Eco-building with mushroom

Eben Bayer grew up on a farm in Vermont learning the intricacies of mushroom harvesting with his father. Now the Rensselaer Polytechnic Institute graduate is using that experience to create an organic insulation made from mushrooms.

"Greensulate", an organic, fire-retardant board made of water, flour, oyster mushroom spores and perlite, a mineral blend found in potting soil.

A 1-inch-thick sample of the perlite-mushroom composite had a 2.9 R-value, the measure of a substance's ability to resist heat flow. Commercially produced fiberglass insulation typically has an R-value between 2.7 and 3.7 per inch of thickness, according to the Oak Ridge National Laboratory in Tennessee.

Here's how it works: A mixture of water, mineral particles, starch and hydrogen peroxide are poured into 7-by-7-inch molds and then injected with living mushroom cells. The hydrogen peroxide is used to prevent the growth of other specimens within the material.

Source: content.msn.co.inAdded: 11 July 2007