RAAC Advisory Notice
- Thu, September 12, 2024
- by rcs-admin
Guidance for Building Owners, Duty Holders, Accountable persons, Principal Accountable Persons, Block Managers, and Landlords
Issued by: RCS
Date: 01/05/24
RCS (RAAC Consulting and Solutions) is a consortium of engineering scientists, surveyors, structural engineers, construction experts and industry leaders. Together, we have unique insight into the science of RAAC, the risk it poses to buildings and how to work through the practical and logistical challenges faced by organisations.
Executive Summary
It is clear from the level of safety alerts, guidance issued, and industry commentary that RAAC is a pressing problem that needs to be addressed. RAAC is being found in numerous settings and many outside the “typical range”. A significant liability exists for building owners and operators who are unaware of the presence of RAAC within their buildings /portfolio.
Introduction
This document serves to inform all building owners, managers, and landlords of the crucial need to assess the presence and condition of Reinforced Autoclaved Aerated Concrete (RAAC) in their structures.
RAAC has been prevalent in the news over the past twelve months with many schools, hospitals, courts and other government buildings, finding RAAC in their structures. As an industry, the understanding of where RAAC was used is evolving. What is clear is that the UK government is not comfortable with the risk of unknown RAAC within the government estate.
A recent presentation by government sponsored research agents (The Manufacturing Technology Centre) suggests that between 1.5-4.5m RAAC panels were sold in the UK between 1950-1998. They estimate that approximately a third of panels have been found. It is their assumption that a very significant proportion of the balance exists within privately owned buildings.
Understanding RAAC
What is RAAC?
Reinforced Autoclaved Aerated Concrete (RAAC) is a lightweight, aerated form of concrete that was popular in construction from the 1950s to the early 1990s, particularly in the United Kingdom. RAAC is made by adding aluminium powder to the cement mixture, which causes the concrete to form microscopic gas bubbles as it cures, significantly reducing its density compared to traditional concrete.
This material was favoured for its insulative properties, light weight, and ease of production and use in large panels or blocks. However, RAAC has significant drawbacks that have led to concerns over its use in buildings, especially as it ages. The material is less durable and has a shorter lifespan compared to traditional concrete. Over time, RAAC can suffer from structural deficiencies such as cracking, excessive deflection, and corrosion of embedded reinforcement, which may not be visible until failure is imminent. These issues pose potentially significant safety risks, particularly in older buildings where RAAC was used extensively in structural components like roof planks and wall panels. As a result, there is an ongoing need for assessment and remediation in buildings containing RAAC to prevent potential structural failures.
For more information, you can find an expert explainer from Professor Chris Goodier on the Loughborough University website.
Where is RAAC?
The picture of where RAAC was used is constantly evolving. The media have tended to highlight the issues in schools and hospitals; however, this coverage, along with increased scrutiny from regulatory bodies, has led stakeholders to commission surveys in other settings. This has led to the discovery of RAAC in a wide range of buildings, and this is expected to increase as more surveys are conducted. The settings in which it has been found to date include,
A wide range of local authority infrastructure:
- Theatres
- Courts
- Prisons
- Social housing
- Commercial/industrial complexes including shopping centres
- Housing estates, including those publicised in Aberdeen and Basildon
- Ex Council properties and privately owned homes
- Extensions and additions to buildings pre-dating the 1950’s
Key risk factors
When the initial alarm associated with RAAC happened in September 2023, following the sudden collapse of some school roofs and corresponding closure of many schools, guidance was issued asking building owners to review buildings constructed between 1950-1990. Subsequently, this guidance has been found to be insufficient and RAAC has been discovered in numerous settings outside of this range.
The main criteria associated with the presence of RAAC, are as follows:
- Buildings constructed between 1950-1998 Safety Notice 1998
- Flat roofs
- Flat roof with evidence of ponding or standing water
- History of spalling material
However, although RAAC was thought to be used in flat roofs, numerous examples of pitched roofs using RAAC have now been discovered. Pitched Roofs Alert. RCS can also confirm it has been commissioned to work on RAAC affected buildings with pitched roofs including grade 2 listed properties.
As well as the key risk, it is important to note that RAAC appears to have been used for additions, repairs and infills to older buildings. For example, a building from c1780 has been found with RAAC. Historic Buildings RAAC.
Frustratingly, no register exists of known RAAC, so the true extent of its use is unknown and new settings are being discovered regularly. What is clear is the risk sits with the duty holders.
What guidance has been issued?
Numerous bodies have issued guidance on the subject of RAAC, and below are links to several of the key documents produced to date.
Health and Safety Executive (HSE) Guidance on RAAC: Comprehensive guidelines are available on the HSE website.
Confidential Reporting on Structural Safety (CROSS): Refer to CROSS reports for documented incidents and expert recommendations on the Cross Safety website.
The Institution of Structural Engineers: information on Reinforced Autoclaved Aerated Concrete (RAAC) on istructe.org.
From the Local Government Association Office of Government Property: RAAC Safety Briefing Notice and Information on Reinforced Autoclaved Aerated Concrete (RAAC) on local.gov.uk
For England: Department for Education collection on reinforced autoclaved aerated concrete in education settings including Reinforced autoclaved aerated concrete: guidance for responsible bodies and education settings with confirmed RAAC and Reinforced autoclaved aerated concrete: identification guidance.
