Appeal 3354221

The appeal is allowed and planning permission is granted for rear extension at lower ground floor and set back infill extension at ground floor at [site address] , Kensington and Chelsea, London [postcode] in accordance with the terms of the application [name]/24/04630, and the plans submitted with it, subject to the conditions set out in the schedule attached to this decision:

I have taken the description of development from the application form. Although slightly different to that on the decision notice, no confirmation that a change was agreed has been provided.

The appeal site is in a conservation area. I have therefore had regard to section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 (the Act) to pay special attention to the desirability of preserving or enhancing the character or appearance of the Kensington Conservation Area (the CA).

A revised version of the National Planning Policy Framework (the Framework) was published in December 2024 and updated in February 2025. Whilst this made certain revisions to aspects of national planning policy, the provisions in respect of the main issues in this case are largely unchanged, other than paragraph numbering. I am therefore satisfied that there is no requirement to seek further submissions on the revised Framework from the main parties, and that no party would be disadvantaged by determining the appeal accordingly.

The main issues are the effect of the proposal on: • The character and appearance of the host property and whether or not the proposed development would preserve or enhance the character or appearance of the CA; and, • The living conditions of the occupiers of 13 and [address] and 16 and [address], with particular regard to privacy and outlook.

The appeal site, [site address] (No 15), is a three-storey mid terraced townhouse located within the CA. It forms part of a row of similarly designed properties on the west side of [address]. The CA is predominantly residential, although it also includes part of the commercial [address] and [address] Gate. Streets are generally laid out in a tightly grained urban grid form.

The area within which the appeal site sits is in the north-east corner of the CA. This area is largely characterised by narrow streets containing two or three storey 19th Century terraced houses of simple form in a variety of colourful red brick, painted brick or painted stucco external finishes. Although lacking the detailed typology of more grand period properties nearby, the townhouses along [address] are simply and attractively designed with repetitious window arrangements on front elevations. Architecturally, the proportions of door and window openings are all emphasised verticality along the street.

The appellant’s evidence refers to the Kensington Conservation Area Appraisal (2017) (CAC) which notes that [address] includes terraced houses which have a less consistent appearance than other streets in the CA, with different façade designs and range in height from two to three storeys. Nonetheless, the CAC goes on to acknowledge that the variation in design and architectural decorative finishes of the groups of houses adds to the interest of the street and makes a positive contribution to the character of the area.

From the evidence and observations at my site visit, I consider the significance of the CA, insofar as it relates to this appeal, is derived from the intimate street width which is lined with period properties. It is also attributed to the individual groups of terraces that include front boundary railings, parapet roofs, vertically aligned fenestration and a vibrant but coherent palette of external colourwash.

The appeal property is finished in painted brick. Steps lead up to the front door and incorporate black metal railings to each side. This arrangement is similarly replicated in the terraced block from 9 to 25 (odds) within which the appeal property sits. At the rear, the appeal property and its neighbours have more modest elevations, incorporating less architectural detailing of their front façades and incremental alterations and additions of varying designs and sizes. The appeal property incorporates many of the important design elements and historic character which reinforces its architectural integrity and contributes positively to the significance of the CA.

The proposed lower ground floor extension would replace an existing conservatory at the rear of the property which currently fills a gap between an existing three storey rear outrigger and the outrigger of the adjacent property, [address] (No 17). The extension would incorporate a flat roof and span the full width of the property. There would be a modest rearward projection from the existing rear outriggers and bi-fold doors would open out on to a small rear garden.

I note the proposed extension would completely cover the rear elevation of the existing outrigger of No 15 at lower ground floor level. However, it was apparent from my site visit that alterations and extensions to rear elevations are common on surrounding properties and the wider CA. To some extent, while I was unable to see the rear elevations of all properties along [address] at my site visit, the original rhythm along the rear elevations that I did see, as well as those on [address] opposite, has been diminished by the varied additions and alterations to individual properties.

Due to its modest scale and design, which would not project significantly above the rear or the side boundaries, the proposed lower ground floor extension would not appear as a disproportionately large or insensitive addition to the rear elevation. Neither would it unacceptably unbalance the appearance or form of the host property.

It is also proposed to erect a ground floor rear extension above part of the proposed lower ground floor addition referred to above, which would replace an existing flat roof terrace. This extension would sit between the existing outriggers at No 15 and No 17 and include French doors and a Juliet balcony with black railings to match those already on the terrace. The proposed extension would be visible in views taken from the rear windows and gardens of properties on [address] and in glimpses from the gardens of adjoining properties. Given the slight set back from the rear elevation of the outriggers, flat roof design and construction in materials that would match the host property, the proposal would not be overly prominent.

Although the proposed ground floor level infill between outriggers may be the only one within the immediate vicinity. Nevertheless, I consider it would not be incongruous nor significantly at odds with the vernacular form of the host building. It would be seen in the context of other additions and alterations prevalent in the area. Taking both the proposed lower ground and ground floor extensions together, and that the existing sash window on the first floor rear elevation would be retained, I am satisfied the overall aesthetic value of the host property would be preserved.

Although views from public vantage points within the CA would be limited, conservation areas are experienced from both the public and the private realm. The proposal would be clearly visible from the windows, gardens and roof terraces of surrounding dwellings. Nevertheless, for the above reasons, the proposal would not diminish the appearance of the host building or the significance of the CA. The character and appearance of the CA would be preserved.

