Appeal 3323426

The appeal is dismissed insofar as it relates to the erection of a side and rear roof extension to main roof slope and an extension above two-storey rear addition.

The appeal is allowed insofar as it relates to the erection of a single-storey side extension and erection of a rear/side ground floor extension, and front rooflight; and planning permission is granted for erection of a single-storey side extension and erection of a rear/side ground floor extension, and front rooflight at [site address] , Wandsworth [postcode] in accordance with the terms of the application, Ref 2022/4081, dated 4 October 2022, so far as relevant to that part of the development hereby permitted and subject to the conditions shown in the Annex to this letter.

An application for costs which is made by [name] against the London Borough of Wandsworth. This application is the subject of a separate decision.

I have taken the description of the development from the Council’s Decision Notice as this describes the different elements of the scheme in more detail. It is also noted that this description has also been used on the appellant’s appeal form.

The Council in their Planning Officer Report state that the proposed single-storey side extension and rear/side ground floor extension, and front rooflight would be appropriate and in accordance with the Development Plan Policies. I have no reason to dispute this opinion, and given that these elements are both functionally and physically severable from the roof extensions, a split decision is considered a suitable outcome. I acknowledge that the alteration to the roof of the rear wing was deemed acceptable by the Council, however this does not Appeal Decision: APP/H5960/D/23/3323426 appear to be physically severable from the rear main roof extension. Given the only matter in dispute refers to alteration to the main roof, this will be the focus of this letter.

It is noted that the Reasons for Refusal from the Council’s Decision Notice cited Policies DMS1, DMS8 and DMS9 of the Wandsworth Development Management Policies 2016 (DMPD). During the appeal process, the Wandsworth Local Plan (LP) has been examined, and then has been adopted by the Council on 19 July 2023 which supersedes the policies of the DMPD. The reasons for refusal also state the ‘publication version’ policies of the Local Plan, which are now fully adopted and carry full weight. I have therefore only referred to the adopted policies of the LP in this decision.

The main issue is the effect of the proposed alterations to the main roof of the existing building and the character and appearance of the locality; with special regard to the Wandsworth Common Conservation Area (CA).

Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 (PLBCA), in respect of development affecting conservation areas, states that special attention shall be paid to the desirability of preserving or enhancing the character and/or appearance of the area.

The appeal site is located along [address], which forms a number of streets in the locality that contains formally laid out speculative housing around the Common which appears to date from the late nineteenth century. The streets contain a mix of dwelling types situated in groups which may respond to the range of speculative builders, with common forms being groups of terraces, and groups of semi-detached dwellings. Despite different building types, the dwellings maintain similar setbacks from the street, similar materials, and high ornamentation in their design with many of the dwellings having corbelled eaves, decorative stone fenestration surrounds, the use of cream and gault bricks, and large chimney stacks that dominate the roofline.

The spaces and visual gaps in and around dwellings and to the first floor level in between properties enables glimpses to the tops of trees in rear gardens to be experienced and is a positive characteristic of the area alongside street trees and vegetated front gardens. Whilst there are limited examples of roof and side alterations which enclose the visual gaps and remove positive architectural features and present a poor appearance to the street scene; the original roof forms dominate and form part of the qualities that make up the local character and distinctiveness of the locality.

The appeal site appears to have been one of the characteristic semi-detached dwellings which have been constructed in a group of 3 pairs of semi-detached dwellings between No’s 57-65 (odd) where the appeal site lies to the centre pair. Each of the pair of dwellings maintains similar design characteristics with cream brick, hipped roof with central parapet, corbelled eaves, large chimney stacks and large canted bay window to ground floor. Gaps are present between the pairs of semi-detached properties, except between No’s 61 and 63 where a narrow dwelling has been erected within the gap. [name] acknowledge comments from the appellant’s Statement of Case (SoC) that the small infill Appeal Decision: APP/H5960/D/23/3323426 development to the gap in-effect makes the appeal site a terrace, the form and appearance of the pairs of semi-detached dwellings and roof forms do allow the historic proportions and designs of semi-detached forms to dominate and many of the remaining features are architecturally authentic to their historic origins as semi-detached properties. Whilst one could view the properties as either semi-detached or terraced, it does not change how extensions and alterations are assessed in terms of the characteristics and proportions of the existing dwellings, and the need for alterations to respond to the character of the building and the surrounding context.

