Housebuilder and construction firm Galliford Try said it is on track to post record annual profits, but warned that the UK's Brexit vote created "a backdrop of uncertainty" over the year ahead.

The firm, which built Wimbledon's retractable roof, said the amount of homes it completed lifted 11.2% to 3,078 compared to a year ago, according to a trading update for the year to the end of June. It added that average selling prices rose 2% to £335,000 in the period.

At its construction arm it said its order book stood at £3.5bn, the same total as a year ago. It added that the unit has secured 82% of revenues for the coming financial year, compared to 88% in 2015.

The group said it expects to post record full-year pre-tax profits in September, which the City forecasts will more than double to £133.2m.

Profits among housebuilders have been boosted by low interest rates, good mortgage availability and government aid schemes such as Help to Buy.

However, the Brexit vote and the subsequent change to a new Prime Minister prompted Galliford Try chief executive Peter Truscott to say: "Recent political events create a backdrop of uncertainty for the new financial year." But Truscott added: "The balance of our businesses and the strength of our order books mean that we are well-placed to manage the impact of this uncertainty."

The firm added that after 34 years with the business chairman Greg Fitzgerald will step down at the firm's annual meeting on 11 November. He will be replaced by the group's deputy chairman, Peter Ventress.