Appeal 3328347

The appeal is dismissed insofar as it relates to the alterations to the roof to form an end gable, rear dormer and the insertion of one rooflight in the front roofslope. The appeal is allowed and planning permission granted insofar as it relates to the erection of a front porch and single storey rear extension at [site address] [postcode] in accordance with the terms of the application, [name]/1001/23, dated 28 March 2023, and subject to the following

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

The development hereby permitted insofar as the details relate to the front porch and single storey rear extension shall be carried out in accordance with the following approved plans: A01 rev 1; A02; A03 and A04.

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.

Although the Council has not provided the Appeal Questionnaire, there is sufficient information available for the assessment of the proposed development from the policies provided for other appeals being determined at the same time and the documents and drawings posted on the Council’s application portal. For reasons of clarity in drafting this Decision, the description of development is adopted from the Council’s Decision Notice.

It is considered that the main issue is the effect of the proposed development on the character and appearance of the host property and the surrounding area, including the streetscene.

The appeal property is a 2-storey end of terrace dwelling situated within a predominantly residential area of similarly designed terraced and semi-detached dwellings. There are examples of detached dwellings including [address]. The dwellings generally possess hipped roof forms but there are examples of hip to gable roof extensions along [address]. Some of the extended dwellings have dormer extensions, including the visually dominant alteration at the junction of [address] and [address] whereby the scale of the roof extension appears as an additional floor to the property.

The proposed development includes 2 main elements. There is the erection of a single storey rear extension and alteration to the roof which would include the hipped roof being replaced by a gable roof, together with the erection of a rear dormer.

The Council has not specifically objected to the single storey rear extension and front porch in its reason for refusal. Based upon what was observed during the site visit, there are no reasons to disagree with the Council’s assessment. In response to the appellant’s request, consideration has been given to the potential for a split decision to be issued. For such a decision to be issued the relevant parts of the appeal scheme must clearly be physically and functionally independent. In this case, the proposed single storey extension and front porch are clearly severable, and both physically and functionally independent, from the alterations to the roof. There exists, therefore, the potential to issue a split decision in this case.

There is guidance contained in the Council’s Harrow Residential Design Guide Supplementary Planning Document (SPD) stating that the preferred form of roof alteration to semi-detached or terraced houses is the extension of a hipped roof to form a gable with the addition of a rear roof extension. However, contrary to what the appellant claims, the alterations to the roof would be visible from both [address] and [address]. By reason of other alterations to roofs along [address], the proposed gable roof and the erection of a rooflight within the roofslope would not be so conspicuous so as to significantly harm the character and appearance of the streetscene. The assimilation of the proposed larger gable roof into the streetscene would be assisted by the use of suitable materials which could be secured by condition.

However, because of its scale and siting the proposed rear dormer would be a visually and physically conspicuous addition to the property when viewed from [address]. By reason of its width, the proposed dormer would not accord with the SPD’s guidance because it would not be set in from either the edge of the extended gable roof or the midline shared between the property and No.

There would also only be limited setbacks from the ridge and eaves. The proposed dormer would appear as an additional storey added to the property.

The bulkiness of this element of the appeal scheme would represent an unsympathetic and incongruous addition which would fail to respect the character and appearance of the host property and the terrace of dwellings within which it is situated. For these reasons, the proposed dormer would conflict with Policy CS.1B of the [name] (CS), Policy DM 1 of the Harrow Development Management Policies Local Plan (DMP) and the general guidance contained in the SPD. Amongst other matters these policies require development to be of high quality design which is not detrimental to local character and appearance and for extensions to respect their host buildings. Policy D3 of The London Plan is more particularly directed at optimising site capacity through a design-led approach rather than being a detailed development management policy for householder extensions.

Accordingly, it is concluded that the proposed alterations to the roof to form an end gable, rear dormer and the insertion of one rooflight in the front roofslope would conflict with CS Policy CS1(B), DMP Policy DM 1 and the guidance contained in the SPD because it would cause unacceptable harm to the character and appearance of the host property and the surrounding area, including the streetscene. Conversely, it is concluded that the proposed front porch and single storey rear extension would not cause unacceptable harm to the character and appearance of the host property and the surrounding area, including the streetscene, and, as such, it would not conflict with the design requirements of with CS Policy CS1(B), DMP Policy DM 1 and the guidance contained in the SPD. A split decision could, therefore, be issued in this case.

In the absence of an Appeal Questionnaire, no conditions have been suggested by the Council. However, consideration has been given to the need for necessary conditions, so far as they relate to the erection of the proposed single storey rear extension and front porch, which accord with the tests in the National Planning Policy Framework and National Planning Practice Guidance. A condition requiring these extensions to be erected in accordance with the submitted drawings is necessary for reasons of good planning and for the avoidance of doubt. The proposed external materials should match those of the host property and a condition is necessary to secure this.

Accordingly, the appeal is dismissed in respect of the proposed alterations to the roof to form an end gable, rear dormer and the insertion of one roof light in the front roofslope but allowed for the erection of the front porch and single storey rear extension.