Life
Clay and straw - ancient building materials used in eco-homes
By Reino Gevers
Sep 28, 2006, 19:00 GMT

Lueneburg, Germany - For centuries people in the central European plains built their homes with clay, straw and timber. Now these ancient building materials are again being used in modern eco- homes as a low-cost and energy-saving alternative.

Germany was the first European country to approve earlier this year straw as building material after several research institutes found that the insulation is better than most products currently on the market.

Last year the eco-village 'Sieben Linden' (Seven Lime Trees) in the eastern German town of Poppau unveiled the first new house in the country built almost entirely with straw bales, clay and timber.

The basic building principle is centuries old. The frame consists of timber supported by straw bales with clay plaster. The straw, normally a waste product on farms from harvested wheat, oats, barley or rye, is compressed into bales.

The difference however is that the new straw bale construction offers all the amenities of a modern home. Solar panels on the roof supply warm water and electricity. The insulation is so effective that additional heating is only required in the colder winter months. The compressed straw has also been found to be no less a fire hazard than conventional insulation materials.

'We see great potential for this building method. A straw bale construction has much less of an impact on the environment with the benefit of a very healthy interior climate,' says Dirk Schamer, chairperson of the Association of German Straw Bale Constructors in the northern German town of Lueneburg.

Building a straw bale eco-home is about as expensive as a normal brick home, says Schamer but the energy required to just build a normally insulated modern home is as much as the straw bale home uses over 15 years.

The Sieben Linden village, which currently has 100 inhabitants, is planning to build several more straw bale homes, all according to the principle of sustainable development. Currently electricity usage for each inhabitant is 400 kWh per person per year, only a third of the energy used by the average citizen in Germany.