Reinforced Autoclaved Aerated Concrete: guidance and insurance implications

Lockton Global Real Estate and Construction provide important information following the recent safety concerns and increased news coverage on buildings containing Reinforced Autoclaved Aerated Concrete (RAAC). Although the majority of the properties which contain this material are thought to be public buildings, there are also privately owned buildings built between the 1950s–1990s which contain this material in the roof, and possibly also the walls of the property.

RAAC risks extend to private buildings

Recent news articles have highlighted concerns around RAAC, the presence of which has forced the closure of more than 100 schools in the UK. The material, which is a cheap and lightweight alternative to traditional concrete, was used in thousands of UK public buildings between the 1950s­–1990s, including schools, hospitals, and similar properties.

The problems with RAAC have been known since as early as the 1980s (opens a new window), when some buildings containing the material had to be demolished. It was in 1996 that the Government first alerted the public to issues with RAAC, when the Building Research Establishment (BRE) issued an information paper (opens a new window) that warned of “excessive deflections and cracking” in RAAC roof planks. Following the paper’s release, the use of RAAC was effectively discontinued.

There have been various other reports and articles since, highlighting that this problem is not just restricted to public buildings. These include a Cross Safety report (opens a new window) in February 2023, which references the presence of RAAC planks at a 1970s Shopping Centre. The report includes comments from an expert panel, stating that:

  • “When assessing or surveying existing buildings, engineers, architects, and surveyors should bear in mind that RAAC elements could have been used in roof and floors of many building types.”

  • “There is no reason why RAAC could not have been used in many other buildings, both public and private.”

The government issued guidance for identifying RAAC (opens a new window) in August 2023 for local authorities, academy trusts, governing bodies, schools and colleges, and building professionals.

Confirming the safety of RAAC buildings

Additional guidance (for all property owners and tenants to use) is available online from the Local Government website (opens a new window), and includes the below steps:

  • Ensure that the condition of all their buildings are regularly monitored, taking a risk-based approach that gives due deliberation to the use of the building with consideration given to the possible impact of reduced maintenance.

  • Ensure they have identified any RAAC property in their portfolio.

  • Ensure that RAAC properties are regularly inspected by a structural engineer including using a cover meter to check the provision of traverse and longitudinal reinforcement, note deflections, check the panels in the vicinity of the support, the width of the support bearing, cracking, water penetration and signs of reinforcement corrosion and any inconsistencies between panels. The frequency of subsequent inspections should be determined by the structural engineer conducting the initial inspection.

  • Adopt good roof maintenance practices:

    • Ensure water outlets are clear and are at such a level that allows free drainage of water from roof areas.

    • If the internal surface of the planks is to be decorated, use paint which allows moisture vapour to pass through it. Protect external surfaces with a coating which provides an effective barrier against the transmission of liquid water.

    • Where appropriate, reduce the dead load on roofs by removing chippings and replacing them with an appropriate solar reflecting coating

    • Ensure that all waterproof membranes are maintained in good condition

    • Keep records of deflections of RAAC planks and inspect the construction regularly.

  • Ensure that those responsible for the day-to-day management of any RAAC building:

    • Know that RAAC is used in the building and where it is used

    • Check regularly for visual signs of cracks, water penetration, deflection to soffits and ponding to roofs

    • Ensure that all staff know to report any cracks and or other identified potential defect issues

    • Are instructed to immediately close off any part of the building where cracks or other material defects appear pending further checks

Insurance implications

Where a building contains RAAC, it is likely that a survey would have previously brought this to the attention of a property owner. Speaking to a structural engineer or surveyor will help to establish if owners have any properties at high risk of containing this material. Checking whether properties were built in the relevant period of RAAC will provide further indication of whether those properties could contain RAAC.

Insurers may soon begin to ask questions at each policy renewal as to whether owners have any properties which may contain RAAC, although this has not yet started to happen. Where a building does contain RAAC, this is a material fact which must be disclosed to insurers as part of the fair presentation of risk. It is not yet clear what steps insurers may take where RAAC is disclosed as being present, but we would hope that each case will be treated on its own merits in relation to rates and cover. Insurers will likely insist that the safety of the property is properly monitored on a regular basis.

As we believe RAAC was not used after 1998 (opens a new window), there will be no cover under latent defects policies as these typically last 10–12 years maximum from practical completion, and all policies will have lapsed many years ago.

In their recent bulletin (opens a new window), entitled ‘Reinforced Autoclaved Aerated Concrete (RAAC) – concerns are growing over this widely used material’, McLarens have stated that:

  • “The presence of RAAC poses unique challenges in the context of insurance coverage. Building insurance policies may cover damage caused by sudden and unforeseen events. However, most policies are not designed to cover wear and tear or construction defects. If RAAC failure leads to sudden damage to other parts of the building, the policy may respond to the resultant damage only. Still, policy wording and exclusions will need to be carefully reviewed.”

If you have any questions, please contact your usual Lockton GREAC team who will be happy to assist you.

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