Chief executive Chris Cole said that he expects debt to stand at £43-44m when the full-year results are published.
Cole said that net debt would have been £5m less in June but for a final payment for New York building services engineer Flack + Kurtz, which was acquired in 2000. The firm is thought to be well-placed to work on the World Trade Centre redevelopment.
The results for the first six months of this year represent something of a turnaround for the business, even though pre-tax profit fell from £4m to £3.5m. In 2002 the company made a pre-tax profit of just £400,000 – 96% less than the previous year.
Turnover also increased slightly, rising from £143.8m to £147.5m. The order book has also reached a record of £350m.
Cole said: "It is quite a turnaround from the second half of last year. We have adjusted – we have got more public sector work and a little less private sector work. We are more aligned to prevailing markets."
Chairman David Turner said: "Turnover and margin growth [are] being achieved in transport, infrastructure and environmental markets, while the private property sector remains flat."