Construction of single storey side extension at existing detached dwelling house

Appeal Decision Site visit made on 13 August 2019 by Sarah Manchester BSc MSc PhD MIEnvSc an Inspector appointed by the Secretary of State Decision date: 14th November 2019 Appeal Ref: APP/N5090/D/19/3230079 82 Galley Lane, Barnet EN5 4AL • 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 Mr & Mrs Gerard against the decision of the Council of the London Borough of Barnet. • The application Ref 19/1835/HSE, dated 27 March 2019, was refused by notice dated 23 May 2019. • The development proposed is construction of single storey side extension at existing detached dwelling house. Decision 1. The appeal is dismissed. Main Issues 2. The main issues are: i) Whether the proposal would be inappropriate development in the Green Belt having regard to the National Planning Policy Framework (the Framework) and relevant development plan policies; ii) The effect of the proposal on the openness of the Green Belt; iii) The effect of the proposal on the living conditions of occupiers of 84 Galley Lane, with particular regard to light and outlook; and iv) If the scheme is inappropriate development, whether the harm by reason of inappropriateness or any other harm, is clearly outweighed by other considerations so as to amount to the very special circumstances necessary to justify it. Reasons Whether the proposal would be inappropriate development in the Green Belt 3. 82 Galley Lane is a detached 2 storey property in a closely-spaced ribbon of residential development that extends predominantly along one side of the road leading away from Barnet. The surrounding area is open countryside. No 82 is in the Green Belt. 4. Paragraph 143 of the Framework states that inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. Paragraph 145 of the Framework states that the Appeal Decision APP/N5090/D/19/3230079 2 construction of new buildings should be regarded as inappropriate in the Green Belt, subject to a number of listed exceptions. The relevant exception in this case is Paragraph 145 c) 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 DM15 of Barnet’s Local Plan (Development Management Policies) Development Plan Document Adopted September 2012 (the DMP) requires proposals in the Green Belt to comply with the Framework and it is consistent with the Framework policies for the protection of the Green Belt. 5. While the Framework does not define ‘disproportionate’, the Council’s Supplementary Planning Document: Residential Design Guidance Adopted October 2016 (the SPD) sets out that, as a guiding principle, the volume of the original dwelling should not be increased by more than 25% by external measurement. This calculation takes account of the cumulative effects of previous extensions and also includes unused permitted development rights and any extant consents to build. 6. The parties in this case have calculated the size of the original building in different ways. While the Council’s evidence refers to the footprint of the dwelling, the appellant refers to the internal floor area which includes both the ground and first floors. Irrespective of whether the baseline for the assessment is the footprint of the original building or its internal floor space, both parties agree that the proposal would result in an increase of more than 25% of the size of the original dwelling. 7. It is not clear why the appellant discounts the cumulative effect of the garage extension. However, even without it, the existing rear extension and appeal scheme alone would cumulatively represent a roughly 43% increase in internal floor space over the original dwelling. The Council has not provided any detailed calculations. Nevertheless, if the additions are considered in the context of the original footprint of the dwelling, which is smaller than the 2 storey internal floor area, then the percentage increase in the size of the original building would be clearly greater than the 43% increase calculated by the appellant. 8. Therefore, on the basis of the evidence before me, the appeal scheme would result in disproportionate additions over and above the size of the original building. For this reason, the proposal would be inappropriate development in the Green Belt and it would therefore conflict with Policy DM15 of the DMP, Policies CS1 and CS7 of Barnet’s Local Plan (Core Strategy) Development Plan Document Adopted September 2012 (the DPD) and the Framework. Openness of the Green Belt 9. The Framework advises that openness and permanence are the essential characteristics of the Green Belt. Openness is the absence of development and it has both spatial and visual aspects. 10. The appeal scheme would be located to the side of the property between the garage to the front and the existing extension to the rear. The area is already hard-surfaced and the proposal would not therefore result in a spatial loss of openness. 11. The extension would be approximately 10 metres deep, less than 3 metres wide and with a maximum roof height of some 3.1 metres. Notwithstanding the Appeal Decision APP/N5090/D/19/3230079 3 presence of the timber-framed carport, the proposal would represent an increase in the bulk of permanent development at this site. It would not be readily visible from Galley Lane, being screened by the garage. However, it would be clearly visible from the adjacent property, No 84. While modest in size, there would nevertheless be a visual impact as the result of the infilling of a gap to the side of the property, resulting in a minimal loss of openness of the Green Belt in this location. Living conditions 12. The proposal would extend along the shared boundary between Nos 82 and 84 Galley Lane. It would link the side elevations of the garage and the rear extension, creating an extensive length of wall that would be readily visible above the close-boarded boundary fence. Given its proximity to the boundary, and by virtue of its design, height and length, the extension would be visually obtrusive when viewed from No 84, particularly from the adjacent conservatory. Moreover, in combination with the rear extension, the cumulative length and height above the boundary fence would result in a sense of enclosure and consequent detrimental impact to the occupiers of the adjoining property. 13. Although single storey, the side elevation of the extension would be taller than the neighbouring conservatory. I accept that the conservatory will be shaded, at least during the early parts of the day, by the appeal property. However, while the proposal might not result in a significant loss of sunlight, given the close proximity and relationship of the side elevation to the neighbouring property, it would nevertheless result in a reduction of daylight in the adjacent conservatory. 14. Therefore, by virtue of its size and height, proximity to the boundary and cumulative impact in combination with the existing rear extension, the appeal scheme would result in harm to the living conditions of the occupiers of No 84, with particular regard to loss of outlook and light and a sense of enclosure. It would conflict with the residential amenity protection aims of Policies CS1 and CS5 of the DPD and Policy DM01 of the DMP and the SPD. Other considerations 15. It has been suggested that an extension of nearly the same size could be built using permitted development rights. However, even if permitted development rights are applicable at this site, no detailed plans of any such development have been provided. Moreover, there is little evidence to suggest that permitted development rights would be exercised in the event that the appeal was dismissed. Therefore, this does not appear to be a genuine fallback position and I give it limited weight accordingly. 16. The absence of objections to the proposal, including from the neighbouring occupiers of 84 Galley Lane, is a matter which carries neutral weight in my assessment. Green belt balance 17. I have concluded that the proposed dwelling would be inappropriate development in the Green Belt. It would result in a loss of openness, albeit minimal, of the Green Belt. These matters attract substantial weight. Appeal Decision APP/N5090/D/19/3230079 4 18. The proposal would result in harm to the living conditions of the neighbouring occupiers of No 84. 19. The Framework states that inappropriate development should not be approved except in very special circumstances. In this case, there are no other considerations that would clearly outweigh the harm to the Green Belt by reason of inappropriateness, loss of openness and other harm. Therefore, the very special circumstances necessary to justify the proposal do not exist. Conclusion 20. For the reasons set out above, the appeal should be dismissed. Sarah Manchester INSPECTOR