Appeal 3284543

The appeal is dismissed.

An application for a full award of costs has been made by [name] against the Council of the London Borough of Enfield. This application will be the subject of a separate decision.

The main issues are the effects of the proposed extension upon the character and appearance of the dwelling and its surroundings and upon the amenity and living conditions of the occupiers of the adjoining properties with regard to outlook, light and sense of enclosure.

The appeal concerns a 2-storey house within a short terrace of 5 such houses in an established residential area. It benefits from an existing full-width, flat-roofed single-storey rear extension about 2.5 m in depth. This borders the lowest point of the rear garden which slopes up away from the house. The adjoining terraced houses on each side (nos 1 and 5) have similar extensions which reach about 3 m in depth beyond their original rear elevations. These 3 rear extensions step up in height, with the one at no. 5 being the highest, mirroring the main eaves line across the terrace.

The appellant seeks to add a further flat-roofed single-storey extension to the rear of the existing extension. This would also extend across the full width of the plot and, in combination with the existing extension, would result in a projection from the original rear building line of the property of about 5.3 m.

Policy DMD 11 (part 2) of Enfield’s Development Management Document November 2014 (DMD) states that single-storey extensions must not exceed 3 m in depth beyond the original rear wall of a terraced property. Paragraph 4.5.3 of that document indicates that this will apply regardless of the depth of any adjoining extensions, although an extension of greater depth may be permitted to secure a common alignment of rear extensions. This development plan policy does not restrict the freedom of householders to seek larger home extensions through the prior notification arrangements available in the general permitted development order. This is not a marginal case in terms of depth insofar as DMD Policy DMD 11 is concerned and the scheme would not secure a common alignment of rear extensions.

This proposed second rear extension, in combination with the first, would project significantly from the rear of the original dwelling across its full width and appear disproportionately large. Substantial depth, bulk and massing would be added to the rear elevation of the host property which is clearly visible in views from the rear of several nearby residential properties. There would be an adverse visual impact, in conflict with Policy DMD 11 (part 1) of the DMD, as the proposed development would appear unduly dominant and out of scale with the host dwelling and the neighbouring houses. It would also disrupt the reasonably settled line of more modest ground floor rear extensions hereabouts.

I find on the first main issue that the proposed extension would be harmful to the character and appearance of the dwelling and its surroundings. As the proposed development would fail to: deliver good design; have appropriate regard to its surroundings; maintain and improve the quality of the built environment; and avoid an adverse visual impact, there would be conflict with the aims of Policy D4 of the London Plan March 2021, Core Policy 30 of [name] 2010 and [name] 11 and DMD 37 of the DMD. Good design is also plainly a cornerstone of the National Planning Policy Framework (the Framework).

With regard to the second main issue, with reference to DMD Policy DMD 11 (part 2), single-storey rear extensions must not exceed a line taken at 45 degrees from the mid-point of the nearest original ground floor window to any of the adjacent properties. This measure is used by many Councils in my experience. It seems reasonable to consider the closest existing neighbouring ground floor windows when houses have already been extended at the rear.

The Council says the extension would intercept that 45-degree line in respect of both neighbouring properties but there are no illustrations in the officer’s report, the submitted plans or the appellant’s statement. My own study of the plans leads me to the view that any encroachment into the 45-degree line would be very marginal in respect of both neighbouring houses. Whilst the appellant has referred to the technical standards used by the Building Research Establishment, no technical report has been submitted. The stated reasons for not doing so are not particularly robust. 2

As the proposed rear extension would be lower than the one at no. 5 and would no higher than the boundary fencing and vegetation growing over it from inside the boundary of no. 5, I consider that it would not create an unacceptable sense of enclosure, cause overshadowing or appear visually overbearing when seen in the outlook from the neighbouring back garden and rear-facing rooms at no. 5. The experience of [address] as being set within a good-sized back garden which faces east would endure.

The proposed rear extension would be higher than the one to the rear of no. 1, the existing common boundary treatment and any boundary structures that could potentially be erected using permitted development rights. Given the orientation of this adjacent property and the layout of its rearmost room with various windows and rooflights, I doubt that the occupiers would notice any material loss of daylight or sunlight. However, the proposed extension would loom up over the boundary and be sufficiently close to the nearest and principal ground floor opening in the rear of no. 1 to appear as a dominant, oppressive and enclosing feature in the outlook from that opening.

I find on the second main issue that the proposed development would have unacceptable impacts upon the amenities and living conditions of the neighbours at [address], with regards to outlook and sense of enclosure. As such, there would be conflict with the aims of the same development plan policies I listed in paragraph 8 above, in particular Policy DMD 11 of the DMD. Similarly, there would not be compliance with the Framework which seeks to ensure developments create places with a high standard of amenity for existing and future occupiers.

My findings on the main issues are decisive to the outcome of this appeal. There is conflict with the development plan. The harm cannot be mitigated by the imposition of planning conditions and it is not outweighed by other material considerations. For the reasons given above and taking into account all other matters raised, I conclude that this appeal should not succeed.