Appeal 3267799

The appeal is allowed and planning permission is granted for the demolition of part of an existing ground floor WC to the rear of the house and the erection of a single storey rear extension at [site address] in accordance with the terms of the application, Ref 2020/2210, dated 1 September 2020, and the plans submitted with it, subject to the following

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: Location Plan; Block/Site Plan; drawing ref. 001 [name]; 002 [name]; 003 [name]; 004 [name].

The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building.

The main issue in this case is the effect of the proposal on the living conditions of the occupiers of No.[address], with particular regard to light and outlook.

The appeal property is a semi-detached house on the south-west side of [address]. It is proposed to extend at ground floor to the rear across the full width of the house, infilling an existing side return. The extension would be offset from the shared boundary with its non-attached neighbour at No.[address] (No.23) by around 1m. No.23 is a two-storey house with a relatively long rear garden. There are patio doors to the ground floor of the main rear elevation and a window to the return elevation that directly faces the appeal property. Both are understood to serve the kitchen of No.23.

The Council’s Design and Character Supplementary Planning Document (2012) (SPD) uses the 45-degree rule as a ‘useful tool’ in assessing the effect of new development on the amenity of neighbours. The guidance is that a single storey extension should not impinge on a 45-degree line from the outer edge of the neighbours nearest habitable window at a distance of less than 8m. The proposed extension would have a depth of around 8m from the principal rear elevation of the appeal property and, taken from either the outer edge or centre of the patio doors of No.23, would clearly impinge on the 45-degree line at a distance of around 4.8m. There would, therefore, be a clear technical breach with the SPD guidance.

However, these standards must be set in context and the SPD ([name]: [name]) states at paragraph 1.15 that each application must be treated on its own merits. As part of my site visit, I was able to consider the relationship of the proposed single storey extension with the rear patio doors and window of No.23. There is an existing wall along the shared boundary with No.23 that is at least 1.8m in height and would run almost the full depth of the proposed extension. There is also a reasonable separation distance between the main rear elevation of No.23 and the shared boundary. The separation distance, in combination with the height of the wall, means there would be no significant loss of light to the patio doors on the rear elevation.

The SPD recognises that the loss of light to an adjoining dwelling can be more noticeable where an extension is to be directly south. In this case, the extension would be located to the north-west of No.23. Because of this orientation, the proposal is only likely to cause some loss of sunlight during the late afternoon or evening.

The proposed extension would be a more prominent feature than the existing boundary wall, seen around 1m above it at the depth of 8m from the existing main rear elevation. However, the outlook from the patio doors would continue to be over the relatively long garden of No.23 and would retain a reasonably open aspect. Therefore, whilst the proposed development would result in some additional sense of enclosure, it would not have a particularly overbearing impact on the existing occupiers of No.23.

In terms of the window on the return elevation of No.23 facing the appeal property, the relatively low height and flat roof design of the extension means that the outlook from this window would not significantly change, remaining over the boundary wall. The existing boundary wall is already likely to restrict some light to the window but, given the height of proposed extension around 1m above the shared boundary there would likely be some further loss of light to this window. I note however that the window is a secondary window to the dual aspect kitchen, and I am not persuaded that this would materially affect the living conditions of the neighbours.

Consequently, despite a breach of the SPD’s 45-degree guidance, the appeal proposal would not cause harm to the living conditions of the neighbours at No.[address]. It would therefore accord with Policy DM2 of the Elmbridge Local Plan Development Management Plan (2015) which, amongst other things, requires proposals to protect the amenity of adjacent users and offer appropriate outlook and adequate daylight, sunlight. The proposal also aligns with the guidance at paragraph 127 of the National Planning Policy Framework where it requires proposals to maintain a high standard of amenity for existing users.

In addition to the standard time limit condition, I consider it necessary to include a condition referencing the approved drawings for the avoidance of doubt and in the interest of certainty. A condition relating to the construction of the extension in materials to match the existing building is also necessary to safeguard the character and appearance of the area.

For the reasons given above, the appeal is allowed.