Looking to buy, or just snooping around?

Selling your home by open house is more popular then ever. But some critics say it only attracts time wasters. Oliver Bennett drops in on a viewing

To Fulham, home of Boden Man and Woman, and grail of the flouncier end of the property market. I'm here to see an 'open house' viewing and they seem to be popular here: I pass one on my way from the station before I even get to my destination. By the time I reach Hestercombe Avenue, south London – £1,125,000, since you ask, from (Chestertonhumberts.com) – I already know the form: beaming agent at the door with clipboard, greeting people crossing the threshold.

The gatekeeper at Hestercombe is Chesterton Humberts' agent Richard Lepper, and he's a believer in open house selling – an import that is rapidly taking hold among the nation's estate agents. "It's a great way of exposing a property to the market," he says, greeting a potential buyer on the tiled threshold. "You get instant feedback on everything, including the price." In an open house, the inhabitants are sent packing for the duration, which means that the punters don't hold back.

Hestercombe Road is rather lovely: tenanted and not as 'modernised' as Lepper would like, but pregnant with potential. As I look around – one of the advantages of an open house is that you can be as nosy as need be – I talk to some other would-be purchasers. Angela Morrison from St John's Wood, scouting property for her daughter, prefers "the older way of private viewings. They're more special." Also, she thinks, perhaps Hestercombe needs "too much work". But Marius Ostlie, from Norway, is at one with the system and prefers it. "We have it in Norway, so I'm used to it and it's pragmatic," he says, perusing Hestercombe Avenue's various parts.

The open house idea is spreading fast. In the US, the National Association of Realtors gathers that 48 per cent of would-be buyers go to at least one open-house during their home hunting. They are also popular in Canada, Australia, South Africa and New Zealand, and now it's our turn. The man who claims to have bought the technique to Britain is Chesterton Humberts' David Adams. "I introduced them when I was at Hamptons 10 years ago," he says. He believes they have great advantages. "The vendor dresses the house for an hour at the weekend, not whenever the agent calls," he says. "They love them, as selling a home is a stressful process, always getting the children to put their toys away. And from the agent's perspective competitive bidding ensues, which often achieves higher prices than private viewings."

So far, open house selling has mostly been used for top-end property in Britain, but it is becoming fashionable in terraces and apartments, just as it is in New York, where open-house hopping is seen as a post-Sunday brunch leisure jolly, to the extent that The New York Times called it "a great American weekend activity".

That buzz is definitely coming here. A new agency, Warwickshire Open Homes of Leamington Spa, recently launched with plans to use the open house method exclusively, a process that its managing director, Simon Rawlings, calls "a far better way of providing the vendor with a service that is simple and efficient". Rawlings, who started before Easter, promotes the open house for three to four weeks before the event, building it up as an experience.

The high street is catching up, too. "We use open days regularly," says Julia Green of Barnard Marcus in Sutton. "In many cases, open houses get the best prices and quickest sales. Those viewing the property get to see the competition, and this really focuses their decision." The biggest fillip to the open house system comes from Countrywide Estate Agents, Britain's largest agency group, which is about to have a UK-wide Open House Weekend on 5-6 June, with over 10,000 properties taking part. "We had the first one just before Christmas last year," says Robert Scarff, managing director of Countrywide. "We were very happy with the results, and this will be the second."

Countrywide opened up 11,000 houses and took 1,600 sales. "True, they might have sold anyway," adds Scarff. "But it's a better result than we expected."

What are the downsides? David Adams says that an open house is not good if you want to keep the sale discreet. "Some people don't like it at all," he says. "If you're selling because of death or divorce, some people don't want their neighbours to know, for instance." Plus, he adds, it's not very good for homes with "poor street-appeal" – where a high turnout is not guaranteed.

Others, like Sarah Shelly, of Knight Frank in Wapping, think open house selling isn't necessarily appropriate for the British market. "I think the Brits like hand-holding and pampering," she says. "You can't say anything without feeling that people are listening in, and buyers don't necessarily feel comfortable meeting other buyers."

Alex Thompson, director at Winkworth's Notting Hill office, isn't a fan either. "An open house can work if the open day is well-attended, as it gives buyers reassurance to make an offer if others seem interested," he says. "On the other hand, if the open day is poorly attended it can reflect negatively, giving the wrong impression of a perfectly good property." He thinks they lack both emotional appeal and flexibility. "In my view, open houses don't generally work for us or our local market," he says. "Buying a property is a huge investment and we prefer to take a more personal approach, giving buyers our undivided attention in private.

"Furthermore, in Notting Hill most serious buyers normally want to see a property as soon as it comes to market. Open days are often more for the convenience of the agents rather than the buyers or vendors."

There's certainly a lot of questioning of open houses in the US, where the National Association of Realtors' glowing 48 per cent of would-be buyers who go to at least one such showing tumbles to a mere 12 per cent who actually purchase as a result of an open house. There's also a tendency for agents to refuse to hold open houses, considering them a waste of time and also a security risk.

This is one of the most significant fears about open houses. Although agents like Chesterton Humberts make sure that all attendees are booked – and the private viewing system also poses a risk – vendors are concerned about robberies. They have happened. In 2007 in the US, two women were arrested for posing as buyers and stealing jewellery from open house apartments. "It's fair to say that security is the biggest cause for public concern," says Countrywide's Robert Scarff. "Not that anything would happen – just that people feel uncomfortable about it." To allay fears, Countrywide issues vendors with a password as well as a checklist. Still, only one in five of Countrywide's properties are opting to join the open house listing, probably due to this factor. Less seriously, there's also the idea that open house viewing can attract serial tyre-kickers. Some New York blocks ban them, only allowing showings only by appointment, to avoid roaming strangers and that nagging sense of a lack of exclusivity.

Still, as I leave Hestercombe Avenue I can see the point of open house viewing. The agents love it – two further viewings resulted from that open house – and as a curious viewer, you can have a great time. After all, it's a licence to snoop.