A strong performance from its American business drove interim pre-tax profit up 21% to £360m at materials company Wolseley.

Whereas the UK market was estimated to be down 4% on the same period last year, Wolseley's operating profit in the UK and Ireland rose 2.8% to £87m for the six months to the 31 January.

Charlie Banks, Wolseley chief executive, said: "The US economy is chugging along. Interest rates are creeping up but not by too much and our investments there are paying off."

He said that in the UK, Wolseley expected "modest profit growth" in the second half compared with the same period in 2005.

Of the £436m Wolseley spent on acquisitions in the six-month period, £225m went on the UK and Ireland, compared with £185m in North America.

Banks said that although further acquisitions were on the cards, the company was taking to a "disciplined" approach to them.

Turnover rose 26% to £6.7bn, and the board recommended an interim dividend of 9.85p a share, up 12%.