The move was prompted by significant disruption caused by the lockdown and the cancellation of the group’s largest single project at the Broadmarsh Shopping Centre in Nottingham.
Developer intu stopped work in March at Broadmarsh where Sir Robert McAlpine was main contractor and it has not restarted along with the rest of the industry.
Coleman is now looking to cut staff numbers with consultation now underway.
Group chief executive Mark Coleman said: “It is devastating that good people will be leaving us as a result of this restructure, but like many other businesses in the UK we have faced the most difficult and challenging trading conditions of our lifetimes.
“We foresee our business as operating more efficiently with an annual revenue of £12million-£15 million, compared to the current level of £25 million.
“We see a future where our management expertise remains at the core of our capabilities. By leveraging industry partnerships, we will become more cost-effective and flexible.
“After 57 years in this business we have a wealth of knowledge, robust client relationships and a strong heritage to draw on.
“We will emerge from this restructure not just nimbler – and with a more scaleable model – but as leaders in the use of technology and smart partnerships to deliver the most efficient and effective results for our clients”.
Coleman is still part of an ongoing police and HSE investigation into the deaths of four demolition workers at the Didcot power station in 2016.