and Country Planning Act 1990 against a refusal to grant planning permission.  The appeal is made by Ms A Mawhood against the decision of Three Rivers District Council.  The application Ref 17/0664/FUL, dated 30 March 2017, was refused by notice dated 24 May 2017.  The development proposed is the construction of a single-storey rear orangery type conservatory and glazed link to utility room. Decision 1. The appeal is dismissed. Main Issues 2. 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 of the Green Belt and the character and appearance of the area, including the Heronsgate Conservation Area; and  If it 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 the development. Reasons Whether the proposal would be inappropriate development in the Green Belt 3. The appeal site lies within the Green Belt. The Framework explicitly states that inappropriate development is, by definition, harmful to the Green Belt. However, the extension of an existing building is not inappropriate provided that it does not result in disproportionate additions over and above the size of Appeal Decision APP/P1940/D/17/3179039 2 the original building. Policy CP11 Green Belt of the Council’s Core Strategy, adopted in October 2011, is consistent with the approach of national policy in that it states that there will be a general presumption against inappropriate development that would not preserve the openness of the Green Belt, or which would conflict with the purpose of including land within it. Part (b) to Policy DM2 Green Belt of the Council’s Development Management Policies Local Development Document (DMPLDD), adopted in July 2013, deals specifically with extensions to buildings and, consistent with national policy, states that extensions that are disproportionate in size to the original building will not be permitted. 4. The appeal property has previously been extended. According to the Council’s officer’s report, when taken with the previous additions, the proposals would result in an increase to the size of the original dwelling’s floorspace by around 149%. This figure has not been disputed by the appellant and exceeds by some considerable margin the Council’s normal guideline of 40% that is given within their 'Extensions to Dwellings in the Green Belt’ Supplementary Planning Guidance (SPG). This is referenced within paragraph 4.5 of the DMPLDD as relevant to the consideration of householder developments in the Green Belt and advises that extensions resulting in a cumulative increase of up to 40% compared with the original dwelling may not be disproportionate. 5. The appellant has drawn my attention to advice within the SPG that states, amongst other things, that ground floor conservatories of modest size compared to the house and site, would be taken as an exception to the normal 40% limit. There is no definition of ‘modest’ but in this instance the extension, which would have brick built walls atypical of a traditional conservatory albeit with a mostly glazed roof, would extend some 6m beyond the main rear wall of the original house. This would be well beyond the depth of an existing two- storey rear projection and would span a sizeable proportion of the building’s current width. In my opinion, rather than modest in size, it would amount to a fairly substantial extension and one that would little resemble a conservatory in terms of its appearance. I am therefore not persuaded that the proposal would satisfy the exception rule given within the SPG. 6. Overall, the combined forms of the proposed rear extension and glazed link would noticeably alter and enlarge the form and proportions of the original dwelling. There would be a fairly substantial increase to the scale and spread of built form on the site, regardless of the plot’s overall size. When this is considered along with the percentage increase in floorspace, I find that the proposal would be a disproportionate addition over and above the size of the original building. It would therefore amount to inappropriate development in the Green Belt for the purpose of the Framework and development plan policy. By definition this is harmful to the Green Belt and I attach substantial weight to this harm. The effect of the proposal on the openness of the Green Belt and the character and appearance of the area 7. The Framework states that an essential characteristic of Green Belts is their openness and that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land within them permanently open. The proposal would Appeal Decision APP/P1940/D/17/3179039 3 lead to an encroachment of built form into land that is currently open, particularly to the rear. As such, there would be some loss of openness to the Green Belt. This must be regarded as some additional harm to add to the harms by reason of inappropriateness and the conflict with development plan policy. 8. I note that the Council has no objection to the wider visual impact of the proposal. Given that the majority of the proposed works would be to the rear of the property and largely screened from any public vantage point, and that the link to the side would be glazed and lightweight in its appearance, I do not disagree. There would therefore be no harm to the character or appearance of the existing building or to the conservation area, the significance of which as a heritage asset would be unaffected. Nevertheless, the lack of any material harm in this regard is a neutral effect and does not attract any significant amount of weight in the scheme’s favour. Whether the harm by reason of inappropriateness, and any other harm, is clearly outweighed by other considerations 9. I have found the proposal to be inappropriate development for the reasons identified. This amounts to very substantial weight against it. In addition, I have also found that it would prejudice the openness of the Green Belt, albeit if only to a minimal degree. The appellant has drawn my attention to other properties in the area that have been extended by more than the 40% guideline. Whilst that may be the case, I have no specific details of any of the examples that have been listed. Regardless, the appeal falls to be considered on its own merits and, in any event, the original form of High Holly has already been enlarged well beyond the 40% guideline. Overall, I find that the other considerations that have been put to me are of insufficient weight to clearly outweigh the harms that I have identified. The very special circumstances necessary to justify the development do not exist. 10.I note suggestions that the appellant would consider demolishing an existing conservatory to one side of the dwelling and a garage. However, this does not form part of the proposal that is before me and does not alter my conclusion overall that the appeal should be dismissed. John D Allan INSPECTOR