Chimney liner questions?

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john26

Minister of Fire
Hearth Supporter
Oct 27, 2008
798
Wildwood MO
I will be installing a Lopi Freedom in a masonry fireplace the chimney is on the side of the house approximately 25 to 30 feet tall. My first question is should I insulate the chimney (I am leaning that way) and second if I insulate should I wrap in the stainless mesh? any help is appreciated.
 
I will be installing a Lopi Freedom in a masonry fireplace the chimney is on the side of the house approximately 25 to 30 feet tall. My first question is should I insulate the chimney (I am leaning that way) and second if I insulate should I wrap in the stainless mesh? any help is appreciated.
Yes and yes
 
You can buy stainless steel chimney liner already insulated. Mine has a 6 inch flexible liner for the stove exhaust with half inch nonflammable insulation and then a larger flexible stainless steel covering the insulation. Overall diameter is 7.25 inches. It costs about $1000 for 30 feet. Make sure to have enough to reach the top of the chimney since they come in 5 foot increments.
Search for insulated chimney liner and you will be overwhelmed with results.
You will also need a top plate for the chimney to connect the liner at the top and maybe a connector at the bottom to connect the insert (not sure about Lopi inserts).
A block-off plate in the damper area is recommended to cut down heat loss.
 
I plan on using a top plate and fabricating a block off plate. I was going to order a chimney liner kit from menards and insulate it myself with 2300deg #8 foil backed 1/2" ceramic insulation. What is the purpose of the stainless mesh?
 
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I plan on using a top plate and fabricating a block off plate. I was going to order a chimney liner kit from menards and insulate it myself with 2300deg #8 foil backed 1/2" ceramic insulation. What is the purpose of the stainless mesh?
It is to keep the insulation protected and in place
 
liner through damper area my damper is 5.5" by 20" or so. Can I bend the liner to an oval shape then back round to hook to the insert? or do I need an oval adapter and oval liner? or should I cut part of the chimney hat out for clearance on the 6" round?
 
liner through damper area my damper is 5.5" by 20" or so. Can I bend the liner to an oval shape then back round to hook to the insert? or do I need an oval adapter and oval liner? or should I cut part of the chimney hat out for clearance on the 6" round?
Cut it out
 
I plan on using a top plate and fabricating a block off plate. I was going to order a chimney liner kit from menards and insulate it myself with 2300deg #8 foil backed 1/2" ceramic insulation. What is the purpose of the stainless mesh?

John26, have you ordered/used the insulation you're talking about yet? I found it at this link
(broken link removed)
Looks like you can save some money with this if it is the same quality as liner insulation kits intended for chimney liners. $120 for the foil backed 48 foot by 24". Seems like a pretty good price.
 
liner through damper area my damper is 5.5" by 20" or so. Can I bend the liner to an oval shape then back round to hook to the insert? or do I need an oval adapter and oval liner? or should I cut part of the chimney hat out for clearance on the 6" round?

I did exactly this. Ordered a 6" x 35' flexible stainless steel liner from Menards and insulated it myself. I ovalized the bottom portion of it to fit through the damper as we did not want to cut the damper in the (likely) event we sell the house once our son graduates.
 
If you take a round liner, and ovalize it, you now have reduced the air flow, even if you form it back to round after it goes through the damper opening. Cleaning will be easier and you'll get a better draft with a round liner.
Cut the damper opening and make room for the Round Liner. No one wants to go back to a Fireplace, and if they did, just put a Top Damper on the top of the Chimney, it will work a lot better than the metal on metal damper that you now have.
 
If you take a round liner, and ovalize it, you now have reduced the air flow, even if you form it back to round after it goes through the damper opening. Cleaning will be easier and you'll get a better draft with a round liner.

I'll grant you that ovalizing does change the overall cross sectional area of the liner but the opening of my damper was 5.75" so I did not need to ovalize too much and while I am not an engineer I think the 28 or so odd feet of insulated liner above it drafts extremely well. I sometimes worry that it drafts too well so perhaps the slight oval helps to slow that down? I don't know but we seem to do okay with our set-up.

Cut the damper opening and make room for the Round Liner. No one wants to go back to a Fireplace, and if they did, just put a Top Damper on the top of the Chimney, it will work a lot better than the metal on metal damper that you now have.

Yes, I would have much preferred to remove the damper in its entirety and dispense with the madness of navigating that obstacle. I agree that fireplaces are a well-intentioned but very poorly executed romance. Sure the idea of a fireplace sounds great but in the world of heating they are a horrendous waste. No one who understands heating with wood would ever go back to a fireplace but we live in an area where home-buyers will want the fireplace intact not necessarily because they are actually going to use it but because of some perceived loss in value. I realize what has worked for us may not necessarily work for everyone else.

To the OP I absolutely recommend insulating your liner when installing in a chimney located on an exterior wall. If you do it yourself make sure to compress the insulation as much as possible before wrapping with the mesh to cut down on the number of snags you encounter while installing the liner down the flue. For the OP if cutting or removing the damper is not an issue on resale then definitely pursue this route as it is much easier and gives you better access during the install.