The firm said that the General Election would likely disrupt the spring selling season spreading demand further into the year.
Announcing another year of strong profit growth on the back of a 17% rise in completions, Persimmon said it was now building on every available site with planning.
Nicholas Wrigley, Group Chairman, said: “The typical seasonality of trading in the industry may be disturbed this year with sales rates picking up into the autumn depending upon the implications of the result of the General Election.
“To mitigate the risk to sales rates in the short term we are working extremely hard to open new sites as early in the spring season as possible.
“While planning-related pre-start conditions continue to increase the time taken to bring new outlets to market, we are pleased to have already opened 60 of the 120 new outlets planned for the first half of 2015.
He added: “We are working hard to increase our active outlet network to around 400 sites by the middle of 2015 up from 375 sites at the start of the year.
Persimmon increased home completions in 2014 by 17% to 13,509, bringing the increase in the volume of new homes brought to market over the last two years to 36%.
At the same time average selling price increased by 5.3% to £190,533, and helped to deliver a 44% increase in underlying pre-tax profit to £475m. Group turnover rose 23% to £2.6bn.
Persimmon’s operating margins steadily improved over the year with the second half performance peaking at 19%.
The house builder generated £388m of cash during the year despite acquiring 26,822 plots of new land across 156 locations, representing 200% of current consumption.
As a result the board also announced it would bring forward its 95p a share cash hand-back payment from July to April.