Headteachers, middle leaders and teachers are having to work up to 70-hour weeks to fill the gaps created by a lack of funding, Ofsted has been warned.
A survey of schools carried by the inspectorate also found that around three-quarters of headteachers who responded told Ofsted that the financial pressure facing their school was affecting staff recruitment and retention.
The finding was revealed in a new report into school finances published by the inspectorate today.
Exclusive: 'Apologise or resign,' heads tell Spielman
One headteacher of a secondary school told Ofsted: "To plug the gaps, teachers, middle leaders and senior leaders are working 60- to 70-hour weeks. We are now seeing good people leaving the profession”.
Another school leader said: "The support for those who find it difficult is not always there, meaning they continue to find it hard, don’t improve and then sometimes leave.
"This creates a vicious circle. We [senior leaders] do try to identify staff who need coaching, but the feedback cycle often slips owing to our other commitments."
Another head told the inspectorate that they questioned whether the current situation was sustainable.
They said: “I feel that we are doing the best we can with what is available to us and maintaining the standards.
"However, in the future it comes down to sustainability. If teachers can work for the long term with the additional stress and pressures they are under, then it is sustainable, but I don’t think they can. I don’t think they should have to.”
The new report also reveals that 76 per cent of primary heads and 58 per cent of secondary heads who took part in an Ofsted survey said reductions in local authority services had a "major impact’ on the financial pressure on their school.
It said some schools were spending more on pastoral care because council capacity on safeguarding had decreased, resulting in more safeguarding issues.
Ofsted was also told schools have employed a home-school inclusion officer and a qualified counsellor because this work was no longer done by the local authority.
And in one case a school was deciding whether or not to pay £17,000 a year towards a full-time on-site police officer which the local police force could no longer afford to pay for.
Ofsted’s report into school finances follows the publication of a controversial blog written by chief inspector Amanda Spielman, which suggested that some schools had "squandered" funding. It has led headteachers to call for her to apologise or resign.