German methods for UK eco-town homes

Bidders for eco-town homes schemes are considering using German construction standards that cut heating bills by 90% instead of using air conditioners or boilers.

Eco-town panel member Liz Reason said "serious" bids so far had incorporated the use of German Passivhaus features which reduce energy so much that heating and cooling systems are not needed.

The approach trumpets improvements to the air-tightness of buildings, a reduction in heat escaping through heat bridges and maximising heat gain from the sun in winter while minimising it in summer.

Reason said Passivhaus standards could transform the ability of builders to reach levels of the Code for Sustainable Homes.

"Passivhaus has been well thought through, delivers energy efficiency and is low cost because it is about improving the fabric of the building, not putting a lot of renewables on it," she said.

Reason added that Passivhaus homes could reach Code level four without renewable energy, but were not being built by large-scale developers because of their cost.

"Passivhaus windows are significantly more expensive and there are few suppliers and no manufacturers in the UK. Homes are about 4% to 5% more expensive."

Good Homes Alliance director Tony Bootland said many members were investigating Passivhaus standards because of the wealth of historical data on their performance.

"Passivhaus gives very specific systems to employ," he said. "Thousands have been built in Germany. In the UK we talk about zero carbon but the number of properties you can find you can count on your fingers and toes."