ESSENTIAL repairs at Wrexham Maelor Hospital due to crumbling RAAC found in the roof are expected to cost around £400,000.
Reinforced Autoclaved Aerated Concrete (RAAC) – commonly used in construction between the 1950s and 1990s as a cheap, lightweight, easy to use alternative to reinforced concrete – has recently been found to crumble over time leading to problems at many public buildings including schools and hospitals across the UK.
In January 2025 RAAC was discovered in the roof of Wrexham Maelor Hospital’s Pathology Unit. Not open to the public, the unit is primarily a laboratory space for blood work, fertility testing and immunology investigations.
Now 18 months later Betsi Cadwaladr University Health Board has put the repair work out to tender. It is seeking a construction firm able to repair and reinforce the roof – while the building remains operational as a laboratory – for around £400,000.
An inspection by a specialist surveyor on behalf of BCUHB originally identified the problem last year. As soon as it became aware of the issue, the health board installed props to shore up the roof area, which includes heavy air conditioning units.
All access to the roof was restricted and North Wales Fire Service warned not to place any load upon the roof section should they need to attend.
If a contractor can be found, work is expected to begin in September to be completed by the end of March 2027.
“The project comprises structural intervention works beneath the existing RAAC flat roof structure serving the main Pathology Laboratory,” according to the documents.
“The laboratory will remain fully operational throughout the works, requiring carefully managed sequencing and environmental controls. The project scope also includes internal refurbishment works.”
