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Houses built of straw

02/04/2013

Eco-innovation is not always about new materials. Three projects in the far east and west of the European Union have shown that eco-innovation can also be about finding new approaches to old materials. In these cases, the material is straw.

In Lithuania, a construction company, Ecococon, is successfully showing that houses can be built from straw panels. The panels are made from straw tightly packed into wooden frames, which are produced in standard sizes of 300cm by 40cm, with a depth of 12cm, but which in principle can be sized to fit any requirement. Ecococon straw panel houses are built on wooden bases mounted on a waterproof layer. Once constructed, the panels can be plastered as traditional brickwork would be.

Ecococon says that the straw panels offer numerous advantages. They are not easily combustible because the straw is packed so tightly that there is little air within the panels for a fire to feed on. In addition, plastering provides a protective layer. Because the panels, and the clay plaster that can be used to render them, are permeable, moisture does not collect within the panels. Straw houses can also be long-lasting. “A well built straw house can be used for decades or centuries,” the company says.

Construction of straw houses can be done quickly. A basic structure of up to 200 square metres can be put in place by a team of a few people in two days. The construction process is low-intensity, with no need for preparation of concrete or high-energy consuming equipment - straw houses can be assembled by craftsmen with handheld tools. At the end of its lifespan, a straw panel house can be dismantled and the materials reused, in contrast to brick-built houses, which entail large amounts of demolition waste and potentially hazardous materials.

Ecococon, which started work in 2008, has constructed dozens a number of straw panel houses, and is seeking new projects.

Meanwhile, on the other side of Europe, in the English city of Bradford, an entire business park has been constructed from straw.

The Inspire Bradford Business Park consists of two buildings providing 2,800 square metres of office, workshops and shared facilities, including meeting rooms and a café. It was constructed on a brownfield site from straw panels provided by British company Modcell, and was formally opened in October 2012. The business park buildings are believed to be Europe's largest straw constructions. As well as being built according to sustainable principles, the buildings meet the BREEAM (Building Research Establishment Environmental Assessment Method) Excellent rating for energy efficiency.

Also in the United Kingdom, the European Union's Competitiveness and Innovation Programme Eco-innovation initiative is supporting the EUROCELL project. The Eco-innovation initiative is providing half of the project's €1,611,096 budget. EUROCELL is researching the certification of straw panel buildings, as a basis for market development and acceptance of the approach. The project, which also involves Modcell, is building on the monitoring of the performance of the “Balehaus”, a two-storey prefabricated straw bale and hemp clad building at the University of Bath, western England. Architects have been measuring indicators such as interior temperature, and moisture and humidity levels as the basis of a certification scheme that will demonstrate to the construction industry the viability of straw panel buildings.