If you only watched Grand Designs, it would be easy to think the whole world is running off to the countryside to build a nice little eco house.

According to the UK’s leading supplier to the self-build market, BuildStore, 20,000 people build their own home every year. But not, it seems, in Sussex.

Jake White, from Bolney eco architects Ecotecture, says: “We currently have very few green buildings in Sussex. There are a lot of green extensions and lots of refurbishments, and an awful lot of them are above building regulations, but not at the level they should be.”

There are lots in the pipeline, though, including a straw bale and steel-framed house just south of Horsham.

Tim Bailey is waiting for the final planning approval to come through on his three-bedroom, two-bathroom eco home on the main road in Southwater, and has hopes of it being finished before Christmas.

“It’s going to look like a standard town house,” he says. “It will look exactly normal from the outside. We’re using straw bale insulation and it has a very light steel frame. We’re working on getting it so well insulated it meets passivhaus standards.”

Passivhaus is a concept brought over from Germany and means, roughly, that a building is airtight, with mechanical ventilation and well thought-out use of available sunlight. This means the house is comfortable in the summer and winter without any form of heating.

By 2016, all new builds will have to broadly fit this remit but currently, in the UK, there is only one property fitting this standard.

Tim, who is, rather conveniently, the director of Advanced Structures UK, a company specialising in steel frame structures, says: “We looked at various ways of building it and a wood frame would be more usual, but the steel frame would give us the strength to use straw bales as insulation on the roof. This way we have a simple and elegant structure.”

Although he is still waiting on final approval, getting permission to build has been relatively simple as the planners only look at where the house is and what it looks like, not what it is made of.

Anita Brockelsby is the planning team clerk for Lewes District Council. She says planning applications can be approved in as little as eight weeks and, although it is being discussed, there is currently no special preference given to green buildings.

She says: “We take everything on a case by case basis but the same rules apply. For example, if it’s outside the planning boundary, it doesn’t matter if it’s an eco home.”

Of course, all this will change once the South Downs National Park is formally created, most likely around 2011.

“It’s a bit too early for us to say what it means, but it probably will be a little more difficult to build,” says Anita.

But despite that, the pay- off seems worth it. For Tim, it is cheaper to build his own than buy, and, of course, he gets exactly what he wants, complete with rainwater harvesting system, high energy efficiency and the all important straw bales.

Visit www.brighton permaculture.co.uk/gad for more information.