In December 2018, the Department for Education (DfE) and the Local Government Association (LGA) made building owners aware of a recent building component failure in a property constructed using RAAC. In May 2019, the Standing Committee on Structural Safety (SCOSS) raised an alert to emphasise the potential risks from such construction, highlighting the failure of a RAAC panel roof construction within an operational school. This collapse was sudden with no apparent warning. Since then, we have been made aware of further sudden collapses of RAAC panels in roofs that appeared to be in good condition. It is therefore essential that all responsible bodies undertake work to identify any RAAC they have in their estate following the stages set out in this guidance. Prior to this, in the 1990s, there had been other concerns raised relating to structural deficiencies in RAAC by both the Building Research Establishment and SCOSS. It was recognised that the in-service performance was poor with cracking, excessive displacements and durability all being raised as concerns.
RAAC panels are most commonly found on flat roofs, they may also be found in pitched roofs, floors or walls
RAAC panels are light-grey or white in appearance, the underside of the panels will appear smooth. The inside of the planks will appear bubbly, often described as looking like an Aero bar. Unlike traditional concrete, there will not be visible stones (aggregate) in the panels
If you have drawings from the time the building was built or modified, you should review these. Common manufactures of RAAC panels are Siporex, Durox, Celcon, Hebel and Ytong.
RAAC panels are typically 600mm (approximately 2 feet) wide although this has been known to vary. Their length will vary, typically up to 6 metres. RAAC panels typically have a chamfer along their edge meaning there is a distinctive V-shaped groove every 600mm in the surface of the roof, floor or wall.
RAAC panels are very soft. If you press a screwdriver, screw or nail into the surface of a RAAC panel you will be able to make an indentation in them. BE AWARE – if there is a surface covering to the panels you should not try to make an indentation as the covering may contain asbestos.
RAAC panels may bow or deflect. From the undersize of the roof or floor you may see a ‘gap’ between two adjacent panels.
Please see this official government RAAC Identification Guide document, for more information.
If you require our services, or have any questions regarding RAAC, please don’t hesitate to contact us.