Richmond upon Thames Council's Planning Committee has approved plans to convert the historic Hampton Water Treatment Works into 36 new homes and flexible business space. The decision, made on Wednesday, July 15, 2026, grants full planning permission and listed building consent for the redevelopment of the Grade II listed site.
The project will see the conversion and extension of the Ruston and Ward Buildings, and the Karslake Buildings, which have been on Historic England's Heritage at Risk Register due to their deteriorating condition. The development aims to secure the long-term future of these buildings, which are considered to be architecturally significant examples of Victorian industrial heritage.
These buildings are noted for their Italianate style detailing, including ornate cast-iron railings and fine Italianate forms. They represent early and rare survivals of waterwork construction following the Metropolis Water Act. Internally, they feature large open-plan spaces, visible roof trusses, extensive natural light, original or replica windows, surviving machinery, glazed brickwork, gantry cranes, Tuscan columns, and decorative brickwork. The Ruston & Ward Building, for instance, is a square single-storey structure in gault brick with round-headed windows and pilasters, featuring a central square tower with arcading. The Karslake Building, originally two engine houses, is described as being of gault brick with stucco cornices and window dressings. The Beam engine house within the Karslake complex retains wrought iron roof trusses, a large gantry crane, Tuscan columns, and original steel staircases.
Despite concerns raised about the loss of employment land and the level of affordable housing, the committee voted unanimously in favour of the plans. Officers noted that the proposed harm to the heritage assets was considered less than substantial
and outweighed by the benefits of preserving and repairing the buildings. Measures to mitigate this harm include minimizing alterations to historic fabric, revising roof extension designs to reduce visual impact, and retaining key original features such as glazed tiling, surviving equipment, wrought iron roofs, gantry cranes, Tuscan columns, and metal staircases. Proposed lifts are strategically located to avoid impacting original features, and secondary glazing will be used to retain original windows. A Conservation Management Plan will be submitted to detail the significance of the buildings and their maintenance regime.
The scheme will provide 36 residential units, including two three-bedroom social rented homes, which represent 5.5% of the total units. This falls below the Local Plan policy requirement of 50% for former employment sites. A Financial Viability Assessment, using a conservation deficit methodology, concluded that this was the maximum affordable housing that could be delivered due to the high costs associated with renovating the listed buildings. This assessment was independently reviewed and confirmed by the Council's viability consultants, Bespoke Properties.
A net loss of 1,815 square metres of employment floorspace is expected, but the development will retain 310 square metres of flexible business space (Use Class E(g)). This space is intended to accommodate small and medium-sized businesses and a range of commercial activities, designed to be flexible and adaptable for various uses, including office, research and development, and light industrial activities. It could also support smaller local businesses and co-working arrangements, benefiting from a dedicated pedestrian entrance off Lower Sunbury Road.
The proposal also includes highway improvements, such as widening the footpath along Upper Sunbury Road and the provision of a new signalised pedestrian crossing. Additionally, the scheme includes the repositioning of the site boundary brick wall and railings to facilitate these highway works. The development also proposes the creation of two children's play spaces, one at the front of the Ruston and Ward building and another at the rear of the Karslake buildings.
Councillor Roberts, the interested ward councillor, endorsed the scheme, highlighting the need to preserve the heritage asset and address the concerns of neighbouring residents. We are running the risk of a significant heritage asset rotting away,
he stated, emphasizing the distress caused to neighbours by the site's current dilapidated state.
Further details of the planning application and reports can be found in the Public reports pack for the Planning Committee meeting on Wednesday, July 15, 2026. The Agenda frontsheet for the same meeting is also available.
