The Rocky Mountain Institute reports in the Cool Citizens Report (PDF) that the typical homeowner could save about 28% in heating and cooling costs by improving insulation and tightening air leaks in your roof and walls.  That accounts for an estimated $400 savings each year for the typical American home. And if you have an older home, savings could be substantially more.

Spray insulation is the quickest and easiest way to get these big improvements because it both seals and insulates at the same time, and it can work on top of old insulation.  But until recently the materials used to create spray insulation were petroleum-based and required toxic chemical compounds as blowing agents.  BioBased insulation solves the problem by using an abundant crop available in the US -- soybeans.  The soybeans are used to make a 96% pure bio-based polyol which uses only water as a blowing agent.

How it works...once sprayed, the foam expands 100 times inside your wall cavity, sealing up the thousands of leaks that inevitably occur in wood-frame construction.  And unlike other forms of insulation, like batt fiberglass, BioBased insulation will never settle, so the performance of the insulation does not decrease over time. The more advanced 1701 class of bio-insulation offers R-28 insulation at 5" thick, compared to the R-19 of typical batt insulation.

Many people understandably think that since it's made out of soybeans, the BioBased insulation would provide food for insects.  Not true...the foam is inert (though eventually biodegradable).  In fact, an added benefit of the spray foam, is that it blocks the path of entry for dust mites, pollen, volatile organic compounds, and other allergens.  BioBased insulation is also fireproof and acts as a vapor retarder.  

It's not surprising that BioBased has earned just about every building product award possible, including the hard-to-achieve GreenGuard rating.  You can visit their website to learn more about cost of installation (a few thousand dollars, from what I understand) which depending upon your home size and location, could pay for itself in just a few years though increased energy savings.

 Table: Rocky Mountain Institute, 2005

BioBased spray insulation could save 28% on utility bills
Soy beans provide a cheap, nontoxic and renewable way to insulate your home.