Appeal 3297403

The appeal is allowed and planning permission is granted for raising ridge and roof lights on front slope plus a part single, part double storey side and rear extension; in accordance with the terms of the application Ref 21/4973/HSE, dated 14 September 2021, subject to the following conditions:

The development hereby permitted shall be maintained in perpetuity and in accordance with the approved drawings listed below, unless further planning permission is sought from the Local Planning Authority: • ‘Proposed Ground Floor Plan,’ A05 Rev1, Dated 05-NOV-2021; • ‘Proposed First Floor Plan,’ A06 Rev1, Dated 05-NOV-2021; • ‘Proposed Loft Plan,’ A07 Rev1, Dated 05-NOV-2021; • ‘Proposed Roof Plan,’ A08 Rev1, Dated 05-NOV-2021; • ‘[name], Rear, [name], Side B Elevation Plan,’ A10 Rev1, Dated 05- NOV-2021;

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

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.

Both parties draw my attention to a previous planning consent which was approved at appeal1 which consented the raising of the ridge by 0.35 metres, a rear dormer window and hip to gable roof extension. I note that the Council in their Officer report state that the raising of the ridge by 0.3 metres, the single storey rear extension and the two storey side and rear extension and rooflights would be appropriate and in accordance with the development plan. I have no 1 Appeal Ref: APP/N5090/D/21/3273438, Dated 10 August 2021 Appeal Decision: APP/N5090/D/22/3297403 reason to disagree with this opinion of the Council in these matters. Taking this into account, the only outstanding matter in dispute is with regards to the dormer window proposed to the rear of the main roof which will be the subject of this letter.

Taking the above into account, the main issue is the effect of the proposed dormer window upon the existing building and the character and appearance of the locality.

The appeal site is located along County Gate which forms a number of streets that contains formally laid out speculative housing which appears to date from the early to mid-twentieth century. The local area contains groups of terraces of 4 and 5 dwellings which have a symmetry in their placement with a consistent building line and setback with front gardens and low boundary walls. There are also visual gaps at the end of each group of terraces where glimpses to vegetation in rear gardens are experienced and is a positive characteristic of the area alongside trees to front gardens and street trees. The dwellings themselves have similar design characteristics with hipped roof forms with forward projecting gables with small ‘cat-slide’ rooves which take up the width of the dwelling. There is evidence of two storey side extensions to the ends of the groups of terraces which are not setback from the front façade and maintain visual gaps and the symmetry between the groups of terraces. There is also evidence of rear dormer windows to the rear roof plane which are not set in from the sides of the roof which according to the Council have been constructed under permitted development rights under the General Permitted Development Order ([name]) 1990 (GPDO).

The appeal site forms the end dwelling in one of the groups of characteristic terraces and has a later single storey flat rooved extension to the side of the dwelling. Next to the single storey extension is a visual gap to a private accessway to the rear of the dwellings along County Gate. The building comprises of a main two storey component with hipped roof with the forward protruding cat-slide roof which is characteristic of the dwellings within this locality.

In undertaking extensions and alterations to existing buildings, the London Borough of Barnet Local Plan Core Strategy (CS) Policy CS1 seeks to ensure that redevelopment delivers a high quality design by respecting local context and distinctive local character. The London Borough of Barnet Development Management Policies (DMP) Policy DM01 seeks to encourage development that provides positive characteristics such as understanding context, be high quality in design, form, scale, layout and the spaces around them, amongst others. These policies are supported by the Residential Design Guidance Supplementary Planning Document (RDG) which offers guidance on specific elements of designing new schemes and alterations, such as local character, scale, massing and height, materials, colour and architectural detailing, amongst others.

The RDG suggests that in order to be subservient that dormer windows should be set in at least 1 metre from the party wall, flank wall or chimney stack. I also note that the RDG also specifies that sometimes smaller setbacks would Appeal Decision: APP/N5090/D/22/3297403 also be suitable, depending on the layout and size of the resultant room. I agree with the Council that the dormer window is large, and is not a subservient addition in that it has no setbacks from the sides of the roof and would take much of the roof form and would be detrimental to CS Policy and CS5, and DMP Policy DM01, which is supported by the RDG as described previously. My attention is also drawn to the proposed plans and the appellant’s [name] which show that in the construction of the dormer window, the alteration would have an increased size of 23.3 cubic metres, meaning that the proposal could be developed in its current form under permitted development rights which are allowed under the GPDO.

With that said, and whilst I agree with the Council in the way they determined the application in line with the policies of the development plan; I have also taken into account the fallback position that if the appellant were to have constructed the approved scheme without dormer and once finished, constructed the rear dormer window under the provisions of the GPDO, then the same visual result and harm upon the character and appearance of the existing building and greater locality would be achieved. With this in mind it would be unreasonable for the appellant to construct the extension only to then need to alter it again to enact permitted development rights under the GPDO and achieve the same result.

In this particular instance the GPDO and the resultant fallback scheme achievable under this Order carries significant weight as a material consideration to the determination of this scheme. This decision has been taken in light of these specific factors and should not be taken as a commentary on the future application of this policy and its association with the provisions of the GPDO. Therefore, and in conclusion of this matter; whilst the proposed development would conflict with the development plan, this is outweighed by other material considerations as explained above.

For these reasons, and having considered all matters raised in evidence and from what I saw during my site visit, I conclude that the appeal should be allowed and planning permission granted.

The Council in their Appeal Form response detailed that should the appeal be allowed, that conditions regarding time limit, approved plans and materials which match existing be placed on any decision notice. I have considered the conditions as specified in the beginning of this letter in accordance with the Planning Practice Guidance (PPG). Condition 1 and 2 which specifies a time limit and approved plans are standard conditions which notes the approved plans which are necessary for the avoidance of doubt and in the interests of proper planning. Condition 3 seeks that the scheme is constructed in matching materials which are necessary as this condition enables the development to fit in with the character and appearance of the existing dwelling and the locality.