The firm also reported a strong rebound in tender opportunities since April, bidding for £600m of projects, mainly in the datacentre and infrastructure markets.

Many of the specialist contractor’s key sites were closed for up to three months, knocking first-half revenue by 38% to just £106m.

TClarke enjoyed a strong first three months of 2020, maintaining its 3% underlying operating margin on a turnover of £70m.

But the lockdown impacted second quarter saw turnover fall to £36m. Even during this April – June period, TClarke achieved a small profit as it acted to swiftly to cut costs and utilise Government job retention support.

Overall underlying pre-tax profit for the half fell to £1.7m from £4.6m previously while underlying operating margins were held just above 2%.

Across the regions London and the South performed well remaining in the black with London delivering  3.2% margin.

The Northern business was the only division to fall into the red reporting a £200,000 loss mainly as a result of sites over large parts of the North West and Scotland being closed from March.

Mark Lawrence, chief executive, said: “TClarke has successfully remained profitable throughout the first half of this year.

“The group took early and decisive action to both protect and reposition our business and maximise the many opportunities available in the technology, data centre and infrastructure market sectors.

“The business has paid strict attention to cash collection and our cash position has improved to £7.5m after the cost of our restructuring programme.”

He said TClarke’s banking facilities of £25m have been renewed with the revolving credit facility  extended to August 2024.

“Our order book is strong and we have no shortage of opportunities in Data Centres and Infrastructure. Since the beginning of April we have bid £600m of opportunities,” he added.