How to Fix RAAC: A Proven Approach for Safer Structures

Reinforced Autoclaved Aerated Concrete (RAAC) was once considered an innovative building material. Lightweight and thermally efficient, it was widely used in UK schools, hospitals, and public buildings between the 1950s and 1980s. However, time has revealed its weaknesses—most notably, sudden structural failure. If your property contains RAAC, acting now is critical. So, how to fix RAAC? Here’s what you need to know.

Understand the RAAC Risk—Don’t Delay

RAAC has a lifespan of approximately 30 years. Over time, moisture penetration and steel reinforcement corrosion weaken its structural integrity. The Health and Safety Executive (HSE) has warned of the potential for catastrophic failure without visible warning signs.

At Structural Repairs, we’ve seen firsthand how neglected RAAC can endanger occupants and disrupt operations. Fortunately, early detection paired with targeted repair strategies can significantly reduce risk and restore safety.

Step One: Professional RAAC Survey and Detection

The first step in fixing RAAC is identifying its presence. This is not a DIY task. RAAC can appear similar to traditional concrete but behaves very differently under stress. Structural Repairs uses cutting-edge, non-intrusive technologies like 3D laser scanning, Ground Penetrating Radar (GPR), and concrete integrity testing to locate RAAC panels and assess their condition.

Our RAAC surveys reveal internal voids, delamination, and corrosion of embedded steel reinforcements. Most importantly, they guide our next actions with precision.

Step Two: Stabilise and Strengthen With Fortress Re:Grid

Once the risk is confirmed, it’s essential to act fast. Structural Repairs deploys the Fortress Re:Grid system—an advanced carbon fibre reinforcement solution. This technology is specifically engineered to fix RAAC issues safely and sustainably.

Re:Grid is applied to the surface of RAAC panels to distribute loads evenly, prevent shear cracking, and support compromised sections. Lightweight, non-corrosive, and fast to install, it’s the ideal fix for RAAC in sensitive or occupied environments. As the UK’s authorised distributor of Fortress Re:Grid, we ensure full compliance with BS EN 1504 standards for structural repair.

Step Three: Concrete Injection and Propping

In some cases, RAAC repair may involve resin injection or propping. Structural Repairs uses resin technology to bond fractured RAAC back together and prevent water ingress, a common culprit in structural degradation.

Emergency propping is also available when immediate risk is detected. Our rapid-response team can install supports within hours, protecting building users while permanent repairs are arranged.

Step Four: Ongoing Monitoring and Maintenance

Fixing RAAC doesn’t end with repair. To ensure lasting safety, we provide routine scanning, testing, and resurveying services. Our clients benefit from digital reporting and structural health monitoring that aligns with long-term maintenance strategies.

RAAC may be unpredictable—but with ongoing oversight, you can control the risks and extend the lifespan of your structure.

Why Choose Structural Repairs?

With over three decades of expertise, Structural Repairs is a trusted national leader in RAAC remediation. From emergency propping to carbon fibre reinforcement, we tailor every solution to meet your building’s unique challenges. Our work has been featured in The Times, and we proudly serve sectors ranging from education and healthcare to transport and heritage buildings.

We’ve completed RAAC repairs in critical infrastructure with zero downtime and 100% compliance. That’s the level of commitment and precision you deserve.

Take Action Today—Fix RAAC Before It Fails

RAAC is not a problem to ignore. It’s a ticking clock, and the time to act is now. Let Structural Repairs conduct a comprehensive survey, deliver expert repair, and provide peace of mind for the future.

Call 0300 030 1822 or email [email protected] to schedule your RAAC inspection.