Remediate and collaborate: Addressing RAAC’s future

In June 2023, the UK government launched an inquiry into the use of crumbling concrete in public buildings, following fears that nurseries, offices, shops and leisure facilities were in danger of collapse. Attention was most pertinently drawn to the educational sector, with 231 schools and colleges identified as containing the crumbling material in November 2023.

In the months that have followed, the breadth of the construction supply chain has been called upon to provide surveys, maintenance and engineering solutions that will ensure the longevity of buildings affected. To complete this work effectively, consultants like us have been analysing the cause and effect of RAAC’s implementation, and the key takeaway is we must work collectively and collaboratively.

Assessment is an ongoing process

One of the primary challenges in solving the RAAC crisis has been its widespread use. Commonly found on flat roofs, the material was deemed a cheaper and faster to install method than traditional concrete in the 1950s and 60s. Its then lauded versatility also saw it used in pitched roofs, floors and walls, making future inspection a multi-faceted pathway.

Deterioration, with moisture appearing in the aerated structure, has in many cases occurred over time, meaning survey work to correct and identify failure is not a straightforward task, particularly without intrusive methods. It’s one of the key reasons consultants like Pick Everard have worked to a comprehensive RAAC risk assessment plan. Following a traffic light system, the plan works to a structured inspection period, from annual to a three-year review, depending on the severity of risk. Anything deemed ‘critical’ or ‘high risk’ is subject to immediate remedial works, including strengthening and replacement works.

We’ve recently put this into action at the 400-seat Key Theatre in Peterborough, when RAAC was found in the theatre last September, causing it to close just ahead of panto season.

A plan was immediately mobilised to design a secondary roof system underneath the existing roof inside the main auditorium, showcasing how a timber design, using a quick, local supply chain, can act as a temporary solution to the problems encountered. Thanks to our survey and design work, the panto went ahead as planned in December, with Peterborough City Council looking for a more permanent solution later this year.

Look to long term strategy

As experienced building surveyors and structural engineers, we understand that any RAAC management strategy must deliver long-term confidence. This is especially important given the issue has had a lack of focus and review up until the most recent crisis.

Contingency plans must be put in place to counter any of the future effects of low to medium risk areas that will, at some point in the risk process, be repaired or replaced. All building occupants, including key stakeholders, should also be aware of all works carried out, both during and after remediation work, to ensure a working knowledge of the building is carried forth into the future.

It is also important that remediation works must also account for the presence of asbestos, with the mineral thought to be in 80% of state schools nationwide. The dual presence of asbestos and RAAC proposes a highly dangerous situation, given a roof collapse could release asbestos fibres into the air.

We support clients with this long-term planning and strategy, delivering feasibility studies for future works and developing long-term relationships with local authorities that ensure trust and confidence in their public estates.

Knowledge is power

Last April, the Institution of Structural Engineers (IStructE) published supporting guidance to help with the assessment of RAAC panels.

It covered a number of areas, including water penetration, stress movements and structural integrity. It is important as an industry that we absorb and build best practice from these materials, including the government’s official guidance, to ensure RAAC can be a topic that, while in the public discourse, is spoken of positively and solution-fronted, rather than the damning reports that have plagued its past.

Pick Everard is committed to strengthening identification, assessment and remediation of RAAC, undertaking key projects like the Key Theatre in Peterborough to ensure a safe and risk free future for our public estates.

To understand further our expertise, head to our services page or contact us today.