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Is This The Right Roxul?

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by Trooper, May 4, 2013.

  1. Trooper

    Trooper Guest

    Hi folks,

    Looking to stuff some Roxul up the flue as during the installation of my insert. Is this the proper type to buy? Also, will it stay up in the flue without a blockoff plate?

    Thanks,
    Trooper

    Roxul.JPG

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  2. raybonz

    raybonz Minister of Fire

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  3. Dave A.

    Dave A. Minister of Fire

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    Oh %D..I! I got the Comfort Batt, didn't see Safe n' Sound at Lowes when I got it. But it says made from stone. The stuff I have doesn't pack in well like fiberglass, when people talk about stuffing it, what I have kind of breaks apart if you stress it anywhere, almost like compressed blown in cellulose. Is the safe n sound type different -- easier to use and/or made to withstand higher temps?
  4. raybonz

    raybonz Minister of Fire

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    http://www.roxul.com/residential/overview or http://www.roxul.com/products/products/technical+specifications

    This tells you what you need to know..
    Ray
  5. Dave A.

    Dave A. Minister of Fire

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    Thanks for the info, Ray.

    So at least the Comfort Batt is going to be as fire resistant as the Safe n Sound. The only question I have now is would the Safe n Sound handle any better. The Roxul site doesn't really answer that.

    I guess I'm asking for an observation from someone who's actually used the Roxul Safe n Sound. If you can actually pack it around something like the liner at the top of the chimney, stuffing it down with something like a stick without it actually breaking apart. The Roxul site says Safe n Sound is denser, so does that mean it's more resilient, tougher and doesn't tend to fall apart if you stress it?
  6. raybonz

    raybonz Minister of Fire

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    I would think so Dave but I haven't done this.. I would imagine anything in a batt form would be more rigid though..


    From FAQ's at Roxul site:

    Safe ‘n’ Sound™ is intended for acoustical and added fire resistance in interior wall applications. Interior walls have no R-value requirements so R-value information is not tracked or published for Safe ‘n’ Sound™. We recommend ComfortBatt® and ROXULPlus® be used in applications requiring thermal value.

    See bottom item Dave. Seems ComfortBatt and ROXULPlus should be used for your application..

    Ray
  7. Trooper

    Trooper Guest

    Thanks Dave and Ray. I believe I have fixed the attachment in my original post. I have the same question as Dave. I will be stuffing the Roxul around the liner up the flue at the bottom of the chimney, and maybe top-down as well.
    Has anyone done this and are there any tips/tricks you would like to share?
  8. Dave A.

    Dave A. Minister of Fire

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    I think they mean if you're looking for a stated R value as you would with insulating an exterior wall or attic. Safe n' sound isn't rated that way. They both seem to have the same fire resistance but Safe n' sound is better for sound insulation and it is described as "denser" 3" vs 3.5" thick and it is roughly 10% more expensive. I guess I should just go to HD and see if I see any packs of safe n sound that are open (the Roxul often are -- I had to pick through to find one that wasn't open -- and just see if it seems any tougher and doesn't break apart like what I have.

    Edit: Just curious why you picked the Safe n Sound at first -- has that been recommended previously here at hearth?
  9. raybonz

    raybonz Minister of Fire

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    No I noticed it was in batt form is the only reason but I think all Roxul will be safe as long as it is unfaced..

    Ray
  10. bag of hammers

    bag of hammers Minister of Fire

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    Agree. I've used both and AFAIK it's essentially the same material once you break it apart (the safe and sound is a bit more dense in the batt). I don't know much about stuffing roxul into a chimney around a liner, but I did take all the roxul scraps from my renos and stuff them into a few interior wall cavities just to use it all up (e.g. wall between shower and hallway - for a bit of soundproofing as opposed to throwing any away), so I imagine either batt would work for you. It's all fireproof.
  11. BrotherBart

    BrotherBart Hearth.com LLC Mid-Atlantic Division Staff Member

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    All Roxul is short fiber insulation so it breaks apart easily. That is also why I recommend wearing a mask when using it to keep from inhaling the fibers. Hasn't been shown to be carcinogenic but who wants a few hundred thousand fibers buried in their lungs?
    raybonz and ScotO like this.
  12. bag of hammers

    bag of hammers Minister of Fire

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    Compared to fiberglass it almost appears to be really "dusty" when working with it, but that's apparently the nature of those fibers. +1 on the mask for sure. A nuclear powered shop vac doesn't hurt either, when you're done...
  13. Sisu

