New liner for my insert

[firemn260]

Hello I have been lurking here a while and found lots of great info so I signed up to ask for some advise.

I am installing a woodstove insert in a fireplace in my basement. I have a old kodiak insert that is in very good shape. The flu collar is 8" on this unit. The basment fireplace has never been used so the chimney is in great shape. It's lined with 13x18 terracotta.
My question is I'm going to do one of the flexible liners but I'm unsure if it will need to be insulated or not. I'm on a very limited budget but I still want to do it right. I found one company who states there double walled liner does not need to be insulated if the chimney is sealed top and bottom. Others I'm reading there liner needs to be insulated to be up to code. If that's the case I will need to do the cheaper single walled liner and insulation kit.
I guess being a fireman I already know the answer. That is not to cheap out on safety. I would just like to hear some opinions. Thanks

Matt

 

[weatherguy]

Is the chimney on an inner or outer wall? Mines an interior fireplace and I just insulated the top and bottom and put in a block off plate. Check out the flex liners at chimney liner depot, there's also some flex liner with built in insulation so if it fits down your flue its a easier way to do it.

 

[bholler]

Unless you have proper clearances to combustibles from the outside of the masonry structure it needs to be insulated to meet code. And if you do not insulate it for a wood burning appliance it voids the ul listing

 

[BruceNorEast]

I thought the terra cotta lining within the masonry chimney, top capped, and installing a ss liner, would meet code - without insulation!?!? If you need a town inspection then you could ask them, or someone at the fire station?

PS: Any chance you can install one floor up? Unless you have a finished basement and spend a lot of time down there, you may not get as much heat as you'd like. Since it isn't installed yet, you can still consider options... Good luck!

 

[bholler]

No it needs to be an insulated liner in order to get zeroclearance to combustibles on the exterior of the masonry. If you have the required 1" for an exterior chimney or 2" for an interior one it can be un insulated but i would still recommend it for performance reasons And that doesnt change the fact that when these liners are tested to ul-1777 standards they are insulated and in order to have that listing intact they need to be insulated

 

[bholler]

And by the way most code inspectors i have come across don't know either. Its kind of sad but they usually ask us if our install meets code when we run into them. At least here they are spread to thin with to little training

 

[BruceNorEast]

No it needs to be an insulated liner in order to get zeroclearance to combustibles on the exterior of the masonry. If you have the required 1" for an exterior chimney or 2" for an interior one it can be un insulated but i would still recommend it for performance reasons And that doesnt change the fact that when these liners are tested to ul-1777 standards they are insulated and in order to have that listing intact they need to be insulated

You may be right, but take a look at this - the article clearly says that if the required clearance is not met, it can be solved by adding a metal liner:
(broken link removed to http://www.woodstove.com/pages/guidepdfs/Masonry%20Chimneys.pdf)

I'll see if I can find any related code to quote, if you have it please post!

 

[bholler]

Ok even if you go buy the rule that if the liners are good (which is not what ul-177 says) all it takes is one joint between the liners to have a small area of missing mortar to make it not intact. And missing mortar somewhere is almost a given

 

[firemn260]

The chimney is on the exterior of the house. I am just going to go with the flex king pro and insulation kit to do it right. I will just have to bite the bullet and drop the 1200 or so for it.

I know most modern stoves run a 6" flu now days but I was wondering I will benefit any more or less by having a 8" flu?
My insert also came with the factory blower. Does anybody know how it's set up? Does it blow from the bottom around the back and out the top?
Thank you all for all your input. I know the liner question is a dead horse. Being a noon wood burner I appreciate any advise.

 

[bholler]

if you are planning on putting a new stove in in the future i would consider putting in a 7" liner Old stoves with 8" vents run pretty well on them especially if they are insulated and new stoves with 6" run fine to. I am sure there will be others who disagree but in my experience it works well