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Possible to dense pack cellulose by hand?

Gainsolarman| Posted inGeneral Questionson

Zone 3a/4a right on the line….

I am renovating an 1870’s balloon framed farmhouse. I am residing the house and thus opening it up from the exterior. Doing this one wall section at a time. While I have the walls open I am insulating from the outside. I hate fiberglass. I’ve already successfully dense packed a number of the wall cavities with the following method….

1. rip plywood in 2×8 sheets and fasten longways to wall.
2. hand pour/pack cellulose in cavities
3. tamp with 2×4 until tightly packed/cant pack anymore
4.我计算了立方墙上c的镜头avities as I go and comparing to # of bales of insulation ive used and I’m averaging aroud 4 lbs per cubic foot

What is wrong with doing it this way other than it being time consuming?
我遗漏了什么东西?

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Replies

  1. Expert Member
    Dana Dorsett||#1

    >"2. hand pour/pack cellulose in cavities
    3. tamp with 2×4 until tightly packed/cant pack anymore
    4.我计算了立方墙上c的镜头avities as I go and comparing to # of bales of insulation ive used and I’m averaging aroud 4 lbs per cubic foot"

    4lbs is a density beyond where it's R/inch will be going down, not up, and won't be as consistent, but it's way better than nothing. The sweet spot for cellulose performance is an even-density( not lumpy) 2.8-3.2.bs, though in colder climates 3.5lbs may be necessary to prevent settling in 2x6 wall cavities. In zone 3A something like 3-3.2lbs would be enough.

    It's possible to dense pack to 2.8lbs+ with a single stage rental blower if there is enough room to fish the hose all the way up or down into the cavity, though it's easier using narrower 1-1.25" I.D. dense packing tubes. With a balloon frame you'd have to install air barriers on the open cavity tops (and bottoms, if open). Corrugated cardboard stapled to the framing with a X cut into it for inserting the dense packing tube can work pretty well when dense-packing to less than 3.5lbs.

    Don't rule out "2- hole method" lower density cellulose, which usually ends up around 2-2.5 lbs. If lower density cellulose settles over a decade or so it can be topped off. On a full-gut rehab project I've seen 2-hole method cellulose that hadn't sagged a bit in a 2.5 story balloon frame 30 years after installation. It looked like it could have been installed 30 hours (rather than years) prior.

  2. Tim R||#2

    I hand installed cellulose in rafter bays from the top. - I put the cellulose in a large box, then used a drywall compound mixer on a drill to fluff the insulation prior to installation. I got very close to the volume listed on the bag.

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