    Sisu Feeling the Heat

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    Don't mean to be nitpicky, but if you are concerned about inhaling the fibres, make sure the shop vac is equipped with a HEPA filter. Otherwise, you are just recirculating the small fibres into the air and into your lungs.
  14. bag of hammers

    bag of hammers Minister of Fire

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    Not nitpicky at all. I also use dust bags with the filter (captures most of the crap, the filter takes care of the rest and lasts forever). You can't replace a set of lungs...
  15. ScotO

    ScotO Guest

    I used the comfortbatt in my chase installation, stuff is quite rigid and holds itself in between the studs tightly....
    That said, I agree on the dust mask. Even if it's been proven "safe" to breath, you don't want that crap in your lungs....
    And, for piece of mind, I did the 'redneck' test on it. Used a propane torch and held it against one side of the insulation, with my hand directly on the other side where the flame was hitting. Pretty amazing stuff. Insulation wouldn't burn, and my hand never got hot at all. For several minutes!
  16. bag of hammers

    bag of hammers Minister of Fire

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    Me too. Soldering some copper pipe and had some scrap pieces nearby and recalled seeing them do this on tv, so i figured "what the heck...".
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  17. TradEddie

    TradEddie Minister of Fire

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    I used the SafeNSound because it was all they had in stock at Lowes, it wasn't a problem for the block off plate. Later I bought some ComfortBatt for something else (Rim Joists), and it was noticeably less dense, and fell apart slightly more easily.
    One difference is that you can't claim a tax credit for the SafeNSound.

    TE
  18. Dave A.

    Dave A. Minister of Fire

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    So I guess I should try the SafeNSound especially if I want to work it around the top and bottom of the liner in the chimney -- I know the Comfort Batts would just break up and fall down. Now what to do with all of that extra insulation. Guess I can always lay down more in the attic (until I find another use) -- never have too much insulation there. :)
  19. bag of hammers

    bag of hammers Minister of Fire

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    I think as TE mentioned the comfort batts are "slightly" more apt to break apart, perhaps if you're stuffing the insulation in around the liner (no idea if that's how you'd actually approach the liner spaces) either type would be ok. There's a difference, but IMO it's not like the comfort batts just disintegrate as soon as you handle them. Just sayin that if the CBatts are the only option available, my guess is you'd be ok.

    I put any leftover full batts in the attic over the existing insulation, at the farthest corner of the house - as you say, you can never have too much insulation. Anywhere that you have a "thin" spot - over bath fan, etc. - good opportunity to add a bit more.
  20. TradEddie

    TradEddie Minister of Fire

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    Yes, the difference is very slight, I used the CB for my rim joist bays and it holds together just fine. Buy whichever is cheaper, remembering the tax credit for CB, nothing I saw would make me choose one over the other for functionality.

    Funny I also used the leftovers in the very same places...

    TE
  21. Dave A.

    Dave A. Minister of Fire

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    Not sure how to best approach it. I know that with my interior chimney the only exterior portion is the 5 feet above the roof line.

    That's the area which tends to be coldest and if there is any creosote it will form up there. So that was where I was planning to put the batts between the 6" liner and the 11x11 clay. I think there'll be enough compression on the batts to keep them from falling down if the batts don't break up.

    Then some others have mentioned insulating around the bottom of the chimney above the damper. But thinking again, it might be better for me not to do that so that any heat above the block off plate (and roxul covering the block-off) could travel up the chimney to warm the exterior of the liner.

    One problem I'll have is getting my SS chimney top fitting off. I sealed that to the top of the clay liner with silicone and then that fitting has a 2" lip with thumb screws that clamp against the clay tile that covers over that joint. I don't want to ruin that fitting (it was expensive). I'll have to use some kind of L-shaped piece of metal to fit in under the lip and break the silicone seal.
  22. bag of hammers

    bag of hammers Minister of Fire

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    If it's any consolation, they say the hallmark of good construction techniques is that what you build should be very hard to take apart later :) . Good luck with the overall project - hope it goes well...

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