Consultant Mouchel said it has been “relatively untouched” by the slump after posting a 20% rise in pre-tax profit for the year ended 31 July.

The figure, which excludes exceptionals, rose from £32.4m to £38.8m on the back of a 46% jump in turnover from £449m to £657m. Its order book stands at £2.1bn.

Richard Cuthbert, its chief executive, said: “Nobody can say they are immune, but we feel we are well placed to weather the storms. Given the defensive nature of our activities, we have been relatively untouched by recent financial turmoil and the upheaval elsewhere in the economy.”

The company has been protected by its limited exposure to the commercial sector. Highways work accounted for half its output in 2007, but Cuthbert said the group would diversify into the broader public sector. Highways now only make up 33% of its turnover.

Operating margins at the firm fell from 7.4% to 6.4%, which it said was a result of the £46m acquisition of HBS, the business processing outsourcing firm it bought in August last year.

He also said the group may look to expand beyond its operations in Dubai and Abu Dhabi. Cuthbert said: “We are arguably the UK leader in highways so there could be monopoly issues in the future. We’d look at entering developed highways markets in mainland Europe, Australia, New Zealand and the Middle East.”