A headteacher in a school affected by RAAC has said the Department for Education has shown a "lack of urgency" over dealing with the issue.

Cas Evans, the headteacher of Parks Primary School in Leicester, told BBC Breakfast the school had to relocate several classes and borrow rooms from other institutions in May after the discovery of RAAC.

Evans says the school has racked up around £30,000 in costs while organising alternative facilities, with the DfE saying "up until now" this would need to be covered by the school budget.

The DfE now says it will fund costs, external, though Evans says she has not been told this directly.

Speaking about the government's response to the issue, she adds: "There seems to be a lack of urgency. There are big questions that need to be answered."

The perception of risk from RAAC concrete in public buildings changed over the summer, the Conservative leader of Kent County Council has said.

Roger Gough acknowledged the timing of the school closures was "very last minute".

He told BBC Radio 4's Today Programme. "The timing is difficult for everyone affected.

"We know three things: Survey work by the Department for Education is quite wide-ranging but by no means complete.

"Second is the number of schools which are ultimately affected is relatively small and third is the perception of risk changes and that is what I believe we have seen recently."

An academy chief has said she was told by the Department for Education on Thursday to close school buildings with RAAC following a "policy change".

Sarah Skinner, the CEO of Penrose Learning Trust in Suffolk which controls eight schools, three of which are affected, told the Today programme the government first told her of the problem of RAAC concrete in her schools in July.

At the time, following DfE surveys, she said there were were suggestions of "remedial works".

But she says it was not until Thursday when she received a phone call that she was told there "had been a policy change" and affected school buildings had to close.

"We must have known about this earlier," she said.

"It is just very late in the day and that's what has created the problem to now find temporary accommodation, potential toilets, free school meals if our kitchens are out of action.

"There are things beyond classroom spaces which we have to consider."

Costs to fix the issue of RAAC in school buildings need to be met by the government, a funding specialist for the Association of School and College Leaders has said.

Julia Harnden tells BBC Breakfast school budgets are already "on a tightrope".

"Schools have been told there will be support from the government to help with the capital cost.

"We understand that could include putting in temporary classrooms. What we don't know are things like transport costs.

"Some parents have said schools will have to bus children - we still have a lot of questions about these things."

Hospitals have known about the problem of aerated concrete in its buildings for years, an NHS boss has said.

Matthew Taylor, CEO of the NHS Confederation, which represents health service organisations and their employees, told BBC Radio 4's Today programme: "We have known about this problem for a long time. There is a commitment to rebuild the hospitals which are entirely RAAC.

"The situations in those hospitals aren't great. Props are being used to ensure the safety of the buildings.

"It does have an impact - areas of those hospitals are not in use. Hospitals are fighting every day to tackle waiting lists - but I don't think anyone should worry they are at risk going into these buildings because work is being done to make them safe.

"The bigger issue is we have known about this for many years, but the hospital rebuilding programme has been delayed and delayed."

As we've been saying, it's not just schools that contain this crumbly concrete. It is known to be present in other public sector buildings, including healthcare settings and courts.

Opposition parties are calling on the government to urgently investigate the scale of the problem and be transparent with their findings.

Labour has called for an "urgent audit" to identify the risk of the concrete, while the Liberal Democrats say the public and NHS staff need "urgent clarity" over whether hospital wards and buildings face closures.

The Department of Health has reported 24 hospital sites with weak RAAC - seven of those are in line for full replacement, external.

Five separate NHS sites, like GP surgeries and care centres, have already had work done on RAAC, and another 34 sites are awaiting the results of checks.

There are seven court buildings that we know are affected too. But the problem is not just contained to the public sector. It could be in any buildings built in the 1960s and 70s.

But reaching people responsible for private building maintenance is more difficult than contacting those in the public sector, so we know even less about the scale of the issue there.

RAAC stands for reinforced autoclaved aerated concrete.

It’s a lightweight material that was used in the construction of roofs, floors and walls between the 1950s and 1990s.

It is a cheaper alternative to standard concrete, but because it is aerated, or "bubbly", it is less durable.

Moisture can seep in through those bubbles and weaken the material or rust the steel reinforcements within it.

We now know the lifespan to be around 30 years, and its structural behaviour is significantly different from traditional reinforced concrete.

It has been used in public buildings in the UK - including schools, hospitals, courts and police stations - though political parties are now calling for an audit into how widespread its use has been.

Image source, .

Image source, PA Media

On Thursday afternoon, just days before the start of the new school year, we heard that more than 100 schools had been ordered to shut buildings with a type of concrete known as RAAC. Yesterday we learned more about what prompted the move and identified some of the schools which are affected. Here’s what we know:

• At least 156 schools in England are affected so far. Of these, 52 had been deemed a critical risk and safety measures were already in place, and 104 were being contacted this week about getting them in place. It is unclear how many schools are having to fully close, but it could be as many as 24
• The urgent action being taken in England has triggered a search for RAAC in buildings in Scotland, Wales and Northern Ireland. Scotland has so far confirmed 35 schools are affected
• The Department for Education said it would fund works to remove any immediate risk, which could include the cost of temporary buildings
• The urgent call for schools to close buildings with RAAC was triggered by a concrete beam collapsing over the summer. It had previously showed no sign of being unsafe
• Other public buildings - including courts and hospitals - were also constructed using RAAC, and many of those are also in need of remedial work or repair

Alex Therrien
Live reporter

Good morning.

Ministers are facing schools for transparency over the scale of aerated concrete in public buildings after schools were forced to shut classes days before the new term begins.

More than 100 schools across England have been told to immediately cordon off buildings that have reinforced autoclaved aerated concrete (RAAC) - a type of concrete that has a lifespan of around 30 years.

But the "crumbly" concrete is also thought to be present in other public buildings, including healthcare settings and courts. Opposition parties are calling for more information about the scale of the issue, and Labour is calling for an urgent audit.

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