In undertaking extensions and alterations to the roof of an existing dwelling, the Wandsworth LP Policy LP1 sets a number of design principles such as ensuring a design-led approach where new development ensures a high level of physical integration with their surroundings; ensure that scale and massing contributes to local spatial character; does not harm the amenity of occupiers and users; and is sympathetic to local characteristics, amongst others. LP Policy LP3 is related to the historic environment and seeks that proposals sustain, preserve and wherever possible, enhance the significance, appearance, character, function and setting of heritage assets. LP Policy LP5 applies specifically to residential extensions and seeks that development respects and/or complements the form, setting, period and detailing of the host building, is in keeping wit the with the character of the locality and the style of the existing building, amongst others. The design policies are supplemented by the Wandsworth Housing Supplementary Planning Document (SPD) which provides further guidance with regards to roof extensions such as rooves being an important feature of the urban scene and ensuring the extension is proportionate to the roof, with emphasis on preserving original features such as the pitch and chimneys of the roof.

The proposal would be situated towards the centre of the side of the hip of the roof and would have a mansard form that wraps around to the rear pitch, removing much of the pitch of the roof, along with the characteristic chimney stack, both elements of which are positive characteristics of this particular dwelling and within the group of three pairs of semi-detached dwellings. [name] appreciate that zinc is a high quality product, its use for the entire extension would present a dominant appearance to the roof form which would not provide subservience, and would draw attention away from the historic characteristics of the roof of the dwelling which are important for reinforcing the qualities of local character and distinctiveness. [name] acknowledge that design elements such as dropping the ridge and incorporating a setback to the centre of the roof have been employed to reduce visual bulk, these design elements are unsuccessful. The erosion of much of the pitch of the roof together with the wrap around mansard nature of the alteration, and loss of chimney stack would create a poor relationship to the existing building and how it is experienced within the locality.

I note comments in the appellant’s SoC that because the extension has low visibility from a public realm and is predominantly located to the rear that it would therefore cause no harm to the character and appearance of the CA. The duty provided under s72 of the PLBCA does not make any differentiation between whether the development is within the public or private realm, and an assessment of harm is not limited to tangible aspects such as views and should also incorporate intangible aspects. As such it is not appropriate to discount the contribution to the significance of the rear of the buildings to the CA, which as Appeal Decision: APP/H5960/D/23/3323426 described contribute to the significance of the CA, the status, and architectural authenticity and integrity of the existing building. [name] agree with the appellant that the front façade and plan form of the pairs of semi-detached dwellings may have been altered from the development of No.61a which fills the gap between the properties, the hipped roof forms along with their chimneys remain as a dominant component of the historic pairs of semi-detached dwellings, particularly with the infill having a parapet roof that sits under the eaves and being subservient of the adjoining pitched roof forms.

I also acknowledge extensions1 found in the surrounding area where large side and roof extensions have been permitted within the [name]. What is evident in these applications, are that the applications are considered on their merits and in the officer reports that have been submitted in relation to these applications, that officers at the time gave consideration to the significance and the character and appearance of the area where such extensions had become common place in these neighbouring streets. [address], such extensions are not characteristics of this locality, where consideration has been given to maintaining the architectural integrity and authenticity of historic roof forms and positive characteristics such as roof pitch and chimney stacks. As such the presence of extensions elsewhere does not provide adequate justification to the proposal for the appeal site.

In conclusion of this matter, the proposed alteration to the main roof of the existing dwelling would not be a suitable architectural approach which in turn would cause harm to the character and appearance of the existing dwelling and cause harm to the surrounding locality. The alterations would therefore be contrary to [name] LP1, LP3 and LP5, which is supported by the SPD, as described previously.

