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Community and Q&A

Dense-Packed Cellulose in Basement Ceiling

rhl_ | Posted in General Questions on


We are closing up our basement, it has floor heat so we want to install insulation in the floor.

I want to do an over and above job, so i am interested in speccing out dense pack cellulose.

The installer said to put the drywall up we would need to use a product like this:

Wall Roller

and i should find an installer with experience doing this.

I’m curious if this is feasible or abnormally harder on a ceiling?

And yes i know that we probably dont need to use dense pack.

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  1. Expert Member


    Does filling the joist cavities give you the optimum amount of insulation for a floor separating two conditioned areas?

    Dense pack cellulose R 4.0 per inch.
    High density fiberglass batts R 4.2 per inch.

    1. Expert Member
      NICK KEENAN | | #2

      Yeah, I don't get dense-pack in this application instead of just batts. Floor joists are typically 10 or 12 inches, you can fit way more insulation than you'll need. R-13 is probably enough, all it's doing is keeping one zone from influencing another too much.

  2. rhl_ | | #3

    Mice can’t go through the dense pack is the reason.

    1. Expert Member
      NICK KEENAN | | #4

      Not my experience. They tunnel right through it.

    2. Expert Member
      Michael Maines | | #5

      Mice can go through dense-packed cellulose. The typical borate additive makes them somewhat averse, and if the density is very high it could help dissuade them. But I rarely see densities that high. I would find another method of pest control. But there's no reason why dense-pack wouldn't work in the ceiling. Here in New England we usually strap ceilings, and I would recommend it for any ceiling. I recently tried skipping the strapping on a dense-packed ceiling finished with wood boards and wish I had taken the extra effort to install strapping.

      1. rhl_ | | #6

        What do you mean by strapping?

        I guess this is kind of overkill your right .

        Probably better for maintence to leave a few inches to store pipes etc.

        1. Expert Member
          NICK KEENAN | | #7

          In New England it's customary to run 1x3 or 1x4 strips perpendicular to the joists on a ceiling and attach the drywall to those pieces. Those pieces are called strapping.

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