13 Cavendish Place, Bath

13 Cavendish Place forms part of a Grade I series of early 19th century terraced townhouses by John Pinch the Elder, situated within the Bath conservation area and World Heritage Site. The terrace forms a significant 4 storey façade that gracefully steps up the north-south slope along Cavendish Road, with an articulated, curved corner façade that adjoins Park Place to the south and connects up with the Grade II terraces on Park Street and the Grade I ensemble at St James’s Square. The extent of proposed external works are restricted to the rear elevation of the building, which forms part of the eclectic grouped backland setting of Park Street, Park Place, and Cavendish Place, as well as the setting of the Grade II Cavendish Villa. The backland elevations of the terrace, whilst of a distinctly looser and more informal articulation and use of materials, remains evidentially significant as an indicator of how each dwelling was occupied and independently altered as part of a narrative of change. This includes a mixed variety of later additions such as extensions and garage buildings, as well as window replacements, resulting in a mix of fenestration styles. The terrace rear is clearly visible from the rear access route off Cavendish Road, but is otherwise largely screened from publicly-accessible viewpoints.

It is proposed to replace the existing single pane timber sash windows with multi-pane sashes at third floor level. The existing windows are indicated to not be original; BPT acknowledges that the single pane glazing style is a later intervention and not original to the early 19th design and appearance of the building. Where this does not result in a loss of historic fabric, we are therefore supportive of the principle to reinstate the traditional sash form and profile with heritage gain to the special architectural interest of a listed building and the group value of a Grade I terrace.

However, we maintain that appropriate details and drawings should be supplied as part of this application to fully assess the suitability of the proposed interventions, including existing and proposed elevations, and proposed sections and details to ensure that an acceptable glazing bar profile and thickness are selected.

Considering the limited public visibility across the rear of the townhouse and the third floor location of the windows to be replaced, further restricting visual scrutiny, there could be an opportunity to consider thermal improvements such as secondary glazing or slimlite double glazing, as part of a whole home approach to energy efficiency. However, this would be highly dependent on an appropriate assessment of potential heritage impact and harm, the public benefit of whole home carbon savings and the appropriateness of the glazing profile and finish.