Contractor Henry Boot put in a strong half-year performance but warned it was unlikely to continue at the same level for the rest of the year.
Pre-tax profit at the property and construction group rose by 74% to £13.5m.
Group revenue increased from £42m to £51m in the six months to 30 June 2006. A property revaluation accounted for £2.6m of the profit, meaning that underlying interim profit increased by 60%.
However, it blamed delays in new framework contracts and Home Office prison work starting on site for a fall in turnover at its construction group.
John Reis, chairman, said that property demand in the retail and warehousing sectors was particularly strong.