Taking the above into account, and whilst serious, the proposed first floor rear extension was found to cause ‘less than substantial harm’ to the significance of the CA within the meaning of the term in paragraph 202 of the National Planning Policy Framework (the Framework). Paragraph 200 of the Framework states that any harm to, or loss of, the significance of a designated heritage asset requires clear and convincing justification. Paragraph 202 of the Framework requires that, where a proposal would lead to less than substantial harm, the harm should be weighed against the public benefits of the proposal.

The appellant has not outlined any public benefits of the scheme. However, to me, the benefits of the scheme would deliver larger residential accommodation for the existing dwelling, as well as result in short term employment opportunities in the construction of the extension; all of which are important planning policy objectives. However, these benefits may also be present in a more appropriately designed scheme. That said, these benefits would not justify the harm I have identified.

I therefore find that the public benefits would not outweigh the harm caused to the significance of the CA. The scheme therefore conflicts with the Framework, which directs, at paragraph 199, ‘that great weight should be given to the asset’s conservation ... irrespective of whether any potential harm amounts to substantial harm, total loss or less than substantial harm to their significance’. 1 [name] 2014/7236: [address]; [name] 2022/0334: [address]; [name] 2022/4801: [address]; [name] 2019/4775 [address] Appeal Decision: APP/H5960/D/23/3323426

In conclusion on this matter, I consider the proposed development would cause less than substantial harm to the significance of the CA. It has not been shown that public benefits would outweigh this harm and so the proposal would conflict with the development plan.

For the reasons given above, I conclude that the appeal should succeed in relation to the rear and side single storey extensions and the roof light to the front roof plane. However, in relation to the alterations to the main roof, the appeal should be dismissed.

I have had regard to the context of the Framework and the National Planning Practice Guidance which advises that conditions should only be imposed where they are necessary, relevant to planning and to the development to be permitted, enforceable, precise and reasonable in all other respects. The Council has forwarded a list of proposed conditions should the appeal be allowed.

In respect of the side and rear ground floor extension and roof light, 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. Condition 3 seeks to approve materials, which is a necessary condition and meets the tests of conditions to achieve a suitable external appearance with the conservation area. The condition allows demolition to take place beforehand, and would therefore not be a pre-commencement condition requiring pre-authorisation by the appellant. Condition 4 seeks that the flat roof of the ground floor extensions are not utilised for sitting out, which is necessary and meets the test of conditions and seeks to avoid any harm caused to the living conditions of surrounding occupiers. Condition 5 seeks a suitable conservation rooflight that finishes flush with the existing roof plane which is necessary and meets the test of

The proposed single-storey side extension and rear/side ground floor extension hereby permitted shall begin not later than three [3] years from the date of this decision.

The proposed single-storey side extension and rear/side ground floor extension and front roof light shall be constructed in accordance with approved plans: • ‘Proposed Roof Plan and Site Layout,’ [name]. 514/101 [name], [name] 2022; • ‘Proposed Ground Floor Plan,’ [name]. 514/103, [name] 2022; • ‘Proposed Roof Plan and Site Layout,’ [name]. 514/101 [name], [name] 2022; • ‘[name],’ [name]. 514/106 [name], [name] 2022; • ‘[name],’ [name]. 514/107 [name], [name] 2022; • ‘[name],’ [name]. 514/108 [name], [name] 2022;

Prior to commencement of above ground works (excluding demolition), details and samples of materials proposed to be used on all external surfaces of the development hereby permitted shall be submitted to and approved in writing by the local planning authority. The development shall be carried out in accordance with the approved materials and thereafter so retained.

The roof area of the development hereby permitted shall not be used as a balcony, roof garden or similar amenity area and furthermore, no balustrades, railings or other means of enclosure or means of permanent access shall be erected on this area.

The rooflights hereby permitted, shall be of a conservation area specification i.e. in-line and flush within the roof pitch that they would be located.