I’ve lived in London for the past eight years, and I can’t really imagine living anywhere else. I certainly wouldn’t say no to a few months in New York, and every so often I’m almost seduced by the idea of seaside living, but generally I’m passionate about my adopted city in all its dynamic, exciting, vibrant, diverse glory. However…as house prices continue to rise, I share the worries of commentators such as Rosamund Urwin  and Richard Godwin in the Evening Standard, who postulate that the exorbitant cost of housing is going to erode all those things which have made London such a wonderful and desirable place to live in the first place.

I read recently that, with global financial uncertainty showing no signs of ending, London property is increasingly seen as a failsafe investment in the way that gold or American dollars once were. And that’s the nub of the problem. For every luxury apartment sold as an investment to foreign businessmen who have no intention whatsoever of actually living in it, through to every terraced house bought as a buy-to-let investment in lieu of a pension, that is one less property where talented, creative young people can afford to live, one less property where still-quite-young people can start a family.

Nearly seventy years ago my late father-in-law, then aged eighteen, moved back to London from New York where he had spent his teenage years. He wanted to be a writer. He lived with relatives for a bit, and after a while rented a studio flat in a modern block on the Hampstead borders. His writing was experimental and intellectual, and, as such, had limited commercial appeal. He supplemented the income from his novels, plays and poetry with other bits and pieces – some translation work here, a review piece there. Many years later, now married to his second wife, they raised the money to buy the studio flat, and to extend it out onto the balcony, creating a room for the baby who was going to grow up to be (amongst other things) my husband. He grew up there, his dad continuing to write critically acclaimed but non-commercial books, his mum pursuing a career in publishing – starting off as a secretary and working her way up to become Editorial Director at BBC Books. She now runs her own literary agency, and still lives in the flat my father-in-law moved into so many years ago. When we go to visit, my daughter sleeps in the study where her grandfather used to write.

It’s a great area of London, sandwiched between Primrose Hill, Camden Town, Belsize Park, Hampstead. It’s just a half hour walk across Regent’s Park to the West End, but half an hour in the other direction takes you to the centre of Hampstead Heath where you could be a million miles away from the hustle and bustle of London Town. I’ve spent a lot of time in the area since meeting my husband fourteen years ago and I’m very fond of it, but the intellectual, bohemian culture has been almost totally submerged under the influx of American investment bankers. The idea that a young man in his twenties could buy a modest flat and live there while he pursued his literary ambitions,  contributed to the intellectual life of the nation, and raised a family, is unthinkable.

Fair enough, you could say. Hampstead was a cheap and cheerful option in the 1950s because it wasn’t Mayfair, Park Lane, or anywhere else in the upper echelons of the Monopoly board, but with the huge advantages of its hilltop location, the Heath and the beautiful Georgian houses it was always going to gentrify. But what about Walthamstow?

When we moved here, six years ago, it was because we were fed up with renting and couldn’t dream of affording somewhere to buy in Clapham, where we had been living. Ironically, Clapham, home of the eponymous omnibus which famously signifies the ordinary and mundane, had become far too expensive for a couple of twenty-something graduates in middle-management roles. We spent weekend after weekend walking round different parts of London, trying to identify those areas with the magic triumvirate of good transport links, liveability and affordability. Walthamstow was the obvious choice. Twenty minutes down the Victoria Line to Oxford Circus, seventeen minutes on British Rail into the City. A great selection of independent shops, cafes, pubs and restaurants. And our budget, which (literally) wouldn’t have bought us a garage in Hampstead, secured a lovely little Victorian terrace in the Village area of Walthamstow.

I absolutely love Walthamstow and have put down very deep roots here. These are the streets I’ve walked, catatonic with sleeplessness trying to get my baby to nap, the parks where she took tentative baby steps and the swings I’ve pushed her on, the registry office where we got married, the museum garden where we had our wedding reception and a hundred picnics, the cafe where I wrote my first book, and the shop/gallery where I launched it. The church hall where my daughter attended pre-school, and the church where we’ve sung carols. The friends I’ve made at baby groups, toy library and the school gates. The butcher, pizza chef, hairdresser, fishmonger, newsagent, pharmacist and local MP all of whom I know by name.

I can’t be hypocritical enough to complain about gentrification – I benefit from the gastro-pubs, vintage market, organic vegetables and posh cakes as much as the next thirty-something, sometime Bugaboo Bee pushing, Converse wearing woolly liberal mother. However, I discovered last week that Walthamstow, which I thought of as a refuge for normal people, creative people, public sector workers, in the ever-increasing madness of the London property market, is in serious danger of losing that status.

Some friends of ours, currently living in a one bedroom flat in South West London with their baby daughter, are looking to buy a family home. We recommended Walthamstow enthusiastically, and last week they came to have a look round and register with some estate agents. Depressingly, their budget (the same amount, by the way, as bought our little house six years ago) caused the estate agents to look at them with eyebrows raised in disbelief. We’re happy to buy something which needs work doing, they explained, but the response, pretty much was ‘you should be so lucky’. This couple both have degrees and masters degrees from top universities, and they’ve chosen to use these skills to bring history to life for others by working in the museum sector. It’s not an especially high-earning profession, but it should be enough for a couple, both working full-time, to buy a family home in a pleasant but ordinary area. It isn’t.

Which is what leads me to worry that property prices are ultimately going to kill London. I’ve got nothing against bankers, lawyers and management consultants per se, but a city populated entirely by these professions wouldn’t be able to lay any claim to being the greatest in the world. What makes London so intoxicating and fascinating is the mixture – nurses, teachers, artists, academics, writers, waiters, chefs, shop assistants – living in the same communities, sharing experiences and ideas, forming a cohesive whole.

Last night’s Homes and Property section in the Evening Standard suggested that an average three-bedroom house in Walthamstow Village is now ‘worth’ £650,000. A couple would need to be earning around £200,000 a year and have saved a deposit of £60,000 to afford that. The privilege we enjoy of owning our own house in an area of London we love is an accident of chronology. If starting now, there’s no way we could afford to buy the house we live in. I feel both lucky and guilty. If something doesn’t change then London risks becoming a wealthy, but sterile, ghetto.

I don’t pretend to know what the solution is, but I do know that we have to stop seeing rising house prices as a cause for national celebration, or falling house prices as an indication of economic gloom. I know that stamp duty has become a regressive taxation. I know that ceasing to build social housing and continuing to sell off what we’ve got provides no sort of sustainable solution. I know that bricks and mortar should be treated as homes not investments. And I know that what will keep Walthamstow, and, indeed, London, awesome, is finding a way in which it is not only the very wealthy who can afford to live here.