Placed in a dark environment, the cells start to grow, digesting the starch as food and sprouting thousands of root-like cellular strands. A week to two weeks later, a 1-inch-thick panel of insulation is fully grown. It's then dried to prevent fungal growth, making it unlikely to trigger mold and fungus allergies, according to Bayer. The finished product resembles a giant cracker in texture.

"It really allows for a myriad of uses," said McIntyre. He said they've envisioned modifying the product to make structural panels that could be grown and assembled onsite to produce sustainable homes.

"Green building materials should be evaluated on the idea of cradle to cradle," said Evelyne Michaut of the Natural Resources Defense Council.

In the cradle-to-cradle industrial model, goods should either be fully biodegradable or reusable, limiting waste and pollution, according to Michaut, a sustainable city advocate from Santa Monica, Calif.

"That's the ultimate environmental reference," she said, adding that it seems like Greensulate is on its way to fulfilling that criteria.

For Bayer and McIntyre, their next step will be creating larger pieces of Greensulate to use in building a wall. From there, they'll perform further testing to see how the product stands up to various elements, including saturation and humidity. McIntyre said they have one two-year-old sample that's been exposed to the elements and shown no sign of degradation.

As part of their development plan, they're entering a new business incubation program at RPI to get their company, Ecovative Design, off the ground. Eventually, they hope to land a partnership with another company.

"Our biggest challenge is that while we have this technology, we still have a lot of research to do," said Bayer. "The key is to really make sure we have a product that is mature and robust before we bring it to the market."

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