Well-to-do Londoners are at odds over subterranean extensions - and now Parliament is weighing in
London is in a state of trench warfare. Unable to sell their homes, or discouraged by the cost of moving, more and more capital-dwellers are digging both into their pockets and the earth beneath their homes to install increasingly ambitious basements.
The trend has been growing for years, but the disturbance to neighbours has reached such a pitch the Government is trying to take action. The Subterranean Development Bill, proposed by Lord Selsdon and passed by the House of Lords last week, seeks to restrict the havoc wrought by these underground extravaganzas.
But he's got an uphill struggle on his hands, and not just because private members' bills frequently disappear down a parliamentary black hole. Underground rooms provide shelter not just from the meteorological elements, but from the economic chill.
Basement-builders calculate that by constructing a subterranean extension, they can both achieve greater square footage for less money than it would cost to move house and, with some luck, at least recoup the construction costs when the time eventually comes to sell.
Part of the problem with the new basements, of course, is the knowledge that the more spectacular the project, the more money the home owner is likely to make.
"We reckon that to excavate, support and get a basement up to ready-to-decorate status, it costs around £300 per square foot," says Maggie Smith of London Basements (formerly The London Basement Company).
According to Jeremy Best of John D Wood & Co. in Wandsworth, a really impressive basement can add 15 to 20 per cent to the value of a house in the Toast Rack. "Whereas a house round here without a basement can go for £3 million, a house with a basement will sell for £3.5 to £3.6 million."
Provided it's the right kind of basement, that is. Some 90 per cent of the London Basements schemes are commissioned not by upwardly mobile urban singletons, but by parents wanting to make room for their growing families. This is the kind of space that fetches top dollar, says Best
"The secret is not to produce some big, empty room that looks like a dance studio, but to use it as a rumpus room for the kids, with a big-screen TV and all their toys, as well as for relocated working areas like the kitchen, utility or laundry rooms," he says.