How do you redevelop Wales’ favourite museum?

The museum features a Grade II listed modernist main building as well as more than 40 other listed and historic buildings that have been carefully dismantled from across Wales and re-erected on site. The redevelopment project was designed to improve the relationship between the museum’s main building and its surroundings and to disperse visitors more effectively around the site, providing capacity for sustainable growth over the coming 50 years. Our client, National Museums Wales, also wished to improve educational facilities for the large numbers of visiting school children and to create a new space for archaeological exhibits. These have been relocated from a Cardiff city centre site as a way of bringing artefacts from 230,000 years of Welsh history together in one place.

Integrating new and existing structures

Due to the nature of the museum exhibits, new mechanical, electrical and public health systems were designed to deliver specific environmental conditions. Our team was able to detail the extension structure to integrate these new building services systems seamlessly within the existing building fabric, thereby protecting listed façades.

We consulted extensively with the museum and exhibition teams to ensure building services in the galleries met current exhibition requirements and would offer flexibility for the future, should spaces be reconfigured. To achieve this, we minimised the visual impact of the building services, concealing connection points behind walls and within ceiling formations.  A grid of power and data was provided within the walls, into which cut-outs can be made to add future connections.

Structural challenges

The main building’s original fabric was in a poor condition. Its 1970s concrete structure was degrading and there were leaks into gallery spaces. Without engineering record drawings to work with, our team used core sampling and reinforcement scanning to confirm the loading capacity of the structure and to identify areas where the original design was deficient. These were rectified as part of the works.

Studies showed that the floor loading in some of the gallery spaces was insufficient for the display of heavy exhibits. Through our study of the structure and discussions with the museum’s exhibition team, we were able to position a number of significant and heavy standing stones within the gallery with only local discrete slab strengthening. To ease installation these exhibits were pre-positioned in the space and built around. In new areas of the building we reviewed the museum’s collections to determine a higher loading allowance that offers curators greater flexibility for future updates to the exhibitions while balancing cost and efficiency.

3D modelling was used to assist with the integration of completely new services routes and with coordination of connections between new and existing structures, where varying wall, floor and roof levels and angles created complex geometries.

Both Y Gweithdy and the site’s main building are served by rainwater harvesting systems. Environmental conditions in the main exhibition space are maintained by an air source heat pump system, while the museum’s existing onsite solar photovoltaic generation has been reintegrated with the building and a new combined heat and power system installed. Both buildings have secured the targeted BREEAM Excellent and EPC A rating that formed part of the original project brief.