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Roofing materials offgassing: toxicity question

DIPolojarvi | Posted in General Questions on

Hello, I am having my 1850s house reroofed. The roofers put a layer of OSB over old board sheathing to create a nailable surface. Then they put a layer of ProArmour synthetic underlayment and IKO Armourgard ice and water shield over the OSB. Shingles are  IKO Cambridge Dual Black shingles. The smell in the attic is truly unbelievable now. Seems like a toxic nightmare. I had sprayfoamed the ceiling and rafters with closedcell foam about 7 years ago, and it seems unlikely that is causing the smell. The house is a typical 1850s add-on arrangement, and the roofer finished the main house roof this week. They’ll be moving on to the smaller portion next week (which is right next to the bedroom windows of the bigger part of the house). Any information you could share would be most welcome. I wrote an earlier post about this, thinking it might be the foam. Sorry for any confusion. Ilmari

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  1. Expert Member
    BILL WICHERS | | #1

    There was another post about this same issue just recently. If your house is well air sealed from the attic as it should be, anything in the attic shouldn’t enter your hose so you should be relatively safe. Hopefully whatever you’re smelling will only off gas for a short period of time (a few days or so) and then the smell will dissipate.

    Note that hot weather will hasten any off gassing, so you’ll smell it more but it will end sooner.


  2. GBA Editor
    Martin Holladay | | #2

    In general, it's best to post any follow-up questions as new comments on your original thread (rather than creating a new Q&A thread with a follow-up question). Interested GBA readers can find Ilmari's original question here: "Spray foam off-gassing after new roof was installed."

    1. DIPolojarvi | | #3

      Will do, Martin, thanks.

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