When Kester Wilkinson came home and announced he had picked up a great idea at a weekend course — building a house of straw — his wife Zinnia initially went along with it to humour him. “I didn’t really think it would happen,” she says. “It sounded an absurd idea and I didn’t think we’d get planning permission.”

Two years later, the Wilkinsons are sitting in a light, spacious kitchen with tellingly thick walls, lime-plastered and colour-washed in mellow terracotta, in what is a charming and well-planned house. But the calm and welcoming surroundings belie the struggle and sheer graft that went into realising the family’s dream.

Kester, 33, now jokes that his decision to use straw was based on “a lethal mixture of ignorance and arrogance”.

All the Wilkinsons, who live near Ledbury, in Herefordshire, had originally wanted was an extra bedroom and a bigger kitchen and garden for their two little girls. But when they couldn’t find a suitable house within their price range, they began to investigate self-building.

While researching building materials, Kester attended a course on straw-bale barn construction run by the Yarner Trust, an environmental charity.

“Straw is a breathable, natural material and provides good insulation,” he says. “But it was also something we could easily learn to build with ourselves, which we thought would mean saving on labour costs.”

The Wilkinsons were determined to manage the entire project themselves, from design and planning through to building and finishing the interior. They drew up their own plans and got a draughtsman to tidy them up rather than employing an architect — a decision they later came to regret.

They also had to address the concerns of the building regulations officer over fire safety, but they managed to convince him that the plasterwork would provide sufficient protection in the event of a fire.

They bought a plot of land of just over an acre for £100,000, set amid picturesque apple orchards but occupied at the time by “an ugly 1950s bungalow”.

Along with daughters India, now 5, and Liberty, 3, the couple moved into a caravan on site in April 2001. This meant Kester could work on the two-storey house in the evenings after he clocked off from his office job as a contract manager for the Learning Skills Council. At the weekends they roped in friends, most of whom had little or no building experience either.

“I’m sure people thought we were crazy,” muses Zinnia, “but they were also terribly supportive and came to help when they could. It was great when it all started to shape up.”

They also managed to run a couple of courses on straw-bale construction, using their house as the practical exercise for those who attended.

“One weekend we’d got a group of people here for a course but it was raining so they couldn’t do anything. Then suddenly, the sun came out and we got the upstairs walls built in an afternoon. That was when we could see the potential. It was really exciting.”

She admits there were real lows too: “A month later the weather turned bad. It rained and rained. We hadn’t put the roof on so we just had plastic sheeting to protect the bales and nobody wanted to come and help in that weather. We really did wonder whether it was too late to turn back. We just felt so stupid.

“We now know we should have put the roof on first because the priority is to protect the bales from dampness. If they get wet they’ll rot, so you have to take them out and start again.”

The roof was a real headache. The Wilkinsons planned to use concrete tiles because they were cheap, easy to lay and looked like slate. But talking to environmental building experts, they found themselves under pressure to use a greener alternative.

Kester says: “Concrete production is seen as a highly polluting process. It was rightly pointed out that this wasn’t in keeping with the environmental ethos of the project. But switching to cedar shingle tiles doubled the cost of the roof materials and meant employing labour because to do it myself would have taken 40 days’ work.”

In addition to the roof, they brought in professionals for plumbing, electrics and carpentry — partly because they were so exhausted. In March 2002 they moved in, just less than a year after they started building.

Kester admits: “We thought it would be cheaper to use straw but in the end it turned out not to have been, because of the cost of things like the roof tiles. Employing an architect would probably have saved quite a bit of time and money because you don’t make so many expensive mistakes.”

They spent about £70,000 on the build — £20,000 more than their worst-case scenario. And although the house has been valued at £200,000, they’ve been told that had they used conventional materials it could be worth twice as much.

But Kester is philosophical: “The valuer was being cautious because there hadn’t been another one sold, so it’s hard to put a price on it. In any case, we weren’t doing it as an investment — we’d never sell it. Every morning we wake up here, it’s like being on holiday.”

And Zinnia says there’s something special about straw: “The walls curve into the window recesses. There are no sharp edges — it’s got the kind of rustic feel of an old cottage but it’s more spacious.”

They also hope to offer B&B and open the house for exhibitions of work by local artists and craftsmen. Kester says: “In the end, we can’t say whether it’s better or worse, cheaper or warmer, longer lasting or greener, but it’s the house we wanted and we love it.”

The Straw House, 01531 670 934, www.thestrawhouse.co.uk

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