Foster + Partners made a loss of £15m in 2008 following a goodwill writedown of £15.5m.

The figure is the first slice of a total £310m writedown, which will happen over 20 years after the deal last year in which private equity group 3i took a 40% stake of the business for an undisclosed sum.

The sum is the difference between the value of the group’s assets and the transaction price. Mouzhan Majidi, chief executive, said the writedown was preferable to leaving it on the books or revaluing the company every year.

In addition to the cash injection from 3i, the architect also broadened its shareholder base and restructured its management team.

In the first results since the deal, turnover to 30 April 2008 grew 60% from £90m to £142.4m as a result of the company's global push. The pay of the highest-paid director fell 57% from £2.9m to £1.2m.

The contribution from the Middle East looks set to overtake the UK next year. It rose 51% from £17.9m to £27.1m; turnover in the UK was up 19% from £23.9m to £28.5m. The biggest slice came from Europe, where turnover grew 50% from £30.4m to £45.6m.

Majidi said: “We have projects under way in India, Vietnam, Korea, Hungary and Bulgaria.”