London needs more houses, so we are told. It needs two, three, four hundred thousand of them, and fast. We must therefore build higher, deeper and further, or prices will go on soaring. There must be no curb on development until “need” is met. Let rip.

Need is a dumb word, and misleading when it is a synonym for want. All booming cities — Sydney, Hong Kong, Stockholm, San Francisco — are short of space. In all, excess demand is reflected in high prices. But if a bubble bursts and prices fall, does that mean need is less? Of course not.

But in London, house prices are inflated by Government “help-to-buy” subsidies and by a global quest for a safe haven for surplus cash. Estate agents love to play down the impact of this quest, confining it to the West End. But evidence is increasing that most flats in the 400 or so towers above 20 storeys being proposed at random across the capital are now going to overseas buyers, many if not most to stand empty.

Surveys suggest there are now 50,000 flats priced at £1 million or more coming to market in the next three years. Their buyers will not “need” them, except as a safe investment. This is not a free market working, except in the crudest sense. It is a scarce commodity blighting the skyline, wrecking the townscape and destroying London’s character as a city of lively streets. We have enough grim experience of slab and tower estates wiping out cohesive neighbourhoods to make these mistakes again.

Today the richest areas of Westminster, Kensington and Chelsea are emptying of people. The last census showed the population of Kensington actually falling. Periodic sweeps by Evening Standard reporters find more districts have become “lights-out”. Blocks of flats around Sloane Square are virtually empty. I know of one resident, the last in her block to be driven out by its social decay. The Phillimores area of Kensington looks as if it has been hit by the plague, blinds drawn, doors hidden by bay trees, residents parking unused.

These are just older properties. Plutocratic blocks such as Lord Rogers’ One Hyde Park and David Chipperfield’s One Kensington Gardens stand empty, like mausoleums awaiting corpses. The Shard and Vauxhall Tower are mostly unused. Kensington and Chelsea councillors are turning their borough over to gated “zombie” estates of absentees. No children play in gardens. Shops and restaurants close. Like the Barbican in the City, this is an introverted, inhuman, anti-street urbanism.

Foreign money is not just in the West End. A recent Transparency International survey of 14 new estates across the metropolis found 80 per cent of buyers were overseas, with half of the purchase money classed as “suspicious or hidden”. Blocks of flats from Ealing to Woolwich are being marketed at “seminars” in Kuala Lumpur and Hong Kong. A Bow Group survey last week also listed towers that are almost entirely foreign owned in Manchester and Birmingham.

All of London’s mayors, Ken Livingstone, Boris Johnson and Sadiq Khan, have seen these estates as totems of a virile economy. Johnson even went to Malaysia to plead for more. Borough councils like them as they can keep some of their rates and negotiate minor social benefits from developers. Empty houses make no demand on local services.

Eventually even these markets driven by foreign money will probably level out, as did mid-Victorian properties inflated on the gains of Empire. I am convinced that Battersea’s cramped, poorly planned high-rises — little more than Malaysian safe deposit boxes — will one day slide into multi-occupancy and slums, their owners either vanishing or subletting to pay service charges.

Other world cities are trying to curb this market. Many tax foreign ownership. Britain is trying, half-heartedly, to identify “real” owners, though not foreign ones. These efforts make little difference. These places are static nest-eggs; yield rarely matters when you are laundering large sums of cash. Meanwhile, as the Chinese property website, Juwai.com, suggests, there is virtually no limit to the number of wealthy Chinese wanting London title deeds in their portfolios.

The reality is that if you don’t want foreigners to own your city, the simplest way is to ban them. Let them rent, as does Singapore. But to me, ownership is a side issue. I do not care that Qatar now owns more of London than the Crown Estate. Clearly this drives up house prices for those who want to own but then so does economic growth.

What matters is not so much who owns a city as who lives in it and uses it. In most successful cities, such as those in Germany, a flourishing rental market is the norm. The key to London housing is tenancy, the more of it the better. Renting is dynamic and flexible, while ownership is dormant. The recent Treasury war on buy-to-let was hopelessly ill-conceived. The rental market should be regulated, not curbed.

There will always be under-used homes in wealthy cities. But a systematically empty property is a market failure, an offence against urban vitality. No one knows many London properties are truly empty but regulation should focus on them.

If a property is left unoccupied for more than six months, it should be released onto the rental market, by the local council if no owner can be found. Half the blocks in Kensington could be legally squatted, with no one any the wiser. Cities are for people to use in all their variety, not ghostly totems to global greed.

As long as politicians refuse to put a stop to empty London, I will laugh in the face of those who claim that we must have ever more towers “to meet London’s housing needs”. I will do the same to those who demand an end to city conservation areas and green belts. There are thousands of houses and flats lying vacant in London and hundreds of acres awaiting renewal. And all our rulers can do about it is build more empty towers.