Appeal 3280017

The appeal is allowed and planning permission is granted for a first floor side to rear extension; single and two storey rear extension; rear dormer; rooflights in front roof slope; conversion of garage to habitable room with installation of window to front; re-location of main entrance; external alterations in accordance with the terms of the application [name]/1715/21, dated 23 April 2021, subject to the following conditions:

The development hereby permitted shall be carried out in accordance with the approved drawings listed below: • Site Plan Proposed, [name]. 20_138_P0, [name] 2020 • [name] – Ground and [name], [name]. 20_138_P1, [name] 2020 • [name] – Loft and [name], [name]. 20_138_P2, [name] 2020 • [name], [name]. 20_138_P3, [name] 2020 • Proposed Section A-A, [name]. 20_138_P4, [name] 2020

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.

The description of the development has been taken from the Council’s Decision Notice as this more accurately describes the elements requiring planning permission. It is noted that this description is also mentioned on the applicant’s Appeal Form. Appeal Decision: APP/M5450/D/21/3280017

I note that the Council in their refusal reason reference the National Planning Policy Framework 2019 (the Framework). Since the submission of the appeal, the 2019 version of the Framework has been superseded by the 2021 version. I have considered the appeal on this basis and refer only to the updated 2021 Framework within my decision.

The main issue is the effect of the proposed development upon the character and appearance of the host building and the surrounding locality.

The appeal site is located along [address], which forms one of a number of streets in the local area that contains formally laid out speculative housing which appears to date from the mid-late twentieth century. The dwellings along [address] typify buildings and construction of this era with functional two storey dwellings with hipped roof forms with the use of brown brick, render and steep roof pitches. The dwellings have been positioned in a regimented fashion with similar front and rear setbacks, and gaps in between dwellings which allows views to the tops of vegetation within rear gardens. It would appear that dwellings were originally a much more modest size with a number of dwellings along [address] having undergone a number of extensions which have changed the character somewhat to larger dwellings with a reduction of visual gap between properties. Despite this, the regimented layout of dwellings in their positioning with similar setbacks, hipped roof forms, building height and the use of well planted front gardens with low boundary walls presents a leafy and open character where gaps in and around properties are part of the positive qualities of the area. These positive qualities reinforce local character and distinctiveness.

The appeal site displays a number of positive qualities which are experienced within the street scene, and appears to be one of the original properties of the estate with two storey construction, a steep pitched hipped roof which maintains larger setbacks to the side boundaries, with visual gaps in between the properties and the regimented layout in terms of setback from [address].

In undertaking extensions and alterations to existing dwellings, the [name] 2012 (CS) Policy CS1 (B) seeks that new development respond positively to the local and historic context in terms of design, spacing, density and siting which reinforces positive attributes of local distinctiveness. Policy DM1 of the Harrow Development Management Policies Local Plan (LP) also seeks to establish high quality design that has regard to massing, bulk, scale and height and their relationship to the surrounding layout. These policies are supported by a Residential Design Guide Supplementary Planning Document (SPD) which provides further guidance and advice with regards to appropriate design principle employed in extensions and alterations.

The proposed extension would be large in that it alters and extends much of the dwelling, particularly to the side and rear. However, much of the extensions proposed would be constructed upon the existing footprint of the building and are designed in a way that the extensions would be proportionate to the dwelling with a characteristic hipped roof form which is set under the apex of the roof which assists in giving a coherent design approach that assists in Appeal Decision: APP/M5450/D/21/3280017 reducing visual bulk and massing. When experienced within the context of the locality, the proposed development would be in keeping with its surroundings in terms of the height, materials, setback, roof forms and visual gaps in and around the buildings which are important elements of local character and distinctiveness in this particular street scene.

With regard to the proposed rear dormer window, whilst the SPD recommends that dormer windows should be set back within 0.5 metres of the edges of the roof, the SPD also states that consideration will be given to the ‘type of roof, the scale of proposals, and the character/appearance of the house and those adjacent1’. In this particular case, whilst the setback does not conform to the recommended setback as suggested by the SPD, the rear dormer window is of a scale that is sufficiently setback within the plane of the roof and is subservient to the existing roof form and which reflects the general nature of development found within the locality.

In conclusion of this matter, the proposed scheme would present an appropriate architectural approach which is subservient, high quality and would be in keeping with the site and its context. Consequently, the scheme would be made in accordance with CS Policy CS1 and LP Policy DM1 as described above. The scheme would also be compliant with the design policies of the Framework and Policy D3 of the London Plan which seeks a design led development which reflects local character and context.

Paragraph 195 of the Framework seeks that in determining applications, that consideration be given to the setting of heritage assets where this makes a contribution to the significance of a designated heritage asset. The rear boundary of the appeal site lies on the boundary of the Cannons Park Estate Conservation Area (CA). The Canons Park Estate is a speculatively designed estate of high social status with Tudoresque styled dwellings which have an emphasis on a tranquil environment with street trees and well vegetated gardens, and public spaces creating an idealised Sylvan development which is distinct from the surrounding later residential development. Whilst the setting of the CA does make a contribution to its significance, in my opinion the proposed development when seen in the context of the surrounding development also along the edge of the CA, would be of neutral harm to the significance of the CA from development within its setting.

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, subject to the conditions as detailed previously.

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). Conditions 1 and 2 are standard conditions which set the standard time limit and approved plans which are necessary for 1 Paragraph 6.67 Appeal Decision: APP/M5450/D/21/3280017 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.