Appeal 3334093

The Council has described the proposal as “erection of a single-storey ground floor rear/side extension, first floor rear extension, elevational alterations comprising replacement windows, insertion of rooflight, infill garage door with wall, replacement cladding and landscaping works”. This more accurately describes the proposal and is used below.

The appeal is dismissed insofar as it relates to the first-floor rear extension.

The appeal is allowed and planning permission granted for single storey rear extension, replacement windows and doors, replacement of roller garage door with a new wall and minor landscaping to the courtyard garden at [site address] in accordance with the terms of the application, Ref 2023/0527, 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, which for the avoidance of doubt only relates to the single storey ground floor rear/side extension, elevational alterations comprising replacement windows, insertion of rooflight, infill garage door with wall, replacement cladding and landscaping works, shall be carried out in accordance with the following approved plans: B.EX.0.1 (existing location plan), B.EX.0.2 (existing site plan), B.EX.2.1 (existing ground floor plan), B.EX.2.2 (existing first floor plan), B.EX.2.3 (existing loft plans), B.EX.2.4 (existing roof plans), B.EX.3.1 (existing front elevation), B.EX.3.2 (existing side (left) elevation), B.EX.3.3 (existing rear elevation), B.EX.3.4 (existing side (right) elevation), B.EX.4.1 (existing section 1), B.EX.4.2 (existing section 2), D.PR.0.1 (proposed site plan), D.PR.2.1 (proposed ground floor plan), D.PR.2.2 (proposed first floor plan), D.PR.2.3 (proposed loft floor plan), D.PR.2.4 (proposed roof floor plan), D.PR.3.1 (proposed front elevation), D.PR.3.2 (proposed side (left) elevation), D.PR.3.3 (proposed rear elevation), D.PR.3.4 (proposed side (right) elevation), D.PR.4.1 (proposed section 1), and D.PR.4.2 (proposed section 2).

The materials to be used in the external surfaces of the development shall match those used in the existing dwelling.

Prior to any works above ground level on the extensions hereby permitted the following details shall be submitted to and approved in writing by the Local Planning Authority: - a detailed specification including drainage layout and management and maintenance plan of at least one sustainable drainage system (e.g. water butts, raingarden, bioretention planter box, permeable paving). If soakaways (plastic modules and soakaway rings) are used an infiltration test must be carried out to ensure suitability and it must be demonstrated that there will be no increase in surface water flow being discharged off site and an overall reduction in peak flow rate and volume. - a scheme for flood resilient and resistant construction measures against surface water flood risk. The details shall be implemented in accordance with the approved schemes prior to the first use of the development hereby permitted.

The development shall not commence until a detailed survey, to include position, height and spread of canopy and root protection area of the preserved tree within the site boundary, and method statement to show how this tree will be protected during construction, has been submitted to and approved by the Local Planning Authority. The development shall be carried out in accordance with the approved details.

The Council’s objection to the appeal scheme relates only to the first-floor addition, that is the ‘rear dormer’ as originally described. Therefore, the main issue is the effect of this proposed addition on the character and appearance of the host dwelling and the [address] and Mapledene Conservation Area.

The appeal site is a modern, two-storey, end of terrace property located at the southern end of [address] at its junction with [address]. The dwelling is part of a terrace of three dwellings of similar appearance of mainly brickwork elevations and tiled roofs; the front elevation is almost symmetrical in appearance, but the dwelling on the appeal site has a hipped end roof rather than pitched as on the others and the other end (flank) elevation of the terrace is finished with a parapet roof. Both end dwellings also have ‘matching’ rear additions (outriggers) with catslide roofs. The dwelling on the appeal site has a wall along part of the southern elevation with high parapet forming the side wall to part of the rear extension, the remainder of which is formed by the side wall beneath the sloping roof of the catslide, which is finished in timber cladding. The appeal site dwelling also had a single storey side/rear sunroom / bathroom addition, which was in the process of being demolished at the time of my site visit.

A roller shutter garage door is attached to the rear extension which currently gives access to the small rear amenity area from [address] with the remainder of that short boundary marked by a wall with trellis above. A large sycamore tree which is the subject of a Tree Preservation Order lies close to southern boundary. Adjacent to the rear of the site is a modern detached dwelling of brick elevations and flat roof design.

The appeal site lies at the south-eastern edge of the extensive conservation area which is mainly characterised by older Victorian terraces with a mixture of pitched roofs and front parapet roofs, set close to the road frontages. These terraces are interspersed with large, flatted buildings of more recent age such as those at the [name]. In the vicinity of the appeal site the significance of the heritage asset is mainly derived from these Victorian terraces and their general uniformity of style and appearance.

The proposed first floor addition would be set into the existing catslide roof of the rear projection. It would have a flat roof, the top edge of which would be set into and extend just above the eaves of the existing rear hipped roof and would be externally finished in ‘burnt wood’ cladding. It would extend across virtually the whole width and depth of the existing catslide roof. In terms of its design and finished appearance it would contrast noticeably with the existing dwelling, which although of recent construction, reflects many of the ‘traditional’ features of the area such as the hipped roof form, parapet edge roofs and brick elevations with stone ‘mullions’ around the windows.

The Council’s Residential Extensions and [name] (2009) (SPD) states in respect of rear extensions that they should be subordinate to the principal building and reflect its form and materials. It also states that rear dormers should be well spaced, positioned within the existing roofslope set in from party wall and down from the ridge and should generally not exceed half the width of the roof. Whilst the proposed addition would be at first floor level and not at the higher main roofslope level where most of the examples in the SPD are shown, it would fail to comply with these guidelines.

It would be visible in the street scene of [address] albeit partly screened by the existing parapet wall along the southern boundary. Given its size, design and position with somewhat awkward ‘join’ with the existing roof edge, and despite its lower roof height and uses of contrasting external materials, it would appear as an unduly large and unsympathetic addition which would fail to complement the design and appearance of the existing dwelling. As a result, it would fail to conserve or enhance the conservation area and would be harmful to the character and appearance of the wider area.

The level of harm arising would be less than substantial and paragraph 208 of the National Planning Policy Framework (the Framework) states that this harm should be weighed against the public benefits of the proposal. Whilst the proposal would provide enhanced accommodation this would only be of limited public benefit and would not outweigh the harm identified.

The proposed rear dormer therefore conflicts with Policies LP1, LP3 and LP33 of the Hackney Local Plan 2020 and Policies D4 and HC1 of The London Plan which seek development of the highest architectural and urban design quality that responds to local character and context, that preserves or enhances the character and appearance of the conservation area and conserves the significance of heritage assets. It also fails to satisfy the Council’s SPD.

As noted above the Council has not raised an objection to the other elements of the scheme and I concur with these findings, noting that the single storey side/rear extension would replace the existing sunroom / bathroom and, overall, the changes would preserve the character and appearance of the conservation area. As these elements are separate and physically severable, I intend to issue a split decision in part allowing and in part dismissing the appeal.

The Council has suggested conditions to require accordance with the approved plans and use of matching materials both of which I agree are necessary in the interests of clarity and visual amenity. Further conditions to secure details of sustainable drainage measures and protection of the preserved tree on the site are also necessary to address climate change and ensure the future heath of the preserved tree. I have reviewed the suggested wording against the tests in Framework paragraph 56 and amended them accordingly.

I conclude that the appeal should be dismissed in part and allowed in part.