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  1. GBA Editor
    Martin Holladay | | #1

    I have not heard any reports of problems associated with off-gassing from XPS. By the time it reaches the job site, the foam is fully cured.

    Remember, there is no reason for any XPS to be exposed in a home (with the possible exception of rim-joist areas). Ideally, all of the XPS in your home will be covered with gypsum wallboard, concrete, or some similar air barrier.

  2. SRReynolds | | #2

    GreenGuard certifies only the Corning Foamular XPS as meeting its indoor air quality standards - FOAMULAR® insulation is also the only extruded
    polystyrene product certifi ed by the GREENGUARD
    Environmental Institute’s GREENGUARD Children
    and Schools Product Certifi cation under the
    GREENGUARD Standard for Low Emitting Products.4
    GREENGUARD certifi cation means that certifi ed
    Owens Corning products contribute to indoor
    air quality. - but does not certify any Dow products. Does anybody know the reason?

  3. cellulosefacts | | #3

    Martin, "Haven't heard" is not a decisive answer. Let me enlighten you. It burns! The by-products of combustion are gasses. They are poisonous.

    1. Trevor_Lambert | | #4

      Everyone knows that XPS burns. It's also obvious that anything burning produces gasses, almost always toxic. You have enlightened no one. It's pretty obvious that Steve was asking about off-gassing in normal use. So your answer, while decisive, was less helpful and less honest than the answer Martin gave.

  4. cellulosefacts | | #5

    Trevor, are you stalking me? "Everyone" doesn't know it burns. Marten said he never heard of any problems with foam off-gassing so I cited the data every consumer should know. Are you claiming Martin put foam in his new house knowing the foam would burn and likely kill him in the event of a fire? Burning foam does serious off-gassing.

    1. Trevor_Lambert | | #6

      I promise this will be the last time I respond to you.

      As I said, the context of the off-gassing that everyone else understood was off-gassing in normal use. Otherwise he would have asked, "if my house burns down, is the XPS going to off-gas"?

      I have no idea whether Martin has XPS or any other foam in his house or not. I am fairly confident that he is aware that polystyrene in all its forms is capable of burning, and will emit noxious fumes. I don't know a single person over the age of 6 who is unaware that the burning of just about any plastic produces noxious fumes.

    2. severaltypesofnerd | | #10

      Foam burns.
      It's called a tradeoff.

      Want to see a similar type of foam burning FAST?

      A warehouse storing EPE foam burst into flames after a worker ignited highly flammable foam rolls with a lighter in southern China’s Guangdong province.

  5. cellulosefacts | | #7

    Again, lots of folks are misled by salesmen, web stories, etc so don't know much about foam. It doesn't mean they are dumb or under the age of six!

    Off-gassing is not normal for the human's a big thing. Martin should point that out. Stories written about the benefits of various foam formulations are often exaggerated, and as Martin exemplifies, the downside ..the DANGER isn't pointed out. If foam is mentioned the warnings should also be filling a prescription and getting the side effects..." in some cases this will kill you." Think a little, Trevor. You might enjoy it.

    I don't care if you post to me, about me, whatever, just think a little.

  6. Jon_R | | #8

    VOC is such a generic term - people and house plants emit VOCs. Don't worry about VOCs - worry about specific VOCs.

    XPS off gases very very slightly - which is why it's R value drops over time. But the chemical is considered so harmless to humans that it's used in inhalers.

    1. Expert Member
      Dana Dorsett | | #9

      Yeah, but if you set the inhaler on fire it's downright dangerous! :-)

      (Oh yeah, the HFCs make it almost impossible to set the inhaler on fire, unlike XPS...)

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