The extent of trading losses emerged after assessing final positions on four price-based contracts, which completed in 2023 or are due to complete this year.
Revenue fell 19% to £881m amid the slowdown in the building market while the business endured a net cash outflow of £82m over the year.
To support the business, the McAlpine family directly funded a £60m cash injection last year and implemented a static review to refocus the business on key growth markets.
Neil Martin, who joined McAlpine in February to replace Paul Hamer as chief executive officer, said: “We faced a challenging year in 2023, but our resilience and the support of our shareholders allowed us to weather the storm.
“Thanks to our focus on operational excellence and on targeting quality work-winning opportunities for long-term clients in our core sectors, we are playing to our strengths.
“We have already seen a positive shift in performance in the first half of 2024. I have every confidence that the business is on the right path for long-term success.”
He added that in addition to the liquidity provided by shareholders, trading in the first half of the 2024 has been cash positive.
McAlpine ended the first six months of this year with £105m in cash and an order book totalling £1.4bn, an increase of £271m since the end of last year.
Martin said first-half revenues have been restored to around £500m and McAlpine’s margins had returned to industry norms.
The firm’s order book has been swollen by some flagship contract wins.
In commercial, McAlpine was recently appointed to deliver 2 Finsbury Avenue, a £500m dual high-rise mixed-use building in the heart of Broadgate, its sixth scheme under the Broadgate framework.
In the growing industrial market, McAlpine this month secured the first major build project at the planned £4bn giga battery factory in Somerset.
In healthcare, its Integrated Health Projects joint venture with Vinci Building scored a string of contracts under the ProCure23 Framework.
Martin added: “Currently, our pipeline is strong and our committed order book for 2024 stands at 99% from secured and nearly-secured work.
“As predicted, this is driven by core clients and a strong pull by some new clients who are attracted to working with us due to our reputation for engineering excellence and solving complex problems.”
