Appeal 6000151

The appeal is dismissed.

At the site visit I observed that the proposed development has already been carried out. I have determined the appeal on this basis.

During the course of the appeal the Council adopted the Barnet Local Plan 2021 – 2036 (adopted 2025) (Local Plan) which replaces the previous Local Plan (2012)1. The main parties were provided with an opportunity to comment on its relevance to the appeal. I have taken the comments received into account.

The main issue is whether the development preserves or enhances the character or appearance of the Watling Estate Conservation Area.

The appeal site comprises [site address] (No 64), a 2-storey mid-terrace dwelling situated in a predominantly residential area. The site is within the Watling Estate Conservation Area (conservation area). The Planning (Listed Buildings and Conservation Areas) Act 1990 (as amended) provides at s72(1) that with respect to any buildings or other land in a conservation area, special attention shall be paid to the desirability of preserving or enhancing the character or appearance of that area.

As explained in the Watling Estate Conservation Area Character [name] (adopted 2007), the significance of the conservation area, when considered as a whole, derives in part from its distinctive character in terms of its layout, form, scale and building designs, including the houses all being similar in scale and form and the main materials and architectural details adopted being 1 Comprising the [name] and Development Management Policies Development Plan Documents. based on the specific vernacular architectural style of the Arts and Crafts movement. No 64 contributes towards the significance of the conservation area by virtue of its modest scale and its architectural form which complements the terrace of which it forms a part, which consists of dwellings of a similar scale and architectural design.

The development comprises roof alterations, including a rear dormer extension, a front rooflight, and the replacement of roof tiles. The rear dormer extension is attached to the built-out rear dormer at [address] (No 66), to which No 64 is adjoined. It spans across virtually the whole width of the rear roof slope of No 64, in conflict with paragraph 14.33 of the SPD2 which provides that, amongst other things, dormer roof extensions should not occupy more than half the width of the roof slope. Moreover, its height equals that of the ridge of No 64, and with a depth of approximately 3.6 metres, it constitutes a very sizable addition to No 64. It clearly does not comprise a subordinate feature on the roof, as advocated by paragraph 14.33 of the SPD.

Apart from the above-mentioned continuation of the rear dormer extension at No 66, I observed that none of the other dwellings within the terrace have been extended at roof level. Due to its considerable size and scale, the rear dormer extension accordingly appears as an overly-dominant feature which has disrupted the largely unaltered and uncluttered rear roof forms present on the terrace.

Taking all of the above into account, the development serves to undermine the distinctive architectural character of the conservation area, including the evident similarities between terraced dwellings in terms of their scale and form. Although the rear dormer extension is not visible from within the [address] street scene and hence the wider public realm, it is from the rear gardens of nearby dwellings and from the upper-floor windows of the dwellings to the rear of the site. As such, whilst the architectural integrity and the remaining historic elements of the front elevation of No 64 has been preserved, and the position and proportion of the windows and materials of the rear dormer extension are appropriate in their context, the development has nevertheless undermined the experience of the conservation area when seen from these viewpoints.

It is recognised that the harm identified to the conservation area is localised and is accordingly less than substantial within the terms of the Framework3. Given the unambiguous adverse impacts identified to both No [address], the extent of the harm within this category is substantial. This harm must be given considerable importance and weight. The Framework requires that it is weighed against the public benefits of the development.

The enlarged accommodation at No 64 mainly brings benefits of a private nature. On the other hand, the public benefits of the development are limited, meaning that they merit little weight. They do not outweigh the harm identified, taking account of the great weight given to the conservation of the designated heritage asset, as per paragraph 212 of the Framework.

I therefore find that the development does not preserve or enhance the character or appearance of the conservation area. It conflicts with part A. d) of Policy CDH08 of the Local Plan which provides that, amongst other things, proposals should 2 Residential Design Guidance: Supplementary Planning Document (2016) 3 National Planning Policy Framework have regard to local historic context and character, including the appearance, scale, mass and height of buildings, use of materials, patterns of development and the layout of buildings and spaces, and with part D. of Policy HOU03 of the Local Plan which provides that, amongst other things, proposals will be supported, provided that they do not have an unacceptable impact upon the surrounding character of the area.

The development conflicts with part C. a) of Policy CDH01 of the Local Plan which provides that the Council will expect development proposals to respond sensitively to the distinctive local character and design, building form, patterns of development, scale, massing, roof form and height of the existing context.

The development conflicts with part D 11) of Policy D3 of the London Plan (published 2021) which provides that, amongst other things, development proposals should respond to the existing character of a place by identifying the special and valued features and characteristics that are unique to the locality and respect, enhance and utilise the heritage assets and architectural features that contribute towards the local character, and with part C of Policy HC1 of the London Plan which provides that, amongst other things, development proposals affecting heritage assets, and their settings, should conserve their significance, by being sympathetic to the assets’ significance and appreciation within their surroundings.

Policy CDH04 of the Local Plan relates to tall buildings, and therefore is not directly relevant to this main issue. Nevertheless, the above-mentioned policies are sufficient for me to come to a view on this main issue.

The development has enlarged the accommodation available at No 64. As the benefits in this regard are largely private in nature, they attract little weight in support of the development.

The development causes harm to the significance of the conservation area, in conflict with the development plan. Given the great weight given to the conservation of this designated heritage asset, which is an irreplaceable resource, the benefits of the development do not outweigh the harm identified. The relevant material considerations do not indicate that the appeal should be decided otherwise than in accordance with the development plan.

For the reasons given above, having considered the development plan as a whole, the approach in the Framework, and all other relevant material considerations, I conclude that the appeal should be dismissed.