Reinforced autoclaved aerated concrete (RAAC) is a cheaper alternative to standard concrete and was mostly used in flat roofing. It is aerated and less durable than standard concrete, and can be susceptible to structural failure when exposed to moisture
It is suggested that between 5-10% of all public buildings, which would include social housing, built in the 1950-1980s is likely to contain RAAC.
The Regulator of Social Housing has made it’s position clear that all RP’s need to be aware of the risks posed by this potentially dangerous form of lightweight concrete in its homes and must find a) find out if any of its home contain RAAC and b) if found, which risks it poses to the safety of its tenants.
Any homes which are considered to be unstable or otherwise pose a risk to tenant safety may potentially be considered under the Building Safety Act 2022 which prescribes a retroactive 30 year limitation period for pursuing claims against anyone who took on work in connection with those units.
Further updates are expected as more RPs assess their housing stock and report any findings to the Regulator.