A leading independent school charging fees of more than £25,000 a year has paid £12,000 compensation to a worker whom it was paying less than the minimum wage to work more than 100 hours a week.

Barbara White, who was an assistant housemistress at Malvern College, Worcestershire, was paid an hourly rate of £3.75, well below the minimum wage of £4.50 an hour, and was required to be on call for any problems faced by the girls in her care for six nights a week.

The case highlights the concerns of teaching unions that some staff in independent schools are being denied the most basic employment rights and that some do not even have written contracts of employment.

Mrs White’s job included locking up the girl’s boarding house at 10.30pm and opening up at 6.30am, six days a week, including Sundays. During the day she was responsible for the supervision of the domestic and catering support staff for the house, which took 30 boarders.

Her duties left her so exhausted that she was forced to take catnaps at every possible moment of free time.

When the school refused her request to reduce the number of her on-call nights from six to five a week, she took her case to an employment tribunal, supported by the Association of Teachers and Lecturers (ATL).

The school, which has not denied liability, has now agreed to pay her a £12,000 settlement out of court, before the tribunal hearing that was due to take place next week.

Mrs White, who started work at the school in 1991, said she had been sad to leave the job. “I really enjoyed working at the college and I loved the students but I couldn’t go on working those hours any longer and spending so much of my off-duty time sleeping because I was so exhausted.”

Being on call at night was very demanding, she added. “If a girl rings the bell at 2am because she has a headache or is in tears after receiving an upsetting text message from her boyfriend, then you just have to go. You have to be there for them because that is what they need and that is what their parents expect.”

Mrs White was contracted to work 121.5 hours a week for £15,138 a year, plus accommodation.

Her contract stated: “Normal working hours will be all hours each week excluding those hours worked by the nonresident (34 per week) plus a night, which you can take away from the college if you wish.”

Her case follows a previous tribunal ruling that the on-call hours of a warden at a residential care home should be regarded as part of her normal working and be reflected in her salary. Martin Pilkington, ATL’s head of legal services, said: “There can be no excuse for this type of exploitation. The irony is just incredible – a school with pupils from some of the wealthiest families in the UK, paying its own staff less than the minimum wage.”

He added that the case had significant implications for private boarding schools, which often expected staff to work extra hours, frequently unpaid.

“Potentially thousands of staff throughout the UK could also be eligible for extra pay, or should have their contracts changed,” he said.

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