There was recently a crisis in older publicly constructed buildings in the UK that were built [0].The aerated concrete had a limited lifespan especially if it was damaged and had contact with water.

Lots of people looking for compensation and claiming mis-representation.

[0] https://www.bbc.co.uk/news/education-66669239

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cornholio 4 hours ago | parent [-]

The UK crisis involved steel reinforced AAC beams that were used (of all places) to support roofs of schools. UK turned out to be a rainy place, the rain infused into the cellular structure and corroded the steel, with disastrous consequences.

It's a very particular use case of a very particular product, not relevant to the wide majority of AAC uses around the world, which is largely non-structural and not reinforced, or subjected to moderate compressive loads, such as lateral walls for 1-2 stories buildings in non-seismic areas.

	▲	gerdesj 42 minutes ago \| parent [-]
		The risks were understood (by engineers) and this usage was given a "shelf life". Unfortunately, those risks were put into the "Oh we'll forget about it" or "We'll wait until it looks a bit shifty" categories. However as any fule (engineer) kno, reinforced and especially pre-stressed conc members will fail in quite a dramatic fashion. Unless you notice rust dribbling out then you can end up with anything from the roof failing to the roof exploding. I don't think anyone was daft enough to pre-stress these things. I don't know how much money was saved but it was a really stupid application and basically ended up punting far greater costs due to remediation down the road.