The Thunderbirds garage - hidden parking is latest London craze

But this sort of hi-tech subterranean concept is no longer the sole preserve of the Tracy family and their fleet of Thunderbirds - you too can park futuristically, if you have £50,000 to spare.

The garage, which "pops up" from underneath a garden, has become the latest home-improvement craze. It uses a hydraulic platform and can be hidden under a water feature, flowerbed, or patch of gravel - or a second car.

Manufacturer Cardok has seen enquiries for its park-and-hide soar "astronomically" - sales have doubled since it was first promoted at last July's Hampton Court Palace flower show.

The garage is popular with owners of vintage cars and has been likened to the Thunderbirds aircraft hangar hidden in a mountain on a Pacific island.

Whenever the International Rescue team of puppets needed to set off on a mission the ground opened up. The modern Cardok lifts out of the ground at the touch of an electronic key fob.

Eight underground garages have already been built, four are in production and more than 10 are on order, with interest highest in Westminster, Kensington and Chelsea, Ealing, Dulwich and Highbury.

The waiting list is already four months long and experts predict demand will continue to grow as families choose to improve their home rather than try to sell in a weak property market.

Cardok managing director Alastair Soper said: "It's 100 per cent secure, far more so than a garage or driveway, and the vehicle's completely protected from the elements.

"It goes down well with insurance companies. One man with a Bentley had been charged an annual premium of more than £5,000 when he parked his car in a well to-do street but that fell to £1,500 when he installed the Cardok.

"In London a lot of people who have garages want to use them as extra rooms because of the value that adds to the house. Installing a Cardok allows them to use their space most efficiently."

Local councils are waving through planning applications because the Cardok construction allows far more rainwater to drain away into the soil than traditional paved drives.

Experts have said that the floods which brought areas of London to a standstill in the summer of 2007 were partly caused by a lack of soil to absorb the rain.

Nearly two-thirds of the capital's gardens are already at least partly paved over, amounting to an area equal in size to 22 Hyde Parks and this hugely increases the load on London's creaky drainage infrastructure.

Mr Soper said: "We install a gutter around the perimeter of the hidden platform and container at the bottom of the Cardok to collect rainwater running off a wet car when it's parked. That can be directed to water the garden and filter through the soil, rather than running off onto the pavement and putting pressure on council drains. Planning officers are very keen on that."

The lift, which takes 10 weeks to construct and about three days to install, operates silently.

Councils have given permission for them to be built in conservation areas, including the one around Ealing cricket ground, and the grounds of GradeII-listed buildings.

A Cardok "mono" lift with a flowerbed or water feature on top costs £42,000 plus VAT - plus the installation charge which varies according to ground conditions.

A lift robust enough for another car to be parked on top and lifted up costs £48,000 plus VAT and installation.