Appeal 3309878

The appeal is dismissed insofar as it relates to the two storey side extension; first floor rear extension, single storey rear extension and associated external alterations.

The appeal is allowed insofar as it relates to the outbuilding at rear for use as gym / office (demolition of attached garage) and planning permission is granted for an outbuilding at rear for use as gym / office (demolition of attached garage) at [site address] in accordance with the terms of the application, [name]/0401/22, dated 7 February 2022, so far as relevant to that part of the development hereby permitted and subject to the following conditions:

The proposed rear outbuilding hereby permitted shall begin not later than three [3] years from the date of this decision.

The proposed rear outbuilding shall be constructed in accordance with approved plans: • ‘[name], Side, Rear and [name],’ [name]-08L, Dated 02.01.2022; • ‘Proposed Site Plan,’ [name]-04L, Dated 02.01.2022; • ‘Proposed Ground Floor Plan,’ [name]-07L, Dated 02.01.2022;

The materials to be used in the external surfaces of the rear outbuilding shall match those used in the existing building.

The Council in their Planning Officer Report state that the rear outbuilding would be appropriate and in accordance with the Development Plan Policies. I have no reason to dispute this opinion, and given that this element is both functionally and physically severable from the side and rear extensions, a split decision is considered a suitable outcome. Given the only matter in dispute refers to the side and rear extensions, this will be the focus of this letter.

The main issue is the effect of the proposed side and rear extensions upon: • The existing building and the character and appearance of the locality; and • The living conditions of No.[address], with particular regard to access to light, and sense of enclosure.

The appeal site is located along [address], which forms a number of streets in the locality that contains formally laid out speculative housing which appears to date from the mid-late twentieth century. The local area predominantly contains pairs of semi-detached dwellings which have a symmetry in their placement with a consistent building line and setback with small front gardens with some dwellings having low boundary walls. The spaces and visual gaps in and around dwellings and to the first floor level in between properties over garages experience glimpses to the tops of trees in rear gardens are experienced and is a positive characteristic of the area alongside street trees and vegetated front gardens. On my site visit I noticed very similar designs, particular those along [address] are two storey, main hipped roof with red clay tiles, with either forward protruding gables with bow windows and mock timber gables, or two storey canted bay windows. The materials are also largely consistent and comprise of brick construction at ground level with render to the upper level. Whilst there are a limited examples of hip to gable roof extensions which present a poor appearance to the street scene, the original hipped roof forms dominate and form part of the qualities that make up the local character and distinctiveness.

The appeal site appears to have been one of the characteristic semi-detached dwellings, however due to the conversion of the hip-to gable end, has an a-symmetrical appearance within the street scene and an elongated appearance when compared to the surrounding buildings and the other half of the semi-detached dwelling. Despite this, the visual gap at first floor level is maintained and assists in reinforcing the spacious qualities of the locality.

In undertaking extensions and alterations to existing dwellings, the [name] 2012 (CS) Policy CS1 (B) seeks that new development responds positively to the local and historic context in terms of design, spacing, density and siting which reinforces positive attributes of local distinctiveness. Policy DM1 of the Harrow Development Management Policies Local Plan (LP) also seeks to establish high quality design that has regard to massing, bulk, scale and height and their relationship to the surrounding layout. These policies are supported by a Residential Design Guide Supplementary Planning Document (SPD) which provides further guidance and advice with regards to appropriate design principles employed in extensions and alterations. Additionally, the Appeal Decision: APP/M5450/D/22/3309878 London Plan Policy D3 is a relevant consideration in that this policy introduces a design-led approach in order to achieve appropriate development.

The proposal would extend the already elongated roof form to the boundary and would further accentuate the a-symmetry of the existing roof form which would present as an awkward extension to the existing pair of semi-detached dwellings and to the greater locality. [name] acknowledge that design elements such as dropping the ridge and incorporating a setback from the front of the dwelling have been employed to reduce visual bulk, these design elements are unsuccessful. The erosion of much of the visual gap would also remove the key gaps and spaces in and around the dwelling, and would create a poor relationship to the existing buildings within the street scene.

The two storey side extension would mean that there would be the erosion of much of the visual gap to the side and rear, which is a positive characteristic of this particular locality. The proposed extensions would create a materially larger dwelling and form unlike anything around and could not be seen as being a subservient addition when considering the proposed form and relationship of dwellings and the spaces in and around the dwellings which form positive characteristics. The proposed extension when experienced with the remaining half of the semi-detached dwelling would have a substantially larger mass and visual bulk in the street scene and create a dwelling and built form that would have an awkward and cramped appearance with loss of spaciousness in and around the dwelling when experienced on the appeal site.

Turning to the first floor rear extension, the alteration would have a pitched roof form that would intersect with the rear dormer. The SPD seeks that rear dormers are separate and contained within the existing roof form, and setback from the sides, eaves and ridge of the roof. However, in this case the enlargement of the first floor rear extension clutters the form of the existing dormer window and presents an awkward juxtaposition to the roof which appears cramped and lacking subservience due to its depth, placement and design.

