30 Park Avenue, Lyncombe, Bath

30 Park Avenue forms part of a late 19th/early 20th unlisted residential terrace, situated within the Bath Conservation Area and World Heritage Site, on the northern extent of the Bear Flat character area. The terrace is fairly typical of its typology with a regular, symmetrical façade in Bath stone ashlar incorporating a two-storey bay window. The rear elevation features two storey ‘paired’ stack elevations; no. 30 is the exception due to its end-of-terrace position in that it features a single two-storey stack extension which does not form a pair with an adjoining neighbour. This building type remains very typical of Bath’s later Victorian and Edwardian residential expansion, particularly to the south and west of the city centre.

No. 30 is tightly constrained by surrounding development. To the south, the building frontage immediately looks onto a high coursed rubble stone boundary wall associated with a group of detached 20th century dwellings at an elevated ground level just off Hayesfield Park. The western boundary of no. 30 is enclosed by the adjoining built form and garden setting of The Coach House, as well as the garden of 1 Crescent View. The north, rear elevation of no. 30 overlooks the rear of Magdalen Avenue; however, it is notable that this elevation does retain some limited public visibility in views from Madgalen Avenue, and further north from the A367. The terrace as a whole contributes to general townscape and roofscape views as experienced from Oak Street; within these longer-range views, no. 30 remains imperceptible as a single dwelling but can be considered to somewhat contribute to the overall, cumulative uniformity of appearance and scale of the built environment in this area.

In response to the Climate Emergency, BPT is supportive of the principle of retrofit works to improve the energy efficiency and thermal performance of Bath’s existing building stock, where this does not result in adverse impact to the special interest of a listed building or the character and appearance of the conservation area.

We note that the building as existing currently experiences damp and mould issues due to the exposed western gable end, with consequent impact on the internal living conditions of the property. We are therefore supportive of proposals that seek to improve the liveable standards of this housing type and subsequently ensure its long-term continued occupation, whilst considering ventilation and the ‘breathability’ of porous Bath stone. We emphasise the importance of finding solutions to make improvements to Bath’s existing housing stock where reuse and retrofit remains a greener solution than dependence on new-build housing, as well as securing a sustainable, functional future for its traditional and unlisted buildings. However, we maintain the requirement for informed consideration as to why specific measures have been selected in relation to their context to demonstrate that these would appropriately complement the behavioural properties of this traditional building (ie. solid external walls in porous stone) and its appearance and character.

It is proposed to apply a hemp-lime insulating render to the external west and north walls. The works seek to address water ingress and associated damp and mould issues, to which the west gable end is particularly susceptible, as well as improving the consistency of the internal building temperature. BPT highlights the potential for some visual impact where a render would be applied over the existing Bath stone ashlar external wall. The material character of the area is predominantly Bath stone which, whilst including buildings of a later 19th/20th century date, reinforces the material homogeneity of the Georgian city in wider townscape views. The use of an external render must therefore be carefully considered in relation to the degree of visibility and quality of views, as well as the identified special characteristics of the built environment. We maintain that this assessment should be made on a case-by-case basis, and judgements made for one site/property should not be considered to establish a standardised precedent that could be applied anywhere.

The west gable end of no. 30 is well-enclosed by adjoining development, and any alterations to this elevation would be subject to localised, private views. The north elevation is included within very limited mid-range views to the north which can only be ‘glimpsed’ from particular spots in the streetscape; these views form part of the ancillary, built backdrop of Magdalen Avenue and the A367 but are not of high significance on their own. Where the proposed render treatment is of an appropriate colour match and detail (eg. scored in an ashlar pattern), we conclude that this would result in very limited harm to the perceived character and appearance of the conservation area and the terrace’s presence in wider townscape views. However, we strongly recommend that further evidence of the results of installing similar insulation systems elsewhere should be provided for comparison and to appropriately underscore the proposed benefits as part of the planning balance. We further highlight the importance of ensuring a well-detailed finish to minimise risks such as cold bridging at external corners of the building, as well as how the proposed render system would relate to window/door openings and the roof eaves.

It is also proposed to add two additional PV panels on the south roof slope. Whilst there is a general preference for PV panels to be located away from the principal frontage (eg. side and rear elevations), there are a number of considerations in relation to the particular characteristics of the site. The south elevation is well-enclosed by surrounding development and would be screened in wider views, where the north elevation is open to some mid-range views from surrounding terraced streets. No. 30 remains tucked away at the far end of Park Avenue and is of limited visibility in streetscape views as taken at the junction of Magdalen Road, where the homogenous appearance and character of the terrace would be sustained. We note that where this installation can be concluded to be of less than substantial harm, this would be outweighed by the benefits of on-site ‘green’ energy generation and associated reduction in carbon emissions, as well as maximising the proposed panels’ output by making use of the building’s south-facing roof slope, and resulting contributions towards B&NES Council’s Net Zero objectives. It is indicated that panels have already been installed in this location, and we recommend that any further panels should be of a matching model and/or design to ensure a coherent appearance and avoid unnecessary visual contrast.