One reason is that finding building plots in Britain isn't easy, especially in London. But a new government policy could make it easier for motivated self-builders, with every council ordered to assess local demand for self-build and to allocate land to satisfy it.
The obvious places to find plots are though estate agents or local auctions, but David Liddicoat, a partner at architects Liddicoat & Goldhill, who built his own house in Camden, says fierce competition for sites can result in overpaying.
© Tom Gildon
"We found our plot by cycling around Camden and Islington, identifying potential sites and contacting owners through the Land Registry."
Google Earth is also a great place to search out nooks and crannies in your chosen area. But Alan Crawford of Crawford Partnership says nothing beats legwork: "Select an area and then spend a day or two meticulously combing the streets on foot, just looking for potential opportunities.
"Take a camera and notebook and log anything that may hold some potential. Once you have shortlisted several sites, it is possible to do some quick research online, often via the local planning department's web link, which will identify if someone has already beaten you to the opportunity by submitting their own planning application. If not, then it is possible to find out information on ownership via the Land Registry website for a small pre-payment."
© Francesco Guidicini
If you don't have time to pound the pavements, then Nick Waterhouse, land and new homes director at Fine in Gerrards Cross, has a solution. "See which architects are active in the area, this can be done via the planning website [of your local council]. Approach them directly and offer to pay a finder's fee."
Property potential: knock down and build
Calum Kerr, self-build specialist at mortgage broker SPF Private Clients, said self-builders should not assume they are looking for an empty site. It is popular to buy a run-down bungalow, the ugliest house in the street, knock it down and build. "The most common way is to find a site that has an existing underdeveloped property on it, in an area where there is precedence for 'knock down and rebuild'," he says.
Crawford believes in the potential of garages. "Lock-up garages are all over London and more often than not they don't get used to park cars in any more, as modern cars tend to be too large for these old structures. And families who want a comfortable old age welcome the income from selling one."
It may be controversial but the garden grab is another way to find a site. If your own garden is large enough it may be possible to hive a section off and build there, before selling your original house. If you have the cash flow, it would be worth buying a house with a suitable garden or outbuildings, then selling it on, minus the section you want.
Alternatively, you could approach homeowners with large gardens and see if they are willing to part with any of their land. James Wyatt, owner of Barton Wyatt estate agents once bought a garden plot in this way through a family friend. "Another couple bought a house with a run-down tennis court. He had looked into the history of the house and realised that the tennis court was in fact an approved building plot," he said. "Obvious building sites are modest-sized homes with large gardens — find out who owns them and write or just knock on the door."
Ian Hogarth, of Hogarth Architects, and his wife Claire Farrow found the site for their family home in West Kensington through an internet search engine. "You will be surprised how many people try to avoid paying agents' fees and sell direct," he said.
James Greenwood of Stacks Property Search, an out-of-town agency, advises a little marketing. "Put an advert in local newspapers explaining what you want," he said. "We found a plot for one of our clients in this way after they'd been searching for months.
Avoid the pitfalls when buying land
There are, of course, plenty of pitfalls to buying building land. Greenwood says it's a case of "buyer beware". Buying land and failing to win planning consent is the biggest issue. "There have been examples of quarter-acre plots of agricultural land 'with development potential' being sold for £25,000 where the chances of any planning permission being granted within a reasonable investment lifecycle are close to zero," said Greenwood.
Crawford sees another problem, particularly if you have your eye on a central London site. "The pitfalls of these plots of land in urban infill or 'backland' locations, is that they more often than not will be hemmed in on all sides by neighbouring gardens or buildings, and existing owners may not want to be disturbed by new development," he said. But it is up to you to persuade them that what you build will enhance the area with its architectural quality.