Appeal 3310729

The appeal is allowed. Planning permission is granted for conversion of existing roof into habitable space with the addition of a mansard extension and associated internal amendments at [address], Islington, London [postcode] in accordance with the terms of the application Ref P2022/2887/FUL dated 4 August 2022 subject to the following conditions:

The development hereby permitted shall be begun before the expiration of three years from the date of this decision.

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 in accordance with the following approved plans: PLN 01, PLN 02, PLN 03, PLN 04, PLN 05, PLN 06, PLN 07, PLN 08, PLN 09, PLN 10, PLN 11, PLN 12 & PLN 13.

The main issue is the effect of the proposal on the character and appearance of the Barnsbury Conservation Area (the Conservation Area).

This part of the Conservation Area is comprised of well-established residential terraces of attractive appearance. The form, scale, materials and detailing of these buildings are defining features of its character and appearance.

The host building sits within one such terrace and makes a positive contribution to the character and appearance of the Conservation Area. The proposal would see significant alteration to the property at roof level through the addition of the mansard roof extension.

However, by reason of its set back from the front parapet wall which would be retained, the extension would only have limited public visibility from the main public views towards the building to the front on [address].

There are roof extensions elsewhere in the same terrace at No.s 3, 9 and [address] (No.29), whilst a roof extension spanning No.s 17 and [address] appeared to be under construction at the time of my site visit. This represents a good spread of properties throughout the terrace.

Whilst the proposal would result in the loss of the rear ‘v’ shaped roof parapet, this did not seem to be a common feature to the rear of the existing terrace where many of the properties further along do not incorporate such a feature to the rear.

As such, regardless of when they were constructed, given the presence of other roof extensions, and differing rear roof designs, the architectural unity of the terrace at roof level is limited. I also note the differing design of No. 29, but this does not change my view.

The proposals would not therefore detract from the appearance of the terrace nor from the heritage significance of the Conservation Area which lies in part with the form, scale, materials and detailing of the buildings. The proposal would preserve the character and appearance of the Conservation Area.

There would subsequently be no conflict with policies D4 and HC1 of the London Plan (2021), policies CS8 and CS9 of [name] (2011) and policies DM2.1 and DM2.3 of Islington’s Local Plan: Development Management Policies (2013) which amongst other things require good design that protects heritage assets.

I have not identified any conflict with SPD1 guidance with regard to roof extensions. The property is not identified on a list of those that may be suitable for roof extension under the Conservation Area Design Guidelines2. However, given the current situation at the terrace and resultant lack of harm arising from the proposals I afford this conflict very limited weight.

Planning permission is granted subject to the standard three-year time limit. A condition requiring matching materials is necessary in the interests of the character and appearance of the area. It is necessary that the development be carried out in accordance with the approved plans for the avoidance of doubt and in the interests of certainty.

There is nothing to indicate that the decision should me made otherwise than in accordance with the development plan and I therefore conclude that the appeal should be allowed.