Appeal 3281666

The appeal is dismissed.

The main issue is the effect of the proposed development on the character and appearance of the host property and the surrounding area.

The appeal property is a semi-detached dwelling located on a prominent corner plot at the junction of [address] and [address]. Due to this location, the dwelling benefits from a large garden which wraps around the side of the property, which gives a strong sense of openness to the street scene. In terms of design, the dwelling has a pitched roof and red brick exterior, both of which are consistent with the appearance of its adjoining neighbour. This design is also reflective of other dwellings in the immediate vicinity. Whilst many properties along the road have been extended to the side, these common characteristics give the houses in this area a degree of uniformity which contributes positively to its prevailing character.

The proposed development would introduce a two-storey side extension to the dwelling, together with a single storey extension at the rear. The existing frontage of the dwelling has a width of approximately 5.6 metres, and the side extension would extend this by approximately 5 metres. This would almost double the existing frontage, and would far exceed the guidance set out in the Council’s Extensions’ SPD1 ([name]), which states side extensions should “extend no more than half the width of the principal elevation”. Consequently, and even accounting for the side extension on the adjoining dwelling, the scale of the proposed development would significantly imbalance the pair of semi-detached houses, upsetting any sense of symmetry between 1 [name] & Alterations Supplementary Planning Document, October 2011 the two properties. This imbalance would be further exaggerated by the windows on the frontage of the side extension, which would essentially mirror the fenestration arrangement on the existing dwelling. As a result, the extension would appear more akin to a separate dwelling, which would further exacerbate the mismatch in size with its adjoining neighbour.

The side elevation of the appeal property currently shares a coherent building line with the front elevations of the bungalows to the rear, which face out on to [address]. The increased width of the proposed development would extend well beyond this established building line. This would further contravene the guidance set out in the [name], which is clear that “extensions at or adjacent to corner plots should not extend beyond the building lines of properties on all adjacent roads”. As a result, the development would interrupt the pattern of development in the area, thereby appearing particularly prominent in the street scene, which would further exacerbate the issues associated with its scale. This prominence would be especially apparent when approaching the property along [address] from the west, harming this element of the street scene in particular.

For these reasons, the development would harm the character and appearance of both the host property and the surrounding area. The development would therefore conflict with Policy DE1 of the Swindon Borough Local Plan 2026, which requires new development to respond properly to surrounding built form, specifically in terms of siting, orientation, scale, massing and materials. For the reasons set above, the development would also conflict the provisions of the [name]. Finally, the development would conflict with the overarching design objectives of the National Planning Policy Framework (2021).

I acknowledge that numerous dwellings along [address] have been extended to their side. However, the extensions at nos. 5, 16 and 20 are all substantially narrower than the development proposed, ensuring no significant imbalance with their adjoining neighbours. In terms of nos. 10 and 14, whilst these extensions are larger in scale, they can be accommodated more easily in this location without upsetting any established building lines with properties to their rear.

The side extension would be set back from the principal elevation at first floor level, and its ridge would sit below the ridge of the existing property. Whilst these factors would ensure an element of subservience between the extension and the host property, they would not overcome the imbalance between the appeal property and its adjoining neighbour which would be attributed to its increased width.

The proposal would conflict with the development plan as a whole and there are no other considerations, including the provisions of the Framework, which outweigh this finding. Therefore, for the reasons given, the appeal should be dismissed.