What is RAAC and how is it identified?
RAAC is a lightweight, porous type of concrete commonly used in the construction of schools, hospitals, hotels, theatres, and housing from the 1950s to the mid-1990s. While most commonly found on flat roofs, it can also be located in pitched roofs, floors, or walls.
Key Identification Markers:
- Typically 600mm wide concrete panels.
- Distinctive V-shaped grooves at regular spacing.
- White or light-grey in appearance (if unpainted).
- The inside appears “bubbly” with no visible stones (aggregate).
- Mention of manufacturers such as Siporex, Durox, Celcon, Hebel, or Ytong in legacy building drawings.
Note: If your inspection requires accessing areas behind ceilings or finishes, always consult the building’s asbestos register beforehand. Our team can manage this risk safely on your behalf.
Our End-to-End RAAC Service
At Frankham, we understand the importance of minimal disruption. We plan our investigations carefully to ensure the ongoing safe use of your assets while we work.
Comprehensive Inspections & Reporting
We conduct meticulous site investigations to identify the exact locations and condition of RAAC within your building. We produce detailed reports that categorise your specific level of risk in strict accordance with IStructE standards and current BRE guidance.
Expert Advice on Temporary Measures
When a risk assessment indicates an immediate need for action, our engineering team rapidly designs temporary propping and safety measures. These solutions often permit the continued safe use of your property while permanent measures are finalised.
Permanent Strengthening & Replacement Design
Every building with RAAC issues is unique; there is no single standard fix. Based on our detailed investigations, our structural engineers will design and specify the optimal permanent solution, whether that is targeted strengthening or complete roof replacement
Turnkey Management & Additional Services
Through our wider multi-disciplinary group, we can manage the entire remediation project. This includes procuring suitable contractors, managing the diversion of electrical services, handling asbestos management, and designing new architectural finishes.
“We had over 110 nationwide government buildings of various age and size that needed to be urgently assessed with respect to risk from failure of RAAC roofs. The Frankham Structural Engineering team were reactive to our needs, and we were able to complete the surveys safely, issuing reports in short time all to the satisfaction of our client.”
Gareth Blore, Programme Director at Mitie
Meet our RAAC plank structural surveys lead
