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Foam insulation

Bershire_KJ | Posted in General Questions on

I recently bought a house in the Berkshires that has a crawlspace (part cement floor, part rock ledge, part dirt floor).  The previous owner had foam insulation installed in part of the crawl floor ceiling (not sure when — probably several years ago).
I don’t know if the foam was properly installed (it doesn’t look professionally done), and it covers some pipes. I’m concerned about possible off-gassing & air quality as well as the possibility of hidden moisture issues.

I have two questions:

— Are these concerns justified? 
— Is there a way to safely remove the foam insulation and replace it with something less environmentally hazardous?

Thank you for your expert advice.

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  1. Expert Member
    BILL WICHERS | | #1

    Is it spray foam or rigid foam board? If it's rigid foam board, I doubt you'll have any issues with offgassing, but you could potentially have moisture issues depending on how the work was done. Rigid foam board isn't usually all that difficult to remove though -- you can sometimes just remove a few fasteners and take out entire sheets intact, other times you can break it up and take out chunks similar to how you'd demo old drywall.

    If it's spray foam, and it was installed years ago, you probably don't have any offgassing to worry about. One nice thing with spray foam is that any problems tend to show up immediately after install (as in within a few days at most), problems don't typically show up years later. You could have moisture issues depending on how the work was done, and if you do, the downside to sprayfoam is that it is *much* more difficult to remove.

    Basically I don't think you're likely to have any issues with offgassing if the work was done years ago, but you might want to check that things were done correctly and there aren't any potential moisture issues. Can you post a few pics of the install? It's hard to really give you much of an opinion on the installation without seeing it, or at least having things explained in a lot more detail.


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