Alongside the recent news of school closures in England, the use of Reinforced Autoclaved Aerated Concrete (RAAC) in public buildings has also triggered concern in Scotland, Wales and Northern Ireland.

Here is what we know so far about the situation in the devolved nations.

Scotland

• The Scottish Government says it is trying to establish how many schools contain RAAC
• A full report on how many schools are affected is expected "in the coming days"
• More than 250 NHS buildings could contain the faulty concrete, it was revealed in July

Wales

• A construction expert says that RAAC has likely been used in a range of public buildings in Wales
• So far, there have been no reports of RAAC being present in any schools, college or nurseries
• In August, hospital patients had to be moved from Withybush Hospital in Haverfordwest after RAAC was discovered in the building

Northern Ireland

• Schools are being checked for RAAC as a matter of urgency, according to the NI Department of Education

The government will have to find the money to pay for the repairs needed on public buildings containing RAAC, according to Labour MP Clive Betts, who is also the chair of the Levelling Up, Housing and Communities Committee.

Speaking to the World at One programme on BBC Radio 4, he suggested local authorities may not have the money to cover the costs as they "have had bigger cuts to their budgets than any other part of the public sector since 2010".

He also called for further investigations into whether RAAC is in other public buildings, such as houses and hospitals.

"There's obviously got to be serious investigations now into hospitals, into other government buildings like courts. But also into the housing stock.

"We don't know where this concrete's been used in the past."

We've been answering your questions about RAAC for the past hour or so.

But we still have plenty of questions of our own, and we're working hard to try and get you the answers.

Here's a flavour of them...

We don't know which schools have confirmed RAAC. The government says it will publish a list but hasn't said when.

In the meantime, we've been trying to find out directly from schools - and we're keeping our own list here.

The absence of a full list means we're also not sure how many schools are having to close - fully or partially - as a result of the government's new guidance yesterday. We think it could be as many as 24.

And we still don't know how many schools across the UK have RAAC.

Although 156 have been confirmed to have it in England, that number could go up as more surveys are carried out, and we don't yet have confirmation of numbers in Scotland, Wales and Northern Ireland.

Then there are questions about timings - how long will temporary safety measures be in place for, and when will the RAAC itself be removed and replaced?

The scale of the problem will differ from school to school - in some cases it could just be one small room affected, in others entire buildings - so the timings involved will also vary.

Thanks to all of you who sent in questions on the school concrete problems - and many thanks to Professor Chris Goodier from Loughborough University, the BBC's education correspondent Hazel Shearing, and our digital lead for education news Alice Evans for answering them.

Stay with us for the latest updates throughout the day.

Will more schools have to close?published at 14:49 British Summer Time 1 September 2023

14:49 BST 1 September 2023

Alice Evans
Digital lead, BBC News education team

"Worried parent” Ray Chester, asks: a) if more work is going on to find other schools in this position, and b) whether the DfE can confirm no more schools will have to close.

The short answers are a) yes, and b) no.

The DfE hasn’t given specific numbers of schools that need to close as a result of yesterday’s announcement.

Schools with RAAC only have to close or partially close if they do not have safety measures in place, and cannot make alternative arrangements – such as converting other parts of the building into temporary classrooms or moving children to another site.

A total of 156 schools have confirmed RAAC. Of those, 52 have already put safety measures in place. The other 104 are currently scrambling to put safety measures in place to stay open - we think as many as 24 of them may have to fully close.

But hundreds more schools are yet to conclude whether or not they have RAAC. Back in June, a report by the National Audit Office assessed that 572 schools had been identified where RAAC might be present.

Is there RAAC in swimming pools?published at 14:44 British Summer Time 1 September 2023

14:44 BST 1 September 2023

Chris Goodier
Professor of construction engineering and materials, Loughborough University

Brian Gaines has been in touch to ask: It is understood RAAC is more prone to failure where exposed to chlorine rich atmospheres such as enclosed swimming pools, have any related incidents been reported?

I’m not aware of any cases of RAAC in swimming pools, but there might be.

Why is the guidance different in Scotland?published at 14:40 British Summer Time 1 September 2023

14:40 BST 1 September 2023

Hazel Shearing
Education correspondent

Amanda Elvines asks: "Why is the guidance different to Scotland? RAAC has been identified in my children’s school here in Nairn but we are repeatedly told it’s fine."

The change of guidance yesterday applies to England only. We don't yet have a full picture of the situation in the rest of the UK.

Scotland has already started to inspect RAAC in its school buildings, and a full report on how many schools in Scotland are affected is due to be delivered to the government soon.

According to the Liberal Democrats, RAAC was found in at least 37 schools in Scotland.

The Welsh government has said it will survey the country's schools and colleges to check if any are made with RAAC. In Northern Ireland, surveys are under way.

