Insulating your home may help the environment by lowering your energy usage, but unfortunately the petroleum-based foam that's typically used as insulation isn't all that eco-friendly itself. Researchers at Germany's Fraunhofer Institute for Wood Research, however, have developed a reportedly greener alternative that they claim works just as well – it's foam made from wood.
To produce the foam, wood particles are first ground so small that they form into a slimy solution. A gas is then added to that slime, causing it to take on a frothy consistency. Once that froth hardens – a process that is "aided by natural substances contained in the wood" – a dry, porous foam is the result. The finished product can take the form of either rigid foam boards, or flexible mats.
The slime can also be converted into foam via induced chemical reactions.
"We analyzed our foam products in accordance with the applicable standards for insulation materials," said Fraunhofer's Professor Volker Thole. "Results were very promising; our products scored highly in terms of their thermo-insulating and mechanical properties as well as their hygric, or moisture-related, characteristics."
While other wood-based insulating mats and wools do already exist, they have a tendency to shed fibers and to compress in the middle as they settle.
The Fraunhofer team is now researching what types of wood work best, along with how to scale up the foam-making process to commercial production levels. Needless to say, the eco-friendliness of the foam will depend largely upon how many trees need to be harvested in order to supply the raw material. Hopefully wood waste from existing industries could be used, as is the case with wood-based foams being developed at the Hebrew University of Jerusalem and the University of Freiburg.