Appeal 3314907

The appeal is allowed and planning permission is granted for a single storey extension to the rear of the property, a full internal refurbishment of the whole property, significant improvements to the environmental performance of the whole thermal envelope which include the replacement of all the windows and external doors, and complete overhaul of all roofs in accordance with the terms of the application Ref 22/4902/HSE, dated 4 October 2022, subject to the following conditions:

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

The development hereby permitted shall be carried out in accordance with the following approved plans: A001A, A100A, A101A, A110A, A111A, A112, A113, A201A, A202A, A210, A211, A212, A213 and A600A.

The materials to be used in the construction of the external surfaces of the extension hereby permitted shall match those used in the existing building except as otherwise specified on the application form and approved plans.

Notwithstanding the details shown on the approved plans, the rooflights hereby approved shall be of a ‘conservation’ style (with central, vertical glazing bar), set flush in the roof.

The roof of the ground floor extension hereby permitted shall only be used in connection with the repair and maintenance of the building and shall at no time be converted to or used as a balcony, roof garden or similar amenity or sitting out area.

Notwithstanding the provisions of the Town and Country Planning (General Permitted Development) (England) Order 2015 (or any order revoking and re-enacting that Order with or without modification), no windows or doors other than those expressly authorised by this permission shall be installed at any time in the side elevation of the extension hereby approved, facing 73 [name].

The main issue is the whether the proposal would preserve or enhance the character or appearance of the Monken Hadley Conservation Area (CA).

71 [name] is a detached 2 storey house with a mock-Tudor frontage, located within the CA opposite a triangular green space. The Council’s 2007 Monken Hadley Conservation Area Character [name] (CAS) notes that [name] is lined by cottages and some larger houses, built in a variety of traditional styles and materials. No 71 is not noted as being of particular significance, but it does contribute to the diverse and attractive street scene.

The proposal would extend an existing pitched roof garage/kitchen range further to the rear, with a conjoined, part flat roofed extension at the back of the main house. This follows on from a similar but smaller extension being allowed on appeal in 2019 ([name]/N5090/D/19/3233119).

The only part of the proposed extension that would be seen from the street or other public vantage points would be the roof of the garage/kitchen extension, which would replicate the existing pitched roof form. Views from the rear show that properties on this side of [name] have been extended at the back in various ways, including a number of substantial and/or flat roofed extensions. The proposed extension has been well designed to fit into this context.

The proposal would be small in scale compared to this large house and set into rising ground. Although it would cover most of the house’s back wall, that element of the building does not appear to be of architectural or heritage significance. The small area of flat roof would be partly disguised behind a section of pitched roof. The large glazed areas proposed at the back would be a modern design feature, but would reasonably complement the building by adding a degree of contrast and variation. They would hardly be seen in any case.

I note the concerns of the Conservation Area Advisory Committee, which are similar to those of the Council, but find no harm here. I conclude that the proposal would preserve the character and the appearance of the CA. It would accord with the aims of policy CS5 of Barnet’s Local Plan Core Strategy, policies DM01 and DM06 of Barnet’s Local Plan Development Management Policies, the Residential Design Guidance Supplementary Planning Document and the CAS, to secure high quality design that respects local context and protects heritage assets in line with their significance.

I impose a condition specifying the relevant plans to provide certainty. Conditions requiring the use of matching materials and conservation style rooflights are necessary to protect the character and appearance of the conservation area. Further conditions restricting the use of the new flat roof and preventing the insertion of any additional windows and doors on one side of the extension are needed to protect privacy at neighbouring properties.

For the reasons set out above, and having regard to all other matters raised, I conclude that the appeal should succeed.