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Spray foam odor

cproberts | Posted in GBA Pro Help on

Spray foam installed Aug 12 2019. We have had odor upstairs since day 1. They did not vent properly during installation. They can cut holes in foam,put fans to move air for 4 weeks. Did not work. Then said old loose insulation and batting was causing reaction. They removed all other insulation. Air quality test done. 1200ng VOC gases. I now have RADS from VOC gases . Extremely sensitive to most All smells. Now they installed a ERV with ultraviolet and smell is still there mostly inattic and storage space off attic. We re at wits end. Toxic envelope

. Help!!!!!!

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  1. user-2310254 | | #1

    If your foam was installed properly but residential odor is a problem, you may need more mechanical ventilation to pressurize the structure. But before spending a bunch of money, you probably should call in someone who has experience diagnosing this type of issue. It sounds like the contractor is trying to resolve things, but a RESNET rater might be able to help you find an effective solution.

  2. Expert Member
    BILL WICHERS | | #2

    I don’t buy the “old insulation is causing a reaction” argument. I suppose this MIGHT be possible, but I’ve never seen it. It’s common to stuff fiberglass or mineral wool in voids to use as a backer for spray foam, so it’s not as if it’s a problem for spray foam to contact batts.

    What you need is flow-through type ventilation over a period of at least several days. Open windows at opposite ends of the space that was spray foamed. Put some box fans in one end blowing OUT. This will do two things:
    1- slightly depressurize the space to suck any smells out and keep things from leaking into other areas
    2- flow fresh air through the entire space to air it out.

    Leave this setup running continuously for at least a few days. I usually recommend “over the weekend”. See if that improves things. Oftentimes all you need is a few days of ventilation and things get better and stay better.


  3. severaltypesofnerd | | #3

    Definitely check your contractor's licence, and their performance bond (their insurance).
    What was the temperature on the day of install?
    Could you upload air quality test results?
    What's the control or outside air quality like? What's the basement like? The attic?

    1. Expert Member
      BILL WICHERS | | #5

      A performance bond is not the same as liability insurance.

      Liability insurance, as is what contractors typically have as the “insured” part of “licensed and insured” typically covers damage they might cause during a project, or damage related to work that they did. There’s a lot more to it, but that’s the basics: insurance pays for stuff they break while they are working on your project.

      A performance bond is a special insurance product that is an insurance company backing up the contractor to guarantee the contractor completes a project. These are then “bonded projects”. If the contractor fails to complete the project, the insurance company that issued the performance bond pays for a different contractor to come in and complete the original project.

      Typically if a project is completed, but something is damaged, it’s covered by liability insurance. If the contractor disappears without completing a project, a performance bonds pays someone else to complete the job.

      I have required performance bonds from subcontractors bidding on projects for me. The last time I did, it was because the contractor I selected was about 1/2 the price of the other bids I received. Usually lowball bids are a warning sign, but in this case I knew the contractor and had done many other projects with them so I trusted them. I did make them get a performance bond though to protect my project just in case.

      Any licensed contractor should also be insured. Such a contractor should be able to provide their “insurance cert” on request, and it will come from their insurance company, not from the contractor. You’ll get an “accord form” that will list all the dollar limits for the coverage your contractor has.

      I’m not sure if you would be able to make a claim against the contractors liability insurance policy in the case of smelly spray foam, unless maybe if it’s a really bad (incorrect chemical mix, fails 3rd party safety testing, something like that). You can ask your contractor, and if they are resistant to that AND don’t want to help you, try calling their insurance company and asking them. Putting claims through can be difficult though since the insurance companies don’t like to pay out unless they have to. You may end up needing a lawyer for something like this.

      I would try filing an insurance claim as a last resort, always try the friendly way first working through the problem with your contractor.


      1. severaltypesofnerd | | #6

        Note that spray foam has been the cause of a number of big insurance payouts.

  4. bigrig | | #4

    In addition, how much insulation did you have installed (inches) and how many layers/passes did they take?

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