New guy decides not to use insulated liner--then hears the voice of reason

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of the 20 or so stove shops/installers I spoke with on the matter, none felt it was important if you burned truly seasoned wood and didn't smolder your fires.

Wonder, were they talking about a brick chimney WITH clay tile, or just naked unlined brick, as the OP has?

According to hearth.com, "If the chimney is not lined with clay tile... the liner must be insulated..."
My understanding is that if a masonry chimney does not meet the NFPA 211 standard, and one without a tile would not, then insulation is required to meet code.

Certainly many installers would not worry about meeting code, but I doubt it would be 20 out of 20.

The two sweeps I contacted (before doing the job myself) refused to install liners WITHOUT insulating... and that on an interior clay-lined flue! Personally, if I had a clay flue tile that was sized about right I'd skip the ss liner (and obviously the insulation) altogether, but the chances of that actually happening for anybody are pretty slim.
 
If my family had to take a cross country road trip I would feel better knowing they were in a car with anti lock brakes and airbags vs. lap belts and a metal dash.

If you have the option, choose the pipe that gives you extra safety and control margins. My previous house had an uninsulated pipe in a masonry chimney and it worked fine. If I was going to install one now I would overkill / over engineer the project.
 
i dont see how an uninsulated liner gets hot enough to get a brick hot enough to get any wood around it to combust.

On this point alone, ask a firefighter. Back in the day, as I went through Basic Structural Firefighter I in CT, our exercise was to lie on the floor and watch an empty concrete room flash over. Fire was nothing but a stack of maybe 6 pallets. As the secondaries lit on the ceiling the bricks and cinderblocks started exploding (spalling) so much that daylight appeared through cracks as if somebody was shooting holes in the walls.

Physics- it's not just a good idea. It's the law.
 
I had a mason here the other day forming up the old wall thimble (if you can call it that, basically fixing the old terracotta pipe to the chimney), and he said I should just stick stove pipe through the hole (horizontally), and use the unlined chimney. Old-timer, and not a sweep, so I'm not figuring I'll follow his guidance. but, I do want to avoid overkill.

On some things I *don't* want to avoid overkill. This is one of them. :)
 
Wonder, were they talking about a brick chimney WITH clay tile, or just naked unlined brick, as the OP has?

According to hearth.com, "If the chimney is not lined with clay tile... the liner must be insulated..."
My understanding is that if a masonry chimney does not meet the NFPA 211 standard, and one without a tile would not, then insulation is required to meet code.

Certainly many installers would not worry about meeting code, but I doubt it would be 20 out of 20.

The two sweeps I contacted (before doing the job myself) refused to install liners WITHOUT insulating... and that on an interior clay-lined flue! Personally, if I had a clay flue tile that was sized about right I'd skip the ss liner (and obviously the insulation) altogether, but the chances of that actually happening for anybody are pretty slim.

My chimney has a clay liner and this was certainly known to everyone I spoke with. There were a few that said they only used insulation in certain circumstances and while my memory isn't serving me well right this minute, you are likely on point about the clay being absent. Like I said though, I had to ask for the insulation wrap and even then was told it was unecessary from every shop installer and independent installer.
 
had to ask for the insulation wrap and even then was told it was unecessary from every shop installer and independent installer.

My impression is, sweeps suggest insulation always and shops suggest it rarely, regardless of the actual flue conditions or code compliance... just myobserbvation.
 
My chimney has a clay liner and this was certainly known to everyone I spoke with. There were a few that said they only used insulation in certain circumstances and while my memory isn't serving me well right this minute, you are likely on point about the clay being absent. Like I said though, I had to ask for the insulation wrap and even then was told it was unecessary from every shop installer and independent installer.
With a clay liner and block off plates I don't see why it would have to be insulated either..not saying I wouldn't though if the room was there.
You figure for years a lot of people burnt into clay tile flues with no problems.
 
With a clay liner and block off plates I don't see why it would have to be insulated either..not saying I wouldn't though if the room was there.
/quote]

Agree... but the OP has NO clay liner, and I think that is the point of the thread: clay = insulation optional, no clay = insulation highly recommended if not mandatory.
 
Definitely needs a insulated liner then...least I would.
 
Insulate that liner! I made the mistake of going on the cheap and doing that with my install, even though I had it spaced and the clearances did not touch the chimney, I did not like the buildup or heat loss inside the chimney.

Long story short it was a lot of work pulling that liner back out and insulating it.
 
On this point alone, ask a firefighter. Back in the day, as I went through Basic Structural Firefighter I in CT, our exercise was to lie on the floor and watch an empty concrete room flash over. Fire was nothing but a stack of maybe 6 pallets. As the secondaries lit on the ceiling the bricks and cinderblocks started exploding (spalling) so much that daylight appeared through cracks as if somebody was shooting holes in the walls.

Physics- it's not just a good idea. It's the law.

And let's not forget the potential issue of missing mortar (it happens over time and all it takes is one area with missing mortar) exposing heat and potential sparks/flames to nearby combustible materials (i.e. wooden framing -- which in an old chimney may or may not be at the required clearances.)

Not to mention the potential of good ol' pyrolysis . . . again . . . unlined chimneys many times are not built with the required clearances to combustibles.

Another vote for a bad idea to not use an insulated liner in an untiled chimney.

