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Community and Q&A

Rigid foam scraps under cellulose in attic?

Adam Emter - Zone 7a | Posted in Green Building Techniques on

I have ~300 square feet of rigid foam scraps (mostly EPS and XPS) from my building project and I hate to see them in the dumpster. Is there any reason why I shouldn’t put the scraps above the ceiling drywall, between the truss chords, before I blow in cellulose?

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  1. GBA Editor
    Martin Holladay | | #1

    I can't think of any reason why you can't due what you propose (as long as the rigid foam isn't exposed; remember that exposed rigid foam is a fire hazard).

    However, I doubt whether the added foam scraps will change the R-value of your insulation layer. The volume of displaced cellulose will be small, with little economic value.

  2. Adam Emter - Zone 7a | | #2

    Thanks for the reply, Martin. I know it won't add much r-value, but it just seems like a shame to put it in the dumpster. I'm trying to use and re-use as much building materials as possible instead of them winding up in the landfill.

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