"Despite challenging market conditions, we have delivered a record set of interim results. We remain on track to deliver record results for this year in line with our expectations," said the group.

Pre-tax profit for the six months rose to £28.6m from £25.2m in the same period last year on revenue that increased by 48% to £1.24bn.

The group said performance improvement was largely driven by acquisitions.

The group said the outlook for social housing remains positive but it expects the division to continue to be hit during the remainder of 2008 and in 2009 by the downturn in open market house sales.