The firm is also understood to be bogged down in several legal claims for payment.
Sources told the Enquirer that staff have been told to return cars and phones today ahead of an announcement expected to confirm that insolvency partners with accountant KPMG are to be formally appointed.
One subcontractor working on a major education site said: “We were not paid at the end of last month and neither were a lot of other specialists on the site.
“We couldn’t get in touch with them to talk about what was happening, which set the alarm bells ringing.”
According to documents filed with the court on 3 December, Clugston Group, Clugston Construction and the haulage business Clugston Distribution Services have all filed notices of intention to appoint administrators.
Latest published accounts for the family-owned business in year to 31 January 2018 revealed record revenue had been achieved, up 49% to £176m.
But this failed to translate into profits with the group booking a £500,000 loss.
At the time, Clugston also reported net assets of £14m with year-end cash of £30m and no bank debt.
Chairman John Clugston, the son of founder Leonard Clugston, last month announced he would be retiring in January 2020, with the plan to hand over to David Clugston.
The business, which was founded 82 years ago, earned a reputation for treating its staff well, and grew rapidly on the back of the boom in energy for waste plants where it built up a strong business relationship working with French process engineering business CNIM.
Presently it is working on an £800m energy recovery facility on Deeside, a £220m resource recovery centre in Avonmouth and £210m combined heat and power plant in Grangemouth.