Flat 9, Ladymead House, 110-112 Walcot Street, City Centre, Bath

Ladymead House is a Grade II early-mid-19th century house and former Women’s Penitentiary, now Housing Association accommodation, situated within the Bath conservation area and World Heritage Site. It forms the adjoining corner of the principal street-facing elevation of the Grade II mid-19th century Penitentiary Chapel which has also been amalgamated to form additional Housing Association accommodation. Ladymead House includes the two rear wings tucked behind the chapel that form an enclosed courtyard; both wings appear to be contemporaneous with or slightly later than the street-facing section of both buildings, with a less formal and simpler construction in a mix of Bath stone ashlar and rubble stone. A more formalised window layout and fenestration of six-over-six sash windows has been retained on the courtyard-facing elevations, with a mix of window sizes and styles on less significant ‘rear’ elevations that are now visible from areas such as Chatham Row.

In the light of the declared Climate Emergency, BPT is generally supportive of retrofit measures that protect elements that contribute to the special architectural and historic interest of a listed building; alterations are expected to be visually coherent with the character of the building, and the wider shared character of the two listed buildings and surrounding conservation area.

We acknowledge that the existing windows proposed for replacement are non-historic in origin and are in a poor condition, necessitating replacement.

This offers a positive opportunity for the implementation of energy-efficient retrofits without the loss of historic fabric, and the reinstatement of timber-framed sash windows with associated heritage gain.

We note the current need for the improved thermal performance of the building. This application could establish a suitable template for the future replacement of other non-historic windows where appropriate as part of ongoing upgrades, and therefore we maintain the importance of getting the design of the proposed replacement windows right to ensure a consistent and coherent approach to the listed buildings that sustain their historic and architectural interest.

We additionally emphasise the importance of a more holistic ‘whole house’ approach to cumulatively improve thermal performance and residential comfort.

We acknowledge that the works are focused on the internal elevations of the southern wing, and therefore would not be publicly visible. However, we maintain that the replacement windows should be visually sympathetic to the traditional window profile of the listed buildings in material, construction, and fenestration style to retain a harmonious aesthetic. This can be achieved through the use of an appropriate style of glazing bar thickness and profile to ensure the timber frame isn’t overly heavy or blocky in appearance.

We note that measurements of the windows as existing have not been provided, and therefore the extent of change proposed by this application remains unclear. There are no existing window details, close up photographs or measured sections against which the proposed sections can be compared. We would therefore recommend that sections of the existing windows are submitted to enable the LPA to make a proper assessment regarding any potential change in glazing bar thickness and consequently the overall visual character of the windows.

BPT is concerned regarding the proposed insertion of ‘standard’ 24mm double glazing without appropriate consideration or assessment of the potential detriment to the appearance or significance of a listed building. These are typically not as sympathetic to the character of a listed building due to their chunkier profile and ‘double reflection’. The proposed windows appear to be a standardised specification and are not tailored to the specific architectural interest of the Grade II building and its wider terraced setting. We therefore strongly recommend the consideration of a slimmer profile 14mm glazing as a more sensitive alternative.

We additionally feel the use of applied glazing bars, rather than traditional through glazing bars, is inappropriate and would be an incongruous visual addition to the building and its established fenestration style. We strongly recommend that this aspect of the scheme is amended to include through glazing bars to ensure a consistent, homogenous finish and the associated architectural interest of both listed buildings.

We suggest that further measurement details are provided regarding the proposed glazing bars. We note that whilst the limited public visibility does result in lessened harm if the glazing bars are of a slightly greater thickness (see the Delegated Report for 3 Lansdown Place East, application 20/00024/LBA), it remains significant to ensure a relatively coherent finish in which the replacement windows sit comfortably within their architectural context.

We are resistant to the introduction of timber window sills. Stone sills, either painted or unpainted, remain a distinctive feature along terraces within Bath; the addition of a timber sill over the existing stone sill would be inappropriate. We strongly suggest this aspect of the scheme is omitted.

This proposal, if got right, could help provide an invaluable opportunity to monitor the thermal and acoustic efficiency of the windows, before and after, whilst also observing any additional repercussions such as changes in humidity levels. This information could then be used to more accurately assess the suitability of slimlite installation in Bath’s historic building stock.

BPT is very interested in working with the applicant to reach an acceptable solution and getting better understanding of the existing window condition and design.

Therefore, whilst we are supportive of the principle of the installation of more thermally efficient glazing, we are resistant to the installation of standard 24mm glazing and strongly recommend consideration of a more sympathetic slimlite alternative. We strongly encourage that the proposed glazing bar design is reconsidered and alternative glazing suppliers consulted to find alternative options to appropriately balance limited less than substantial harm to a listed building against the potential public benefit.