What constitutes a state-of-the-art energy-efficient house? And would you even notice if you were in one? Well, candles don’t flicker for a start, and they last a lot longer than normal. That’s because, where an average house in this country might have 10-15 changes of air an hour, an efficient house has less than one.

There are more benefits than just long-lasting candles, of course. Doug and Sarah Stewart’s Super E house was quick to erect, using sustainable resources, and the energy bills are predicted to amount to just £15 a week — thanks partly to a heat pump that will extract free energy from the ground.

The 2,400sq ft house, which stands overlooking the coast between Torpoint and Liskeard, north Cornwall, is the culmination of years of research — not just by the Canadian company that provides the air-tight timber frames and fenestration, but by Doug himself.

Doug, 57, has been building conventional homes in the Milton Keynes area for about 30 years. While taking a degree in building processes he became interested in sustainability and decided to build a house that would produce almost no carbon emissions, using materials from renewable sources. His floors are of Chinese bamboo, for instance, which grows quicker than oak, justifying the environmental costs of transportation.

There are unexpected benefits. The cellulose insulation — made of newspaper — is not only snug, but it also has excellent sound-deadening properties. “Acoustic privacy” is a feature of the Super E house, and in these days of the ubiquitous en-suite, that’s worth having.

The Super E programme was developed by the Canadian government, partly to promote timber export. Using Canadian design software, all essentials — lighting, space, heating, cooling, ventilation and layout — are evaluated before several large containers are despatched from Canada, containing the best part of a house. This is self-build for the 21st century.

Finding the site was tricky. Doug and Sarah were set on Cornwall, scene of their first romantic holiday, but after searching for close on five years, were ready to give up.

“It was a foggy day when we first saw it,” says Doug, “but we more or less made up our minds then and there.”

It was not the decrepit old bungalow that that appealed to them, but the site — two-thirds of an acre with views to the sea.

They paid £90,000 for the plot. The building work cost £300,000, which is probably 10% more than a conventional house of the same quality and size. The house has an adaptable layout, divided into what is essentially two flats. Doug and Sarah live upstairs, with a kitchen/office, a bedroom and a living room. All are huge with big views. The downstairs flat has a further three bedrooms, designed to accommodate occasional visits from Doug’s five children and three grandchildren.

Doug is pleased with the house, which has caused his company, DGS Construction, to be short-listed for Building magazine’s best sustainability award, and hopes to build more like it for clients.

“It’s just about attention to detail during the construction process,” says the man who won’t put an electricity socket in an outside wall for fear of causing draughts.

www.super-e.com; DGS Construction, 01908 503 147, www.dgsconstruction.co.uk

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