Stanton Williams completes Wiltshire Council’s new offices on historic site in Salisbury
The Bourne Hill Offices were commissioned by Salisbury District Council to redevelop a sensitive historic site at Bourne Hill, Salisbury, creating new high quality centralised offices to significantly reduce costs while at the same time improving customer service and supporting more flexible ways of working. The building is set within a sensitive medieval city site and includes the refurbishment of a Grade II* listed building with a contemporary new build, respecting the mansion and the grounds. The development, completed in September 2010, forms part of a campus and operational delivery programme, to reduce the number of council offices – decreasing the council’s carbon footprint and saving an estimated £85 million over 25 years on maintenance and revenue costs.
Cost-efficiency was essential to meet local authority budget requirements, while still achieving high quality spaces with durable, low maintenance materials. The new highly flexible and adaptable spaces within the new build provide office accommodation with view of the garden for approximately 500 staff and a registrar’s office for weddings and ceremonies. A high performance façade minimises heat loss and solar gain, but allows a high percentage of daylight through to minimise the need for artificial lighting. On the western façade external blades form a colonnade, and are clad in Portland stone to reflect materials used in the refurbished listed building.
Its use creates a striking visual link between old and new. The colonnade creates an attractive place in which to walk at the boundary between architecture and nature, with its columns framing glimpses of trees in the garden beyond resulting in a rich interplay of transparency, reflection, light and shadow. The design team worked closely with English Heritage to develop a series of delicate repairs to the historic house, avoiding any wholesale re-building of the structure, and used traditional materials such as hair lime plaster, welsh slate, lead guttering, timber laths and local stone.
The new building steps back as it meets his historic neighbour, with a narrow glazed section delineating the boundary between the two. The exposed in-situ concrete uses 55% GGBS cement replacement mix, which creates a building with a high thermal mass and negates the need for mechanical air conditioning. It is believed that the use of GGBS cement replacement reduced the amount of embodied carbon in the structure by about 20%.