A new mansion has been left precariously close to a steep cliff after a large patch of land at the end of the garden slipped into the sea.

Phillip and Daniel Julyan, a father-and-son carpentry team, were putting the final touches to the house at Dawlish, in South Devon, when they heard a roaring sound.

Daniel Julyan, 19, said: “Quite often we’ll hear a rumbling when a train goes by but this just kept going and got four or five times louder. It was like thunder.

“The next thing I knew, five trees at the end of the garden just toppled over. We looked over the edge and there was a mile of red dirt and branches and stuff floating in the ocean. The only good thing is it’s opened up an even better view.”

The four-bedroom house is being built for Nick Skilton, 47, the millionaire owner of a vending machine company. It has a glass spiral staircase, an indoor swimming pool and a sea view, through 30 large windows, that is now unimpeded by the Scots pines that were there last week. The property is in the back garden of Mr Skilton’s home on an exclusive cliff-top road.

Mr Skilton says that he is unconcerned by the landslip. He said: “Yes, there was a big slide but it doesn’t affect me at all because it is not my land.”

The L-shaped piece of land that fell away last Thursday is about 80 feet (25m) at its longest. It belonged to Character Homes, a local developer that is building a three-storey apartment block 650 feet from the cliff edge, on the plot next door to Mr Skilton’s home.

Character Homes had intended the lost land to be a wildlife area. Michael Hogg, 50, who owns the company, said: “There is just a sheer drop there now. I have to say we were very surprised, but luckily it doesn’t affect any of our plans. We have just lost a few trees and snowdrops. We really have no reason to be concerned but it has put the new house very close to the cliff face indeed.”

The Julyans were in the habit of eating their lunch within metres of the lost cliff edge. The cliff top has now been fenced off. A survey will be conducted this week to find out whether more of the cliff, and possibly the house itself, are in danger of falling into the sea.

Mr Julyan said that a geological study before construction began 18 months ago showed that the house was built on solid rock. He added: “Normally we’ll have a sarnie near the cliffs. We’ll be eating lunch somewhere else from now on.”

Mr Skilton made his fortune supplying vending machines to the prison service, hospitals and fast-food restaurants.

Slippery slopes

— The Holbeck Hall Hotel, Scarborough, fell over a cliff in 1993
— Clavell Tower, a 19th-century folly on a cliff at Kimmeridge Bay, Dorset, is being rebuilt 80ft inland
— Homes on Seaside Road, Aldbrough, in Yorkshire, are falling into the North Sea
— 1,062,000 properties are thought to be at risk from flooding and coastal erosion

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