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Zonolite vermiculite for SS liner?

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by nola mike, Nov 5, 2010.

  1. nola mike

    nola mike Feeling the Heat

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    Looking at the zonolite insulation on this page:
    http://www.masonpro.com/insulation.htm

    to insulate the space around my 6" SS liner that I just installed within my 9" factory built chimney. This is the only stuff that I can find locally. Will this work?

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  2. pgmr

    pgmr Feeling the Heat

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    Should be fine. I'd also suggest looking at garden centers. They often carry both vermiculite and perlite. Perlite will absorb less moisture than vermiculite. Get the coarsest stuff you can find and seal the gap around your lower block off plate with door seal, fiberglass, etc. The fines will find their way through if you don't.
  3. roadcone

    roadcone New Member

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    6 parts vermiculite and 1 part portland makes a good mix
  4. pen

    pen There are some who call me...mod. Staff Member

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    just don't buy the miracle grow vermiculite w/ the the fertilizer in it already.

    pen
  5. nola mike

    nola mike Feeling the Heat

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    OK, so upon further review they don't have it. What I have found at the garden center is either vermiculite or perlite in 2 cu ft bags.

    1) is one preferable to the other?
    2) i saw a mention of mixing it with portland cement...what then? Am I just throwing this stuff down dry, or mixing it with water, or what?
  6. roadcone

    roadcone New Member

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    6 parts vermiculite for 1 part portland. dry mix both together (in a wheelbarrow with a hoe) then start to add water. Add water till mix starts to get damp ( Grab a handful and squeeze when the mix holds together thats enough water) use that as your insulation. It will insulate and stiffen but allow for the liner to move with expansion while still holding together. I use this mixture for the liners aswell as the insulation barrier around the fire brick inside wood fired bake ovens. Allows the entire firebrick oven to heat up and expand and holds all the heat inside. as it cools the mixture contracts with the oven and chimney liner.
  7. roadcone

    roadcone New Member

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    Oh and looking back at post I see this is in a pre-fab chimney. Just be careful you dont need the airspace in the chimney required for the pre-fab to still be listed and current on nfpa standards.
  8. nola mike

    nola mike Feeling the Heat

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    the airspace is outside of the prefab--this is just filling in the space between the original inner wall and the new liner.
  9. Northeaster1

    Northeaster1 New Member

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    Roadcone - I was considering pouring either loose vermiculite, or a mixtire of vermiculite and portland cement, for example, into the air space between my solid SS liner and the 12"x12" clay liner, at the house. But, as I read the instructions to install another solid liner (selkirk versa-liner) at our summer house, the instructions said not to pour either loosed or cemented insulation materials. It only recommended using a 1/2" foil backed type of insulation. As I wanted t omake sure i was up to code, and figured that going against the manufacterer's instructions may not be good, I bought the recommended type.

    Could you give a bit more info as to the type / brand of liner use install with poured in Vermiculite, and whether or not it says that is OK in the instructions. I am asking as I am still considering if I should insulate the liner at our house, as it is an external chimney, but it is a versa-liner as well, so they recommend against the pour in..
  10. roadcone

    roadcone New Member

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    Selkirk is a Canadian company, Canadian code is to not fill air space with insulation on any stainless reline witch is why it states this. NFPA 211 Code states to Either use a 1/2 Blanket or use a poured insulation that will be at least 1 inch thick around liner on all free standing solid fuel burning appliances.
    A couple liners to install with poured insulation would be forever flex, or armor flex.
  11. Northeaster1

    Northeaster1 New Member

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    Thanks for the info!! Makes sense. I do think that it would be safe, of course, to use a pour in material. But, I would not want to add something that goes against either code, or the manufacturer's instructions, for fear that it could be used against me, by the insurance so, if there ever was a fire.

    Thanks for the clarification!
  12. branchburner

    branchburner Minister of Fire

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    But does the poured insulation need to be an approved pre-mixed brand, or is homebrew acceptable? I'm not questioning your recipe, sounds great, but only questioning whether the liner manufacturer actually lists a home-made pour-in mix as a possible insulation alternative.

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