Spray foam for the eco-consciouscomments (31) June 17th, 2009 in Blogs
I've gotten a lot of good feedback on an article I wrote for FHB#204 on spray foam. Many folks were concerned about the environmental impact of the foam itself and its toxicity to the resources we're ultimately trying to conserve. Below, I'll share a little bit about the make-up of the foam and also describe what makes some foam "green". For those of you interested in learning more about the various players in the spray-foam market right now, see the source list from my article toward the bottom of my post. And, of course, feel free to comment if you have opinions on the performance of spray-foam or its greater environmental impact.
Spray foam is made of a two-part mixture. The A part is isocyanate, a petroleum-based chemical made by only a handful of companies in the world. The B part contains a catalyst, polyol resin, a surfactant, and a blowing agent.
Consuming fossil fuels to make products intended to conserve fossil fuels makes little sense to a lot of people. All spray foams contain a certain level of petroleum in their A component and in their B component. Manufacturers such as BioBased Insulation, Demilec, and Icynene have created more environmentally benign spray-foam products by reducing the amount of petroleum used in their B component. They replace a portion of the polyol resin, which makes up 20% to 30% of the B component, with a renewable resource such as soybean or castor-bean oil. Apex even has a sucrose-based polyol. Manufacturers say that the transition to bean oil or sucrose doesn’t alter the look or the performance of open- or closed-cell foam in any way.
The amount of soybean, castor bean, or sucrose found in foam varies by manufacturer, so identifying the “greenest” foam might not be so easy. According to the U.S. Department of Agriculture, only 7% of a spray-foam product needs to be made of a renewable resource to be labeled as a bio-based foam. This, of course, doesn’t factor in the petroleum fueling the crop-cultivation process. I wonder how "green" these foams really are? Sure, they may be a bit more healthful than strictly petroleum based foams, but can manufacturers be doing more to produce a better spray foam product?
Although this is not a complete list of spray-foam manufacturers, it is representative of the larger national companies. For assistance in finding a spray-foam insulation contractor, visit the Spray Polyurethane Foam Alliance.
|Read the complete article...
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