Edit - changed a few items - don't remember what.
One thing to remember - check the liner manufacturers instructions before you insulate it - the liner is approved for insulation based on how it was insulated when tested - poured vermiculite may be suitable for one liner, but not another.
As well, remember that if you don't have the code required air spaces around the exterior of a masonary flue, insulating the liner can reduce these required clearances. We are all very up to speed on clearances around the stove itself, what about the liner, which can reach 1200F for very long periods of time. Pyrolisis (charcoal formation) does require the wood be "on fire" to occur, it can occur over many years of exposure to high heat without flame every occuring.
Edthedawg - in your pic further up the thread - floor boards contact the brick - you likely would need to insulate the liner to meet code requirements, as this is not likely to be the only place that structural timbers are in direct contact with the masonary flue. Insulating the liner IAW instructions (not just pouring vermiculite down around it) can provide you with reduced zero/zero clearance - zero air space required around the liner inside the brick chimney, zero airspace required outside the brick chimney to combustibles. Not many inspectors/installers seem keen on pointing this out to customers. I ended up getting "burned" and am now waiting for the installer to return to bring the install up to code.
Efficency is one thing, but insurability is another - in the end, not insulating the liner IAW instructions from the liner manufacture can result in you not being covered, because you may not meet code, especially in an older home.
Give the "Best Practices" link in my signature a read. And, no, I don't sell liners, or insulation, or even own an insulated liner - yet.
One thing to remember - check the liner manufacturers instructions before you insulate it - the liner is approved for insulation based on how it was insulated when tested - poured vermiculite may be suitable for one liner, but not another.
As well, remember that if you don't have the code required air spaces around the exterior of a masonary flue, insulating the liner can reduce these required clearances. We are all very up to speed on clearances around the stove itself, what about the liner, which can reach 1200F for very long periods of time. Pyrolisis (charcoal formation) does require the wood be "on fire" to occur, it can occur over many years of exposure to high heat without flame every occuring.
Edthedawg - in your pic further up the thread - floor boards contact the brick - you likely would need to insulate the liner to meet code requirements, as this is not likely to be the only place that structural timbers are in direct contact with the masonary flue. Insulating the liner IAW instructions (not just pouring vermiculite down around it) can provide you with reduced zero/zero clearance - zero air space required around the liner inside the brick chimney, zero airspace required outside the brick chimney to combustibles. Not many inspectors/installers seem keen on pointing this out to customers. I ended up getting "burned" and am now waiting for the installer to return to bring the install up to code.
Efficency is one thing, but insurability is another - in the end, not insulating the liner IAW instructions from the liner manufacture can result in you not being covered, because you may not meet code, especially in an older home.
Give the "Best Practices" link in my signature a read. And, no, I don't sell liners, or insulation, or even own an insulated liner - yet.
