Junio Anthes-Moody
People do have reason to be concerned about using foam where other alternatives are just as viable. All foams that we use are made of plastic, but they vary in the blowing agents that make the tiny bubbles that turn plastic into foam. Some foams such as foil faced polyisocyanurate (commonly called “polyiso” and has several different brand names) and expanded polystyrene (EPS) have blowing agents that are relatively benign, and have low global warming potential. Foams such as Spray polyurethane foam (which is applied in homes using specialized spraying equipment) and extruded polystyrene (XPS, commonly called blueboard or pink board) have blowing agents with global warming potentials that are much higher. Vermont passed legislation that eliminates the worst of these blowing agents, but the allowed ones still have much greater global warming potential than those in polyiso and EPS.
We can’t just eliminate foams from all of the work that we do because they have properties that aren’t easily replaced by other materials. We understand that there are issues that we need to address and improve upon, and we will continue to recommend spray foam in basements, EPS around foundations, and polyiso in a number of places. The key is to understand what properties are needed and if there are more environmentally friendly alternatives that are available that can be used by the people performing the work, and are affordable for the homeowner.
To further understand the long-term environmental impacts of any building materials researchers and contractors look at Environmental Product Declarations (EPDs) that are developed by manufacturers and industry associations. These EPDs each have a lifecycle analysis that show expected environmental impacts of those materials. These EPDs cover more effects than just global warming potential. This isn’t an easy task, but learning how to compare products this way is important for industry professionals who are interested in this work.
There is progress being made on determining the actual impact of these foams for global warming, but we have to remember that reducing fossil fuel consumption is the primary way that we have to have a major impact on global warming, and weatherization is the primary method for reducing fossil fuel consumption in existing homes. As we eliminate fossil fuels from our electrical grid, using heat pumps will become the next most important method.
More information regarding foam insulation can be found at and
Junio Anthes-Moody is an energy efficiency professional based in southern Vermont. He has been performing energy audits for over a decade and has worked in Vermont, Massachusetts and New Hampshire. He taught weatherization, mentored energy auditors, and performed thousands of quality assurance inspections in that time. Junio is working with SEON to expand its teaching programs in the year to come. See more at http://www.seon.info/
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