Appeal 3302700

The appeal is dismissed.

The description of development in the heading above has been taken from the planning application form. Although the decision notice for the application uses a different description, in [name] of the appeal form it is stated that the description of development has not changed. Accordingly, I have used the one given on the original application.

The main issue in this case is the effect of the proposed development on the character and appearance of the existing dwelling and of the [address] Conservation Area.

The appeal property is located in the [address] Conservation Area, which incorporates a significant part of the [address] estate in north Wembley. The estate was designed and built in the late 1920s and early 1930s, by Comben and Wakeling, and is a particularly fine example of inter-war, suburban residential development. Section 72(1) of the Planning(Listed Buildings and Conservation Areas) Act 1990 requires that in the exercise of planning powers in conservation areas, ‘special attention shall be paid to the desirability of preserving or enhancing the character or appearance of that area’.

The character and appearance of the [address] Conservation Area, and, therefore, it’s significance as a designated heritage asset, is derived from its spacious, [name] style layout, and the architectural composition of its dwellings. A key feature of the layout is the generous proportion of green space to buildings, with houses set back from tree-lined streets and long gardens to the rear. In terms of architectural composition, the streets follow a consistent pattern, with dwellings arranged in semi-detached or linked detached pairs, using standardised plan forms, but designed and detailed externally in a variety of Tudor revival and Arts and Crafts styles, which creates an impression of individually designed houses.

The properties in [address] exemplify this character and appearance, and thereby contribute to the heritage significance of the Conservation Area. The appeal property forms one of a pair of white rendered, semi-detached houses with [address], designed in the characteristic architectural style of the estate, set back from the street and with long rear gardens. Whilst both houses have been extended at the side and rear, the additions are subordinate, respecting the dimensions and architectural composition of the original dwellings, and preserving their garden settings.

[address] Conservation Area Design Guide, adopted in 2015, provides guidance on how properties in the Conservation Area can be extended so as to preserve or enhance the character and appearance of the area. It explains that rear extensions can have a serious impact on the character of the Conservation Area, and that a large extension is likely to harm the garden setting of a dwelling. To this end, section 3.2 of the [name] stipulates that, for a semi-detached house, the maximum depth for a single storey rear extension is 3 metres (m) from the original rear elevation.

The appeal property has an existing rear extension of around 3.2 m in depth. The proposed conservatory would add a further 3 m, resulting in a single storey rear extension of more than 6 m in depth from the rear elevation of the original dwelling, significantly in excess of the maximum advisory depth specified in the [name]. It would create a rear projection of disproportionate size in comparison to the carefully composed dimensions and architecture of the original dwelling, and its semi-detached neighbour at no. 54. The excessive depth of the resulting extension would also diminish the proportion of garden space to building, which is an important feature in the layout of the estate.

Although the proposed conservatory would be at the rear, it would nevertheless be visible from the vantage points of adjoining and surrounding properties, which comprise views within the Conservation Area. As such the appeal proposal would cause harm to the character and appearance of the Conservation Area, and thereby its significance as a designated heritage asset.

In this case, because the proposed conservatory would be at the rear and thereby less prominent, the harm would be less than substantial. Where this is the case, paragraph 202 of the National Planning Policy Framework (the Framework) requires the harm should be weighed against the public benefits of the proposal. Paragraph 199 of the Framework establishes that when considering the impact of a proposed development on the significance of a designated heritage asset, great weight should be given to the asset’s conservation, irrespective of the degree of harm to its significance. Paragraph 200 of the Framework also expects that any harm to the significance of a designated heritage asset should require clear and convincing justification.

I recognise that the proposed conservatory would provide additional living space to the appellant, albeit this would be a private rather than a public benefit, which carries little weight in the heritage balance. I have also taken account of the other justifications offered by the appellant, including that the conservatory would be more modest than the previous extensions which have been refused, and that it has been designed to replicate garden rooms associated with good quality housing of the 1920s and 1930s. However, given the great weight to be accorded to the conservation of the heritage asset, I find that the benefits and justifications offered by the appellant would not outweigh the harm to the significance of the heritage asset identified above.

On this basis, I conclude that the proposed development would fail to preserve or enhance the character and appearance of the [address] Conservation Area. Consequently, it would be contrary to the expectations of the Act and to Policy BHC1 of the Brent Local Plan 2019-2041, which seeks to avoid harm to Brent’s heritage assets. It would also conflict with paragraphs 200 and 202 of the Framework.

The side walls to the proposed conservatory would rise above the existing boundary wall and fences between the appeal property and nos. 54 and [address] for a distance of 3 m from the rear of the existing extensions. However, the additional height on the boundary would not be overbearing on the outlook from the ground floor rooms at the rear of the neighbouring dwellings, nor cause an unacceptable loss of light given the southward facing aspect of the properties. Although the lantern style roof to the proposed conservatory may shed some light upwards, there is little evidence to suggest this would cause any significant glare into the upper floor windows of the neighbouring properties.

As such I find that the proposal would not cause an unacceptable degree of harm to the living conditions of the occupiers of nos. 54 and [address], in terms of outlook and lighting. However, this does not reduce the heritage harm which I have found.

For the reasons given above, and taking account of all other matters raised, I conclude that the appeal should be dismissed.