Appeal 3356806

The appeal is dismissed.

There is one main issue which is the effect of the proposed extension on the character and appearance of the host dwelling and the surrounding area which lies within the Hadley Wood Conservation Area (CA).

The appeal dwelling, which lies within the [name], is one of a pair of large, handsome semi-detached houses situated on [name], a curved street built between 1885 and 1896. It lies in a row of similar dwellings that, from the street, retain a strong sense of uniformity. The original mirroring between the pairs and between non-attached pairs has been altered in a number of cases, especially by front/side extensions above ground floor. There are also at least two different house designs. Nevertheless, the dwellings remain an attractive and cohesive group.

The dwellings are 2.5 storeys high and constructed in a mixture of red and yellow brick with noticeable red tile hanging. The Hadley Wood CA Character Appraisal states that the dwellings on [name] are characterised by high pitched roofs with hipped ends, complex rooflines with multiple gables and tall chimneys. They have centralised massing with lower, and in the case of the appeal dwelling and others of the same design, narrower side wings flanking a tall, wider central wing. The street, which is spacious and verdant with noticeable gaps between dwellings through which more trees can be seen, rises gently but the appeal dwelling and its neighbours are built on higher land and noticeably elevated from the street, giving them added prominence.

The National Planning Policy Framework (NPPF), 2024, makes clear that conservation areas are designated heritage assets. When considering the impact of a proposed development on the significance of a designated heritage asset, the NPPF advises that great weight should be given to the asset’s conservation. Significance can be harmed through alteration of the heritage asset or development within its setting. Statutory protection is provided by Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990. This requires that special regard/attention is paid to the desirability of preserving or enhancing the character or appearance of the heritage asset, including its setting. Relevant policies set out in the Council’s Local Plan and in particular Policy DM44 of the Development Management Document (DMD), 2014, accord with the NPPF in respect of heritage assets.

The proposed extension has been re-designed following an earlier refusal and dismissed appeal (APP/Q5300/D/23/3315600) to address some of the issues identified. However, although the proposed extension now has a lower, hipped roof which would be more in keeping with the host dwelling and would enable the rear chimney to be seen, it would be noticeably wider than previously proposed, extending almost as far to the side as the original single storey element on the front corner of the dwelling. This would make it a prominent addition in the street scene, notwithstanding its significant set back from the main façade, exacerbated by the paler brick that would stand out in contrast to the prominent red tile and brick of the main facade. It would also disrupt the cascading scale in terms of height and width from the centre outwards, detracting from the architectural importance of the original, single storey element on the front corner. Finally, it would noticeably close the gap between the appeal dwelling and its non-attached neighbour and disrupt the existing mirroring between these two dwellings.

The appellants state that the design would be minimally different from the existing arrangement and that the additional side projection would be a modest 1.3m. Nevertheless, this would approximately double the width of the existing side projection and so, whilst limited in itself, would have a material effect in terms of scale and balance. It is also suggested that, as the attached pair has been altered, the mirroring between the two has already been disrupted. That is so. However, given the position of the proposed extension, it is its relationship with the non-attached neighbour, which appeared to retain its original form when seen from the street, that would be more noticeable and, owing to the increased width, would have an unbalancing effect, exacerbated by the loss of openness resulting from the partial closing of the gap between the two dwellings.

The appellants also point out that from the street the proposed extension would be screened from in front of the dwelling by a plum tree and that as trees in conservation areas are protected it could not be removed. I saw that the tree does provide this screening. However, the side elevation of the dwelling is clearly visible when approaching from the north-east and this would allow an uninterrupted view of the proposed extension. Moreover, the dwelling would be expected to remain long after the tree had reached the end of its lifespan.

Overall, the proposed extension would have an unsatisfactory relationship with the existing dwelling and with its non-attached neighbour that would be harmful to its character and appearance and would fail to preserve or enhance the character or appearance of the CA. In consequence, the significance of the heritage asset would be diminished.

Nevertheless, the harm that would arise to the CA would be less than substantial within the meaning of Paragraph 214 of the NPPF. The harm must therefore be weighed against the public benefits of the proposed development. However, these would be limited, being restricted to the retention of internal layout and features as identified by the appellants, and the small economic benefit of construction.

Overall, I therefore find that although there would be private benefits, as identified by the appellants, the public benefits would be minor. In consequence, they would not outweigh the great weight that should, in accordance with the NPPF, be given to the conservation of the CA as a designated heritage asset. The development would therefore conflict with the NPPF, 2024.

It is concluded on the main issue that the proposed extension would have a materially detrimental effect on the character and appearance of the host dwelling and the surrounding area and that the character or appearance of the [name] would fail to be preserved. In consequence, the proposed extension would, in the context of strategic policies set out in the London Plan, 2021, conflict with Policy CP30 of The Enfield Plan Core Strategy 2010-2025 (adopted 2010) [name] DMD13, DMD14, DMD37 and DMD44 and [name]-1 and HW-12 of the Hadley Wood Neighbourhood Plan (2023). Taken together and amongst other things these expect new developments, and in particular side and roof extensions, to be of a high quality, having regard to their context, be of an appropriate scale, design and detailing and to conserve and enhance the special interest, significance or setting of a heritage asset.

For the reasons set out above and having regard to all other matters raised, including a third party representation supporting the proposed development, I conclude that the appeal should be dismissed.