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Reinforced Autoclaved Aerated Concrete planks (RAACs)

Reinforced autoclaved aerated concrete (RAAC) is a form of lightweight concrete sometimes referred to as panels. It was used primarily in roof planks of some public buildings built between the mid-1960s and mid-1990s.

Why this group was formed

Recently there have been a few failures in these planks/panels, which has led to an alert from SCOSS and reports of failures to CROSS.

This study group is open to all to provide a place for information and guidance on RAAC. You do not need to be a member of the Institution in order to join the study group.

Join the group to receive updates

The Institution has created a list of professionally registered structural engineers (Chartered or Associate-Members) who have experience of providing solutions for managing RAAC planks.

The following are suggested steps that building owners/ managers who are responsible for the safety of buildings should follow. This will enable building owners/ managers to address any issues relating to reinforced autoclaved aerated concrete (RAAC) that may be present in their structures:

  1. Identification – Not all buildings built between 1960 to mid 90s will have RAAC. It is therefore important to establish if they are present in your building. Identification can be undertaken by an experienced estate/ maintenance manager/ or building owner. A guide has been created to enable managers of educational buildings to identify if their buildings have RAAC. However, if you are unsure then you can contact a professionally registered structural engineer or surveyor to identify if RAAC are present. To note they do not need to be an expert in RAAC to identify if the building has RAAC

  2. Assessment – Once you have established that RAAC has been used, your building will need to be assessed to understand what, if any, risk there is and if any immediate temporary remedial work is required. The Institution has established a list of professionally registered structural engineers who have experience of RAAC and are able to assess your building

  3. Solutions - competent structural engineers will need to evaluate all the information (which will include a detailed site inspection) and propose the remedial works to be completed. The list of professionally registered structural engineers who have experience of RAAC can be accessed below

Members with RAAC experience

List of professionally registered structural engineers who are able to undertake steps 2 and 3 are listed below:



Rob Cargill
Skanska Technology
Maple Cross House
Denham Way
Maple Cross
E: [email protected]
021068090 Member
Martin Liddell
MLM Consulting Engineers
North Kiln, Felaw Maltings
46 Felaw Street
UK - England
T: 01473 231100
020272042 Member
Stewart Macartney
Blyth & Blyth Consulting Engineers
60 South Gyle Crescent
EH12 9EB
UK - Scotland
E: [email protected]
01026758X Fellow
Matthew Palmer
62-64 Hills Road
UK - England
T: 07876 817 281
E: [email protected]
018361722 Fellow

Get involved - For structural engineers wanting to be added to the list

In order to be considered for inclusion on the list of structural engineers with experience of RAAC you must meet the following criteria and submit a short CV, including your IStructE membership number, to [email protected].

  1. Be a professionally registered structural engineer with the Institution (Chartered or Associate-Member)
  2. Demonstrate, through your CV, experience of working with RAAC including the assessment and proposal of solutions
  3. Agree to sign up to the free CROSS UK mailing list

Join the list

Additional resources

Local Government Association - Information on Reinforced Autoclaved Aerated Concrete (RAAC)
CROSS Report 908 -  Failure of RAAC planks in schools
You can confidentially share your experiences on RAAC planks with CROSS

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