Attic insulation question

Ben
by Ben
In my attic, I currently have a 4-5" of vermiculite insulation between 2x6 joists. Above that is a layer of tar paper stapled to the top of the joists. I want to add a layer of batt insulation above that. Seems like I would need to fill in the small gap between the vermiculite and the tar paper before adding the batts. I am wondering if it is ok to remove the tar paper to do so? I will likely need to damage it some amount in any case. Will I need to replace this with some other kind of vapor barrier if I do?
  3 answers
  • William William on Dec 09, 2016

    The problem with Vermiculite insulation is that it may have harmful amounts of Asbestos in it. Check out the link.The tar paper you have is not a vapor barrier, but its to keep the Vermiculite from being disturbed. Wear gloves, long sleeves, gloves, eye protection, and dust mask. Remove the tar paper, try to limit disturbing the Vermiculite. Fill the gap between the Vermiculite and the top of joists with foam sheet insulation to seal the Vermiculite even with the top of the joists. Then you can install fiberglass batts yourself right over existing insulation, but follow these precautions Make sure you use an unfaced batt (one without a paper or foil layer) so the insulation does not trap moisture in the ceiling. Lay the batts perpendicular to the joists so they do not compress the insulation below. Don't cover can lights unless they are rated for contact with insulation. It's safer to build a small enclosure with hardware cloth or plywood to keep loose insulation away from lights and exhaust fans. Use cardboard or rigid-foam baffles to keep soffit vents open. Fill all cracks between the living area and the attic with caulk or expanding foam. You do not need to install a vapor barrier or it will trap moisture in the ceiling. ***** http://structuretech1.com/new-information-vermiculite-attic-insulation/"

  • Ljgordon Ljgordon on Dec 11, 2016

    I would be concerned that the inch or so between the vermiculite and the tar paper would allow air movement. Since the tar paper is not a vapor barrier, I would use a utility knife and cut along the inside of each 2x6 and let it fall onto the vermiculite to help seal in the asbestos. Lay the unfaced insulation between the 2x6 and lay the second layer perpendicular to the first. You need to find out what is the minimum attic insulation in hour area.Ditto William's suggestion about the lights.

  • RichandTammy Whiteside RichandTammy Whiteside on Dec 12, 2016

    You HAVE to remove the vermiculite. It is not worth the health risk to you or to anybody who purchases your home should you decide to sell it. You really need to check out the link that William supplied. There is money available to assist you with the removal of the vermiculite. My father headed the asbestos abatement for a local school district and pretty much everybody in his department (including himself at the ripe old age of 56) died of lung cancer.