Building your own house is a fun idea and, as Grand Designs proved, it makes for entertaining television. However, when it comes to actually doing it, most of us decide that it sounds a bit too much like hard work and revert to the ready-made versions. Others, such as Nicky and David Abraham, just go ahead and do it - and then make it sound easy.

“You literally start with your own drawing,” says Nicky, 27, a sales coordinator. “We bought the land from an estate agent, then worked out with an architect what would make sense, like putting the bathroom over the kitchen for the pipes and building a house instead of a bungalow so we would get views over the valley. Then we submitted the plans to the council. Once the council had agreed, we hired the builder.”

For the DIY-averse, even this straightforward version of events may seem an ambition too far. Indeed, the list of potential complications, such as not receiving planning permission or finance, is endless. But it took Nicky and David just over two years from the first spade breaking ground to the property - a four-bedroom detached house in Foelgastell, Carmarthenshire - being habitable. It's called Ty Clyd - “cosy house” in Welsh. Although they hired a builder for the foundations, walls, windows, roof and plastering, and an electrician for the wiring, they did all the internal work themselves, including plumbing, insulation, flooring, kitchen and bathroom. “We were working until 11 every night and all weekend whilst holding down full-time jobs,” David says.

Only an estimated 20,000 self-build projects are undertaken each year but, for the Abrahams, it seemed the obvious thing to do. The couple had the idea in 2003 when they finished university, inspired by Nicky's parents, who were also building their own home. They, and Nicky's sister, who had self-built, proved to be a useful source of advice and recommendations of good local tradesmen.

As twentysomethings in full-time employment, the Abrahams are not typical self-builders. The average age is 45-60, according to Potton, the self-build specialist (potton.co.uk ). However, Potton predicts that the current market downturn will help to persuade people of the merits of DIY houses. Supply is increasing as developers abandon projects and land prices are falling, making it cheaper and easier to find the land. The average cost of a project is a third lower than the price you would pay a developer, according to Joe Martoccia, a director at Potton, and “you have the added bonus of choosing your own design”.

The process can be quick, especially if you choose a timber frame, as the Abrahams did. Martoccia says that a timber frame can be erected in less than a week, and that the whole house can be finished in only ten weeks. Timber frames are also the most energy efficient, so you should eventually save on your heating bills.

Even more appealing is that home loans for self-build projects remain more generous than traditional mortgages, and offer up to 95 per cent of the costs. However, some lenders are becoming more cautious. Last week Skipton Building Society decided to reduce the maximum loan size from 95 to 75 per cent for self-builders.

Self-builders must supply at least a 5 per cent deposit. The lender offers cash in instalments; receiving the full amount depends on how well each phase of the work goes. Once this is sorted, finding the land is the next hurdle. There are plot-finders on the internet, on websites such as buildstore.co.uk and plotfinder.net, for which users pay £40 for a subscription. You can also find plots listed with some local estate agents.

“Plots of land were few and far between - we were on the verge of giving up,” says David, also 27, “then, in August 2003, we found a plot through a local agent. Our first offer was declined. We then offered £60,000, which was accepted. The plot was ours in December 2003.”

They chose the location because of its transport links: it is five minutes by car from the M4, and a 45-minute drive to Bridgend, where David works as an engineer for an insulation company. His employer helped them out with a staff discount on insulation materials, which may explain why, true to its name, it is “the warmest house in the world”, according to David.

In total, the couple spent £150,000 on a home now worth about £300,000. They had planned on selling straight away but, as Nicky says, “we liked it so much that we decided to stay. When it's your own work, you can't help but fall completely in love with it.”

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