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When polystyrene foam insulation was removed from GreenSpec in Sep ’09, why were ICFs and SIPs exceptions?

jtholt1 | Posted in Green Products and Materials on

Also, GreenPrints (Mar ’10) claims that “EBN is working with USGBC to prevent the use of foam plastics insulation inside of buildings and above ground uses and will only be approved for below ground insulation.”

Why were ICFs and SIPs exceptions since both are used above ground?

Also, does GBA believe it is realistic to make significant progress in deep-energy retrofits in the next decade without the use of affordable polystyrene foam insulation?

Thanks in advance for your responses.

Best regards,
Tim Holt

GBA Prime

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  1. Riversong | | #1


    I'm very surprised that the "Green" building movement is finally realizing the illogic of using petrochemical materials to save petrochemical fuels, but it's about time. I've been advocating this sane approach for 30 years.

    Are they suggesting the elimination only of above-grade polystyrene and not spray urethane and polyisocyanurate foams?

    And I'd like to know what they're suggesting as alternatives.

  2. jtholt1 | | #2

    Actually, I'm not in favor of the work to eliminate rigid foam insulations. Hope we can still have a friendly exchange. The data being presented against them is very shallow and in the earliest stages of analysis. That said, if the final analysis shows that the materials must be modified, then the manufacturers should be allowed time to find and test commercially viable alternatives. In my opinion, it will be very difficult to build and retrofit for energy efficiency without the use of affordable, durable rigid plastic foams. My question about using SIPs and ICFs above ground was intended to learn about the rationale. It seems inconsistent to remove PS foam insulation from GreenSpec with those products as exceptions.

  3. GBA Editor
    Martin Holladay | | #3

    I'm not sure that GBA has a single voice, but I'll address your last question.

    Making "significant progress in deep-energy retrofits" will depend on a fundamental change in today's economic realities. I'm not sure what might happen to facilitate more deep-energy retrofits, but it might be a combination of huge energy price increases, high carbon taxes, or very generous government incentives. Failing that, nobody is going to see "significant progress in deep-energy retrofits" any time soon.

    It is certainly possible to perform deep-energy retrofits without polystyrene insulation, using polyisocyanurate, cellulose, mineral wool, or some combination of all three.

  4. wjrobinson | | #4

    Great topic... I am totally for existence less fossil fuel.

    A friend in Cambridge NY... where I take care of clay tennis courts is the advisor to an RPI project to make non fossil organic foam. I have been watching the progress over the years and am proud of all involved. So cool.


    There is also soy foam... Demilic is one ....

    and there is thousands of sqft of used foam available. Used foam is 100% 0 carbon in my mind. Even better than all other foams as it is not adding costs to society to be disposed of.

  5. Alex Wilson | | #5

    It is true that we have various concerns about polystyrene. All polystyrene insulation today contains the brominated flame retardant HBCD, which is being targeted by health and environmental advocates as a chemical to avoid. And extruded polystyrene (XPS) is made with an HFC blowing agent that has a high global warming potential. For more on the latter concern, see my blog post on it:

    While we no longer consider polystyrene a "green" material, we opted to keep SIP and ICF products in the GreenSpec directory, at least for now, because, in our opinion, the system-related energy-performance benefits counteract, at least to some extent, the negatives associated with the chemical constituents. We have, however, removed several XPS SIPs from GreenSpec, because of the combined concerns of HBCD flame retardant and the GWP issue.

    I don't know what is meant by the comment that "EBN is working with USGBC to prevent the use of foam plastics insulation inside of buildings and above ground uses and will only be approved for below ground insulation." I spoke at Greenprints this past March and addressed our concerns about polystyrene, but I did not say that we want to prevent the use of foam plastics from building interiors, and we're certainly not working with the USGBC on such an agenda. Our goal as a publication and a company is to provide users with the best information available to help the design and construction community make wise decisions regarding environmentally responsible building.

    -Alex Wilson, Executive Editor of Environmental Building News and GreenSpec (BuildingGreen, LLC)

  6. Sam Rangel | | #6

    "Green-Washing" has unfortunately run rampant. The first sentence of the NYC "Cool Roof" initiative is: [NYC °Cool Roof is a green initiative to reduce energy costs, greenhouse gas emissions, and
    local temperatures by coating the roofs white]. Two of the three available products for this initiative are so high in VOCs, they're not allowed to be sold in California. The product with the least VOCs has 54 g/l. How "Green" is that??? The standard for "Green" should be: Green at the point of manufacturing; Green at the point of application; and Green at the point of removal. That's what "Green" should mean.

  7. Riversong | | #7

    The standard for "Green" should be: Green at the point of manufacturing; Green at the point of application; and Green at the point of removal. That's what "Green" should mean.

    That's an extensive definition of a "green" product, but a completely useless one, since it fails to first define the term "green". And it's exactly this ambiguity and vagueness about "green" that allows anyone to use it in any way they choose - hence "green-washing".

    Do you mean "non-toxic" (toxic to whom?), "non-injurious" to both present and future generations" (of humans only?), non-harmful" to the biosphere (do all species have the same standing as humans?).

    And is it enough to define "green" by what it's not? Most harmful products don't exhibit their consequences for some time, and our knowledge of the complex living world is so limited that we often cannot foresee those consequences.

    Perhaps "bio-mimicry" comes closest to a positive understanding of "green", in that technological procedures and products that approximate what Nature has sustainably created for 3.7 billion years are the most likely to be benign.

    In truth, "green" has to mean something far more fundamental, and hence radical, than almost every current usage before we can claim to be building a sustainable or regenerative human culture. And it has to mean far more than merely a quality of products and procedures, since Nature's economy (synonymous with ecology) is mostly based on relationships and those relationships are primarily local and cooperative and egalitarian and communal (every member of the 50 trillion cell community that is your body gets all the nutrients it needs before any "wealth" is stored for later collective benefit and any cell that benefits at the expense of others is a cancer).

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