This week he returned as principal to the college where he was a student for eight years.
"I did well by the college as a student, and I hope the college will do well by me as its principal," the 48-year-old father-of-three said.
As an apprentice spending one day a week at the college, he could never have imagined that he would come back to run the institution that is spread across four sites in Maidstone, Chatham and Rochester.
After gaining his City and Guilds certificates, he became a lecturer in brickwork at Erith college at 21, before taking a teacher-training course two years later.
"Around 70 per cent of the people on that course were graduates, and I realised that I must be academic too," he added. "So I went back to Mid Kent college to take a three-year degree in education."
His career then took him to Barking college, to Basingstoke and back to Barking as deputy principal. He then he became principal of Sir George Monoux sixth-form college in Walthamstow, north-east London.
After four years there, he worked for the Office for Standards in Education to set up the inspection framework for colleges, and for the past three years was director of education for Tower Hamlets in east London.
During all that time, however, he continued to live in the mid Kent area.
"It will be nice to have just a 10-minute journey to work rather than having to negotiate the Blackwell Tunnel as I have done for the past 28 years," he said.
"I left school because I was impatient to get to work and earn some money and I had a sense that I had outgrown school," he said.
Mr Grix will now supervise a pound;48 million building project at the college, with a new building in Gillingham replacing the Chatham and Rochester sites.
Will he be picking up his trowel to help out on site? "I'm probably a bit old and slow for that," he said.