The reason it's different depending on where you live is because education is run by devolved governments in each nation.

So we've heard from Education Secretary Gillian Keegan and Schools Minister Nick Gibb over the past 24 hours, for example - but they are only in charge of education matters in England.

It seems likely that we could hear more from other devolved governments in the coming days.

What is a 'non-school'?published at 14:35 British Summer Time 1 September 2023

14:35 BST 1 September 2023

Alice Evans
Digital lead, BBC News education team

Siobhan Eccles asks: "What is a non-school?"

This question presumably relates to what Schools Minister Nick Gibb said earlier today: "What we discovered over the summer was a number of instances, in schools and in non-schools, in England and outside England, where RAAC that had been considered to be a low risk actually turned out to be unsafe.”

I reckon “non-schools” means other buildings used for educational purposes, such as nurseries, but also buildings used for other things.

Lots of other public buildings have been identified as being at risk because of RAAC, including courts, hospitals and police stations.

Could affected buildings be re-purposed?published at 14:28 British Summer Time 1 September 2023

14:28 BST 1 September 2023

Chris Goodier
Professor of construction engineering and materials, Loughborough University

We've had a question from someone who didn't leave their name asking if the affected buildings could be re-purposed?

Some can be.

For some it would be economic to replace the whole roof and for some to strengthen the roof.

But for some, it may be necessary to simply demolish the whole building and build a new structure.

A case by case assessment is required.

What percentage of the schools affected are academies?published at 14:22 British Summer Time 1 September 2023

14:22 BST 1 September 2023

Hazel Shearing
Education correspondent

Claire Simmons asks: "Is there any way of finding out what percentage of these schools are academies, rather than local authority maintained?"

The only way we could know that is when the government publishes its list of 156 schools that have been confirmed as having RAAC present. It hasn't done that yet, but says it will.

Individual schools will be contacting parents about any alternative arrangements, although some families may not have heard yet.

Shadow education secretary Bridget Phillipson said Labour had not seen the full list of schools affected, and called on the government to make it public.

She urged ministers to "come clean with parents and set out the full scale of the challenge that we're facing".

How will I know if my child's school is closed?published at 14:17 British Summer Time 1 September 2023

14:17 BST 1 September 2023

Alice Evans
Digital lead, BBC News education team

Marina asks: How am I supposed to know if my child’s school is closed?

If your school is closed, they should get in touch with you directly.

Education Secretary Gillian Keegan said, yesterday, that affected schools would be contacting parents directly, adding: "If you don't hear, don't worry."

The affected schools will be trying their best not to close completely. Some pupils have already been told they will be learning remotely, in temporary classrooms or at different schools.

Since the government has yet to publish the list of schools affected, we’ve been doing our own digging. Schools affected that we do know about are listed here.

What about other buildings built with RAAC?published at 14:10 British Summer Time 1 September 2023

14:10 BST 1 September 2023

Chris Goodier
Professor of construction engineering and materials, Loughborough University

What about other buildings constructed with RAAC? I work in a 1970s office building with maintenance issues - who has responsibility for checking these isseus out? Is the Government ensuring that other property owners are checking relevant buildings? Caroline, High Wycombe

Good question.

RAAC is not just in the public sector.

It could be, or might be, in any buildings from the 60s and 70s - and reaching private building owners/operators with responsibility for maintenance is more difficult than contacting those in the public sector.

Why wasn't this sorted during Covid?published at 14:04 British Summer Time 1 September 2023

14:04 BST 1 September 2023

Alice Evans
Digital lead, BBC News education team

Lee from Southampton asks: “Shouldn't this have been sorted during Covid, when schools where shut and there was a huge opportunity to make sure work could be carried out without yet again disrupting children's education?”

Ministers would probably say the reason building work hasn’t happened earlier is that they didn't know about the problem in these particular schools until very recently.

The government does say it has advised schools to have "adequate contingencies" in place since 2018, in case affected buildings needed to be evacuated.

But it’s only over this summer that a few different incidents - including a beam collapsing in one building - led the government to decide that some RAAC they’d previously considered to be low risk was actually dangerous.

That’s why they’ve now issued the more serious warning – that affected schools should put in safety measures or close off the affected part of their building.

Why is the government being blamed? Schools were notified five years agopublished at 13:59 British Summer Time 1 September 2023

13:59 BST 1 September 2023

Hazel Shearing
Education correspondent

Fredrick Bate from Dagenham asks: "Why is the Government being blamed when schools were notified/warned five years ago?

The government says it has advised schools to have "adequate contingencies" in place since 2018, in case affected buildings needed to be evacuated.

But one of the reasons it’s being criticised is because it didn’t get an idea of the scale of the problem back then.

