Fraunhofer: grow your own building insulation

Licensing opportunity

There is an implicit contradiction in attempting to cut down CO2 emissions by insulating buildings with polluting materials made from non renewable resources such as polystyrene or polyurethane.  

Currently only around 5 per cent of insulating materials are produced from renewable raw materials, such as reed, flax, hemp, straw or wool. Working with four partners, the Fraunhofer Institute for Chemical Technology (ICT) in Pfinztal has developed a range of new bio-based insulating materials, including one based on hemp.

Although hemp is currently used in insulating materials, these contain polyester fibres to hold the plant fibres together. In ICT’s version the polyester is replaced with a biopolymer produced from corn.

The new material is completely biodegradable, and is an effective insulator. “Its insulating characteristics come very close to those of conventional products,” says ICT project coordinator Darius Primus.

The material is light, has low heat conductivity and fulfills fire safety regulations. On top of that, it readily absorbs and releases moisture. However, at present it is slightly more expensive because the supporting biopolymer, which accounts for about 10 per cent of the volume, costs twice as much as polyester.