Q: I heard that there is spray foam insulation that is made out of soy rather than petroleum.
Is this available anywhere in Fairbanks and does it work well?
One of the latest advances in spray foam insulation is a partial soy-based insulation. However, “soy-based” can be misleading, as the “petrochemical-based” is more accurate.
Spray foam works by combining two components, commonly referred to as the A & B components. The Acomponent is a diisocyanate (a petrochemical), which is mixed on a one-to-one ratio with the B-component that can contain modified natural or petroleum-based oils. In order to get the chemical reaction to work, the proportion of natural ingredients cannot be too high. Spray polyurethane foams can approach 40 percent natural oil, such as soy or canola oil. The total mixture, when foamed, is likely to be on the order of 20 percent to 40 percent natural oil content, depending on the recipe.
In terms of its effectiveness, the spray foam provides an R-value that is as high — or sometimes higher — than foam that do not contain soy. Spray foams are also measured in their resistance to water absorption, called a “permeability rating.” The rating of spray foam that contains soy is comparable to foam that does not contain soy.
In Fairbanks, there are spray foam installers that use soy in foam. Contact a local spray foam business for additional information.