Appeal 3281170

The appeal is dismissed.

I have taken the description of the development from the Council’s Decision Notice as this more accurately describes the elements which require planning consent. The Council’s description of development is also reflected on the applicant’s appeal form.

The main issue is the effect of the proposal upon the existing building and the character and appearance of the locality, with special attention to the Turnham Green Conservation Area (CA).

Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 (PLBCA), in respect of development affecting conservation areas, states that special attention shall be paid to the desirability of preserving or enhancing the character and/or appearance of the area.

The appeal site is located along [address], which according to the Turnham Green Conservation Area Appraisal (TGCAA) is located in the Devonhurst Character Area and on the accompanying map the appeal dwelling is noted as a ‘positive contributor’ to the character and appearance of the area. The TGCAA mentions that area was developed in the late nineteenth and early twentieth centuries on land previously used as experimental gardens by the Royal Horticultural Society. Most of the houses of the original development are either semidetached pairs or terraces of varying lengths, with a few detached units. Of note are the details of buildings within the area which have consistent roof forms, tall chimneys, finials, and use of materials. Particularly along [address], the dwellings are of high quality where their forms and Appeal Decision: APP/F5540/D/21/3281170 materials seek to emulate the original and larger dwellings found at the northern end and centre.

The use of traditional materials such as timber, brick, and clay roof tiles along with the similar designs reinforce an architectural integrity, uniformity and authenticity which creates a formal picturesque townscape which along with vegetated front gardens and street trees gives a leafy and distinctive character. The majority of roof planes along this section of [address] are uncluttered and authentic to their architectural integrity with unaltered roof planes being the dominant characteristic of the locality.

The appeal site displays a number of positive qualities which are experienced within the CA, being one of the characteristic semi-detached dwellings with a large two storey rear wing. The building contains many of the important design elements and original roof forms, large chimneys and use of original and authentic materials which reinforce its architectural integrity and contribute positively towards the local character, appearance and distinctiveness of the area.

In undertaking extensions to existing buildings, the London Borough of Hounslow Local Plan (LP) Policies CC1 and CC2 are design led policies which seek to achieve high quality design for new development which reflects the existing character and context of the locality. LP Policy CC4 relates to heritage assets and seeks that alterations and extensions demonstrate that regard is had to the significance of heritage assets and that development is in keeping with the building and wider area. LP Policy SC7 is specific to residential extensions and seeks that extensions do not harm existing character and appearance and also seeks that the Residential Extensions Guidelines Supplementary Planning Document 2017 (SPD) is taken into account in planning determinations. The SPD contains further specific guidance in relation to design principles and detailed design considerations that for roof extensions places an emphasis on subservience and responding to the existing site and context of the locality.

The proposed dormer roof extension would be erected to each of the rear roof planes of the rear wing. The dormer roof extensions would be large and would almost remove the entirety of the existing pitched roof of the dwelling along with the rear chimney stack which are positive features that contribute to the architectural authenticity of the existing dwelling and the significance of the CA. the proposed roof extensions would add a large amount of visual bulk and massing to the existing building which would be a dominant and disproportionate addition. [name] agree with the [name] of Case (SoC) that the proposed extensions would be set down from the ridge, and set in from the eaves, I do not agree that these elements would significantly reduce the amount of visual bulk to an acceptable level.

I note comments that the applicant seeks that ‘significant weight’ is given to the fact that the proposed dormer windows are located to the rear of the property where it is concealed from public view. Section 72 of the PLBCA or the National Planning Policy Framework (NPPF) does not seek to differentiate or give different weights according to where the extension is located. There is also no difference in policy terms in the duty or assessment of a CA in terms of whether it is within the public or private realm. As such the visibility of the Appeal Decision: APP/F5540/D/21/3281170 extension from the public realm is not something that would be afforded significant weight in this circumstance.

The applicant’s SoC notes that there are examples1 along the street of similar dormer roof forms which in the applicant’s opinion would set a precedence for the proposed development. I note however that according to both parties that some of the dormer roof extensions are historic and some do not benefit from planning consent, or have been undertaken before the recent change of policy position with the new extended CA adopted relatively recently in 2021.

