To understand how soy-based insulation fits into the grand scheme of your insulation choices, it helps to consider the full array of insulation materials used today:
Fiberglass: This insulation is rolled out in batts and placed between studs in a wall before the drywall or sheetrock gets installed. It's economical and can be installed by a do-it-yourselfer, but if the batts aren't sized properly and gaps are left, the cold or heat from the exterior air you don't want getting into your house will get in anyway. Plus, fiberglass fibers are itchy when they touch your skin during insulation.
Cellulose: This is wood-based, fluffy material treated with borate to repel pests. It's blown into wall cavities and attics.
Rigid foam: These are panels of stiff foam that are placed between the studs. Most foam insulation products are made from petroleum-based oils.
Blown-in foam: This is a two-part product that's blown into wall cavities (usually by certified installers) as a liquid that expands up to 100 times and solidifies into a rigid foam (think Styrofoam), sealing every nook and cranny. This is where the soybean oil-based material comes into play. Typical foam comes from petroleum-based materials and is blown into place using urea formaldehyde, which has been classified as a carcinogen and is being phased out. Soy-based foam, on the other hand, uses water as a blowing agent.
You'll find two types of soy-based foam insulation: open cell and closed cell. The former has a lower R-value (a rating of how well materials resist the flow of temperature from outside to inside a building) and is less expensive, while the latter has a higher R-value, is more expensive and acts as a vapor barrier as well as an air barrier.
Soy-based foam insulation is a darling of the green-building movement because it not only helps save energy, a base requirement for green building, but it also comes from a renewable source and is less toxic for humans. And the price will likely go down as mass production goes up.
If the United Soybean Board and the American Soybean Association have their way, soy-based products will become more ubiquitous over time, here and overseas. According to the board's Web site, "Success for soybean farmers in today's market takes more than just a good harvest. Increasing demand for soybeans is an essential part of the equation" [source: United Soybean Board].
So where will these beans show up next in our homes? Soy-based cabinets? Soy-based crown molding? Soy-based sheetrock? You can be sure all possible uses are being considered.
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More Great Links
- BioBased. http://www.biobased.net/
- PATH concept home. http://www.pathnet.org/sp.asp?id=11175
- Phone interview with building science expert Bill Robinson.
- United Soybean Board. http://www.unitedsoybean.org