Appeal 3370168

The appeal is allowed and planning permission is granted for a first floor rear extension at [site address] , Hertfordshire, [postcode] in accordance with the terms of the application, Ref 25/0644/HSE, and the plans ref. Location Plan and Plan 001: Pre-existing, Existing and [name], submitted with it.

There is one main issue which is the effect of the proposed first floor rear extension on the character and appearance of the host dwelling, the semi-detached pair and the surrounding area, including the street scene of [address].

The appeal site comprises a semi-detached house on a spacious plot. The dwelling has been rendered and painted and thus stands out as different from the majority of similar dwellings in the street which retain the original brick finish. The dwelling has been extended to the rear with a deep, single storey, flat roofed rear addition across the full width and a rear box dormer which occupies most of the width of the roof. These alter the appearance of the rear of the dwelling and, in particular, introduce prominent flat roofs. Both extensions have been confirmed to be lawful.

A first floor rear extension with a flat roof has also been constructed across the full width of the dwelling to a depth of some 1.5m. This is the subject of the appeal.

Although occupying the full width, the limited rearward projection at first floor ensures that the extension appears as a modest addition which sits comfortably between the single storey extension and the roof dormer. The Council points out that the Planning and Design Guide Supplementary Planning Document, [name]: Guidelines for [name] and Alterations (SPD), 2006, suggests that first floor extensions should be no more than half the width of the dwelling, with the rear depth kept to a minimum. However, in this case where the proposed depth of the extension is very limited, I consider that, as there would be no materially detrimental effect on the living conditions of neighbours, a wider extension would be acceptable since it would remain proportionate and secondary to the host dwelling and would not detract from the character or appearance of the semi-detached pair.

The Council suggests that the form of the extension would appear visually incongruous. This appears, from e-mail correspondence with the case officer submitted in evidence by the appellant, to refer not only to the width of the extension but to the flat roof which, it is suggested, should be altered to a profile similar to that of the original dwelling. However, the proposed flat roof would reflect the profile of the existing structures to the rear and ensure that the first floor extension appeared as a harmonious and cohesive element between the single storey extension and the dormer, which now define the roof profile of the rear elevation. I therefore find that in this case a flat roof would be visually acceptable and sympathetic to the character and appearance of the host dwelling.

The Council suggests that the design approach would be at odds with the relatively consistent and legible character of the surrounding housing. I noticed that many dwellings nearby have not been extended to the rear or have modest single storey rear additions and thus the original roof profile is retained. However, both the single storey rear extension and the roof dormer at the appeal dwelling are lawful. The first floor rear extension must therefore be considered in the context of the already altered rear elevation, which I have done, rather than the original arrangement albeit that this is retained on other dwellings. Moreover, other dwellings may be altered in the future, including through flat roofed single storey and roof dormer extensions without the need for planning permission.

The extension would have a negligible effect on the street scene of [address], since it would only be glimpsed at an angle between the appeal dwelling and its non-attached neighbour.

It is concluded on the main issue that the proposed first floor rear extension would have no materially detrimental effect on the character or appearance of the host dwelling, the semi-detached pair or the surrounding area, including the street scene of [address]. In consequence, taken in the context of strategic polices SP1, SP2 and CS22 set out in the Hertsmere Local Plan Core Strategy, adopted 2013, it would comply with Policies SADM3 and SADM30 of the Site Allocations and Development Management Policies Plan, 2016.

Taken together and amongst other things, these policies expect new development to complement the local character and be of a high quality design. In order to achieve this, development is expected to respect, enhance or improve the visual amenity of the area by virtue of its scale, mass, bulk, height, and form.

Turning to conditions, since the development has been completed these are not necessary. However, for the avoidance of doubt I will include the references of the approved plans in my decision.

For the reasons set out above and having regard to all other matters raised, I conclude that the appeal should be allowed.