Sir Robert McAlpine made a £23m pre-tax loss in the year to 31 October 2017, after problems on three energy projects.
The firm has now taken the decision to pull out of the energy from waste sector after "considerable" losses on the contracts, for which it had to set aside £37m worth of exceptional items in its annual accounts, filed at Companies House.
Revenue at the business was up 5% for the year to £892m, while underlying profit, not including exceptional items, was £14m.
The company also hailed its strongest secured order book pipeline for ten years.
In accounts for Sir Robert McAlpine’s parent company, Newarthill, director Cullum McAlpine said: "Over the course of 2017, Sir Robert McAlpine worked on three energy projects, all of which have incurred considerable losses.
"Two of these were ‘energy from waste’ projects which were completed during the year; the final accounts have been agreed with the client and all claims settled. The last project is forecast to be completed by October 2018."
Chief executive Paul Hamer, who joined Sir Robert McAlpine in July last year and has led a strategic review into the market sectors in which the company operates, said: "Whilst, our 2017 financial results are disappointing and directly attributable to our exposure to the waste to energy sector, I am encouraged that our reinvigorated focus on engineering and operational excellence is already having an impact on our business performance.
"Our results for the first 6 months of 2018 are in-line with budget and our secured order book is stronger than it has been for the last 10 years.""
He added that the company would build upon its strengths in key sectors such as commercial offices, build to rent, health, retail and education.
It will also place a focus on technology and creative digital innovation.