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How does an "Insulate" differ from a block off plate?

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by lumbering on, Feb 7, 2013.

  1. lumbering on

    lumbering on Feeling the Heat

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    I just called my installer, who just put the stove in a few months ago. He can't confirm if there is a top cap plate or if he insulated at the top, and wants to charge a service fee to check this out. I'm not climbing up 3 stories to check on my own. I guess I'll wait till I get it swept this spring.

    Meanwhile, they don't install block off plates. Instead they want to install an "insulate". I'm not sure if he just means stuff it with insulation, or if there is a separate device that the industry refers to as an "insulate"?

    And who should I look to for a block off plate? Do installers typically do this?

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  2. lumbering on

    lumbering on Feeling the Heat

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    To clarify I have a free standing stove in an existing masonry fireplace
  3. KaptJaq

    KaptJaq Minister of Fire

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    Never heard an installer do an "insulate" before. I would guess you are right and he wants to stuff the bottom of the flue with mineral wool to stop the airflow. Since every block-off plate is different they require some custom work with sheet metal. Most installers would prefer not to be involved with this type work.

    Stuffing the bottom with mineral fiber is a lot better than nothing. A block-off plate is better. Most DIY installs have the mineral fiber and the block off plate.

    If your stove is free standing and you can get behind it to see the flue you can see if there is anything around the stainless steel liner. If you can see past the old damper opening and up alongside the liner you should probably do something.

    Get some Roxul mineral fiber insulation and stuff it up along side the liner. Pack it as far up as you can. If you need to you can use strips of sheet metal to create a block off plate. What I have done is pushed the Roxul up then overlapped a number of metal strips just above the old damper frame. They are held in place by the weight of the Roxul.

    I would guess there is some type cap on the top otherwise you would be getting rain alongside your liner. How well it is sealed or insulated is another question. If your installer does not know what he did I would probably find a sweep from a different company to check it out and do what is necessary.

    KaptJaq
  4. Heatsource

    Heatsource Minister of Fire

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    adding insulation blanket, wraping the pipe. many systems require it for proper ul listing

    pretty lame the installer cant recall what he installed!
  5. KaptJaq

    KaptJaq Minister of Fire

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    Yes, but the installer wants to install an "insulate" instead of a block-off plate. Insulating the liner is not going to prevent the heat from escaping up the flue outside the liner unless he completely fills the gap. The liner should have been insulated at the time of the install if it was required for proper UL listing. His invoice should also specify exactly what he did to be presented to the local authorities if needed. Therefore my comment to find a sweep from another company...

    KaptJaq
  6. webby3650

    webby3650 Master of Fire

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    I'm not sure why this guy doesn't keep records. Just take a look at the damper area. It would be immediately noticeable if there was insulation stuffed in there. He doesn't know if it has a top plate, or if he insulated at the top?? He should have some sort of standard practice.
    He sounds pretty unprofessional, I would guess that if he did anything, he stuffed the damper with Fiberglass insulation.
  7. lumbering on

    lumbering on Feeling the Heat

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    The invoice doesn't specify anything other than the liner and installation so no help there.
    I'm going to assume their is a top cap plate, but no idea if there is insulation at the top (can't see up that far).

    BUT...there is definitely nothing at the base, it looks like a massive space (big 100+ year old fireplace).

    I am burning kiln dried wood and ecoblocks and even running it 24/7 now, I still can't get the room past 70 degrees. I'm guessing I'm heating the chimney and beyond.

    If I do stuff the base with roxul, and there is no insulation at the top cap plate, will I risk the flue gasses cooling too much as they go up a three floor external chimney and getting too much creosote?

    What gauge and what type of sheet metal are you using for DIY blockoff plates.

    Thanks again...
  8. lumbering on

    lumbering on Feeling the Heat

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    Also, Kaptjaq, I see you are on long island as well. Can you direct me to someone who you trust who might be able to help?
  9. webby3650

    webby3650 Master of Fire

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    Is the liner itself insulated? If so, then you don't need to worry about creosote build up in the flue. Just stuff the damper with insulation and/or block off with some 28 gauge sheet metal. You can get it in sheets from a HVAC supply store.
    At minimum the liner should be insulated and it should have insulation stuffed around the liner at the top to prevent heat from escaping.
  10. firebroad

    firebroad Minister of Fire

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    My installer wouldn't remember what he did either--but he does keep records;)
  11. webby3650

    webby3650 Master of Fire

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    He also probably has a standard, and wouldn't need to charge you to take a look.
  12. mellow

    mellow Resident Stove Connoisseur

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    Maybe he is wanting to use a pourable insulator down the chimney?

    [​IMG]
  13. Heatsource

    Heatsource Minister of Fire

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    i wasn't disagreeing with you, just making a comment about the term "insulate"
    :)

    and i totally agree that the installer should have records
  14. lumbering on

    lumbering on Feeling the Heat

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    I agree, if you can't remember, and don't have records, at least don't charge me for a service call to clear it up.

    No, the liner is NOT insulated.

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