The ground floor rear extension would be very long and to the Council’s calculations would extend approximately 5.1 metres past the rear elevation of the neighbouring dwelling at No.47. The SPD seeks that consideration is given to the existing site constraints and the established character of the area and the pattern of development. Whilst there is evidence of rear extensions to existing dwellings in the locality, none appear to be this long. Whilst the extension has been setback from the boundary and contains a flat roof to try and make the extension subservient, the visual bulk of the extension when combined with the existing rear extension would be almost as deep as the main component of the dwelling. I am therefore not convinced that the proposed single storey rear extension would be subservient and would be detrimental to the character and appearance of the existing building, the established character of the area and the pattern of development of the locality.

In conclusion of this matter, the proposed two storey side, first floor and ground floor rear extensions would not be a subservient alteration which would result in the loss of visual gap and be detrimental to the character and appearance of the existing building and the greater locality. The side and rear extensions would therefore be contrary to CS Policy CS1.B, DMP Policy DM1 A, DM1 B (a), (b) and (c) Policy D3 (D(1) and (11)), which is supported by the Appeal Decision: APP/M5450/D/22/3309878 SPD. Additionally the proposal would be contrary to London Plan Policy D3 as described previously.

No.[address] is part of a neighbouring pair of semi-detached properties. This dwelling is two storeys tall and contains a single storey garage between the boundary of the appeal site and the dwelling. The garage commences at the front façade of the neighbouring dwelling and projects along the boundary to the rear façade. The rear of the neighbouring dwelling does not contain any further extensions with the side boundary with the appeal site aligned with vegetation. There are windows on the ground and first floor of the rear façade of the neighbouring dwelling which appear to access habitable rooms, there are also two obscurely glazed windows to the side elevation as well as a window on the side elevation front corner of No.47 at first floor level.

Beginning with the first floor side/rear extension, the SPD exercises caution with regards to extensions and specifies considerations such as setback, length of extensions and that each application should be assessed on its merits. The proposed side and rear extension would project past the rear façade of the neighbouring dwelling along the boundary. Given that the existing hipped roof of the appeal dwelling has been changed to a side gable, the first floor side gable would be constructed along the side boundary and at the rear façade would change into a lower blank façade along the boundary with shallow pitched roof and end gable facing the rear of the property. The side and rear extension would present a large, elongated and tall blank wall along the side boundary of the appeal site. This would present an overbearing and a blank, dominant appearance to the neighbours at No.47. [name] appreciate that the neighbouring garden is wide, the proposed wall along the boundary would be detrimental to the living conditions of the neighbouring residents utilising their garden. The poor outlook and sense of enclosure would continue to the windows to the rear of this neighbouring property at both ground and first floor levels to the rear façade, causing detriment to the living conditions of the neighbouring occupants.

With regards to overshadowing and the loss of light, no evidence such as a daylight report has been submitted that provides technical explanation of the current conditions. However, given the direction of the sun in relation to the proposed rear extension, any shadow cast would appear be towards the front of the property, rather than the rear. As such, there would not appear to be any detrimental overshadowing caused by the first floor side and rear extensions towards to the neighbouring property.

Turning to the single storey rear extension, the SPD recommends a ‘two-for-one’ rule is applied that for the increased depth beyond 3 metres should be setback off the boundary twice its additional depth. The proposed extension would be setback from the boundary by 1 metre. I agree that this would be an appropriate measurement to apply in these circumstances. The one metre setback does present some relief from the increased built form, however when considering the cumulative depth of the extension with the existing rear extension, the built form and visual bulk would be considerable. The length, height and lack of appropriate setback would have an overbearing appearance to the neighbouring dwelling at No.47 which would affect their outlook. For similar reasons as stated with regards to the first floor rear extension, due to Appeal Decision: APP/M5450/D/22/3309878 the direction of the sun, I do not believe that there would be detrimental overshadowing or loss of light caused as a result of the ground floor rear extension.

Consequently, and in conclusion of this matter, whilst I have agreed with the appellant with regards to there being no adverse detriment cause by loss of light and overshadowing, this would not outweigh the detriment caused with regards to sense of enclosure and outlook. As such, the proposed scheme would be contrary to DMP Policy DM1 (which seeks that development not impact upon residential amenity), which is supported by the SPD, and Policy D3.D(7) (which seeks to take a design approach in ensuring the living conditions are protected in new development).

I note that the Reason for Refusal mentions Core Strategy Policy CS1 (which concerns housing delivery and place shaping) does not appear to be related to the assessment of living conditions and are therefore not relevant to the consideration of this matter.

For the reasons given above, I conclude that the appeal should succeed in relation to the rear outbuilding. However, in relation to the side and rear extensions, the appeal should be dismissed.

In respect of the rear outbuilding, it is necessary to have the standard conditions of the standard time limit for the avoidance of doubt; and the extension to be constructed in accordance with the approved plans is also necessary as this provides certainty to the scheme which has been approved. A matching materials condition is required in order to be appropriate to the existing building and the character and appearance of the locality.