LONDON (Reuters) - UK housebuilders have lost as much as 40 percent of their value since Britain voted to leave the EU, as the threat of recession erased their standing as safe haven stocks.

A worker drives a dumper truck past a house being built on a construction site in Chester, northern England March 20, 2013. REUTERS/Phil Noble

About 8 billion pounds has been wiped off the market capitalisation of the country's four biggest housebuilders, Taylor Wimpey TW.L, Persimmon PSN.L, Barratt BDEV.L and Berkeley BKGH.L, since the result of Thursday's referendum.

“You’ve gone from certainty and clarity and confidence to a complete lack of,” Shore Capital analyst Robin Hardy said.

Those housebuilders have over the last five years reported steady profit growth and rewarded investors with higher payouts after recovering from the 2008 financial crash. They had said there was more growth to come.

But uncertainty about the outcome had already started to send shudders through the sector ahead of the vote, with Berkeley warning earlier in June that there had been a 20 percent drop in reservations of new homes.

Top economists say a recession is now on the cards, prompting fears of higher unemployment, falling consumer confidence and as a result, lower housing demand and a question mark over housebuilders’ future profitability.

“You’re going to have masses of different opinions about what’s going to happen to transaction levels, what’s going to happen to pricing, what’s going to happen to costs, what’s going to happen to mortgage lending, what’s going to happen to policy,” Hardy said.

Canaccord analyst Aynsley Lammin said that there was a risk to his consensus forecasts for the housebuilders, but noted that the sector was in a strong position to withstand any downturn.

“They haven’t got a huge amount of debt, most of them have got net cash and they’ve been very disciplined, so I think there’s some valuation support at some point,” he said.

Extending losses from Friday, shares in Barratt were down 19 percent at 1140 GMT on Monday, while Taylor Wimpey lost 17 percent, Persimmon was down the same and Berkeley was off 13 percent.

Building supplies firm Travis Perkins was trading 15 percent lower, while housebuilders on the midcap index, Redrow, Bovis and Bellway were down 20 percent, 16 percent and 17 percent respectively.

Also weighing on the housebuilders’ outlook will be a warning issued by British Finance Minister George Osborne in May that should the UK vote to leave the EU, British house prices would fall 10 to 18 percent.

The Leave campaign had sought to play down some Brexit warnings calling them part of a “project fear” campaign, but should those warnings turn out to be correct, they could almost wipe out the housebuilders’ margins.

Taylor Wimpey, for example, reported an operating profit margin of 20.3 percent in its last financial year.