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Overblown insulation

joenorm | Posted in General Questions on

I had my walls done in blown-in fiberglass.  I thought they did a great job, no voids and quite densely packed. The stud bays are noticeably “pillowed” out but I can go through and pack it pretty flat with little effort.

But the drywallers hate it. They say its a problem every time they do a job with blown-in. I told them all they have to do is push on it a bit but their response is “that’s not my job,” so naturally I’ve been doing it for them. They spec’d 5/8 for the whole house after seeing the insulation(OK with me).

They said normally they remove the excess but I was pretty clear I wanted to avoid that.

So my question is this: Is it normal for the insulation to pillow a bit like this? Did the insulators over-blow or are the drywall guys just lazy about dealing with it?

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  1. Expert Member
    ARMANDO COBO | | #1

    The simple solution is for the blown insulation installers to roll it, that's in the installation instructions, but too often is ignored due to laziness, ignorance or plain fraud. The drywall installers are correct, its not their job, but I would not allow them to remove any insulation either. We also use 5/8" drywall throughout, walls and ceilings.

    1. Expert Member
      RICHARD EVANS | | #2


      Just curious, why do you like 5/8 drywall on walls? Does it complicate door jambs? Always enjoy your wisdom on GBA.

      (Sorry Joe for hijacking your question...I couldn't resist)

    2. Expert Member
      ARMANDO COBO | | #3

      I specify 2x6 @ 24”o.c. walls, built with finger jointed studs, and LVL studs for tall wall designs. The 5/8” drywall allows for straighter walls, better sound attenuation and fire rating, which it could help with insurance. Level 5 drywall finish is easier to achieve as well.
      Assuming the walls are perfectly plumb, the jamb size is 6 7/8” wide, costing around $25-40 more for each door, or you could also add a 1/4" trim strip, glued and tacked, to the side with no hinges nor strike plates, depending on the finish. Good trim carpenters are always “adjusting” door jambs due to walls, sheathing or drywall that are not flush or straight anyways.
      I almost forgot, adjusting jambs with outsulation, and/or window bucks deal with the same issues.

      1. Expert Member
        RICHARD EVANS | | #4

        Thanks Armando! Great stuff. I hope your clients appreciate the value you are bringing to their projects.

      2. Expert Member
        ARMANDO COBO | | #5

        Me too, thanks ;-))

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