For Scotland: Local authorities publish RAAC data and Reinforced Autoclaved Aerated Concrete (RAAC): Parliamentary statement
Parliament Guidance for RAAC in privately owned buildings: The government has said that individual building owners and managers are responsible for “responding to safety alerts such as RAAC”. Building owners and managers have responsibilities under different pieces of legislation, including the Defective Premises Act 1972 and Occupiers’ Liability Act 1957, for the maintenance of their buildings’ structure and the safety of employees, tenants, and members of the public.
Fire Brigade: https://www.london-fire.gov.uk/safety/property-management/reinforced-autoclaved-aerated-concrete-raac-advice/
Church of England: https://www.churchofengland.org/resources/churchcare/advice-and-guidance-church-buildings/reinforced-autoclaved-aerated-concrete
Royal Institute of Chartered Surveyors (RICS):
https://ww3.rics.org/uk/en/journals/built-environment-journal/locating-raac-reinforced-autoclaved-aerated-concrete.html
Legal and Regulatory Framework
In this context, there are four highly important statements for building owners to note:
HSE guidance states “Owners or managers of these buildings should identify reinforced autoclaved aerated concrete (RAAC) in their buildings and seek specialist advice to assess it and develop a management plan.”
Legal opinion (Top 100 Law Firm, advising in the construction sector) “The risk of collapse caused by RAAC is highly likely to constitute a breach of the 1974 Act and, were a collapse to lead to a fatality, depending on the facts, there is the potential for corporate manslaughter charges” Full article
Defective Premises Act:
Building owners have a legal duty to ensure their properties are safe for residents and visitors. This includes regular inspections and maintenance to prevent defects.
Building Safety Act:
Recent updates mandate stringent compliance to safety standards, particularly relating to materials like RAAC. Non-compliance can result in heavy penalties.
Safety Risk Regulations and the Golden Thread.
Insurance and Commercial Perspectives
Insurance Coverage:
Insurance considerations for buildings with Reinforced Autoclaved Aerated Concrete (RAAC) present unique challenges, particularly because RAAC is not typically covered by standard insurance policies due to its classification as a construction defect, or wear and tear issue. Here’s a summary of the pertinent insights from various sources:
- Disclosure Requirements: Property owners are strongly advised to disclose the presence of RAAC to their insurers as part of a fair presentation of risk. Failure to disclose could impact the validity of a policy, especially if RAAC presence is a material fact that could influence the insurer’s decision to underwrite the risk (Lockton) (UKGI Insight).
- Policy Coverage and Exclusions: Insurance policies generally cover damages from sudden and unforeseen events. However, damage caused by RAAC, due to its nature as a known defect with a limited lifespan, may not be covered unless it leads to sudden and unexpected damage to other parts of the building. This would necessitate a careful review of the policy wording and exclusions to determine the scope of coverage (Lockton) (UKGI Insight).
- Latent Defects Policies: Buildings constructed with RAAC after its last known use in 1998 would not be covered under latent defects insurance, as these policies usually expire 10-12 years after completion, and all such policies would have lapsed long ago. This implies that newer buildings are unlikely to be affected by RAAC-related issues (The Midlands Business Network).
- Risk Management and Regular Monitoring: Given the potential risks associated with RAAC, insurers may require property owners to undertake regular monitoring and maintenance of buildings containing RAAC. This could include structural inspections and adopting good maintenance practices to mitigate the risks of collapse or other structural failures (Lockton).
- Consulting Professionals: Property owners are encouraged to consult structural engineers or surveyors to assess the presence and condition of RAAC in their buildings. This professional advice is crucial in managing risks and ensuring that all safety measures are in place (Lockton) (The Midlands Business Network).
In summary, managing the insurance implications of RAAC involves understanding the exclusions and conditions of building insurance policies, regularly monitoring and maintaining properties, and ensuring full disclosure to insurance providers to manage liabilities effectively.
Risk Management:
Regular risk assessments and updates to insurance coverage are recommended to mitigate potential financial liabilities.
Managing RAAC Risk
Many building owners have not identified the potential risk of RAAC within the properties they own or manage. “It’s not a flat roof” or “ it’s too old” are common and misplaced complacencies. What is clear is that enough guidance has been issued to put the risk firmly in the owners, or building managers, hands. Naivety at this point will not be a defence, and various legislation will be applied in the event of a catastrophic event. Although these events are rare, they have been shown to be possible both in terms of evidenced events, and the research conducted by Loughborough University. The challenging part of RAAC is that shear failure can be sudden, and without clear indication before it happens. In order to manage effectively the inherent risk within a building or a portfolio, a risk assessment and survey will be required.
Identification:
Survey your properties to identify the presence of RAAC; this should be undertaken by a RAAC specialist rather than a surveyor in general practice.
Risk Assessment:
Structurally assess the condition of RAAC components. Again, this should be conducted by a RAAC specialist structural engineer.
Remediation:
Implement appropriate remedial action or a monitoring protocol. There are various options available and, therefore, an assessment to determine the best fit and best value for money option is very important.
Conclusion
We urge all property stakeholders to take immediate steps to determine if they have RAAC present in their buildings. And, if so, to seek specialist guidance as to the best course of action to assess and, if necessary, to remediate it.
Proactivity is essential to ensure the safety of all occupants, and the long-term viability of your property investment.
For further information or assistance, please contact RCS. We work with owners and managers to help identify risk in the portfolio as well as efficiently conduct surveys, structural assessments, mitigation options and remediation – if necessary.
Please contact us at https://rcs-services.co.uk/contact-us/
