Since the closure of various schools prior to students' return to studies this September, there has been an increased awareness of RAAC (or reinforced autoclaved aerated concrete). Issues relating to failing RAAC could affect public sector buildings and structures, such as schools, hospitals and prisons and also those in the private sector such as offices.

The impacts across the construction sector, in its widest sense, are not yet known – but what is clear is that hundreds of buildings and structures and thousands of people across the UK are affected, that immediate bridging solutions are vital and that longer term there needs to be more detailed remediation (or rebuilding) and money found to pay for it.

RAAC and construction

In short, RAAC is a lightweight, bubbly building material which was used between the 1950s and mid-1990s and it has a lifespan of 30 years (meaning that it will be approaching the end of its lifespan). Its popularity was due to it being a cheaper alternative to concrete, as well as being quicker and easier to produce and install. RAAC was used primarily in flat roofing, walls and floors.

The risks of RAAC as a building material were first identified in the 1980s, as earlier buildings constructed showed signs of defects and it became apparent that RAAC's bubbled texture resulted in it being more susceptible to structural failure when poorly maintained and continually exposed to moisture or polluted air. It is particularly concerning that when RAAC fails, there is a high risk of structural collapse with little or no warning.

Key steps if your building may have RAAC

What you should do if you think that your building or structure may contain RAAC will depend on a number of factors, including where you believe it might be, how that area is used, and the particular risks to the safety of people or the structure itself. However, some key steps to consider, including on potential claims, are below.

  1. Check your contracts

Given the risk of building collapse posed by deteriorated RAAC, protective and remediation works should be a priority for those responsible for affected buildings.

Building owners, landlords, tenants, employers and other entities may all have obligations in relation to repair work on affected buildings. So check your contracts (including leases) carefully to ascertain who is responsible for such works. Seek legal advice if you are unsure of your obligations.

  1. Survey your buildings

Any building which may contain RAAC should be surveyed by an appropriately qualified expert as soon as possible and a risk assessment should be carried out on any RAAC found. This will help to put a short-term action and long-term remediation plan in place and to assess the cost of remedial works.

  1. Consider a claim

If you are responsible for repairing your building it is worth thinking about whether you may be able to pass that liability on to or reclaim the costs from someone else, for example the original building contractor. However, as things stand it is not clear that the use of RAAC and RAAC as a product itself is defective. Rather, it would appear that the product has reached the end of its intended lifespan. This means that no one may be at fault for its use in your building. This position, however, remains under review.

  1. Check limitation periods

Even if it is established that liability for the use of RAAC in your building can be placed with another, the default position under the Limitation Act 1980 is that a claimant has six or twelve years to bring a claim (depending on whether the contract was signed under hand or as a deed). The date is typically calculated from the date practical completion, so it will be important to have this information.

Given the time period in which RAAC was used – between the 1950s and 1990s - it will likely be the case that a claim is well out of the limitation period, and that therefore a claim will be well out of time.

  1. Different limitation for residential buildings?

For potential claims relating to buildings with residential elements, there is a chance that this may fall within the remit of the Building Safety Act 2022 (BSA), which provides for a retrospective 30 year limitation period for claims brought under section 1 of the Defective Premises Act 1972 (DPA).

In addition, section 1 of the DPA places a duty on contractors to see that dwellings built are 'fit for habitation' at the time of completion. Given that RAAC was until the last 10 years thought safe, an argument of this type will be difficult to pursue, but further guidance on its use is awaited.

  1. Check if there have been subsequent repair works

If there have been subsequent repair works to the building (regardless of whether it is residential or not), the contractor carrying out the repair works may have assumed responsibility for the RAAC, or for the structural integrity of the building. In this case, claims may be brought within the limitation period, depending upon when the repair works were carried out.

What next?

The position on RAAC is fast moving. What we know so far is that it is imperative for those responsible for buildings and structures to properly check these to assess whether RAAC is present and if so, whether it is at risk of failure.

The likelihood of bringing a claim currently look slim but nonetheless you should check all of your contractual documents to be certain if this is the case, as the costs of remediation may well be high.