Thomasons acted as structural engineers for the £4.5m redevelopment of Norton Priory Museum in Runcorn, a joint venture between Norton Priory Museum Trust Ltd and Halton Borough Council. Designated as a Scheduled Monument, the site contains the remains of a 12th century monastery and is renowned as Europe’s most excavated monastic site. The museum complex comprises the historic Grade I Listed undercroft and a steel-framed 1980s building that houses the museum.
Thomasons was responsible for the design of several structural aspects of the project including a new structure to link the undercroft and museum, a new steel portal framed building above the undercroft for exhibition space, a double-height space to house the new café, refurbishment of the 1980s museum, stabilisation of the ground floor of the undercroft, which had suffered from settlement and new drainage.
Working on a Grade I listed building and Scheduled Monument site severely restricted the intrusive work that could be undertaken. The team worked closely with Historic England as work to the undercroft and in the ground required Listed Building Consent and/or Scheduled Monument Consent.
An archaeological exploration was conducted before works started on site and new foundations were dug or supervised by an archaeologist.
During this work, a medieval wall was found to be more intact below ground than had been anticipated; this meant that the front glazed elevation could not be supported directly onto the ground and had to be suspended from the first-floor walkway which links the new lift shaft with the new exhibition space on top of the undercroft.