Appeal 6010302

The appeal is dismissed.

The main issue is the effect of the proposal upon the character and appearance of the host property and wider street scene.

The appeal relates to a two-storey, semi-detached dwelling set within a stretch of similar style and aged properties to the west side of [address] and facing green open land opposite. The semi-detached pairs (Nos 17-51 odd) lie between [address] to the south and [address] to the north and would originally have been separated by the width of a side driveway to each, leading to a detached garage in a recessed position. This arrangement is still evident for some, including at No 39, with a variety of side additions and alterations to others.

The appeal proposal seeks to remove the existing garage and to erect a part single-storey, part two-storey front, side, and rear extension. At ground floor level, the extension would wrap around the rear and side elevations of the dwelling projecting 4.25m deep beyond the dwelling’s rear elevation; extending to the side up to the common boundary with No 41; and would project forward to link with an existing front porch with a matching lean-to roof over. At first-floor level the extension would project the gabled form of the dwelling sideways up to the shared boundary with No 41 but with a set back of 1.5m from the main front elevation, and would project 3.3m to the rear with a return across part of the original rear elevation and a hipped roof over.

The Council’s Residential Extensions Guidelines was adopted as a Supplementary Planning Document (SPD) in 2010 and seeks to provide basic design principles, amenity considerations, and guidance on specific types of extensions to ensure that the residential areas within Slough remain good places to live and are not adversely affected by inappropriate extensions.

The Council has no specific concerns relating to the extension to the rear, which they are satisfied complies with the relevant guidance of the SPD when considered alone. I have no reason to disagree.

In relation to single-storey side extensions, amongst other things, the SPD advises at EX8 that they should not project forward of the front main wall of the property. In particular it states that those projecting forward of the front main wall of the existing house and “tying into” an adjoining single-storey front extension will not be permitted. In relation to two-storey/first-floor side extensions, amongst other things, the SPD advises against possible “terracing” effects and at EX11 states that they should be set off the side boundary by a minimum of 1m. The SPD goes on to consider where a two-storey/first-floor side extension may already exist and is built up to the boundary. In those circumstances it advises that planning applications for similar extensions on the neighbouring property will not normally be permitted unless a minimum two metre gap can be achieved at first-floor level between the two extended properties.

Of the nine pairs of semi-detached houses along this stretch of [address], only two properties (Nos 33 and 41) have been extended to the side at two-storey up to the boundary that is shared with a similar neighbouring dwelling. The example at No 41 is adjacent to the appeal site and, similar to No 33, has in isolation significantly narrowed the original gap between these two properties, despite the deep recess at first-floor level. Nos 17 and [address] appear both to have been extended at two-storey to the side, but each of these dwellings sits at opposite ends of the row, with no perceived terracing impact within the street scene. I observed only two other properties that had been extended to the side at two-storey. In both cases, at Nos 29 and 43, the first-floor element had been set around 1m away from the common side boundary with its neighbour.

I have not been provided with any of the planning history to any of the various side extensions that have taken place along [address]. Nevertheless, despite these, and numerous single-storey side extensions to others that fill the original gap to their respective side boundaries, each semi-detached pair remains separate and visually distinguished from each other due largely to the retained space between them at first-floor level. This imparts a clearly perceived and pleasing rhythm to the street scene.

The appeal proposal would be the first of its kind within this group to result in the full erosion of the gap at first-floor level between neighbouring properties. Notwithstanding the recessed position of the first-floor side addition, there would be a clear and uncharacteristic terracing effect between the semi-detached pairs at Nos 37/39 and 41/43. By so doing, the proposal would introduce a form of development the SPD specifically identifies and advises against. More importantly, due to the lack of any physical separation between the side walls of Nos 39 and 41, the proposal would appear cramped and out of keeping with the established pattern of development within the street scene.

The forward projecting ground floor part of the side extension would fuse with the existing porch to create a 5.2m wide front addition overall. Whilst this approach, along with its depth, would further conflict with the SPD where it gives advice for single-storey side and front extensions, I am not persuaded that this element alone would appear as an overtly dominant feature when considered in relation to the increased proportions proposed for the dwelling overall. However, there would be a poor marriage between the single-storey element’s area of flat roof beyond the forward projecting mono-pitch, such that the combined form of the side extension as a whole would appear poorly conceived and unsympathetically related to the simple architectural composition of the original dwelling.

Overall, I find that the configuration of the side extension would be harmful to the character and appearance of the appeal property and, that due to its siting close to the boundary, there would be harm to the character and appearance of the street scene. As such, there would be conflict with Core Policy 8 of the Council’s Core Strategy, adopted in 2008, and Policies H15, EN1 and EN2 of The Local Plan for Slough, adopted in 2004, which between them seek to ensure high quality of design, including for house extensions, which is compatible with the original dwelling and is in-keeping and respectful of its surroundings. For the same reasons there would be conflict with the National Planning Policy Framework’s policies for achieving well-designed places.

The appellant has drawn my attention to a planning permission ([name]/17121/000) granted for No 39 in 2017 for development described as ‘Demolition of existing garage & construction of a single storey side & rear extension & front porch’. Although not implemented and now lapsed, the scheme previously approved was for single-storey additions only and bears little relationship to the appeal scheme.

I have taken note of terraced properties elsewhere within the locality, particularly along [address], but these are obviously buildings of different typology and origin and draw no comparison with the semi-detached dwellings along this part of [address].

For the reasons given above, the appeal is dismissed.