Some things are worth being cheap . . . not going with the super deluxe car model, opting for the value meal at McDonalds, deciding you can live with a 42-inch plasma TV vs. the 64 inch model . . . when it comes to something that can burn down my home, injure/kill my wife and pets and pretty much destroy everything I have worked for in life . . . well, suddenly spending a few hundred dollars more makes sense . . . heck, even a thousand dollars more to me would make sense. But that's just me.
 
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but these liner wraps are what? 1/4 to 1/2 inch of insulated wrapping, doesnt seem like enough to make a difference. Pouring loose insulation down a chimney where you have a couple inches all the way around the pipe i could understand. I guess whatever helps you sleep at night is the thing to do, never hurts to err on the side of caution.
 
That 1/2" of insulation and reflective blanket does a lot to contain the flue heat. 1" of insulation is what typically is in class A pipe and reduces clearances down from 18" (single wall) to 2" (class A). And that is clearance to wood, not tile inside of a chimney.
 
Not to mention the potential of good ol' pyrolysis . . .

This would be my concern... not that a one-time event would necessarily ignite the wood, but that repeated exposure to high-heat would make the wood more prone to eventually combust somewhere down the road. If you are timber framing abutting a brick chimney, whatever doesn't kill you makes you weaker, not stronger. If a chimney fire can reach 3000f, that brick's gotta be getting warm.
 
Had this happen in the home my wife grew up in. Took 40 yrs of random fires, but one very cold night when the fire was blazing, we smelled smoke... Fortunately the smoldering wood was extinguished, but that was too close for comfort.
 
Well, the advice in this thread got to me. Went with the Insulflex liner from Magnaflex. It was really a mix of all you in here and all the help that theheatelement (forum member here) gave me. I obviously haven't yet received my liner since I just ordered the pre-insulated 30' kit (6") , but I'm already impressed. We exchanged 22 emails, and in the end, I'm getting a good price on what I'm sure will be a great liner. I think their pre-wrapped is better priced than some of the other popular liner seller's kits that include the insulation wrap.

http://www.ebay.com/usr/chimneysolutions.hearth

Looks like a great choice!! I like it. :) The pre-wrapped version certainly looks like it will be easier to install also. Keep us posted on the outcome.

Kudos and Cheers!:cool:
 
Today was the day. I think the shipment of my liner got a little delayed due to weather, but for free shipping I can't complain. First, the good. The liner arrived, and it was great and as I had discussed with theheatelement. I needed a short body tee since I have no space below the crock I passed through. Here's a picture of my crock (ignore the terrible fire hazard that it is for a moment). So I basically attached the tee to the liner before putting it down the chimney, since there was no way to install it afterwards. Thankfully it had a short, removable snout. I did have to cut the tee down even though it was a short body tee. The disc grinder and hacksaw teamed up to get it done. See picture of tee after I cut it.
 

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So then, the install. First, it really shouldn't be done by one person. Thankfully I had a little help from my wife, but her pulling from below really didn't do much when we got snagged (a lot). I only have pictures of the easy part (the end) but here they are. note that the chimney looks really spacious, but it constricts a good bit about 4-5 feet down.

I really can't overstate how difficult this job was, standing on the roof and trying to manipulate both ends of a 30 foot liner, having to somehow twist it in just the right way to get it budge another foot. I'm glad it's done.
 

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Now we can talk about the crock. I knew there was some masonry around the terracotta, but I was pretty sure there wasn't enough, and I also knew the mantle had to go, too. So I began to explore, and found a negligible wall patch, with the lather running right up to the crock! And yeah, it looked a bit blackened. So, wanting to burn tonight, you can see what I did. I don't have all the right clearances (about eight inches to the right, and below the stove pipe), but it's a lot better than it was. No picture of the finale, but a couple of the process of breaking away the combustibles from the brick.

Right now I'm sitting next to a toasty stove, and even though the install is ugly right now, I'm feeling like it's quite safe and will serve me fine until I get the hearth dressed up.
 

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Big thanks to all of you for steering me right, and especially to theheatelement for his help off the forum. I'm definitely glad I went with the pre-insulated Magnaflex.

Still open for suggestions if you see something unsafe about what I've done. As far as I know the only clearances I'm not meeting are the 12" from the stovepipe, and I'm checking the wall frequently; it's barely warm.
 
Let's see some pics of that puppy burning. And keep us updated on how the Kent and the Magnaflex liner works for ya.
 
Here it is. Not the most aesthetically pleasing setup right now.
 

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Also, not the most legal setup. There is supposed to be 12" of brick or insulation in all directions from the thimble.
 
Big thanks to all of you for steering me right, and especially to theheatelement for his help off the forum. I'm definitely glad I went with the pre-insulated Magnaflex.

Still open for suggestions if you see something unsafe about what I've done. As far as I know the only clearances I'm not meeting are the 12" from the stovepipe, and I'm checking the wall frequently; it's barely warm.

Glad to hear you went with the insulated liner. And I have to agree with all your comments on the Insulflex and theheatelement - He was most helpful during my entire ordering experience, price was right, and I was kept fully informed of the progress. And the product seems to be far superior to a standard flex liner with an insulation kit added - I seem to have better draft in my 1st floor insert with a 14 foot Insulflex than I have in my basement insert with a 23ft insulated liner. Same insert, same install - only difference is the liner!
 
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