The FTSE 100 housebuilder said the outlook for the industry was less clear and it had reduced its risk by actions such as reassessing land approvals while it monitors the market.
The cautious tone overshadowed more strong numbers in the year to June with profits up 20% to £680mln, completions or sales 5.3% better at 17,319 and a surge in cash on the books to £590mln.
Total forward sales at end June were worth £1.76bn (£1.77bn), equating to 8,724 plots (8,777 plots). Wholly owned forward sales were up by 18.7% on the prior year to £1.6bn (2015: £1.35bn).
Shares fell 4% to 397p