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Dense pack a lined chimney flue?

rhl_ | Posted in General Questions on

I’m installing a wood stove insert into my fireplace, with a chimney liner. The top of the chimney is capped off so “in theory” there is a cavity of dead air space in the chimney. In practice there will still be some air movement there, and also more importantly heat loss. I was thinking why not pack the chimney with mineral wool? Is that discussed on the site? Are there any designs/thoughts for how to hold the mineral wool in place for a sort of “standard” chimney?

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  1. Expert Member
    Dana Dorsett | | #1

    It's common practice to insulate the liner inside the flue with rock wool, but not dense-packed. Even loose-filled 15' or more of rock wool is pretty air retardent.

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