Liable to Collapse

Arianne Shahvisi

In 1897, the French archaeologist Jacques de Morgan pilfered the remains of the Apadana Palace (c.520 BCE) and the Elamite Chogha Zanbil ziggurat (c.1250 BCE) in Susa to build a castle for himself. The Château de Suse, whose construction was sponsored by the French government, became de Morgan’s base for exploring other sites in the area and a place to protect his trinkets from the locals whose heritage he’d pillaged. It stands on a hill above the modern Iranian city of Shush, the ancient Elamite inscriptions in some of its bricks announcing their appropriation.

While in Susa, de Morgan oversaw the excavation of a seven-foot basalt stele inscribed with the Code of Hammurabi, the best-preserved copy of one of the world’s oldest legal texts, drawn up by the sixth Amorite king of the Old Babylonian Empire. It is now on display in the Louvre, five thousand miles (and a great many political barriers) away from the sight of modern Iranians. The code, which lists 282 provisions and their punishments, is the first recorded example of the lex talionis principle, predating the Torah’s ‘eye for an eye’. It also lays out the earliest written building regulations:

229. If a builder build a house for someone, and does not construct it properly, and the house which he built fall in and kill its owner, then that builder shall be put to death.

232. If it ruin goods, he shall make compensation for all that has been ruined, and inasmuch as he did not construct properly this house which he built and it fell, he shall re-erect the house from his own means.

233. If a builder build a house for someone, even though he has not yet completed it; if then the walls seem toppling, the builder must make the walls solid from his own means.

Four thousand years later, along the spine of the Zagros mountains just north of Susa, my grandfather worked as a school building inspector from the 1950s to the 1980s. Farajollah Shahvisi travelled the perilous, slow-going roads that ribbon around the jagged, scrub-tufted peaks of Iranian Kurdistan, visiting schools with keeling walls and dripping roofs. There was a lot of theft. Builders would make off with government-issue cement, stuff gaps with debris and let bricks sit loose. A fault-finder by nature, my grandfather would close down schools and report cowboy developers, who’d be ordered to rebuild for free, much as Hammurabi decreed.

Over the same time period, hundreds of schools in the UK were topped with reinforced autoclaved aerated concrete. AAC is formed from a slurry of cement, gypsum and very fine sand or fly ash, to which powdered aluminium is added as a leavening agent. The aluminium reacts with lime and water to produce bubbles of hydrogen, leaving an evenly aerated crumb. Once cured at high pressure in an autoclave, the material has good compressive strength for its density but, like other forms of concrete, performs less well under tension, and is therefore commonly reinforced with rebar. Because of the increased risk of water ingress through all those holes, the panels and their steel bones are treated with a waterproof coat. The resulting material is light, robust, insulating, fireproof, mould-resistant – and cheap.

AAC looks like synthetic pumice, and has comparable porosity and density. Both will float on water for some time, sinking only when sodden. Pumice often drifts on the sea after the volcanic eruptions in which it is baked – it was believed in antiquity to be solidified sea foam, or spuma maris – and plant and animal species may have migrated from one island to the next on pumice rafts. Like RAAC, its airiness makes it a good choice for roofs. The thicker, lower strata of the dome of the Pantheon in Rome are speckled with marble-like travertine but the voussoirs near the oculus are thinner and lightened by pumice aggregate.

By the 1980s, RAAC planks installed in the 1950s and 1960s were beginning to fail. Bending and cracking in the concrete was leading to rebar corrosion. In some cases, the steel rods had always been too short, or weren’t properly anchored to the concrete. In reports published in 1996 and 2002, the Building Research Establishment gave RAAC a thirty-year design life and recommended inspections, maintenance and repairs. The material fell out of favour, but the existing planks were mostly left to the ravages of time and weather.

In 2018, a ceiling buckled into a classroom in an Essex primary school. It was a Saturday evening, so no one was hurt, but the empty desks and chairs were crushed under the rubble. Over the years since, a raft of structural surveys found that 572 schools were likely to contain precarious roofs, and in 2022 the Office of Government Property warned that ‘RAAC is now life-expired and liable to collapse.’ This summer, two ‘low-risk’ roofs caved into empty schools, prompting the current closures. Dozens of schools had their start of term delayed or turned to remote learning.

