Abramovich's new pad - and why he may have unwanted guests

As the 15th richest person on the planet and employing as many as 40 bodyguards, Roman Abramovich is deservedly regarded as someone who values his privacy and would take a dim view of members of the public popping their heads over his garden fence.

It is therefore a fair bet that the Russian plutocrat and his girlfriend Dasha Zhukova will not be in residence at their new £25m "stop gap" mansion in one of London's most expensive addresses on 17 September this year, when the doors are opened to the hoi polloi on a neighbouring property owned by the National Trust.

While most people head for the in-laws or buy an on-site caravan when the builders move in, Mr Abramovich, 44, has bought the nine-bedroom, 10-bathroom house in Chelsea as a temporary abode while another piece of prime London real estate belonging to him is converted into his £150m showpiece residence.

Such is the extent of the renovations ordered by the Chelsea FC owner on the block in Knightsbridge, that the work could take as long as three years to complete, although once finished the 30,000sq ft property should be the most expensive home in Britain.

In the meantime, the house overlooking the Thames and previously occupied by such diverse luminaries as the artist Whistler and society fascist Diana Mitford, should keep Mr Abramovich, Ms Zhukova, 29, and the couple's one-year-old son in the manner to which they are accustomed.

But while the imposing Grade II-listed home has many of the features that are required by a billionaire in search of a modest pad, such as parking for eight cars, a music room and a separate annex for domestic staff, it does have one small shortcoming that might trouble publicity-shy high rollers. The handsome property was once part of the original manor house of Chelsea built on the site of Sir Thomas More's garden, which is now owned by the National Trust. The Trust leases its part of the mansion to tenants but opens the entrance and gardens, designed by Sir Edward Lutyens, on certain days.

One such occasion will be the annual Open House London day on 17-18 September, when hundreds of important or unusual properties normally closed to the public are opened up. The event will mean that visitors to this corner of Chelsea admiring the shrubberies, including a mulberry tree similar to those planted by Sir Thomas, will be able to crane their necks for a rare view of Mr Abramovich's back garden and possibly his taste in interior design.

Property experts expressed surprise that the oligarch, worth some £14bn, had settled for a home which is easily overlooked by the great unwashed. Simon Barnes, a property search agent, told The Sunday Times: "Most people at that price level have a problem with this free access."

Mr Abramovich is famously protective of his privacy and his personal safety. When abroad, he has a further protection squad for visits to his £15m chateau on the French Riviera or mansions on the outskirts of Moscow.

Like any other self-respecting member of the globe-trotting elite, his largest yacht, the 557ft Eclipse, has a military-grade missile defence system, bullet-proof windows and armour plating around the main bedroom suite.

It is unlikely such mod-cons will be needed in the billionaire's new residence. Instead, Mr Abramovich may install some recent purchases. The art lover has built up an impressive collection, with works by Lucian Freud and Francis Bacon. The decision this month by the London-based, mystery owner of the world's costliest painting, Picasso's Nude, Green Leaves and Bust, to loan the £66m work to the Tate Modern prompted speculation its owner is Mr Abramovich.

The tycoon's property

London

Properties in Knightsbridge and Chelsea worth, respectively, £150m and £25m

France

A chateau at Cap d'Antibes on the Riviera worth around £15m

America

Owns two houses in the exclusive ski resort of Aspen, Colorado

The Caribbean

Two houses on the island of St Barts

Russia

Two mansions near Moscow and a flat in the far eastern province of Chukotka