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Community and Q&A

Spray Foam Insulation Incident – replace drywall?

NICMKE | Posted in General Questions on

Hi, we recently had some old batt insulation replaced with fiberglass blow in (below and above floorboards) in our attic. We’re in Milwaukee. Our contractor used spray foam to do some air sealing, but the spray foam didn’t mix correctly and component B (polyol and tetraflourethane) sprayed  onto the back side of the dry wall of our bathroom, and even sprayed through some of the plumbing entrances in the bathroom, which leaked down our wall, shelving and pooled on a shelf in the vanity.

The contractor wiped up what was in the bathroom, but we’re concerned with the health issues of having this liquid which we assume absorbed into our drywall and back side of our shelving on the other side of our bathroom. From what I’ve read, when SPF doesn’t correctly mix and the chemicals don’t cure, this can be a concern. We read the MSDS and it instructs that cleaning must take place in buckets, and of course it doesn’t mention anything about cleaning it from permeable surfaces such as drywall or lumber.

The contractor and manufacturer tried to ensure us that the component that our bathroom was exposed to is safe, and that the other component would have been problematic.

We don’t smell any odors, but we’re still concerned about the uncured chemical and we’re considering having the drywall and shelving replaced. Are we overreacting?

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  1. DC_Contrarian | | #1

    Do you have a link to the MSDS? We might be able to help you interpret it.

    1. NICMKE | | #4

      Hi DCContrarian, I'm attaching the MSDS in two separate files, component A and B. Component B is the component that didn't mix. Thanks for your help.

  2. Expert Member
    BILL WICHERS | | #2

    Personally, I would get the contractor to fix this and not just go with "it's safe". You have other issues here besides safety, which include damage to interior finishes. This is the kind of screwup that insurance is there to deal with, so you may have a claim against the contractor's insurance. You'll probably end up needing to replace some drywall, and also paint. I wouldn't paint over the blue stuff, you'll need to either thoroughly clean it, or just replace those sections of trim that are contaminated.

    If a contractor does work that damages something else in the house, then sometimes the contractor will just fix it themselves -- and I'd give them the chance. Contractor's generally don't like claims againt their insurance, since it can raise their rates, and I'd give them the chance to just fix things themselves, possibly by contracting it out. If they don't, or try to dissapear, then it's insurance claim time. Give them the chance to make it right first though.


    1. NICMKE | | #5

      Thanks Bill - this is very helpful.

  3. Expert Member
    Akos | | #3

    That needs to be removed, what you see is the tip of the iceberg, it will be a mess inside the wall. Hard lesson but two part spray foam is unforgiving, if you mess it up, you have a very expensive cleanup.

    You won't be able to get the material out of the studs, the best way to deal with it is to spray of a thin layer of properly mixed spray foam over it. The polyol will react with the iso in the mix. The mix will still be off but at least you won't have the unreacted material lingering.

    1. NICMKE | | #6

      Thanks - this is also very helpful.

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