The education secretary, Gillian Keegan, seemed both surprised and peeved that the prospect of concrete falling on children’s heads would cause so much bother. She observed that ‘schools can collapse for many reasons,’ mithered that no one had told her ‘you’ve done a fucking good job,’ and breezily tweeted: ‘most schools unaffected’. (Keir Starmer’s press team live for this kind of low hanging fruit, and were quick with the obvious riposte: ‘most beachgoers not eaten by big shark’.)

Compared to her colleagues, it’s possible that Keegan has done a fucking good job. In 2010, Michael Gove scrapped Labour’s £55 billion ‘Building Schools for the Future’ programme, calling it ‘bureaucratic and wasteful’. Six years later, he described the decision as one of his ‘worst mistakes’, but the lesson wasn’t heeded elsewhere. When Rishi Sunak became chancellor in 2020 (after the first roof collapse in Essex) he cut the school rebuilding budget from £765 million to £560 million, and then to £416 million a year later. The Tories’ launched their own schools building programme in 2021, promising to complete five hundred schools in a decade, but managed only four in the last two years.

Keegan’s comments have an especially contemptuous ring when taken alongside her defence, in July, of private schools’ tax breaks:

Most of our private schools aren’t like Eton or Harrow – they’re far smaller and they charge a lot less. Many cost the same as a family holiday abroad and there’s plenty of parents who choose to forego life’s luxuries to give their children these opportunities . . . Labour’s tax hikes are nothing more than the politics of envy.

Bridget Phillipson, the shadow education secretary, pointed out that an average family holiday costs around £2000, while private school fees are about £16,000 a year for each child. (Eton and Harrow are more like £50,000 and they aren’t the most expensive: Brighton College costs £60,000, the equivalent of a family holiday for every week of school.) Many people who send their children to private school don’t sacrifice holidays to pay for it, and there are plenty of other people who can’t afford either.

Keegan’s diagnosis of a ‘politics of envy’ is off-key: envy, as Kant wrote, is a ‘propensity to view the well-being of others with distress, even though it does not detract from one’s own’. It isn’t envy to point out injustice. State schools struggle, structurally and otherwise, because they aren’t given enough public money; private schools prosper because they are well-resourced, excessively so, thanks to their charitable status. Ending this favour, as Labour are promising to do, would raise £1.6 billion a year. Private schools would ratchet up their fees, sending some students (whose parents can no longer afford nice holidays as well as an expensive education) into the state sector. Accounting for the additional cost of educating them leaves between £1.3 and 1.5 billion – three times what is usually set aside for fixing state school buildings.

A study published last January revealed the mechanism by which the concrete in the Pantheon is able to heal itself: when cracks form, lime clasts in the concrete – small white flecks formed from hot mixed quicklime – react with ambient moisture or precipitation to produce new crystals that can knit up the fracture within a couple of weeks. Given the many recipes for concrete on offer at the time, and the meticulous engineering of the temple, it is hard to believe that this property was accidental. It is harder to still to believe that two millennia later we’ve been putting children under roofs that fail after thirty years.


  • 18 September 2023 at 2:30am
    Graucho says:
    The most expensive sight you will ever behold is the Brits trying to save money.

  • 21 September 2023 at 1:18pm
    Shane Anderson says:
    Hi, Arianne, you've written a fascinating article on an important topical issue, many thanks. However, I feel the LRB has missed a trick in naming it, as Solidified Sea Foam has an elegant alliterative ring. Your final paragraph referring to the self-healing properties of Roman concrete is worth an article or book by itself. I will be sharing this with my students, so many thanks.

  • 22 September 2023 at 3:29am
    jcircosta says:
    In the US our politicians love to throw money at the Pentagon while our public schools rot. But then, all those thousands of students don’t vote & can’t send their very own lobbyists to DC. It is surprising to read that schools in the UK suffer too but not surprising that your equivalent to our Republican Party has other priorities. Here’s hoping no students in either country fall victim to this government failure. At least in the UK they are not apt to be gunned down.