Expanded-foam plastics could be a thing of the past thanks to mushroom insulation that is sustainable and safe.
Much of the warmth inside homes today is down to insulated walls and roofs that keep heat inside and cold outside. But thermal insulation is not all that advanced. It mostly consists of plain white sheets of Styrofoam, a material first made in 1941 and trademarked by the Dow Chemical Company.
Over the past decade its use has come in for widespread criticism because of its detrimental effect on the environment, bobbing around the world’s oceans and lingering on landfills for thousands of years. Until recently there was no lightweight, environmentally safe alternative.
In 2007, while studying at Rensselaer Polytechnic Institute, in Troy, New York, students Eben Bayer and Gavin McIntyre grew a strong but lightweight substance using mycelium (mushroom ‘roots’) that they used to bond agricultural byproducts like corn stalks into a material that could replace plastic foam. It took a while for them to realize that the experiment had enormous potential as an insulation and packaging material. Once that idea took hold, they went all the way.
After years of product development and testing, and the foundation of a commercial enterprise called Ecovative, they now grow and sell 100% natural packaging and insulation material that is extremely light and fully decomposable.
To illustrate the potential of grown-in-place thermal insulation, Ecovative built a tiny mobile home. It features walls of insulation sandwiched between inner and outer walls. The mushroom insulation grows inside timber formwork over the course of a few days and dries over the next month to leave an airtight wall that is so strong that no studs are required, thus saving on material costs. It also insulates well since it’s one continuous wall without any thermal bridges. And it has a Class A fire rating.
Ecovative is now using the same technology to develop more new materials such as structural insulating panels and acoustic ceiling tiles. Soon everybody will be able to grow their own home, and the sooner, the better. A foam-free future beckons.