For those of you who are living on a remote island in the middle of the Pacific Ocean with no internet or access to mainstream media (MSM), there is a huge issue being reported on across the UK at present, it’s in every paper, on every channel and even being discussed in the local corner shops, that of RAAC (Reinforced Autoclaved Aerated Concrete).
“Now I’m no RAAC expert, in fact, up until a few weeks ago, my knowledge of RAAC was shall we say, very limited, bordering on weak…”
“…so why am I writing this and even more importantly, why are you reading it?”
RAAC was used to manufacture construction panels or “planks” that were used extensively in the building of many hundreds, if not thousands of buildings across the UK between the late 1950s up to the early 1990s.
RAAC, as the name would indicate, is a type of concrete that contains millions of tiny air pockets, thus reducing its weight significantly compared to that of normal concrete. Many news channels refer to RAAC as the “Aero”* chocolate bar of the concrete world, but for those of a certain age, think more “Wispa”¥, many more and much smaller holes.
The issue of this building component is that when installed, the product was estimated to have a life span of around 30 to 40 years. Given that we are now beyond this period, in some cases, 70+ years beyond, some of these panels are showing signs of fatigue and in some cases, they are failing, catastrophically.
Now ordinarily, a failing construction material wouldn’t normally be a major issue as the building it has been used in could be repaired, but when we're talking about potentially thousands of premises that are in constant, everyday use, it now becomes a major issue, especially given that the structures where RAAC was installed and used in, are, in the main, public and municipal buildings such schools, hospitals, and the like, which are buildings that when closed, present some rather urgent problems.
Now I’m no RAAC expert, in fact, up until a few weeks ago, my knowledge of RAAC was shall we say, very limited, bordering on weak. Yes, I’m familiar with this RAAC material having demolished many buildings over the last 30 years with it in, but when it comes to the current issue, I am at the mercy of the MSM, the internet and my own research, so why am I writing this and even more importantly, why are you reading it?
My area of expertise is asbestos, so I would ask again, Why am I writing this article? Could it be that RAAC could contain asbestos, NO, it doesn’t, however, the construction style and types of buildings where these planks were used, along with the period of use means that there is an unbelievable chance of encountering asbestos alongside or even in conjunction with the use of RAAC.
To give some idea of what I mean by this, back in the early 1950s, a consortium was formed in the UK with the aim of developing, designing, and building low-cost, quick-build structures due to a massive need to replace and build new schools, hospitals, civic buildings, etc. This consortium, referred to as the Consortium of Local Authorities Special Projects, (CLAPS) and later, SCoLA, the second Consortium of Local Authorities, were very successful in achieving its goal, so much so that the modular-style buildings they designed were adopted throughout the UK. Now not every CLASP or SCoLA structure incorporated RAAC, but many did, It must also be stated that due to its low cost, lightweight design and wide availability, RAAC was also used in non-modular structures!
Asbestos, as I'm sure many will know, was the miracle material of its time. Used in over 3000 known products, asbestos became the staple of building designers, architects and the construction industry in general. It was flexible, cheap, easy to work with and above all, fireproof, and here is where it comes into play with RAAC.
RAAC planks had one major benefit, besides being cheap, they could span long distances, sometimes, up to 4 metre spans. This meant that when forming a roof, the need for large amounts of supports or trusses to cover the span was reduced, resulting in a lower build cost and faster construction time. This also meant there was a limited need to form multiple structural walls to support the roof, thus creating larger rooms and areas.
One of the problems with these larger areas is that over time, as building uses changed, they were divided into the room sizes that were needed for the purpose of the building. This then created an open void above the walls in the ceiling void (more on this later).
These open voids required fire barriers to reduce and prevent the spread of smoke and flame through the building in the event of an incident, and you’ll never guess what material was used to form these barriers! Furthermore, the columns used to support the trusses on which the RAAC planks were supported were also in need of fire protection, again, asbestos was often the material of choice.
Asbestos Board (labelled red) cladding CLASP Column
In addition to these fire breaks and column claddings, many of the buildings used asbestos to form the suspended ceilings, and even where the ceilings were constructed of non-asbestos materials, quite often there would be debris or of-cuts from when asbestos was used, damage asbestos may also be present to the asbestos fire breaks caused during later cable and pipe upgrades and installs.
Images showing careless damage to asbestos boarding during cable installation
asbestos debris above a non-asbestos ceiling
asbestos shrouding around the roof skylight
Where skylights were introduced into the roof, it is often found that AIB was used as the infill panel.
So, why this article and why now?
As stated earlier, RAAC has become the talking point of 2023, especially where schools are involved. The need to ensure a healthy and safe environment for children, teachers and support staff must always be of paramount importance. Addressing the issue of these failing RAAC planks is a must, and an urgent one at that.
Many are calling for the full, national removal of all RAAC due to its age and potential to fail, and whilst I don’t disagree, we need to look at the wider picture. To remove many of these RAAC planks, first, the asbestos must be addressed.
Removing asbestos is no easy task, trust me, I've been doing it for over 3 decades, it's not cheap, and it is very time-consuming, and that’s if you know it's there!
To identify whether RAAC was used in any building, a survey is required, but before the RAAC survey, we need to ensure that the RAAC surveyor, and the premises occupiers, are safe. Before lifting ceiling tiles to look for RAAC, an asbestos survey may be required, or where one has been carried out, the asbestos register must be read and reviewed, that’s if there is a register!
Where asbestos is found/identified, it may require removal or some form of other work before anything else is done. It may also require removal where its location affects the RAAC works or even when just gaining access to assess the RAAC is required.
To remove the type of asbestos commonly used in these types of structures, typically Asbestos Insulating Board (AIB), it MUST ONLY be removed by an HSE-licensed asbestos removal contractor (LARC).
NOTE: other asbestos-containing materials may also be present.
Removing AIB is also subject to certain conditions, such as a 14-day pre-notification before any work involving its removal is carried out. Now a waiver for this can be applied for and I’m sure that if it was, it would be granted. This doesn’t however mean that this asbestos remediation work could start tomorrow, there's still a risk assessment to create, a plan of work to write, a workforce to find or re-assign, then the setup, the removal, and all this, potentially before we even get to the RAAC issue! We also need to ask, who’s paying for all of this?
Given that it is stated that thousands of all schools in the UK have some form of asbestos in them and that these schools are now approaching the end of their useful life, amny requiring replacement, some major refurbishment, I personally do not think that the issue with RAAC is the only one we will be seeing in the coming years with these buildings.
In an online article published by the Independent, the UK central government, I shall exclude names, stated that they would look to refurbish/build 200 new schools every year, but this was quickly reduced to 50…, the article goes on to state that last year, 4 new schools were refurbished in the UK, at this rate, it will be many decades before we see the end to issues in schools, and trust me, RAAC is only just the beginning.
As ever, I am open to debate and discussion on this and another article I present publicly. if my information is wrong, or even if you disagree with the content, let me know. My email and number are here and are available on my website.
Paul Beaumont
info@111cgl.co.uk
10/09/2023
*Aero is the registered brand name of Nestlé
¥ Wispa is the registered brand name of Cadbury, a product discontinued in 2003.
Several images used in this article are reproduced by kind permission and with the consent of the owner.