Appeal 3368620

The appeal is dismissed.

The main issue is the effect on the character and appearance of the [site address] Conservation Area (CA).

The appeal site comprises one half of a semi-detached pair of dwellings located within a residential area to the south of the town centre. It occupies a prominent location at the southern end of [address] at its junction with [address]. The surrounding properties are predominantly similar semi-detached pairs with red brick elevations and hipped roofs finished in clay tile roofs, typical of the local area. Whilst there are examples of detached and terraced properties nearby they are generally of similar design and external appearance.

The Council’s [site address] Conservation Area Appraisal (2007) (CAA) shows that the appeal site lies within an area that was part of the original master plan for the town being located between the southern ends of The Parkway and [address], the main approaches to the town centre. The provision of generous open spaces are at the heart of the character of the conservation area, with the residential areas generally displaying a suburban character with grassed and planted road verges, front gardens enclosed with hedges to provide a park-like environment and a consistency of building forms and layout. [address] is typical of these characteristics with its predominant uniform pairs of semi-detached houses. The appeal site also reflects these characteristics and in particular, due to its corner plot location provides generous open spaces to both street scenes which contribute to the open and verdant setting of the area.

The proposed side extension would be around two thirds of the width of the host dwelling and set back only a small amount from the front elevation. Whilst it would have a lower ridge height and would be of matching materials, it would be seen as an unduly large addition to the relatively modest host dwelling and as a result would unbalance the current symmetrical appearance with the attached dwelling. Overall, it would fail to be sufficiently subservient to the host dwelling and it would appear as an unduly large and unsympathetic addition, exacerbated by its prominent corner location.

The single storey rear addition which would extend the width of the existing house and the proposed side extension, would not be prominently seen in public views, though its mono-pitch roof would likely be visible. Whilst in terms of its size it would not be unduly large, this roof form is not characteristic of the area where such additions are generally flat roofed, often set behind parapets, thus providing a suitable and respectful contrast to the main dwelling.

The proposed dormer would be set within the rear roofslope of the existing dwelling, but nevertheless would be visible within the [address] street scene. Whilst of pitched roof design, it would be a large addition, wider than the first-floor window below it and would occupy the majority of the roof depth, with the same ridge height as the main roof. Overall, I consider that it would appear as an overly large addition that would not be sufficiently subservient to the roof and would fail to complement the style and appearance of the existing dwelling. In addition, such roof dormers do not appear to be characteristic of either street scene and as such it would introduce an incongruous roof form.

The proposed rooflights within the two-storey extension would also be incongruous features given that they are also not characteristic of the area and their siting would further unbalance the appearance of the semi-detached pair. The new front door within the elevation facing [address] would be of somewhat different appearance from that at No. 4, in particular omitting the flat roofed canopy, but given that there are other similar designs within the street it would not be so different as to be harmful.

Overall, however, the proposal would result in additions and alterations that would detract from the pleasant character and appearance of the host dwelling, the relatively uniform character of the wider area and the positive contribution that it makes to the conservation area. I therefore find that it would result in less than substantial harm to the character and appearance of the CA. In accordance with paragraph 212 of the National Planning Policy Framework (the Framework) great weight should be given to the asset’s conservation and in accordance with paragraph 213 any harm should require clear and convincing justification.

The Framework also states at paragraph 215 that in the above circumstances, the harm should be weighed against the public benefits of the proposal, including where appropriate, securing its optimum viable use. I note that the proposal would enhance the sustainability of the dwelling, in particular its energy efficiency, use of water, internal air quality, durability and that this would have associated health benefits for its occupants. However, whilst these benefits are acknowledged, given that such improvements are likely to associated with any proposed extensions, only moderate weight is given to these factors and they do not outweigh the harm to the conservation area that I have found above.

I therefore find that the proposal would fail to preserve the character and appearance of the CA and would thus conflict with Policies SP1, SP9, SADM15 and SP15 of the Welwyn Hatfield Local Plan (2023) which, amongst other things, seek sustainable development, that ensures that the character and appearance of [site address] ’s historical significance and unique heritage are respected, that features important to its character are retained, that any less than substantial harm found is weighed against the public benefits of the proposal and that proposals deliver a high quality design that relates well to its surroundings and local distinctiveness. It would also fail to satisfy the principles of the Council’s Supplementary Design Guidance which seek to ensure that residential extensions are complementary to and reflect the design and character of the dwelling and are subordinate in scale, and, in respect of dormers, that they are contained within and subservient to the roofslope and in proportion with the existing fenestration.

Furthermore, it would fail to comply with Framework which in addition to ensuring that development conserves and enhances the historic environment, seeks to achieve well designed places and developments that function well, add to the overall quality of the area, and are visually attractive and sympathetic to local character, including the surrounding built environment.

I have had regard to the duty under Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 and on the basis of the above, find that the character and appearance of the CA would not be preserved.

The appellant has referred to the potential for the dwelling to be extended under permitted development rights (PDR). It would appear that the dwelling would benefit from these, albeit subject to the limitations that apply to conservation areas. Whilst the absence of a lawful development certificate is not determinative, the proposed two storey extension due to its forward siting relative to the highway of [address], would not appear to comply with the relevant limitations. The appellant cites relevant case law1 in this regard, noting its findings that for a fallback to be a real prospect, a possibility will suffice. [name] acknowledge that it would appear that some limited PDR may apply and some weight can be given to this fallback position as a material consideration, overall it is insufficient to outweigh the considerable harms and related policy conflicts arising.

The appellant has referred to extensions which have taken place at other properties in [address], in particular single storey PDR extensions that are considered to have resulted in a terracing effect. I saw at the time of my site visit that there are a number of such extensions, but these are within a continuous row of buildings which occupy a different position within the street scene. As such they are not comparable to the appeal proposal before me.

I therefore conclude that this appeal should be dismissed.