Appeal 3304994

The appeal is dismissed.

The description of development is taken from the decision notice and appeal form. In my view this more clearly and accurately describes the development and I have used it for my decision.

The appeal proposal comprises several elements however the Council’s concerns are with the side extension. They also advise that planning permission has been granted for the various other elements under Council reference 2021/3417. I have therefore restricted my considerations to the disputed element.

The main issue is the effect of the development on the character and appearance of the host property and the surrounding area, including the Three Sisters Conservation Area.

No.23 is a semi-detached property which along with similar properties in the neighbouring streets forms the Three Sisters Conservation Area (TSCA). As such, I have a statutory duty under section 72(1) of the Act to pay special attention to the desirability of preserving or enhancing the character or appearance of that area.

From my site visit and the information before me the appearance and the significance of the TSCA is defined by the homogeneity of properties, which are primarily semi-detached with hipped roofs and the associated space between creating a subdivision and defining rhythm.

Currently the gap between the appeal property and the adjoining pair (Nos. 25 & 27) is linked at ground floor via a wall which allows for views above which includes the full flank elevations and glimpses of other properties beyond. The other half of the semi (No.21) is connected to its neighbours via an infill which fully encompasses that gap, but otherwise the space between the semi-detached properties along the east of [address] and in the surrounding streets is generally retained. In contrast more extensive infill extensions have occurred to the other side of [address] resulting in the lengths of continuous built form.

The addition of side extensions and the resultant terracing effect is identified as a negative element in the Three Sisters Conservation Area Appraisal & [name] 2009 (CAAMS). The CAAMS specifically indicating a resistance to two-storey side extensions and that only single storey extensions set back from the front façade will be allowed. I accept there is no policy in the Wandsworth Development Management Policies Document (DMPD) which specifically prevents two storey side extensions, and as highlighted by the appellant the Council’s Housing SPD 2016 (SPD) indicates that they may be acceptable. Nonetheless, both the SPD and DMPD policy DMH5 echoes the concerns in the CAAMS and resists two storey extensions which cause a terracing effect by infilling spaces between semi-detached buildings.

From my site visit it would appear that the majority of the existing infills have been in place for a while and generally occur to either both adjoining properties or halves of the semi. Other than [address], referred to by the appellant, there is no information before me to indicate that any two storey extensions have been permitted post the introduction of the CAAMS or the SPD. In allowing the appeal for the extension to [address] the decision explains that matters of relevance in that case were an existing identical extension to the other half of the semi and a larger gap to the neighbour. Neither of which apply to the appeal site.

The first-floor element of the proposed extension is designed with a more extensive set back. Overall, the extension would have a subservience to the host property, however, the stepped form is somewhat at odds with the existing property and would still extend up to the shared boundary. The only physical gap would be on the neighbour’s property and if the extension were to be replicated the gap would be entirely closed. [name] acknowledge that the stepped form of the extension would limit its visual prominence the reduced width of the gap would still significantly dimmish the spaciousness and visual separation to the detriment of the rhythm and historic pattern of development.

The proposal would alter a small part of the TSCA, nonetheless the space between the buildings is an important characteristic and the cumulative effect of such changes can diminish its quality. Having regard to the National Planning Policy Framework the harm to the conservation area would be less than substantial. Nevertheless, this is still a matter of considerable importance and weight and there are no identified public benefits of the proposal which would outweigh the harm.

I therefore conclude that the proposal would fail to preserve the character and appearance of the TSCA and would be contrary to policy IS3 of the [name], DMPD policies DMS1 and DMH5, and policy HC1 of the London Plan which amongst other things require development to contribute positively to local spatial character, and that extensions and alterations do not harm the host building or street scene, as well as the advice in the SPD. It would also be contrary to policy DMS2 of the DMPD and the CAAMS regarding proposals affecting heritage assets and would fail to satisfy the requirements of section 72 (1) of the Planning (Listed Buildings and Conservation Areas) Act 1990.

For the reasons set out and having regard to all other matters raised the appeal is dismissed.