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Community and Q&A

Insulating Large Void in Attic

suect | Posted in General Questions on

I noticed with the weather changing a cool section in my attic.  Using an Basic infrared Tool and app on my phone, I pointed it to an angled ceiling in my kitchen that is approximately 3 x 28 feet.  The camera definitely shows a difference in color from other areas.

I have done reading that states not to fill voids with foam.  Could pink fiberglass blow in insulation be used in this cavity?

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  1. Expert Member
    Dana Dorsett | | #1

    If it's a catheralize ceiling, no, blown fiberglass would be too risky in your climate zone.

    If it's on a sun exposed south facing pitch you could probably get away with blown cellulose, even though it's technically a code violation.

    Do you have soffit to ridge venting on that roof pitch?

    1. suect | | #2

      This is a north facing wall. There are no vents in the soffits or ridge due to completely foamed attic. Somehow this section was missed and I’m searching ways to correct this.

      I noticed a lot of humidity where the warm south meets the cool north in the attic.

      Any suggestions? Thank you’

  2. Expert Member
    Dana Dorsett | | #3

    How deep are the rafters in that section?

  3. suect | | #4

    I’m not sure as most are under foam from the top attic view. Can see a small gap the length where the angled ceiling meets the flat ceiling. I believe someone may have stated 4” Board but was referring to the side walls in the attic that run perpendicular to the flat ceiling.

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