The head of Park high, Stanmore, London, bears out the findings of the School Teachers' Review Body survey, that secondary heads and deputy and assistant heads are working longer hours than ever.
"There is enormous pressure on school leaders because the past couple of years have seen secondary schools become far more complex places," he said.
The need to consider ever more advanced computer systems, the new requirement for schools to take responsibility for the children's broader welfare and the increased burden of self-evaluation that comes with the new school inspection framework have all added to his workload. Mr Barnes estimates he works at least 66 hours in a routine week during term time, when the idea of a weekend away or a weekday night out has long been a practical impossibility.
Leisure activities or even background work reading have had to be saved for the holidays but they too are now being eaten away.
"I have been a head for 13 years and I have never known a summer where I have had so much to do," he said. "The idea of this being a time to recuperate for the year ahead is now just a joke as far as I am concerned."
He also believes other school staff are working harder and is fully behind the attempt to counter the problem through the school workforce agreement.
But Mr Barnes thinks the deal has been part of the reason for the increase in workload because of the need to recruit and manage the extra support staff to take over duties no longer carried out by teachers.
He has taken on a business manager with a deputy to try to relieve the burden on his management team but thinks funding should increase to allow schools to take on more senior staff.
"I get a lot of satisfaction from my job," he said. "But it is becoming one where the hours are beginning to dominate.
"It is not just the time. When I began as a head I was working fewer hours and they were also less intense."
The review body reveals the large amount of work carried out by teachers outside school hours. On average, a quarter of secondary teachers worked at weekends, or on weekdays before school started, or after 6pm, the same proportion as last year. Primary teachers on average carried out a fifth of their work during the same periods, compared with around a quarter in 2004.
When David Fann became a headteacher 14 years ago he regularly worked from 8am to 5pm, with the occasional evening meeting.
Now he starts at 7am, works solidly through to 5.15pm before going home, if there is no governors' meeting or PTA event, and works for another two or three hours, notching up between 65 and 70 hours a week.
Mr Fann, the head of Sherwood primary, Preston, said: "I am not a doom-and-gloom merchant and I love my job and go in every day with a real buzz. But it has become more of a struggle in the past 12 months for heads."
Changes to Ofsted's inspection regime, teaching and learning responsibility points, increasing amounts of government paperwork and dealing with better-informed parents have added to his working week.
Mr Fann, 46, said he was fortunate in having a "good governing body, super staff, good parents and keen pupils", adding: "What it must be like in an inner-city school I really don't know. I am not grumbling, I do love my job, but it is harder to maintain any sort of worklife balance."
The workforce agreement timetable:
Worklife balance clauses added to teachers' contracts; leadership and management time introduced and teachers no longer expected to do more than 20 tasks including: collecting money, chasing absences, bulk photocopying, copy-typing, producing class lists, record keeping and filing, putting up classroom displays, analysing attendance, processing exam results, collating pupil reports, administering work experience, exams or teacher cover, ordering supplies, stocktaking, preparing and issuing materials, minuting meetings, co-ordinating and submitting bids, giving personnel advice, and managing or inputting pupil data.
Teachers to spend no more than 38 hours a year covering for colleagues.
Teachers stop invigilating exams, introduction of 10 per cent guaranteed planning, preparation and assessment time for teachers, and dedicated headship time.