The head of one of the country’s most prominent academy chains has voiced concerns about an increase in workload caused by the planned new Ofsted framework.

Dame Rachel de Souza (pictured), the chief executive of the Inspiration Trust, also told Tes it was important that Ofsted did not direct schools’ approach to the curriculum.

The inspectorate is developing plans for a new framework that will be used to inspect schools from next September. It will place a greater emphasis on how schools deliver the curriculum and has been seen as a crackdown on “exam factory” schools that place too much emphasis on results.

Ofsted has visited two Inspiration Trust schools as part of its research into how “good” and “outstanding” schools develop their curricula.

However, Dame Rachel has questioned whether developing a new inspection framework should be Ofsted’s highest priority.

“Ofsted has got to concentrate on the quality of its HM inspectors,” she said. “I have obviously gone through lots of inspections and that is an issue you always think about.

“I also think about the workload when changing the new framework. When our schools are dealing with changes in examinations and we are working on developing our own curriculum, a new framework feels like it will cause additional work.”

Dame Rachel said that it was right that Ofsted focused on curriculum but added that they should not look to direct the approach taken by schools.

The watchdog’s preparatory research has already prompted concerns that Ofsted favours a knowledge-based approach - which the inspectorate has denied.

Dame Rachel’s comments are only the latest in a long line of blows to the watchdog’s plans to overhaul school inspections.

Yesterday Teach First chief executive Russell Hobby warned that the changes would be incompatible with having a neutral stance on teaching methods and curriculum design.

And Professor Dame Alison Peacock, chief executive of the Chartered College of Teaching, said they would leave school leaders “in fear and dread”.  

Tensions have been rising between the Department for Education and Ofsted about the inspection framework. 

Education secretary Damian Hinds has repeatedly failed to back the inspectorate’s plans and raised concerns that they might increase teachers’ workload.

Meanwhile, the NAHT headteachers’ union has urged chief inspector Amanda Spielman to “pause” the changes.

An Ofsted spokesperson said: “Our changes to the inspection framework will do exactly what Rachel de Souza is asking, focusing on the curriculum and bringing the conversation back to the substance of young people’s education.

“That is after all the reason teachers entered the profession in the first place. We want to treat teachers as the experts in their field, not simply data managers, and that will also help to reduce unnecessary workload.

“We have campaigned hard in recent years to bust myths about inspection and communicate clarifications about our expectations. As we develop the new framework we will continue to take this further and reduce the scope for external consultants to promote workload increasing practices.