Consequently, the proposal would comply with the Act and with CD1, CD2, CD4, CD10, CD13 and CD15 of the Kensington and Chelsea New Local Plan Review (July 2024) (the Local Plan). Collectively these policies, amongst other things, seek a high standard of development, including alterations and extensions, that preserves and enhances the architectural quality, integrity and character of buildings, including historic characteristics and respects its context. Development is also required to preserve or enhance the character or appearance and significance of the conservation area within which it sits.

I observed at my site visit that there are openings on the side elevation of the outrigger of the adjoining property at No 13 facing towards the appeal site. I also saw that the size of the external outdoor amenity space at Nos 13, 15 and 17 is small. However, due to its modest projection and limited height, which would not be significantly higher than the existing side boundaries with No 13 and No 17, the proposed lower ground floor extension would not be overbearing or harm the outlook from the windows or gardens of these neighbouring properties. In addition, as no windows are proposed on the side elevations of the proposed lower ground floor extension and the ground floor extension would be set back from existing outriggers, there would be no opportunity for overlooking to occur towards No 13 and No 17.

Views are already obtainable between some rear facing windows on [address] and [address]. Given there is an existing conservatory at No 15 and a high wall along the boundary with properties on [address], intervisibility between No 15 and rear facing windows of properties on [address] would be largely unaffected by its replacement with the proposed lower ground floor extension.

The existing ground floor terrace and first floor rear windows of the host building already provide views towards the rear windows and gardens of properties on [address]. The set-back of the proposed ground floor extension from the outriggers would limit views towards the rear of some properties along [address]. However, I acknowledge that direct views would be obtainable from this extension towards 16 and [address] (Nos 16 and 18).

Nevertheless, with the surrounding area being relatively built-up, some mutual overlooking is not unusual. [name] recognise the proposed ground floor extension includes a Juliet balcony the room would be more likely to be used all year round than the existing outdoor terrace, it would not project beyond the existing outrigger, which already includes windows at ground and first floor level. Consequently, the level of overlooking towards Nos 16 and 18 from the proposed extensions would not be unacceptable.

Accordingly, I conclude that the proposal would not harm the living conditions of occupiers of 13 and [address] and 16 and [address], with particular regard to privacy and outlook. I therefore find no conflict with Policy CD9 of the Local Plan which, amongst other matters, seeks that good living conditions for occupants of neighbouring buildings is provided, including in relation to privacy and outlook.

I note the previous recent appeal on the site that was dismissed1. However, this was for a roof extension. As such, it is not comparable to the proposal before me.

I have carefully considered the concerns of neighbouring residents. The Council does not allege that the proposal would have an adverse effect on living conditions of surrounding residents in relation to light or noise and I agree. Having visited the site and viewed surrounding buildings from the rear of the appeal property, due to the position, scale, design and orientation of the proposed extensions, they would 1 Appeal Ref: APP/K5600/D/24/3346553 not unacceptably affect the amount of sunlight or daylight reaching surrounding properties.

There is no compelling information before me that the proposal would lead to an unacceptable increase in noise. Indeed, because the existing outdoor terrace and conservatory would be replaced by extensions of more solid construction, it is likely that noise would be reduced overall as a result.

The decision would not set a precedent for the area, as each proposal must be assessed on its own merits and the particular circumstances of the site.

I have considered the suggested conditions from the Council and had regard to Paragraph 57 of the Framework and the National Planning Practice Guidance in terms of the use of planning conditions. I have undertaken some minor editing and rationalisation of the conditions proposed by the Council in the interests of precision and clarity.

In addition to the standard time limit condition, a condition specifying that the development is carried out in accordance with the approved plans is necessary in the interests of certainty. In order to protect the character and appearance of the host building and the conservation area conditions requiring matching materials, including door and Juliet balcony specifications, are reasonable and necessary.

A condition to prevent use of the roof of the extensions as outdoor terraces is necessary to protect the living conditions of neighbouring residents.

A pre-commencement condition requiring a Site Construction Management Plan to be submitted is reasonable in order to minimise disruption to adjoining occupiers at an early stage and to ensure details are available to contractors before work commences. The appellant has not objected to the inclusion of this pre-commencement condition.

For the reasons given above, and having regard to all other matters raised, I conclude that the appeal is allowed and planning permission is granted.

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the following approved plans: Site Location Plan 275A-EX-010-01; Site Block Plan 275A-EX-011-01; Proposed Lower Ground Floor Plan 275A-10-099-01; Proposed Ground Floor Plan 275A-10-100-01; Proposed First Floor Plan 275A-10-101-02; Proposed Roof Plan 275A-10-103-01; [name] 275A-10-300-01; [name] 275A-10-301-02; Proposed Section AA 275A-10-200-01; Proposed Section CC 275A-10-201-02

The external materials of the development hereby permitted shall match those used in the existing building, including in colour, texture, profile and, in the case of brickwork, face-bond and pointing.

The external doors and frames hereby permitted shall be white painted timber and retained as such thereafter.

The Juliet balcony hereby permitted shall be painted black and retained as such thereafter.

The roofs of the lower and ground floor extensions hereby permitted shall not be used at any time as a terrace or outdoor amenity space.

No development shall commence until: i. An Appendix A Checklist and Site Construction Management Plan (SCMP) for the development have both been submitted to, and approved in writing, by the local planning authority, and then; ii. Copies of the approved Checklist and SCMP, and their written approval, have been submitted to the local planning authority to be placed on the property record. The development shall be carried out in accordance with the [name] and SCMP so approved, or in accordance with a subsequent Checklist or SCMP as may be approved under this condition. END OF CONDITIONS