Appeal 3329617

The appeal is allowed and planning permission is granted for demolition of existing single storey conservatory to be replaced with a single storey rear extension. New roof including 2 no. rear facing dormer windows at [site address] in accordance with the terms of the application Ref 23/2352/HSE, dated 25 May 2023, subject to the following conditions:

The development hereby permitted shall begin not later than 3 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:19TC-101 Existing ground floor, 19TC- 102 Proposed ground floor, 19TC-103 Existing first floor, 19TC-104 Proposed first floor, 19TC-105 Proposed loft, 19TC-106 Existing roof, 19TC-107 Proposed roof, 19TC-108 Existing and proposed front elevation, 19TC-109 Existing and proposed side elevation, 19TC-110 Existing and proposed rear elevation, 19TC-111 Existing and proposed side elevation, 19TC-[address], 19TC-[address] and 19TC-100 Location plan.

The roof of the extension hereby permitted shall at no time be converted to or used as a balcony, roof garden or similar amenity or sitting out area.

The main issues in this appeal are the effect of the appeal proposals on the appeal property and whether they would preserve or enhance the character or appearance of the [address] Conservation Area (CA).

The appeal property (No 19a) stands at the end of The Croft, within the CA. It is also subject to an Article 4 Direction which has removed permitted development rights. The adjacent property, No 19 is locally listed. Due to the distance between Nos 19 and 19a, the proposed works would have no impact on the locally listed building or its setting.

[address] Conservation Area Character Appraisal Statement (2007) (the Appraisal) identifies 5 [name] within the CA, each with discrete qualities. Of relevance to this appeal, the CA has a medieval and later street pattern, with cohesive street frontages and attractive open and closed spaces. There are many trees and other landscape features. Together they provide a high-quality environment within which a number of individual buildings make a special contribution. The CA’s green spaces range from private front gardens to formal parks which are generally defined by informal hedges with trees or low-level walls. Open spaces and constrained narrow alleys leading off the [address] reflect the boundaries and general form of medieval burgage plots. Narrower and more intimate side streets, including The Croft, lead off [address]. The combination of these street patterns and spaces are essential to the character of the CA.

The part of the CA around the appeal site is residential in character, comprising mainly semi-detached and detached properties of varying architectural forms, scales and designs which are laid out in a random pattern within well-landscaped gardens, many with brick boundary walls. The appeal plot rises from the road and No 19a fronts onto the narrower, alley, part of the Croft, close to the point where it opens into a wider road. The house is set well back from the road behind a tall boundary wall with entrance gates.

The existing conservatory is of little design merit and does not reflect the architecture of No 19a. The Council’s evidence that the conservatory appears ‘lighter’ than the proposed extension is unconvincing, given its bulkiness and far from slender glazing bars. There is no reference to the importance or otherwise of conservatories in the Appraisal. Its removal would preserve the character and appearance of the CA.

The proposed replacement extension would match the materials, windows design and style of the original house and its existing extensions. It would be lower than the conservatory, would not be as deep and would appear subordinate to the main house. The extension would comply with the Council’s Residential Design Guidance SPD (SPD) which states, in summary, that extensions should be subordinate and consistent with the form, scale and architectural style of the original building by respecting its proportions and using an appropriate roof form. The extension would also comply with the SPD’s numerical standards.

I conclude that the proposed extension would complement the appearance of the host property and would preserve the character and appearance of the CA. Furthermore, the cumulative effect of the proposed single-storey extension combined with the existing side extensions would not overwhelm the character of the original dwelling as the Council suggests.

To provide accommodation in the roof, the ridge of the host dwelling would be raised by 0.5m. A crown roof, steeper roof pitches to all sides and a top rooflight would be incorporated. I am satisfied by the evidence that the proposed raised roof would not appear ‘top heavy’ or more dominant. Whilst its appearance would change, the resulting roof would be in keeping with the architectural style of No 19a which is an individually designed building.

The appeal evidence indicates that Nos 21 and 23 The Croft have crown roofs. Whilst they are outside the CA, they are visible from the appeal site and can be considered as part of the context of the appeal site. In addition, No [address] which is a converted, locally listed Edwardian building close to the appeal property has a sizeable crown roof. It is similarly located within the [address] Conservation Area and is also in the North Barnet Area of Special Character. Further examples of crown roofs in [address] and in [address] have also been identified. Whilst each case should be determined on its own merits, these examples demonstrate that crown roofs are not alien to the area around the appeal site, including within the conservation area.

Having regard to the unique design of No 19a and its context, I conclude that the proposed increase in height and change in roof pitch would be acceptable and would preserve the character and appearance of the CA.

The proposed dormer windows would comply with the detailed guidance of the SPD which states that they should be subordinate features and be set well within the roof slope. I agree with the Council that this element of the proposal would be acceptable.

For the reasons set out above and having regard to all other matters raised, I conclude that there would be no conflict with the requirement for high quality design set out in Policy DM01 of the LB Barnet Development Management Polices DPD (2012) ([name]). Furthermore, the proposal would preserve the character and appearance, or significance, of the CA in accordance with DMP DPD Policy DM06. The similar requirements of Policies D3 and HC1 of the London Plan (2021) and the SPD would also be met.

Accordingly, the appeal is allowed subject to conditions.

A condition is necessary requiring the use of matching materials to protect the appearance of the host property and to preserve the character and appearance of the surrounding CA. I have included a condition identifying the approved drawings for the avoidance of doubt and in the interests of proper planning. A condition prevents the use of the flat roof of the extension as a balcony or other sitting out area to ensure that there is no overlooking which could harm the living conditions of the occupiers of neighbouring properties.