Osborne’s construction and infrastructure business shrunk by 11 per cent in 2015.
The firm blamed falling construction turnover on market challenges such as supply chain inflation, with chief executive Andy Steele admitting the performance was “disappointing”.
However, Mr Steele added that the business had protected itself from significant price rises which occurred over the period.
The group posted a 12 per cent increase in pre-tax profit to £5.8m for the year ended 31 March 2015, up from £5.2m in 2013/14.
Groupwide turnover was down 5 per cent from £325m to £311m.
The fall in turnover was as a result of delays to project starts in its construction business, the company said.
In its financial statement released today, Osborne added: “Rising supply chain prices led to pressure on budgets and projects were delayed while they were re-designed or additional funding was found.”
The group operates across multiple market sectors, including infrastructure, property, health and education.
Mr Steele said this gave the company “some limited protection” against UK construction market conditions but meant the company was “highly selective” when seeking project opportunities.
The company’s secured order book has risen by 22 per cent year-on-year, standing at £242m up from £199m in 2014.
Osborne’s average number of employees increased by 12.4 per cent to 814. The group said this was so it could deal with the increasing number of projects that it was working on or was about to start.