Appeal 6004467

The appeal is allowed and planning permission is granted for the erection of a loft conversion including rear dormer roof extension and outrigger extension at [site address] , Richmond upon Thames, [postcode] in accordance with the terms of the application, Ref PA25/4132, subject to the following conditions:

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 approved plans: [name](01)00 [name], EX(01)01 [name], EX(01)02 [name], EX(03)01 [name], EX(03)02 [name], PL(01)01 [name], PL(01)02 [name], PL(03)01 [name] and PL(03)02 [name].

The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building.

The development hereby permitted shall be carried out and thereafter maintained in accordance with the [name] dated November 2025.

An application for costs was made by [name] against the Council of the London Borough of Richmond upon Thames. This is the subject of a separate

The main issue is the effects of the proposal upon the character and appearance of the appeal property and wider area.

The appeal relates to a mid-terraced, two-storey dwelling with a rear outrigger within a residential neighbourhood comprising properties of similar type and age. The proposal is for a loft conversion that would involve the erection of an ‘L-shaped’ dormer extension across the original rear roof slope and over the outrigger with two roof lights to the front elevation.

[address] Extensions and External Alterations Supplementary Planning Document (SPD) was adopted in May 2015. In relation to roof extensions, it advises that, amongst other things, they should be ‘in-scale’ with the existing structure and should not dominate the existing roof, and that dormers should have windows smaller than that of windows to the floor below.

During my visit, I observed that ‘L-shaped’ dormer window extensions were not uncommon to the rear elevations of other properties along this side of [address]. Between them these were of varying sizes and forms and included a variety of window openings in terms of sizes and positions. Moreover, the Council has confirmed that a Certificate of [name] or Development (LDC) was previously issued for works at the appeal property described as ‘Loft conversion including rear dormer roof extension and outrigger extension’ (Ref PA25/2945). The difference between the works that have been accepted as permitted development and the appeal proposal amount solely to the position and shape of the window proposed to be installed upon the rear face of the extension over the outrigger.

Whilst the proposed roof extension would undeniably dominate the existing roofscape and dwelling as a whole, in conflict with the SPD’s guidance, the appellant has a legitimate fallback position with a very realistic prospect of implementation whereby a similar roof extension in terms of size and position could be constructed. This is a material consideration to which I attach significant weight.

With this in mind, and having regard also to the innumerable roof extensions in the vicinity, which have resulted in a markedly evolved roofscape to the rear elevations of the terraces along [address], I am not persuaded that the siting, scale or bulk of the proposal would appear harmful to the character or appearance of the dwelling or incongruous within the context of its rear garden setting.

The proposed triangular window to the rear elevation and set within the side cheek of the extension over the outrigger would be unquestionably larger than the windows to the property’s fenestration pattern below, and of different style. In this regard there would be some further conflict with guidance contained within the SPD. However, by following the profile of the dormer’s cheek and reflecting the shape and proportions of the façade within which it would be inserted, the window would represent a well-considered contemporary approach that in my judgement would be neither incongruous nor harmful within a context where the glazing patterns at an elevated level to the rear of properties in the vicinity have evolved with little consistency or cohesion.

Overall, notwithstanding any conflict with the SPD, I am satisfied that there would be no harm to the character or appearance of No 24 or the wider area. As such, there would be no conflict with Policy 28 of the Richmond upon Thames Local Plan (2024 to 2039), adopted in 2025, as far as it seeks to ensure development is compatible with local character. For the same reasons there would be no conflict with the National Planning Policy Framework’s policy requirements for achieving well-designed places.

In addition to the standard time limit condition, a condition requiring the development to be carried out in accordance with the approved plans is necessary for the avoidance of doubt and in the interests of proper planning. A further condition is necessary to ensure that the development is carried out in materials to match the existing in order to safeguard the character and appearance of the area. I have also included the Council’s further suggested condition requiring the development to be carried out and maintained in accordance with the submitted [name] in the interests of safety.

For the reasons given above, the appeal is allowed.