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CROSS Safety Alert

Failure of reinforced autoclaved aerated concrete (RAAC) planks

Region: CROSS-UK, CROSS-AUS, CROSS-US Published: 1 May 2019


In late 2018, the Local Government Association (LGA) and the Department for Education (DfE) contacted all school building owners to draw attention to a recent failure involving a flat roof There was little warning of the sudden collapse.

It is believed that RAAC planks are present in many types of buildings. This Alert is to emphasise the potential risks from such construction, most of which dates back to between the 1960-80s. The useful life of such planks has been estimated to be around 30 years.

Note: this Safety Alert was published by SCOSS (Standing Committee on Structural Safety). Since March 2021, SCOSS is integrated under the name Collaborative Reporting for Safer Structures (CROSS).

Who should read this?

Owners of schools and similar buildings dating from the 1960-80s with flat roofs. Government departments and local authorities who have schools and similar buildings, National Health Trusts, dioceses/parishes, building surveyors, architects, civil and structural engineers, facilities managers.

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