Appeal 3338451

The appeal is dismissed.

Subsequent to the decision made by the Council on the application to which this appeal relates, on 19 December 2023 the Government published the revised National Planning Policy Framework (2023) (the Framework). I consider that there have been no major changes relevant to the main issue in this appeal. It will therefore not prejudice any party by making my decision with regard to the revised Framework.

An application for the erection of mansard roof extension with rear roof terrace; erection of a part one part two storey rear, and alterations to the front and rear fenestration was allowed in 2021. Condition 3 of this permission required that the development granted approval should only be carried out in accordance with the approved plans which were considered in determining the application.

The appellant is seeking to vary this condition regarding revised design plans. These involve the construction of 2 dormer windows with timber framed sash windows as a replacement of the approved ‘Velux’ type flush roof windows, and partial demolition and infill of the masonry rear parapet wall. It is submitted that the changes are due to changes in internal layout of the approved extension.

The main issue in this appeal is the effect that varying the condition would have on the character and appearance of the host property and that of the surrounding area with reference to the [address] Conservation Area (the CA).

From my site visit the development that is the subject of this appeal appears to be under construction and to have been substantially completed. This includes the construction of 2 dormer windows with timber framed sash windows as a replacement of the approved ‘Velux’ type flush roof windows.

The appeal dwelling is a three storey mid terrace property. It is in an area made up of similar terraced properties and falls within a character area of the CA recognised for its long terraces of mid-19th Century houses on wide streets, with front lightwells to a basement area set behind railings. These cohesive architectural and spatial characteristics are exemplified by the appeal dwelling. As such it makes a significant contribution to the significance of the CA.

The CA is a heritage asset to which I have a statutory duty under section 72 of the Planning (Listed Buildings and Conservation Areas) Act 1990. I must pay special attention to the desirability of preserving or enhancing the character or appearance of a Conservation Area.

From my site visit it is evident that there are a substantial number of dormer windows to the front roof slopes of similar properties within the CA. These vary in design and positioning on the mansard roofs to which they relate, however all appear to be relatively modest in scale and to be set down from the top of the front roof slope and set in from the front parapet.

However, the dormer windows on the appeal dwelling to which this appeal relates align with the top ridge of the front roof slope of the mansard extension. This does not accord with the design advice set out in the [name] (2021) for dormer windows, which recommends that they sit within the roof slope.

Combined with the dormer windows only having a limited set back from the front parapet, their alignment with the top roof ridge results in the dormer windows projecting further forward and appearing as larger and conspicuous additions to the appeal dwelling, and as more evident features on the roof of the terrace, when compared to the existing dormers on similar properties in the terrace.

As a result of the height, scale and forward projection of the dormer windows, they appear as bulky and unduly prominent additions to the appeal dwelling. This is evident in street views and results in the appeal dwelling appearing incongruous in relation to the other houses in the terrace and to not reflect the design of dormers in the wider local area. The proposed changes to the rear parapet appear as minor and would not result in any significant detrimental effect on the character or appearance of the appeal dwelling, that of the local area, or to the significance of the CA.

For these reasons I find that the variation of the Condition 3 as proposed as a whole would maintain the, as built, the dormer windows to the mansard extension, which are harmful to the character and appearance of the host dwelling and the terrace of which it forms part and fail to preserve or enhance that of the CA. In the context of paragraph 208 of the National Planning Policy Framework (2023) (the Framework), the harm I have identified to the significance of the CA would be less than substantial. This would be contrary to Policies D1and D2 of the Camden Local Plan (2017) Policies D3 and HC1 of the London Plan (2021) and Sections 12 and 16 of the Framework. Collectively these seek to ensure that development is of high architectural and urban design quality, respects local context and character and preserves or enhances the appearance or character of conservation areas.

Whilst the dormer windows reflect the internal changes made to better reflect changes made to the internal layout of the mansard extension; this is not a substantial public benefit. In general, planning decisions should be made in the wider public interest. In this context, the harm I have identified, including the less than substantial harm to the significant of the CA outweighs these benefits. Dismissing the appeal is a proportionate response in this instance.