18 Upper Borough Walls, City Centre, Bath
18 Upper Borough Walls forms one of a pair of Grade II mid-18th century houses with commercial ground floor use and shopfronts, situated within the urban core of the Bath conservation area and World Heritage Site. The buildings form part of a small pocket of retail use in this area, characterised as independent businesses with small scale and individual shop fronts.
BPT is supportive of the provision of “affordable rent” dwellings, where this is policy-compliant with other considerations such as the change of use from office space within the city centre. We are keen to see the delivery of genuinely affordable housing in Bath and therefore recommend that further details are provided as part of this application to define what constitutes “affordable rent” and how it would be secured as part of a planning permission.
There is a preference for long-term or ‘in perpetuity’ affordable housing to ensure that future numbers of affordable housing are appropriately secured.
However, we are disappointed that this scheme misses the opportunity to maintain and enhance an active commercial ground floor use within the Bath city centre. Both 18a and 18b are indicated to have been in commercial use from the late 19th century and as such are an established aspect of Bath’s commercial streetscape. In accordance with Policy CP12 of the Core Strategy and Placemaking Plan, “uses which contribute to maintaining the vitality, viability and diversity of centres within the hierarchy will be encouraged. Active ground floor uses will be maintained and enhanced.” The residential change of use would no longer result in an active ground floor use to the detriment of the character and appearance of Bath’s retail centre. This application has not provided adequate evidence to show that retail use is not viable on this plot (eg. the unit has been unsuccessfully marketed for at least 6 months). Whilst the principle of residential use is acceptable across the under-used upper floors, we therefore strongly emphasise consideration of a mixed-use model in which the active retail use of the ground floor is retained with benefit to the sustained character and appearance of the conservation area.
From the photographs provided, the door opening in the south elevation appears to date to the 1900s. Whilst the door is likely unoriginal, the door surround and lintel appear to be unaltered and indicative of one of the original access points into the shop premises. Blocking up the doorway would considerably alter the appearance of the building in the setting, which as a corner building, makes a positive contribution to the character. The door should be retained in situ; an insulated stud wall could be inserted behind as a reversible measure to futureproof the future use of the building without overt harm to its historic character.
Sections are required for the proposed alterations to the Victorian shopfront on the west elevation to ensure that the thickness and profile of the proposed transom bar is coherent with the historic shopfront character of the listed building. Further clarification is required as to how the transom bar would be installed; we maintain the use of applied glazing bars in a listed building is inappropriate.
We have some concerns about the awkward proportions of the proposed window and window to replace the modern shopfront in the south elevation – given historic precedent demonstrated in 1930s photographs, there could be an opportunity to reinstate a traditional style timber ‘shopfront’ where the door and window are integrated into one. This would retain the shopfront appearance of the building as well as evidence of its historic use.
Whilst BPT does not typically comment on internal alterations without the benefit of a site visit, we have some concerns regarding the lack of historic assessment for proposed internal works, such as the removal of partition walls at lower ground floor from the store room. It is unclear as to whether these partitions are part of the historic function of this basement space; the proposed floor plans indicate that removal “is likely to require a new beam above”, indicating that these could be significant masonry insertions and possibly of some evidential value. Similarly it is proposed to install a cavity drain membrane along the southern wall with inadequate assessment of the condition of the existing wall and how this would be affected by a membrane overlay. As such, we consider that further assessment of the proposed impact of works is required to appropriately justify potential harm to historic fabric and associated significance.
The D&A Statement indicates the proposed implementation of sustainability measures, including double glazing, internal insulation, and roof-mounted PV panels. We commend the opportunity for energy efficient retrofits, pending further details as follows:
Further information is needed regarding the proposed type and thickness of internal insulation to be used and how it would interact with any retained historic features and more complicated areas such as window reveals and surrounds. We maintain that the proposed insulation type should be coherent with the breathable qualities of the historic building fabric to minimise the risk of future issues such as increased condensation or damp. The use of internal insulation is not indicated in the proposed floor plans and we recommend this is appropriately amended to show where internal insulation would be installed.
The D&A Statement proposes the use of double glazed sash windows, but the proposed plans indicate that the existing windows are to be refurbished and draught proofed. This aspect of the scheme should be clarified; where double glazing retrofits are proposed, we maintain a preference for slimlite double glazing as a more visually coherent option in a listed building, pending further drawings and sections. Suitability of replacement is also dependent on whether this would result in a loss of historic glazing.
The installation of PV panels on the flat roof would likely be of negligible public visibility from street level and would therefore be acceptable. We recommend that further material details are submitted regarding the proposed fixing and appearance of the panels to allow for a fully-informed assessment of the proposed works, and to ensure that the works are compliant with Policy SCR2 of the Core Strategy and Placemaking Plan. The use of monochrome panels with a matte, non-reflective finish is preferable.