EcoRenovator - View Single Post

Nanie29 · 01-04-12, 12:56 AM

Can insulation materials, which we use to save energy and help prevent climate change, cause greenhouse gas emissions? Yes, in two ways.

First, it takes energy to produce and ship these materials--which we refer to as "embodied energy"--and using fossil fuels for these energy needs releases carbon dioxide (our most significant greenhouse gas). So in a sense, all insulation materials have embodied global warming potential (GWP).

Second, two of our common insulation materials are made with hydrofluorocarbon (HFC) blowing agents that are very potent greenhouse gases. Extruded polystyrene (XPS), best known by the brands Dow Styrofoam ("blueboard") and Owens Corning Foamular ("pinkboard"), insulates to R-5 per inch and is made with HFC-134a, which has a GWP of 1,430--meaning that it's 1,430 times as potent a greenhouse gas as carbon dioxide.

(I have to note here that I'm not 100% sure that XPS is made with HFC-134a; manufacturers are unwilling to divulge the exact blowing agents they use, saying the information is proprietary, and material safety data sheets have not been updated yet to reflect the new blowing agents that were required as of January 1, 2010. But various hints in technical literature have led me to believe that this is the blowing agent being used.)

The other insulation material made with a high-GWP blowing agent is closed-cell spray polyurethane foam (SPF). This insulation material is sprayed into building cavities, onto a foundation walls, or onto roofs, and it insulates to about R-6 per inch. Most, but not all, closed-cell SPF is made with HFC-245fa, which has a GWP of 1,030. Some closed-cell SPF is water-blown, thus avoiding this concern, though the vast majority is HFC-blown. Open-cell (low-density) SPF, such as Icynene, is all water-blown, so has a very low GWP.

01-04-12, 12:56 AM	#2
Nanie29 Lurking Renovator Join Date: Dec 2011 Location: london Posts: 2 Thanks: 0 Thanked 0 Times in 0 Posts	Can insulation materials, which we use to save energy and help prevent climate change, cause greenhouse gas emissions? Yes, in two ways. First, it takes energy to produce and ship these materials--which we refer to as "embodied energy"--and using fossil fuels for these energy needs releases carbon dioxide (our most significant greenhouse gas). So in a sense, all insulation materials have embodied global warming potential (GWP). Second, two of our common insulation materials are made with hydrofluorocarbon (HFC) blowing agents that are very potent greenhouse gases. Extruded polystyrene (XPS), best known by the brands Dow Styrofoam ("blueboard") and Owens Corning Foamular ("pinkboard"), insulates to R-5 per inch and is made with HFC-134a, which has a GWP of 1,430--meaning that it's 1,430 times as potent a greenhouse gas as carbon dioxide. (I have to note here that I'm not 100% sure that XPS is made with HFC-134a; manufacturers are unwilling to divulge the exact blowing agents they use, saying the information is proprietary, and material safety data sheets have not been updated yet to reflect the new blowing agents that were required as of January 1, 2010. But various hints in technical literature have led me to believe that this is the blowing agent being used.) The other insulation material made with a high-GWP blowing agent is closed-cell spray polyurethane foam (SPF). This insulation material is sprayed into building cavities, onto a foundation walls, or onto roofs, and it insulates to about R-6 per inch. Most, but not all, closed-cell SPF is made with HFC-245fa, which has a GWP of 1,030. Some closed-cell SPF is water-blown, thus avoiding this concern, though the vast majority is HFC-blown. Open-cell (low-density) SPF, such as Icynene, is all water-blown, so has a very low GWP.