Rosebery mining manager John Lamb will take over as chief executive on January 4.

Mr Lamb is general manager of Minmetals Resources Ltd's Rosebery operations.

Mr Shaw began to step back from the business last year when he announced that his son, Cranston, would take over as asset manager.

Mr Shaw said making the decision to step down as chief executive was easy given he'd found the right person for the job.

"I think we're very lucky to have found John, it was quite a long selection process and we're a family business so it wasn't just my decision but everyone's," he said.

"I think it's just time to move on ... I'm very excited and very positive and very optimistic. I think change is invigorating for a business."

Instead of taking it easy, Mr Shaw said he would use any free time to work on other business investments and attend more meetings and functions.

"I'm still the owner so I guess I'll still be pretty involved (in Shaw Contracting), but I've got a lot of things I want to do. I want to spend a lot of time on the farm and invest more time in my horse stud, Aceland," Mr Shaw said.

"I think age decides that more than your spirit, but no, I don't think I'll slow down. I get enjoyment out of the work I do.

"It's been said that if you love your work you will never work another day in your life and I think that's true for me."

Mr Shaw said Mr Lamb would be expanding the contractor's role in the mining industry and taking it in a new direction, with the economic downturn and a lack of local opportunities prompting it to make some changes.

"Basically, we've constructed pretty much all the dual-lane highways from Burnie to Devonport, so we're looking at more opportunities outside the state," he said.