Reinforced autoclaved aerated concrete (RAAC) in Scotland's schools could be a serious risk to pupils – Alex Cole-Hamilton

The Scottish Government must act quickly to make sure school buildings are safe

After my Grandpa left the Navy, he went into the construction industry. It was a booming sector considering the devastation the war had brought to British towns and cities but, in comparison to how things are today, it was a profession that was largely unregulated.

He would, from time to time, regale us with scare stories about buildings that he would never dream of going into because he knew that the rival firm which had built them had cut several corners, like failing to insert the reinforcing bars into load-bearing ‘reinforced’ concrete piling. I should stress, he would always report these concerns.

It was a simpler and fairly lawless time in the building trade and, as with asbestos, a greater understanding of engineering and public safety has left it to our generation to pick up the pieces, in some cases quite literally. That growing understanding has revealed a new threat to building safety in the form of a building material that could cost hundreds of millions of pounds to make safe.

Reinforced autoclaved aerated concrete (RAAC) is a light, bubbly form of precast concrete, frequently used in UK public sector buildings from the mid-1950s to the mid-1990s. Imagine the inside of an aero chocolate bar and you get the idea. Alarm bells started ringing about this with the collapse of a school roof in Kent in 2018. Thankfully it happened outside school hours, so no one was hurt.

The Department for Education recently warned RAAC panels “increase the risk of structural failure, which can be gradual or sudden with no warning” and "sudden failure of RAAC panels in roofs, eaves, floors, walls and cladding systems would be dangerous and the consequences serious". The Ministry of Defence’s Defence Infrastructure Organisation has issued a warning, noting that RAAC has a low compressive strength, around 10-20 per cent of traditional concrete, and is at risk of water damage.

So where is this stuff being used in Scotland and how widespread is the risk? Freedom of information research conducted by Scottish Liberal Democrats revealed that at least 37 Scottish schools are using this form of concrete, including nine in Dumfries & Galloway, seven in Aberdeen, six in Clackmannanshire and five in West Lothian.

We know of other schools in the North East and at least one in East Lothian that have confirmed the use of aerated concrete in their buildings. But this could just be the tip of the iceberg, given that investigations are ongoing in Edinburgh, Aberdeenshire, Falkirk, North Ayrshire and North Lanarkshire.

Preston Lodge High School in East Lothian has closed off more than 20 rooms following the discovery of 'reinforced autoclaved aerated concrete' (RAAC)

We need the Scottish Government to get to grips with this and fast. They need to work with education authorities to identify problem sites immediately and offer them the funding to make things safe. Because, while concerns about the use of RAAC have been in the public domain for years, many schools still don’t know if this is what is holding up their roofs. And, given the warnings from the Department of Education in England, Scottish parents will want to know that their children will be safe when they go to school.

Like with the removal of asbestos, this will be a painstaking and time-consuming process, but it is a necessary one. An unwelcome hangover from the past.

Alex Cole-Hamilton is Scottish Liberal Democrat MSP for Edinburgh Western