It’s hard for schools to identify whether or not their buildings contain RAAC because it looks like normal concrete.

Many may not have known they had it back in 2018 – as engineers are needed to confirm it. It wasn’t until 2022 – four years later - that the Department for Education(DfE) sent a questionnaire to schools asking if they had any confirmed or suspected cases of RAAC. If the school said yes, the DfE sent out engineers to confirm it.

Another issue here is the last-minute change of guidance days before the start of the new term.

Previously, schools with confirmed RAAC that was thought to be a non-critical risk had been told to have contingency measures in place just in case buildings needed to close.

It was only yesterday they were told to shut those buildings unless safety measures were in place, meaning head teachers are now having to scramble to find alternative plans.

Why were the schools built like this?published at 13:51 British Summer Time 1 September 2023

13:51 BST 1 September 2023

Chris Goodier
Professor of construction engineering and materials, Loughborough University

Denise from East Sussex asks: "Why were these schools built in the first place?"

There is nothing fundamentally wrong with RAAC as building material or system. Many buildings from the 60s and 70s built from many materials are now having problems due to inadequate maintenance, and old age.

Many RAAC buildings are 50+ years old and are doing fine.

No material has a perfect lifespan. Even if they have been built the same, the health of the buildings will be in different conditions - some will be fine and some will be suffering.

How many education ministers have there been since 1994?published at 13:46 British Summer Time 1 September 2023

13:46 BST 1 September 2023

Alice Evans
Digital lead, BBC News education team

Helen Russell-Johnson asks: How many education ministers have there been since RAAC was discovered in schools? A list of names would be interesting.

The government has known since 1994 that some public sector buildings contain RAAC.

We’re not sure exactly when in 1994, but these are the education secretaries we’ve had from that year up to the present:

• John Patten (Con) 1992- 20 July 1994
• Gillian Shephard (Con) 1994 to 1997
• David Blunkett (Lab) 1997 to 2001
• Estelle Morris (Lab) 2001 to 2002
• Charles Clarke (Lab) 2002 to 2004
• Ruth Kelly (Lab) 2004 to 2006
• Alan Johnson (Lab) – 2006 to 2007
• Ed Balls (Labour Co-op) 2007 to 2010
• Michael Gove (Con) 2010 – 2014
• Nicky Morgan (Con) 2014 – 2016
• Justine Greening (Con) 2016 – 2018
• Damian Hinds (Con) 2018 – 2019
• Gavin Williamson (Con) 2019 – 2021
• Nadhim Zahawi (Con) 2021- 2022
• Michelle Donelan (Con) 2022
• James Cleverly (Con) 2022
• Kit Malthouse (Con) 2022
• Gillian Keegan (Con) 2022 – present

Note that the title has changed over the years. The names above indicate the government secretary of state in charge of the department looking after schools during that time.

Is this only a problem in schools?published at 13:42 British Summer Time 1 September 2023

13:42 BST 1 September 2023

Hazel Shearing
Education correspondent

Christopher Grierson asks: “Is the problem confined to school premises?”

No - numerous public buildings have been identified as being at risk because of RAAC, including schools, hospitals and police stations.

The Liberal Democrats have released a statement saying the government needs to "get a grip" on removing dangerous crumbling concrete from schools.

"The truth is that we should never have got to this point," said Munira Wilson, Lib Dem education spokesperson.

"The government has known about this crumbling concrete for years, but time and again has denied our children the money needed to stop schools from collapsing completely.

"Every propped-up classroom roof is a concrete sign of Conservative neglect of our school buildings."

Coming up we'll be answering your questions on RAAC and how it's affecting schools and families.

We've collated the key questions and put them to concrete expert Professor Chris Goodier from Loughborough University, BBC education correspondent Hazel Shearing and our digital lead for education news Alice Evans.

Prof Goodier will also be answering questions on the BBC News channel after 13:40 BST, and you will be able to watch him by pressing Play at the top of this page.

Hazel Shearing
Education correspondent

There are a few things we still don't know about this story, and we're working hard to bring you the answers.

One of them is how many schools are fully and partially closing following yesterday's announcement .

Just as we don't have the list of schools with confirmed RAAC (which the government says it will publish this but hasn't said when), we also don't have a full list of schools that are having to close.

It could be as many as two dozen, but we don't know for sure.

Where schools are closing, it will mean more time spent out of the classroom for children who have already spent months remote learning in recent years because of Covid. And it'll mean more childcare juggling and home schooling for parents and families.

Many of these children will have also experienced disruption because of teachers' strikes this year, which led to partial and full closures.

The prospect of more time out of school is also a concern because of high levels of persistent absence since the pandemic.

Stay tuned and we'll keep you updated as we get more information.