His decision has prompted a temporary board reshuffle to continue to deliver Galliford Try’s growth plans.
Chief executive Greg Fitzgerald, who announced last month that he also plans to retire before the end of next year, will now also act as executive chairman while a replacement is found.
Peter Rogers, non-executive director and senior independent director, will also assume the role of interim Deputy Chairman to support Fitzgerald.
Ian Coull, chairman, said: “As a result of my growing business and personal commitments I have decided to step down after just under four very enjoyable years at Galliford Try.
“I leave the business in very capable hands, and in an excellent financial position with a clear growth strategy.”
Peter Rogers, senior independent director, said: “The Board is immensely grateful to Ian for his significant contribution to Galliford Try during an exciting period of growth for the Group.
“While we are sad to see Ian leave we completely understand his reasons for going. The board and I look forward to working with and supporting Greg.”