Some others are having to put in "mitigations", for example closing some school buildings.

The Department for Education (DfE) has newly identified 104 schools and sixth forms with problems, but it's understood a full list of them will only be released when all parents are informed and mitigations are in place.

In the meantime Sky News has identified dozens of schools that are impacted.

Below is a list of schools that Sky News has independently confirmed as being affected by the reinforced autoclaved aerated concrete (RAAC) issue.

This is followed by a list of schools that have been reported elsewhere as being affected.

Sky News has verified:

Aston Manor Academy, Birmingham

No students are expected to be on the school site until at least 11 September.

Clacton County High School, Essex

The school will be closed for all year groups on Monday, 4 September, with different arrangements by year group for the rest of the week.

Corpus Christi Catholic School, London

Crossflatts Primary School, Bradford, West Yorkshire

East Bergholt High School, Colchester, Essex

The school is considering delaying its opening or only opening some areas and is expected to update parents on Monday.

Eldwick Primary School, Bradford, West Yorkshire

Ferryhill School, County Durham

The start of the new school year has been delayed, the school says. New starters are expected to start a week late, with the rest being taught online.

Hadleigh High School, Hadleigh, Suffolk

The school is considering delaying its opening or only opening some areas and is expected to update parents on Monday.

Hockley Primary School, Essex

Honywood School, Colchester, Essex

Some 22 classrooms are expected to close with immediate effect, with some pupils to do online learning and a rota system for year groups attending school.

Kingsdown School, Southend, Essex

Mistley Norman Church of England Primary School, Essex

Our Lady's Catholic High School, Fulwood, Lancashire

School to be closed Monday, 4 September and Tuesday, 5 September.

Ravens Academy, Clacton-On-Sea, Essex

The school will be closed for two days after RAAC was found in a roof.

Scalby School, Scarborough, North Yorkshire

Springfield Primary School, Chelmsford, Essex

St Anne's Catholic Primary School, Harlow Green, Tyne and Wear

St Bede's Catholic School and Byron Sixth Form College, Easington, County Durham

Opening delayed until 5 September.

St Clere's School, Stanford-le-Hope, Essex

Parts of the school will be closed, with years 7, 11 and 12 prioritised for face to face learning.

St Francis Catholic Primary School, Ascot, Berkshire

St James Catholic School, Hebburn, Tyne and Wear

St John Bosco Catholic Primary School, Sunderland, Tyne and Wear

The school will be closed on Tuesday, 5 September, on which date further information is expected to be provided.

St Leonard's School, Durham, County Durham

The school will not reopen for its first week after RAAC was found in panels used in the construction of the school building.

St Mary Magdalene Academy, London

St Teresa's Catholic Primary School, Darlington, County Durham

The school will not reopen until at least 11 September.

St Thomas More Catholic Comprehensive, Eltham, London

St William of York Catholic Primary School, Bolton, York

The school is putting up temporary support structures and staff hope to reopen to as many pupils as possible on 11 September.

The Appleton School, Benfleet, Essex

Three areas have been closed and three year groups are not expected to be back to school this week.

The Billericay School, Billericay, Essex

Arrangements have been made for some years to be on site while others learn online.

The Bromfords School, Wickford, Essex

The Gilberd School, Colchester, Essex

Years 8-11 will return to school on 11 September, with Year 7 pupils returning a day later.

Thurstable School, Essex

The school's website has set out a phased reopening, with some years coming in and work also set online.

Waddesdon Church of England School, Buckinghamshire

Willowbrook Mead Primary Academy, Leicester

The school says it will be closed on Monday, 4 September.

Wood Green Academy, Wednesbury, West Midlands

The school says disruption to the start of term is possible and is conducting further investigative work.

Woodville Primary School, Chelmsford, Essex

School closed until 11 September.

Other schools reportedly affected:

Abbey Lane Primary School, Sheffield, South Yorkshire

Altrincham College, Timperley, Manchester

Baynards Primary School, Essex

Canon Slade School, Bolton, Greater Manchester

Carmel College, Darlington

Carnarvon Primary School, Bingham, Nottinghamshire

Cockermouth School, Cumbria

Cranbourne, Basingstoke, Hampshire

Donnington Wood Infant School and Nursery, Donnington, Shropshire

St Andrews Junior School, Hatfield Peverel, Essex

The school is reportedly closed until at least mid-September.

Holy Trinity Catholic Academy, Newark, Nottinghamshire

Jerounds Primary School, Harlow, Essex

Katherines Primary Academy, Harlow, Essex

Mayflower Primary School, Leicester

Myton School, Warwick

Outwoods Primary School, Atherstone, Warwickshire

Parks Primary School, Leicester

Roding Valley High School, Loughton, Essex

Sale Grammar School, Sale, Manchester

St Gregory's Catholic Science College, Harrow, London

Stanway Fiveways Primary School, Colchester, Essex

The Ramsey Academy, Halstead, Essex

White Hall Academy, Clacton, Essex

Winter Gardens Academy, Canvey Island, Essex

Wyburns Primary School, Rayleigh, Essex