How can soy reduce energy use in my home?

Just when you thoughtsoybeanswere grown mainly for soy burgers andhot dogs, products made from those lively legumes seem to be everywhere in the home and beyond: behold soy-based insulation -- and soy carpet backing, soy ink,soy diesel fuel, soy animal feed and so on. Or rather, "and soy on." For example, Americans used 450 million gallons of soy-based diesel fuel in 2007, compared with 25 million gallons in 2002 [source:United Soybean Board].

And so the question arises: why soy for building materials, fuel andfood? Perhaps most importantly, as the United Soybean Board points out, soybean farming equals American jobs. Ever driven through or flown over Iowa? It's either soy orcornas far as the eye can see, and someone needs to work those fields.

Soy is a renewable and sustainable material. Consider this three-step process: plant, harvest, plant again. That's a far cry from the drilling of fossil fuels, which were eons in the making and are nonrenewable. Growing soy involves no drilling, no spilling and no sending Americandollarsoverseas.

But you may wonder; with soy used for building materials like house insulation, won'tinsectsandrodentsstop by for a meal? Not to worry -- by the time soy is transformed into an oil for use in soy-based building products, all food value is gone. In fact, these products tend to be naturally pest-resistant without added chemicals, making soy-based products attractive to those with chemical sensitivities or those who simply want cleanerindoor air.

One of the increasingly popular uses for soy is soy-based insulation. It may not be on your walls yet, but it could be in the near future. Find out how on the next page.

Soy-based Insulation

To understand howsoy-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 thedrywallor 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 yourhousewill 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 (thinkStyrofoam),每个角落和缝隙密封。这就是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, useswateras 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.

When you've got tight walls, you need extra ventilation

New and greener building materials are exciting, but for durability of the structure, the issue of compatibility comes up. How will this new material function alongside the hundreds of other materials in a home? To work out some of the issues, the U.S. government and private industry get together and build concept houses to see these products in action. Such is the case in Omaha, Neb., (home to many soy fields) where a concept house got soy-based insulation. To compensate for the amount of air that is flowing through the walls, a superior ventilation system was necessary. Tight walls (those that allow a minimum of air and moisture to flow through) are no good if fresh air is scarce. In other words, if you can still smell the breakfast bacon in the afternoon, the house needs a better air circulation system [source: PATH Concept Home].

Soy-based Insulation

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