Assessing the character and appearance of the locality on my site visit, it was evident that considering the area as a whole, the dormer roof extensions that have been constructed give a haphazard, cluttered and discordant appearance to the area that interferes with the inherent symmetry of the building which is a positive characteristic. I am therefore not of the same opinion as the applicant’s SoC that the limited number of dormer roof extensions placed on prominent rear roof pitches are part of the inherent character of the locality. It is clear to me that the current policy position as outlined in [name] CC1, CC2, CC4 and SC7 places an emphasis on subservience, scale, massing and form where the impact to prominent roof forms are an inherent consideration for the placement of dormer roof extensions. The existing dormer roof extensions in the area do however illustrate how dominant these extensions are to the existing building and roof form which has resulted in the loss of many architectural details which in turn interferes with the character and appearance of the area.

I am therefore not of the opinion that such roof alterations and including the neighbouring dwelling where similar scheme’s have been undertaken are part of the significance and positive characteristics and appearance of this particular CA. The presence of these extensions does not provide adequate justification for further detrimental elements to be situated on the appeal building.

I also note the submission of planning appeals2 which seek to illustrate that roof dormers and extensions are approved within CA’s. The amount of appeals submitted does indeed prove that roof extensions are approved within CA’s, however none of the submitted appeals are within this particular CA or have similar elements or considerations, with many of the examples being on the main roof, or having different design considerations. I am therefore not of the opinion that the considerations around the submitted appeals are analogous to the considerations around the appeal proposal and do not provide justification for the appropriateness of this scheme.

Taken as a whole, the proposed dormer roof extension would cause unacceptable detriment towards the architectural authenticity and integrity of the existing building and cause harm towards the character and appearance of the CA. Consequently, the proposal would be contrary to the [name] CC1, CC2, CC4 and SC7 which is accompanied by the SPD, all of which have been described previously. I therefore disagree with the applicant’s SoC that no harm would be caused. 1 Numbers 14, 24, 34, 36, 38, 44, and [address]. 2 Appeal Ref: APP/F5540/D/10/2139857 31 [name]; APP/F5540/W/16/3152949 [address] Rd; APP/F5540/D/16/3149354 66 [name]; APP/F5540/D/20/3244774 & APP/F5540/D/20/3244775 8 [name]; APP/F5540/D/17/3189182 92 [name]; APP/F5540/D/14/2212926 26a [name]; APP/F5540/D/14/2215986 67 [name]; APP/F5540/W/19/3222751 58B [name]; Appeal Decision: APP/F5540/D/21/3281170

Although serious, the harm to the heritage asset in this case would be ‘less than substantial,’ within the meaning of the term in paragraph 202 of the Framework. Paragraph 200 of the Framework states that any harm to, or loss of, the significance of a designated heritage asset requires clear and convincing justification. Paragraph 202 of the Framework requires that, where a proposal would lead to less than substantial harm, the harm should be weighed against the public benefits of the proposal.

The applicant has not outlined any public benefits of the scheme, however to me, the benefits of the scheme would deliver larger residential accommodation for the existing dwelling, as well as result in short term employment opportunities in the construction of the extension both of which are important planning policy objectives. However, these benefits may also be present in a more appropriately designed scheme and would not justify the harm I have identified.

I therefore find that the public benefits would not outweigh the harm to the CA. The scheme therefore conflicts with the Framework, which directs, at paragraph 199, ‘that great weight should be given to the asset’s conservation ... irrespective of whether any potential harm amounts to substantial harm, total loss or less than substantial harm to their significance’.

In conclusion on this matter, I consider the proposed development would cause less than substantial harm to the significance of the CA. It has not been shown that public benefits would outweigh this harm and so the proposal would conflict with the development plan.

The Applicant’s SoC notes the changes to permitted development rights to enable home owners to build an additional 2 storeys and seeks that I afford significant weight to this change to permitted development rights. [name] appreciate the government’s position and priority to create living spaces for growing families, this change to permitted development does not apply to buildings within a CA and as such is not afforded weight in this appeal.

I acknowledge and appreciate the comments from the applicant in their personal statement which accompanies their SoC regarding their personal needs, their specific situation and justifications for the proposed increase of space to cater for the care needs of an elderly relative. I have treated this situation as a material consideration to this proposal. Having reviewed these personal circumstances, I feel that there may be other ways of accommodating the applicant’s needs which may be more compliant with the policies of the development plan. There are consequently no material considerations that warrant a decision other than in accordance with the development plan.

For the reasons given above, I conclude that the appeal is dismissed.